Over 2 years since the Kivu Ebola epidemic began in August 2018, the US Food and Drug Administration (FDA) approved the first antibody cocktail for the treatment for Zaire ebolavirus (Ebola virus) infection in adult and pediatric patients.
The drug, called Inmazeb, was developed by Regeneron — a biotech company also testing an antibody treatment for COVID-19. In clinical trials, patients who took Inmazeb were far less likely to die from Ebola virus disease.
In the clinical trial conducted during the outbreak in the North Kivu region, those treated with Inzameb experienced 33.5% mortality after 28 days. The World Health Organization (WHO) reports the virus’ mortality rate can be as high as 90%, depending on the outbreak.
The PALM trial, Pamoja Tulinde Maisha (meaning “together save lives”), is a randomized, controlled trial of four investigational agents (ZMapp, remdesivir, mAb114, and REGN-EB3, now called Inmazeb) for the treatment of patients with Ebola virus disease.
To help control the Ebola virus outbreak, Inmazeb is being administered for free in the DRC with the support of the Biomedical Advanced Research and Development Authority (BARDA), and Regeneron has stated that it is working with non-governmental organizations and public health agencies to make sure the treatment is accessible to low- and middle-income countries.
This trial and other studies done during Ebola outbreaks over the past decade showed that it was possible and operationally feasible to conduct scientific research during an epidemic. Researchers are now applying those lessons during the COVID-19 pandemic. One of the US-based trials for the antiviral remdesivir, which the FDA authorized for emergency use, was modeled after the PALM trial.
“Today’s approval highlights the importance of international collaboration in the fight against Ebola virus,” said John Farley, MD, MPH, director of the Office of Infectious Diseases in the FDA’s Center for Drug Evaluation and Research, in a press release.
Zaire ebolavirus, commonly known as Ebola virus, is one of four Ebolavirus species that can cause a potentially fatal human disease. Ebola virus is transmitted through direct contact with blood, body fluids and tissues of infected people or wild animals, as well as with surfaces and materials, such as bedding and clothing, contaminated with these fluids. Individuals who provide care for people with Ebola virus, including health care workers who do not use correct infection control precautions, are at the highest risk for infection. Ervebo, the first vaccine for the prevention of Ebola was approved by the European Medicines Agency in October 2019 and the US FDA in December 2019.
For the Democratic Republic of the Congo, the coronavirus is the least of their worries. Despite the country had almost surpassed an Ebola outbreak in its eastern provinces, health officials have announced the emergence of a new cluster on the opposite side of the country.
The outbreak started in the western port city of Mbandaka, but it’s not clear yet how. The World Health Organization first reported four deaths to the virus followed by UNICEF stating that five people, including a 15-year-old girl, had died between May 18 and Sunday when health officials confirmed they were Ebola-related fatalities.
The new outbreak comes at the same time the Congo is dealing with the coronavirus epidemic, with already 3,200 positive cases and 72 deaths, as well as a large measles outbreak, with 369,500 infections and nearly 6,800 deaths since 2019 when the outbreak began.
“This is a reminder that COVID-19 is not the only health threat people face,” said Dr Tedros Adhanom Ghebreyesus, WHO Director-General, in a statement. “Although much of our attention is on the pandemic, WHO is continuing to monitor and respond to many other health emergencies.”
This is the 11th outbreak of Ebola that Congo has seen since it first emerged in 1967 and it’s happening simultaneously with the 10th outbreak in the northeastern provinces of North Kivu, South Kivu and Ituri – declared in 2018 but now in its final phase.
The WHO was about to declare the 10th outbreak over when a new case was confirmed on April 10. Then, on May 14, the country started a 42-day countdown to the declaration of the outbreak’s end. Nevertheless, the WHO said new outbreaks are likely to happen as the virus is living in animal reservoirs across the country.
“It’s happening at a challenging time, but WHO has worked over the last two years with health authorities, Africa CDC and other partners to strengthen national capacity to respond to outbreaks,” said in a statement Dr Matshidiso Moeti, WHO Regional Director for Africa.
A team from the WHO is already in Mbandaka supporting the response to this new outbreak, as part of the capacity built during the 2018 outbreak. The team supported the collection and testing of samples, sending them to the national laboratory for confirmation.
Understanding the Ebola virus
The Ebola virus is a severe, often fatal, illness that affects humans and other primates. It’s transmitted to people from wild animals such as fruit bats and then spreads in the human population via direct contact with the blood and other bodily fluids of the infected people and with surfaces contaminates with the fluids.
The first Ebola outbreak happened in remote villages in Central Africa, near tropical rainforests. The 2014–2016 outbreak in West Africa was the largest and most complex Ebola outbreak since the virus was first discovered in 1976. There were more cases and deaths in this outbreak than all others combined.
Vaccines to protect against Ebola are currently under development and have been used to help control the spread of Ebola outbreaks in African countries. There is no licensed treatment proven to neutralize the virus but a range of blood, immunological and drug therapies are under development.
The European Commission (the EU’s executive branch) has approved a functional Ebola vaccine, Ervbo, for human use. This is the first treatment of its kind to ever show efficacy in humans.
In an announcement on November 11, the European Commission granted Merck Sharp and Dohme B.V. marketing authorization for Ervebo in Europe. The European Medicines Agency, EMA, first recommended approval of the vaccine in October this year. A functional Ebola vaccine meant for human use has been a goal of the global research community ever since the massive outbreak in West Africa between 2014 and 2016.
A world first
This is the first time a vaccine for the disease that works in humans has been introduced for the dreadful disease. The Ebola virus can cause severe hemorrhagic fever, which involves both a rise in body temperature and massive internal bleeding from blood vessels throughout the body. The virus firsts attacks immune cells, which impairs our body’s early defenses. Eventually, macrophages do start striking back, but as they digest the virus, the cells release proteins that lead to the formation of small blood clots and inflammation, and cause leaks in your blood vessels. This is a very severe process that leads to a patient’s internal organs being starved for oxygen — around 90% of those infected by the virus die in this stage, according to the World Health Organization (WHO) Africa Region Office.
Until now, the only real way to protect yourself against Ebola was to avoid being contaminated — which is obviously hard in a full-blown outbreak. The only thing close to a functional vaccine for humans was a vaccine that worked in macaques, developed by researchers at the Public Health Agency of Canada’s National Microbiology Laboratory.
The new vaccine works by exposing patients to a form of the virus that can’t cause an infection. Our bodies can thus interact with the pathogen and learn how to fight it when the real virus comes around. It has been tested in an attempt to control Ebola outbreaks in the Democratic Republic of the Congo (DRC), showing great promise: the vaccine had an estimated protective efficacy of 97.5% in field studies. That’s a remarkable result in the best of conditions, and especially in the volatile conditions in the DRC, which is still struggling to recover from a series of civil wars.
Now that the European Commission has stamped its approval on the vaccine, there is a lot of interest that other regulatory bodies follow suit. The Food and Drug Administration (FDA) in the US is currently reviewing the vaccine for approval and could give the green light sometime in early 2020. However, Merck doesn’t expect the vaccine to make a lot of money: vaccines are, traditionally, not very lucrative, and Ebola is most prominent in poorer countries. The global health community might need to step in and support (i.e. fund) the use of the vaccine for it to reach as many of the people that need it as possible.
The human medicines committee (CHMP) of the European Medicines Agency (EMA) has recommended granting a conditional marketing authorisation in the European Union for Ervebo (rVSVΔG-ZEBOV-GP), the first vaccine to protect individuals (18 years and older) from Ebola virus infection.
The Ebola virus causes hemorrhagic fever and spreads from person to person through direct contact with body fluids. Death rates in patients who have been infected with the virus have varied from 25% to 90% in past outbreaks. The largest outbreak to date occurred in West Africa in 2014 to 2016 with over 11,000 deaths. The current outbreak in the Democratic Republic of Congo (DRC), caused by Ebola Zaire, has shown case fatality rates around 67%.
“This is an important step towards relieving the burden of this deadly disease,” said Guido Rasi, EMA’s Executive Director. “The CHMP’s recommendation is the result of many years of collaborative global efforts to find and develop new medicines and vaccines against Ebola. Public health authorities in countries affected by Ebola need safe and efficacious medicines to be able to respond effectively to outbreaks and save lives.”
The clinical development of Ervebo was initiated in response to the 2014-2016 Ebola outbreak in cooperation with public health stakeholders, including national institutes of health, ministries of health in countries such as Guinea and DRC, WHO, the US Centers for Disease Control and Prevention, the Public Health Agency of Canada, Médecins Sans Frontières and others.
Ervebo has been tested in approximately 16,000 individuals involved in several clinical studies in Africa, Europe and the United States where it has been proven to be safe, immunogenic (i.e. able to make the immune system respond to the virus) and effective against the Zaire Ebola virus that circulated in West Africa in 2014-2016. Preliminary data suggest that it is effective in the current outbreak in DRC. Additional efficacy and safety data are being collected through the Expanded Access Protocol and should be included in post-marketing safety reports, which are continuously reviewed by EMA.
Ervebo was supported through EMA’s PRIority MEdicines (PRIME) scheme, which provides early and enhanced scientific and regulatory support to medicines that have a particular potential to address patients’ unmet medical needs. Ervebo was granted eligibility to PRIME in June 2016 for active immunisation against Ebola.
The US Food and Drug Administration (FDA) fast-tracked the vaccine’s application for approval in September and decision is expected in March 2020. Seven other experimental Ebola vaccines are at earlier stages of development.
The Ebola outbreak in the eastern Democratic Republic of the Congo (DRC) is finally waning. Since the outbreak began in August 2018, almost 3,250 people have been infected and more than 2,150 have died. But the decrease in infections is not a reason to relax efforts to contain the virus, according to WHO director-general Tedros Adhanom Ghebreyesus. Health authorities in Kinshasa said last week they planned to introduce an experimental second Ebola vaccine, developed by drugmaker Johnson & Johnson, in the country’s eastern provinces in November.
Meanwhile, Japan imported the Ebola virus and four other deadly pathogens (Marburg and Lassa viruses and viruses that cause South American hemorrhagic fever and Crimean-Congo hemorrhagic fever) to prepare diagnostic tests for the 2020 Olympics, according to a report in Nature.
The first-ever multi-drug randomised trial for Ebola has proven extremely successful. Researchers treating patients in the Democratic Republic of Congo (DRC) have identified two monoclonal antibodies that block the Ebola virus and radically lower mortality. The new findings suggest that Ebola is no longer an incurable disease.
“Now we can say that 90 percent can come out of treatment cured,” one scientist said in a statement.
Ebola is a devastating disease, characterized by a painful hemorrhagic fever, which interferes with the endothelial cells lining the interior surface of blood vessels and with coagulation. As the blood vessel walls become damaged and destroyed, the platelets are unable to coagulate, and patients succumb to hypovolemic shock.
When the Ebola virus infects a human host, it it can kill up to 90% of the time, depending on available treatment. The 2014–2016 outbreak in West Africa was the largest and most complex Ebola outbreak since the virus was first discovered in 1976. There were more cases and deaths in this outbreak than all others combined.
To contain the epidemic, doctors in Sierra Leone, Libera, and Guinea have been using biopharmaceutical drugs like ZMapp and Remdesivir. However, these drugs have now been droppped in favor of two monoclonal antibodies, known as REGN-EB3 and mAb-114, which a recent clinical trial showed to be far more effective.
The DRC trial, which started in November, found that a monoclonal antibody drug made by Regeneron has a mortality rate of only 29% while another monoclonal antibody made by Ridgeback Biotherapetics had a mortality rate of 34%. Meanwhile, Zmapp and Remdesivir had a mortality rate of 49% and 53% respectively.
The odds of suriviving Ebola, however, are much higher if a patient arrives early at a clinic. The trial found that the death rate for those seeking treatment soon after they became sick was only 11% with the Ridgeback antibody and just 6% with Regeneron’s drug.
According to the World Health Organization, people who fall ill with Ebola wait on average four days before they seek treatment. Many are reluctant to call for help because the chances of survival in clinics has been very low — until recently, up to 70% of those infected with Ebola in the DRC have died.
This may finally change with this groundbreaking trial now that Ebola is preventable and treatable.
Scientists have discovered a new Ebola virus called Bombali. No, there is no outbreak; this new species was identified before it could reach humans.
Bombali is not a portmanteau of Bombay and Bali; it is a novel virus in bats in Sierra Leone named after a district in the north of the country where it was found. This was two years after the end of an outbreak that infected over 29,000 people and killed over 11,300 across West Africa. The West African outbreak was caused by the Zaire species, which has so far been the most lethal in humans since it was first discovered in 1976.
The new Ebola species was discovered by the PREDICT Ebola Host project composed of scientists from the University of California Davis’s One Health Institute and Columbia University’s Center for Infection and Immunity, who were working with the government of Sierra Leone and the University of Makeni and Metabiota.
PREDICT predicting potential pathogenic threats.
PREDICT is a partnership between USAID, the EcoHealth Alliance, Metabiota, the Wildlife Conservation Society, and the Smithsonian Institution which enables global surveillance for pathogens that have the potential to spill over from animal hosts to people. The Bombali virus has the potential to infect human cells, but at the moment, it is unknown if the virus has already caused human infection or is harmful to humans.
“Identifying new viruses like Bombali in wildlife and testing their capacity for human infection can enhance our understanding of the pre-emergent viral diversity circulating in animals,” said Professor Simon Anthony, a virologist at Columbia University’s Mailman School of Public Health and co-author of the publication. “We want to discover viruses that have the genetic prerequisites for human infection and then prioritize them for further study and intervention.”
Bats Likely Hosts of Ebola Viruses
Bats can reportedly eat up to 1000 mosquitoes an hour. Photo via PD-USGov.
Before the discovery of Bombali, five Ebola virus species had been identified in previous publications. Bombali Ebola is different from the Zaire Ebola, which killed thousands of people between 2013 and 2016. Despite more than 40 years of research, the reservoir hosts for these viruses is still unknown.
The discovery of Bombali adds to growing evidence that bats are the likely hosts of these viruses. It was also recently discovered that bats seem to be the perfect hosts for many viruses.
Relax. Do Not Kill or Stress Out the Bats
Scientists emphasize that people should not try to exterminate or eradicate bats in response to this new discovery. When bats are under a lot of stress from humans, healthy bats grow weak and become more susceptible to getting infected with viruses and can then spread Ebola to other places as they flee their habitats. Furthermore, bats eat night-flying insects, including many agricultural pests. As one of the major predators of night-flying insects, bats play an important role in controlling insect populations, helping to control pests that are able to transmit diseases and destroy crops. More than a quarter of currently-known bat species feed on fruit or nectar, pollinating many plants and dispersing seeds in the process.
Reduce Exposure to Reduce Risk of Infection
So, what do we do to prevent potential outbreaks of bat viruses? Bats infected with Bombali virus are not known to show signs of illness but they can shed the virus in their feces and saliva. People are advised to avoid contact with the urine or feces of bats. Researchers are working with communities living near the areas where Bombali Ebola-infected bats live to know more about this new species, study the interactions between bats and humans, and educate the communities on how to live safely with bats by reducing their risk of exposure to the virus.
The devastating Ebola outbreak in the Democratic Republic of the Congo (DRC) is probably over, health officials report.
Scanning electron micrograph of Ebola virus budding from the surface of a Vero cell (African green monkey kidney epithelial cell line). Image and captions credits to NIAID / Flickr.
On May 8, 2018, the Democratic Republic of Congo’s health minister declared an outbreak of Ebola. The highly deadly disease had killed over 11,000 people in West Africa between 2014 and 2016, so everybody was, understandably, Not Very Excited. However, I’m sure everyone will be jubilating for this tidbit: the outbreak in Congo is almost assuredly over.
The outbreak in DRC was the most severe since the 2014-2016 event, but it’s probably over. As of Wednesday, all individuals who came into contact with the last-confirmed infectee have passed the 21-day incubation period of Ebola without showing any signs of infection themselves. Because of this, health officials don’t need to monitor anyone on a daily basis. However, they want to be extra-safe — so they will keep monitoring the situation for another three weeks before officially declaring the outbreak over.
A total of 38 cases were confirmed during the outbreak and 14 deaths. A further 15 deaths may be tied to the outbreak, but the link can’t be confirmed as of yet. All suspected cases over the past three weeks have turned out to be negative.
Before the outbreak can be officially declared over, two incubation periods (42 days) must pass without any new confirmed case.
The outbreak was first declared on May 8, as a cluster of cases was confirmed in the deep rainforests of DRC’s Equateur province. The virus made its way to Mbandaka — a city of 1.2 million and an important local transport hub along the Congo and Ruki rivers, both heavily navigated — three weeks after the first cases were confirmed.
Although Ebola is endemic to Congo’s jungles — so health officials here are world-leading experts in containing the virus — it was a nerve-wracking time for health officials, as Ebola is very hard to contain in densely populated areas. The possibility of it spreading down the two rivers further complicated containment efforts.
“This outbreak has been the most challenging and complex outbreak the country has ever had to face, mainly because it started in two rural zones at the same time and quickly reached a city of more than 1 million inhabitants directly connected to Kinshasa, our capital city where 12 million Congolese live,” DRC’s minister of health, Oly Ilunga, told The Washington Post.
“Yet thanks to a rapid national and international mobilization as well as a great government-led coordination of the response, we managed to contain this outbreak in just seven weeks.”
The minister further explained that authorities tracked and monitored over 1,706 people confirmed or suspected to have contacted infected individuals. The process (known as ‘contact tracing’) required authorities to establish a vast surveillance network to track people’s movements from town to town and report any cases of fever that could be Ebola.
In this particular outbreak, however, tracing teams also worked to identify candidates for an experimental Ebola vaccine that had only been used once before, in the waning days of the West African epidemic. Over 3,300 people were ultimately administered the vaccine. Ilunga considers the vaccine nothing short of a “game-changer.”
The news certainly calls for celebration — but they are far from a definite end to the disease.
“As Ebola is a virus whose natural reservoir is located in the Equatorial Forest, we must prepare ourselves for the 10th Ebola outbreak,” said Ilunga.
“Moreover, with the greater mobility of the population, we can expect to have other outbreaks in urban zones in the future. We must learn the lessons from this response and strengthen our system in order to detect and respond even more efficiently to the next outbreak.”
The World Health Organization (WHO) confirmed a second Ebola case on Sunday, in the Democratic Republic of Congo — with many other cases remaining uncertain.
A 3D medical animation still of Ebola Virus. Image credits: Scientific Animations.
Health officials are trying to find 125 people who have been linked to the 19 suspected or already confirmed cases. Three people from the 19 have already lost their lives, and the there is a growing concern that more unreported cases still exist. It’s unclear how the first victim contacted the disease, though the WHO says past outbreaks have usually been linked with infected bush meat such as apes.
Last year, the Ebola outbreak killed more than 11,300 people, most of them in Guinea, Sierra Leone and Liberia. Congo, however, has had a different experience with the disease. Despite the fact that it was first detected there in 1976, Congo has had several smaller outbreaks but was relatively successful at containing them, avoiding massive loss of life. This is the 8th outbreak to ever hit the country, more than any other country in the world.
“Our country must confront an outbreak of the Ebola virus that constitutes a public health crisis of international significance,” the ministry said in a statement. “Our country is full of people well-trained in this matter and our health professionals also helped contain similar epidemics in other countries,” it added.
Still, this doesn’t mean that Congo is safe from large-scale outbreaks or that there’s no need to worry about the disease spreading to other countries. Treatment options are limited in Congo and neighboring areas. However, the WHO has an agreement with a drug developer which created an Ebola vaccine. They are now working to establish if deploying the vaccine is warranted.
“There are 300,000 doses of Ebola vaccine available if needed to stop this outbreak becoming a pandemic,” said GAVI’s chief executive Seth Berkley. “The vaccine has shown high efficacy in clinical trials and could play a vital role in protecting the most vulnerable.”
Ebola virus disease (EVD), formerly known as Ebola haemorrhagic fever, is a severe disease, often fatal in humans (with a survival rate of about 50%). The virus can be transmitted from wild animals to humans (which is how outbreaks generally start), but also from human to human. Limiting the expanse of the disease in wild animals would also help prevent future human outbreaks. Professional help is almost always required for disease containment, but even simple measures such as rehydration, basic hygiene, and symptomatic treatment can significantly improve survival rate. At the moment, there is no licensed treatment to eliminate the virus, though several studies are reporting progress.
Like humans, chimpanzees and gorillas can get infected with Ebola. Just like humans, they too can suffer from epidemics. To protect them from the disease as well as prevent it from spilling onto human populations, researchers have been working on an oral vaccine to combat Ebola in the wild. Results have been very encouraging, but researchers run into legal, political, and ethical obstacles that make it difficult to push the research further.
Image: USAID Africa Bureau.
Ebola has devastated wild apes populations. In the past three decades alone, the disease wiped out a third of wild populations. Chimps have also suffered from the disease, and Ebola has repeatedly shown that it can jump from them to us and back to them. Furthermore, the virus can jump to fruit bats (perhaps the most prolific spreader of the disease), monkeys, forest antelopes, and porcupines. Needless to say, the fewer infected animals we have in the wild, the better.
Considering all of this, researchers have been working on an edible vaccine for several years already — something which has been described as a glimmer of hope.
“In 2014 the world was gripped by fears of an Ebola virus pandemic. Yet few people realise that Ebola has already inflicted pandemic scale mortality on our closest relatives,” says lead researcher Dr Peter Walsh from the University of Cambridge. African apes are also threatened by naturally occurring pathogens like anthrax, and the increasing overspill of human pathogens such as measles. A glimmer of hope lies in the fact that many of the disease threats are now vaccine preventable.”
The new vaccine has proven not only effective but also shows minimum side effects. All that is needed to make sure that the vaccine will have a positive effect in the wild is to test it more… and this is where the problems start.
A terrible irony
After decades of using chimpanzees to test drugs for humans, the US — the last developed country still using chimps for such tests — closed the research facilities and banned subsequent testing. At the time, this was viewed as a great victory for animal rights but ironically, it may end up costing populations in the wild.
The carcass of a chimpanzee killed by Ebola in the Republic of Congo. (Image: Peter D. Walsh et al., 2017).
Any vaccination for wild animals must be tested in captivity first to ensure its safety. There have been some tests, but not really enough to get the ball rolling — it may be that the law that protects chimps may end up hurting wild populations.
“We have developed a very promising tool for inoculating ape species against the myriad deadly diseases they face in the wild, but continued progress relies on access to a small number of captive animals. This may be the final vaccine trial on captive chimpanzees: a serious setback for efforts to protect our closest relatives from the pathogens that push them ever closer to extinction in the wild.”
So now we have a vaccine which seems to work but needs more testing. The vaccine is set to help wild chimp and ape populations. But testing is no longer legal because we tested human drugs on chimps. It really is ironic, and while it is legal to experiment on chimps when it benefits their species, such funding is extremely limited. Sadly, no one seems to be willing to provide the necessary funds, even though this is about more than just protecting our closest relatives (which by the way, should be enough) — it’s about protecting ourselves as well. If we limit the expanse of Ebola through the wildlife, we reduce the chance of another pandemic.
Researchers argue that many zoos and sanctuaries have much worse conditions than research facilities — especially considering that the vaccine is safe and has almost no side effects.
“Some pressure groups argue that all research on captive chimpanzees is tantamount to torture, not just because of procedures but also due to confinement,” says Walsh.
“Enclosures and animal care are now of a very high standard, with chimpanzees housed in large social spaces. The modest traces of stress we detected during our trial were akin to the values observed in college students anticipating exams.”
At the end, we are faced with a difficult ethical dilemma:
“In an ideal world, there would be no need for captive chimpanzees,” says Walsh. “But this is not an ideal world. It is a world where diseases such as Ebola, along with rampant commercial poaching and habitat loss, are major contributors to rapidly declining wild ape populations.
“Oral vaccines offer a real opportunity to slow this decline. The major ethical debt we owe is not to a few captive animals, but to the survival of an entire species we are destroying in the wild: our closest relatives.”
The Ebola epidemic which killed more than 11,300 people between 2013 and 2016 had a secret weapon, researchers found.
This figure depicts the finding that an Ebola glycoprotein mutant that arose early during the West African epidemic increases infectivity of human cells and may have contributed to increased mortality. Image credits: Luban et al./Cell 2016
Scientists identified a mutation that changes the part of the virus which fits into the receptors of hosts cell. The mutant viruses were “better at fitting into the lock and got into the cell better,” said Jeremy Luban, a virologist at the University of Massachusetts Medical School, who led one of the studies describing the mutation. This mutation allowed it to cause such a long-lasting and devastating outbreak.
“Ebola virus is thought to circulate in an unknown animal reservoir and to only rarely cross over into people. When the virus does cross over, the effect has been devastating to those people who are infected. Until recently, the human disease outbreaks have been short lived, and the virus has had little opportunity to adapt genetically to the human host,” says Luban.
Basically, within months, the mutant strain of the virus was dominating the outbreak. But interestingly, the mutation doesn’t improve its chances in other creatures. So in essence, the virus developed a mutation tailored specifically for humans, targeting our species and nothing else. That’s a bit worrying, to say the least.
“If you introduce a virus into a new host, like humans, it may need to adapt to better infect and spread in that host,” says Jonathan Ball, a virologist at the University of Nottingham and co-author of the other paper.
If anything, this indicates that we have to keep a closer eye on such outbreaks. The Ebola pandemic was way more serious than most people anticipated, and in the future things could get even worse. After all, we don’t really understand viral evolution that well.
“I think really what it does say is you need to be carefully monitoring what’s happening to viruses as they spill over,” Ball said. “We know that these viruses are causing human infection, we know that they’re evolving, but do we really know what that evolution means?”
Reminiscent of the 2014-2015 Ebola panic, news of the Zika epidemic has spread like wildfire. The virus, which was once a serious risk for expectant mothers in Brazil, may be well an “explosive pandemic” deserving of international attention from the World Health Organization (WHO).
What is Zika?
Adult Aedes aegypti mosquito, a vector or carrier of the Zika virus. Credit: Wikimedia Commons
A virus transmitted primarily by mosquitoes, Zika may cause the infected person to develop symptoms such as fever, headache, joint pain, rash or conjunctivitis. However, only roughly 20% of those with the Zika virus are symptomatic.
“In many ways the Zika outbreak is worse than the Ebola epidemic of 2014-15…[because] most virus carriers are symptomless. It is a silent infection in a group of highly vulnerable individuals — pregnant women — that is associated with a horrible outcome for their babies,” said Wellcome Trust head Jeremy Farrar about the virus.
Credit: Wikimedia Commons
The primary concern of the Zika virus is that correlates to birth defects in babies born to affected mothers. While the link has not yet been proven, infected unborn babies are at high risk to develop microcephaly. Microcephaly is a sometimes fatal disease, in which the affected baby’s brain is smaller than average, with underdeveloped functioning.
Mosquitoes primarily transmit the Zika virus, and it’s mostly commonly been found in Brazil and equatorial climates.
A few cases have also documented sexual transmission of the virus. Experts recommend waiting to try to get pregnant for several weeks after returning from South or Central America. The delay is an extra precaution against having a baby with microcephaly.
The spread of the virus is limited by climate, by mode of transmission, by expiration of the virus in the blood of an affected person and by preventative measures the rest of the world can take in the meantime.
How does Zika compare to Ebola?
Unlike Ebola, Zika has not been reported as deadly to infected persons. Neither does it remain in a person indefinitely. So far, those infected with Zika appear to retain the virus in their blood for a week, and in semen for up to two weeks.
Reports of Zika outbreaks have increased at a staggering rate of 2500% from 2014 to 2016, however, leading the WHO to declare it a global public health emergency. The 4,700 reported cases of Zika in 2015-2016 still pale in comparison to the 11,000 deaths from Ebola in 2014-2015. The rate of increase may not bode well regarding the spread of Zika in the coming years, but fortunately the virus is not transmitted as easily person-to-person as Ebola.
How can you take precaution?
Pregnant women or those who may become pregnant are advised to steer clear of tropical countries. Couples are advised to wait one month before having unprotected sex after the man has been potentially exposed to the virus. Additional precautions include wearing bug repellant, emptying pools of standing water and covering up to prevent bites.
After a week of having the virus, infected persons should be fully recovered. However, many unknowns surround the disease — which is why exercising caution for a month following any travel to countries with reported Zika outbreaks is strongly recommended.
While the virus is spreading at an alarming rate, IFL Science writer Justine Alford also points out that infections will not always lead to an epidemic within a country or across the globe. Countries without carrier mosquitoes do not need to panic. However, prevention measures and additional studies are needed so that countries and organizations will be ready to react if the need arises.
It’s the first time since March 2014 that the three African countries at the heart of the Ebola epidemic have not reported a new case of the outbreak.
The Ebola Virus Epidemic in 2014 and 2015 killed somewhere between 50% and 70% of all the people it infected, being one of the most dangerous outbreaks in modern history. It was the first Ebola outbreak to reach epidemic proportions, especially aided by a dysfunctional healthcare system, a mistrust of government officials after years of armed conflict, and the delay in responding to the outbreak for several months. At the heart of this outbreak, there were three countries in West Africa: Liberia, Sierra Leone and Guinea. The first two countries alone had over 80% of all reported cases, and for a time, it seemed like the situation couldn’t be controlled and would continue to spread.
But thanks to interventions by doctors, local authorities and the WHO, cases in 2015 fell sharply. Liberia has already been declared free of the disease after 42 days without a new case, while Sierra Leone had its last one on 28 September and Guinea’s last case was on 27 September – this means that we have over one week without a new case, which is, of course, quite a positive development.
However, the WHO warns that the disease could pop up again at any time, especially as the whereabouts of several “high-risk” people linked to recent patients in Guinea and Sierra Leone are not known.
A vaccine against Ebola has proven itself 100% effective in a new trial carried out during outbreaks of the disease in Guinea, and promises to bring the epidemic to an end, scientists claim.
The vaccine, after being approved for testing by WHO. Image via ibtimes.co.uk
The trials involved 4,000 participants, and the results are spectacular – the vaccine was developed and tested in an astonishingly short time. Scientists, doctors, donors and drug companies collaborated to race the vaccine through a process that usually takes more than a decade in just 12 months.
“Having seen the devastating effects of Ebola on communities and even whole countries with my own eyes, I am very encouraged by today’s news,” said Børge Brende, the foreign minister of Norway, which helped fund the trial.
“This new vaccine, if the results hold up, may be the silver bullet against Ebola, helping to bring the current outbreak to zero and to control future outbreaks of this kind. I would like to thank all partners who have contributed to achieve this sensational result, due to an extraordinary and rapid collaborative effort,” he said on Friday.
Although the outcome of many cases is yet unknown and the final tole will be a lot heavier, a total of 27,748 recorded cases in Guinea, Liberia and Sierra Leone up to 26 July and 11,279 reported deaths make the outbreak in Africa the most devastating flare-up of the Ebola virus we have ever witnessed. In the week ending 26 July, there were just four new cases in Guinea and three in Sierra Leone.
A lot of work has been put into developing fast, reliable methods of identifying patients infected with the virus, but up to now, there was no reliable vaccine. So how did they do it?
Put a ring on it!
Because the number of cases in West Africa is diminishing, and due to the shifting nature of the epidemic, with small but sudden outbreaks all over the region, researchers used a novel method of testing out the vaccine.
The “gold standard” for vaccine testing is to administer it to 50% of the population, while giving the remaining half a placebo. Instead of this, a “ring” method was preferred, similar to that which helped prove the smallpox vaccine worked in the 1970s.
When Ebola erupted in a village, researchers administered the vaccine to the (willing) relatives, neighbours, friends and people who came in contact with the sick, and those that came in contact with this first “ring” of people, in an attempt to contain the virus. Children, adolescents and pregnant women were exempt from the vaccination as there was no safety data for them. In practice, an average of 50% of people in these clusters were administered the treatment.
The Ebola virus. Image via telegraph.co.uk
To test how well the vaccine protected people, the clusters were randomly assigned either to receive the vaccine immediately or three weeks after Ebola was confirmed. Among the 2,014 people vaccinated immediately, there were no cases of Ebola from 10 days after vaccination – allowing time for immunity to develop – according to the results published online in the Lancet medical journal (pdf). In the clusters with delayed vaccination, there were 16 cases out of 2,380.
WHO made it happen
The trial was sponsored by the World Health Organisation, as “nobody wanted to step into this role so we took the risk”, said assistant director-general, Dr Marie-Paule Kieny.
Funding came from the Wellcome Trust and other partners, including the governments of Norway and Canada.The British government contributed £1m of the trial funding and has said it will increase that amount to help allow the testing to continue.
Others involved included Médecins sans Frontières, whose volunteer doctors were on the front line, and the London School of Hygiene and Tropical Medicine. About 90% of the trial staff were from Guinea, a country where no clinical research had been carried out before. The vaccine is made by Merck.
“We believe that the world is on the verge of an efficacious Ebola vaccine” said Kieny.
In terms of vaccine trials, the number of people it was trialed on is small but very promising, said Kieny. She expects that the success rate once more people are treated with the vaccine will stabilize somewhere around 75-100%.
The authors of the research believe the ring design made it “logistically feasible” to conduct trials even in poor countries in the middle of a fading epidemic and it was a promising strategy for the future.
“This trial dared to use a highly innovative and pragmatic design, which allowed the team in Guinea to assess this vaccine in the middle of an epidemic,” said Jeremy Farrar, director of the Wellcome Trust and one of the world’s leading experts on infectious disease. “It is a remarkable result which shows the power of equitable international partnerships and flexibility.
“Our hope is that this vaccine will now help bring this epidemic to an end and be available for the inevitable future Ebola epidemics. This partnership also shows that such critical work is possible in the midst of a terrible epidemic. It should change how the world responds to such emerging infectious disease threats.”
John-Arne Røttingen, the head of infectious disease control at the Norwegian Institute of Public Health and chair of the trial’s steering group, said it had been a race against time in the most challenging circumstances.
“We are really pleased with the interim results,” he said. “It is really important to add the vaccine to the traditional hygiene measures we have used in the response so far. I believe this will be an important contribution to getting down to zero cases.”
Médecins sans Frontières said it was keen for the vaccine to be used in Sierra Leone and Liberia, where there were still cases.
“With such high efficacy, all affected countries should immediately start and multiply ring vaccinations to break chains of transmission and vaccinate all front-line workers to protect them.”
The trial will continue without randomization. What that means is that in Guinea, where there have been 3,786 cases and 2,520 confirmed deaths, every person that comes in contact with or that develops Ebola, and their secondary ring, will be offered the vaccine. Work performed in Gabon has also shown that the vaccine is safe for children and adolescents, so it will be offered to them too.
Just as it seemed Ebola was gone for now, the disease starts to rear its ugly head again; a 17-year old was killed a month after Liberia was declared free of Ebola.
(Photo: Frederick Murphy, AP)
Liberian authorities on Tuesday quarantined the Nedowein close to the capital of Monrovia, where the boy lived. The official announcement came quickly after.
“Liberia has got a re-infection of Ebola,” Tolbert Nyenswah, deputy health minister and head of Liberia’s Ebola response team, said in a press release.
Doctors are now trying to see how he got infected and what can be done to contain the infection. The area is not near Liberia’s borders with Sierra Leone and Guinea, neighboring countries that still have Ebola cases, so how the boy got the disease is still a mystery.
“The Ebola fight is not over but we must not lose hope,” said Liberia’s newly appointed minister of health, Dr. Bernice Dahn. She claimed to see the best in a bad situation, referring to the rapid testing and confirmation that the boy had the virus.
Ebola has claimed over 5,000 lives in Liberia and over 11,000 in West Africa. The disease is still lingering in Sierra Leone and Guinea, where the Ebola outbreak was first reported in March 2014. It was thought that Liberia was safe, but apparently, there’s still work to be done if we want to truly eradicate Ebola.
A new mobile Ebola test can detect the virus using a single drop of blood and reports a positive or negative result in under 15 minutes. When the ReEBOV test was applied in the field, it identified 100 percent of all infected patients who also got positive results with the lab test. Coupled with other recent advances in the fight against Ebola, like antiviral vaccines, the new test will help prevent another outbreak and hopefully contain the virus for good.
Image: Corgenix Medical Corp
Typically, when a person is suspected of being infected with Ebola, doctors perform a lab-based test called the PCR test. A full vial of blood is drawn from the arm, then placed in a machine that amplifies the genetic material which helps screen for the virus. This process lasts days, costs at least $100 per test, and of course requires a well equipped lab nearby. During this whole time, the potentially infected person needs to be quarantined until test results get back. Ironically, if the patient wasn’t infected until he was quarantined, he might very well be after.
The ReEBOV test developed by Colorado-based Corgenix works fundamentally different. Instead of screening for telltale genetic material, the test detects specific proteins made by the body in response to an Ebola infection. Within a couple of minutes after a couple drops of bloods are placed on a thin piece of paper, a line appears signaling either a positive or negative result. The whole test costs around $15 (now) and can be performed anywhere without expensive lab equipment or critical expertise required. Anyone can perform the test, even the potential infectee.
For two weeks in February, doctors tested 106 patients with suspected Ebola symptoms from Sierra Leone – one of the countries which was the hardest hit by Ebola – using the ReEBOV test and a classic PCR-based test, both in parallel. The ReEBOV test was also performed on 284 previously collected blood samples. Amazingly, the ReEBOV tests flashed positive for every single case in which the PCR-based test diagnosed Ebola. That makes it 100% sensitive. At the same time, it also showed some false positives which currently gives it a specificity of 92%, as reported in the journal The Lancet.
“We were surprised by the performance,” says Nira Pollock, an infectious disease doctor at Boston Children’s Hospital and an author of the new study. “It was more sensitive than I expected for a rapid antigen diagnostic test.”
It may be too soon to say, but I’ll take the fall: this is the cheap, portable and accurate Ebola test the world has been waiting for. Border crossings and hospitals can now use it fast and effectively, potentially saving thousands from the deadly disease that kills 9 out of 10 infectees.
“This test can be done in very austere environments, even off the back of a truck; it doesn’t require electricity or a sophisticated lab or an experienced technician,” points out Robert Garry, a virologist at Tulane University in New Orleans, Louisiana, who helped develop the technology the test is based on but was not involved in the new trial. “We need to be better prepared for the next Ebola outbreak and I think with this test we will be.”
“Having a rapid diagnostic test in the field would enable earlier identification of an Ebola outbreak,” adds Charles Chiu of the University of California, San Francisco, who was not involved in the study.. “And that could prevent further spread, especially in areas which really don’t have the resources to contain an outbreak.”
Previously, ZME Science reported how the Ebola virus binds to a “gateway” protein to infect humans. Without this protein, the virus can’t infect humans and scientists are now working on a potential drug or vaccine that can turn off the protein synthesis and effectively block Ebola infections. In the Guinea forest, trials are always underway to assess whether or not a Japanese antiviral drug made from the blood plasma of survivors can save lives. We’re still not done with Ebola, but it seems we’re winning.
A breakthrough study confirmed what scientists have long suspected: Ebola attaches itself to a singular, “gateway” protein to infect hosts. When mice were genetically engineered to lack the protein, these failed to become infected. Though extremely early, these promising results suggest Ebola outbreaks could be contained using vaccines that inhibit the protein either to stop the spread or prevent infection altogether. Nine out of ten infected Ebola patients die, and last year was the worst outbreak in history killing more than 11,000 people in Africa in official numbers, and likely twice as much in reality.
Ebola has an Achilles’ heel
Nowa Paye, 9, is taken to an ambulance after showing signs of the ebola. Image: Telegraph
In 2011, a virologist called Kartik Chandran at the Albert Einstein College of Medicine in New York City identified the protein in question, called NPC1, as a likely Ebola partner in crime. Chandran and colleagues found the protein rests in cell membranes and helps the virus slip past a cell’s defenses. Then, once inside the host organism it’s all free lunch. But they weren’t able to confirm their findings at the time. It remained a hunch.
In a new paper published in mBio, Chandran wanted to see what happened if the protein went missing, so they studied Ebola infection under three scenarios: 1) mice engineered with no copy of NPC1 2) mice with only one copy of the protein 3) mice with with two copies of NPC1, which is typical. The latter dropped like flies; mice with half the copies of the protein had a lower rate of infection and a lower rate of death versus the normal mice. The mice with no trace of the carrier protein came out healthy with no sign of Ebola infection.
“When we saw that you could not detect the virus at all, that was the ah-ha moment,” said John Dye, chief of viral immunology at the U.S. Army Medical Research Institute of Infectious Diseases. “I’ve looked at a lot of knockout mice over time and never seen that before.”
NPC1 is involved in transporting cholesterol through a cell. People lacking the protein develop Niemann-Pick disease which can lead to dementia and early death. However, a drug or vaccine that inhibits the protein for a short while, say a couple of months, could act as a shield for doctors going on life threatening missions in outbreak areas or massively deployed in those areas where the local population is at risk. For instance, in Guinea dead bodies are moved around using public transportation. It’s superfluous to mention how wrong this is.
“What the data suggests is that people who are completely deficient in it would never know they had been exposed [to Ebola], vs. having a single copy, those people may become sick, but probably would have a subclinical infection; they might not go to the hospital,” said co-first author Andrew Herbert, senior research scientist in the viral immunology branch of the U.S. Army Medical Research Institute of Infectious Diseases.
One could also imagine a situation where it could be used as a prophylactic, where a doctor who’s going into a very high risk clinic for a month or two could take it preventatively,” Dye said. “It’s very important when we’re asking doctors to risk their lives to provide care to provide some level of protection.”
According to Dye, a FDA-approved drug wouldn’t be ready for 5-10 years, but given emergency use there’s hope it could ready in 1-2 years.
A new study has found that as the climate continues to warm, we will be dealing with more infectious and parasitic diseases. Ultimately, we’ll have to face numerouse separate epidemics caused by climate change, researchers say.
Image via WHO.
It seems like with climate change, it’s more an issue of what gets us first – will it be the drought, the rising sea levels or… the diseases? Daniel Brooks, an eminent zoologist from the University of Nebraska-Lincoln’s Harold W. Manter Laboratory of Parasitology says that outbreaks like the recent Ebola epidemic will become more and more common as the climate continues to warm. Professor Brooks says it will be ‘the death of a thousand cuts’ with society unable to keep up with the speed of disease as it spreads throughout the world – it won’t be one major outbreak, but several smaller ones.
“It’s not that there’s going to be one ‘Andromeda Strain’ that will wipe everybody out on the planet,” Brooks said, referring to the 1971 science fiction film about a deadly pathogen. “There are going to be a lot of localized outbreaks putting pressure on medical and veterinary health systems. It will be the death of a thousand cuts.”
“Over the last 30 years, the places we’ve been working have been heavily impacted by climate change,” Brooks explained in an interview last week. “Even though I was in the tropics and he was in the Arctic, we could see something was happening.”
Changes in climate also allow parasites and parasite hosts to migrate to different areas. For example, some lungworms in recent years have moved northward and shifted hosts from caribou to muskoxen in the Canadian Arctic, something which was previously considered impossible.
“Though a parasite might have a very specialised relationship with one particular host in one particular place, there are other hosts that may be as susceptible,” Professor Brooks said. “West Nile Virus is a good example of this phenomenon – no longer an acute disease problem for humans or wildlife in North America, it nonetheless is here to stay,” he said.
This is the so-called “parasite paradox”. In time, both parasites and hosts become more adapted to each other and become better at fighting each other, so a type of stalemate is reached. But Brooks believes that parasites will break the equilibrium first, mutating into more dangerous versions. In order for society to maintain the upper hand, there needs to be a tight collaboration between veterinarians, public health officials, and biologists, says Brooks. For example, becoming aware of the way non-human carriers of a pathogen behave and are distributed could lead to better-informed public health strategies. But the problem remains that we are not leading this fight – we’re simply reacting.
“We have to admit we’re not winning the war against emerging diseases,” Professor Brooks said. “We’re not anticipating them. We’re not paying attention to their basic biology, where they might come from and the potential for new pathogens to be introduced.”
The great apes are suffering greatly from Ebola too – gorillas and chimps are facing the greatest threat ever, after Ebola has wiped out a third of the populations since the 1990s.
Ebola and great apes
Chimps and gorillas are also threatened by Ebola. Image via National Geographic Expeditions.
It’s easy to forget just how similar we are to apes and chimps. We share 94% of our DNA with chimps, and these two species are the closest living evolutionary relatives to humans, sharing a common ancestor with humans about four to six million years ago. Considering how similar we are, it should be no surprise that Ebola affects them.
In fact, the disease is much more dangerous for them than it is for us, with mortality rates of 95% for gorillas and 77% for chimpanzees, compared to about 50% in humans. The Ebola outbreaks are infrequent, but when they do strike, the effects are devastating. A study from 1994 found that a single Ebola outbreak wiped 25% of the chimps in a small population. But things got a lot worse in 1995, when 90% of gorillas in a national park in Gabon were killed. The problems continued throughout the 2000s, and in 2002-2003 another outbreak killed 5,000 gorillas in the Democratic Republic of Congo.
When you consider that there are under 100,000 gorillas in the wild, that’s a pretty big deal; and Ebola shows no signs of stopping. When you also consider that great ape populations are threatened by poaching and habitat destruction, the picture becomes much bleaker. The lack of habitat means that more individuals will come into contact with each other and are therefore much more likely of transmitting the disease.
Without aggressive investments in law enforcement, protected area management and Ebola prevention, the next decade will see our closest relatives pushed to the brink of extinction.
So far, he seemed to have been right.
An Ebola vaccine exists for great apes but…
Image via Babies Wild Animals.
Here’s where things get even more complicated. A vaccine for Ebola already exists for chimps and gorillas… but we can’t implement it, because testing on chimps is illegal. Across the European Union, where the vaccine was developed, it’s illegal to test drugs on chimps, even if the end result would greatly help them… so one can only wonder whether an exception should be made in this case. Talk about irony.
The US is the only developed country where testing on chimps is still allowed, which is ironic in its own way, but that’s a different story. But even the US is starting to shut down its chimp labs,
In the long term, conservation efforts aimed at restoring forest habitat could also help curb the spread of the virus, but a vaccine could work wonders here. Hopefully, a satisfying solution will be found, helping and protecting great ape populations from the threat of Ebola.
The World Health Organization reports a drop in the Ebola cases in the three Western African countries hit most by the disease. However, as farmers abandon their fields in the infected areas, a new problem seems to emerge: a food crisis.
Many agricultural fields have been abandoned as people retreat from Ebola. Image via World Bank.
Liberia only reported 48 cases in the past three weeks, but Sierra Leone is still struggling, with 769 new cases over the past 21 days. But even that is a decline compared to previous months.
“Sierra Leone has now reported a decline in case incidence for the second week running, and recorded its lowest weekly total of new confirmed cases since the week ending 31 August 2014,” WHO said.
This is not the first Ebola outbreak ever, but it’s the first time over 500 people were infected in one outbreak. The official number of infections is 21,261, though the likely number is much higher. However, as the number of Ebola cases seems to dwindle down, a new problem starts to emerge – a food shortage.
The International Fund for Agriculture Development (IFAD), a UN body that finances agriculture in poor countries has warned that if quick action isn’t taken soon, a food crisis is set to take place in the area. As early as September 2014 the Liberian government reported that large parts of the rice crop could not be harvested because of a shortage of labor. People are abandoning the infected areas – and for good reason.
“In Sierra Leone, we have information that up to 40% of farms in the hardest-hit areas have been abandoned,” IFAD President Kanayo F. Nwanze told Africa Renewal. In Guinea, similar disruptions in population movements have had “devastating effects on food production and exports”.
Agriculture is one of the main drivers of the West African economy, contributing up to 40% to the total economy. It’s also the main form of subsistence for the poorest people, who have no other way of supporting themselves.
It’s estimated that for the 90,000 households in dire need of help, some $30 million would be needed to alleviate the effects of the upcoming crisis.
The WHO says that the government’s lack of action is adding much to shape the Ebola epidemic ravaging through West Africa and threatening the entire planet. The situation became more serious, and the WHO has released a document demanding for more action if we want to control this epidemic and future ones.
Image via CDC.
The WHO has manned up and took a big part of the blame for not implementing containment programs fast enough. According to a report, there are over 21,000 cases which killed over 8,000 people – though the number is likely a gross underestimate. But WHO also points the finger at world governments; after receiving reports from the over 30 nations which are members of WHO’s executive board, the agency condemned world governments that had been responsible for imposing International Health Regulations in public health risk areas by closing borders as well as stopping who came from affected countries.
To improve and expand response capacity, the organization addresses the need for having enough of the right experts on its regular staff and for expanding partnerships in surge situations, such as the Global Outbreak Alert and Response Network (GOARN). The WHO is not fit to handle such large scale problems; they only have a skeleton staff to handle logistics. However, anthropologists to advise on how to handle interventions in different cultures are pretty much lacking from the organization.
The WHO wrote five proposals that would enable them to handle future health emergencies, but all of them require some outside help. A bigger budget is required to address rapid response scale-ups when needed, as well as a special “emergency fund”. Many countries are not able to offer a good enough response to an epidemic, and some countries, especially in Western Africa, lack even the minimum requirements for a response; many areas lack even basic hygiene.
Ebola was declared an epidemic on 8 August 2014, with the WHO director saying:
“Countries affected to date simply do not have the capacity to manage an outbreak of this size and complexity on their own. I urge the international community to provide this support on the most urgent basis possible.”
While the international community did react and helped, the reaction simply wasn’t strong enough, WHO concludes. The most affected countries were the ones from Western Africa – Guinea, Liberia and Sierra Leone.