Tag Archives: neglected tropical disease

Myanmar eliminates trachoma, the world’s leading infectious cause of blindness

Trachoma is caused by the bacterium called Chlamydia trachomatis. In its early stages, trachoma causes conjunctivitis (pink eye) with symptoms appearing within five to 12 days of exposure to the pathogen. As the infection progresses, it causes eye pain and blurred vision.

World Health Organization (WHO) simplified system. (a) Normal conjunctiva, showing area to be examined. (b) Follicular trachomatous inflammation (TF). (c) Intense trachomatous inflammation (TI) (and follicular trachomatous inflammation). (d) Conjunctival scarring (TS). (e) Trichiasis (TT). (f) Corneal opacity (CO).

If left untreated, scarring occurs inside the eyelid leading to the eyelashes turning inward toward the eye (a condition called trichiasis). As the eyelashes scratch against the cornea, it becomes irritated and eventually turns cloudy and can lead to corneal ulcers and vision loss. Generally, it takes years before trachoma can cause vision loss. In the early stages of the disease, antibiotics are very effective but more advanced cases may need surgery to help limit further scarring of the cornea and prevent further loss of vision. A corneal transplant can help if the cornea is so clouded that vision is significantly impaired.

Trachoma is the leading infectious cause of blindness globally and has long been considered a major public health problem in the Southeast Asian nation, with the first Trachoma Control Project initiated in 1964 by the Ministry of Health and Sports, with support from WHO and the United Nations Children’s Fund (UNICEF). 

In 2005, trachoma was responsible for 4% of all cases of blindness in Myanmar. From 2010 to 2015, the annual period prevalence of blindness from all causes in the total population was very low in all regions and states, ranging from 0% to 0.023%. By 2018, this prevalence dropped to 0.008%. The WHO Weekly Epidemiological Record in July also reported the number of people at risk of trachoma has been reduced by 91% — from 1.5 billion in 2002, to 136.9 million in May 2020.

In order to eliminate trachoma as a public health problem, there is a WHO-recommended “S.A.F.E.” strategy which includes: Surgery for trichiasis, Antibiotics to clear Chlamydia trachomatis infection, Facial cleanliness, and Environmental improvement to reduce transmission. Community-based interventions also include improved access to water, sanitation and hygiene (WASH), and health education promoting behavior change to decrease transmission.

“This remarkable achievement reminds us of the importance of strong political commitment to implement integrated disease elimination measures, public engagement and disease surveillance,” said Dr. Mwelecele Ntuli Malecela, WHO Director, Department of Control of Neglected Tropical Diseases. “The new neglected tropical disease road map for 2021–2030, which will foster these processes globally, should allow us to anticipate more such success stories from countries using WHO-recommended strategies.”

Myanmar is the tenth country worldwide following Cambodia, China, Ghana, the Islamic Republic of Iran, Lao People’s Democratic Republic, Mexico, Morocco, Nepal, and Oman to reach this milestone. It remains a public health problem in 44 countries and is responsible for the blindness or visual impairment of an estimated 1.9 million people, most of whom are extremely poor. Regular post-validation trachoma surveys are also planned to provide post-validation surveillance. Successful validation of elimination of trachoma as a public health problem in Myanmar will encourage other health ministries and their partners to continue their efforts against this painful blinding disease.

Togo is the first African country to eliminate sleeping sickness

Togo, officially the Togolese Republic (République togolaise), a country in West Africa has received validation from the World Health Organization (WHO) for having eliminated human African trypanosomiasis or “sleeping sickness” as a public health problem, becoming the first country in Africa to reach this milestone. It gets its nickname ‘sleeping sickness’ because symptoms can include a disturbed sleep pattern.  

What is African sleeping sickness?

Sleeping sickness is caused by parasites that are transmitted by infected tsetse flies and is only found in 36 countries in sub-Saharan Africa. If left untreated sleeping sickness is almost always fatal. In 1995, about 300,000 cases were estimated to have gone undetected, with 60 million people estimated to be at risk of infection. In 2019, fewer than 1,000 cases were found.

Illustration of the life cycle of the trypanosome parasite that causes African sleeping sickness.
Image credit: Genome Research Limited

What are the two forms of sleeping sickness?

There are two forms of sleeping sickness. The first, due to Trypanosoma brucei gambiense, is found in 24 countries in west and central Africa and accounts for more than 98% of cases. The second form, due to Trypanosoma brucei rhodesiense, is found in 13 countries in eastern and southern Africa and represents the rest of cases. WHO and partners are targeting the elimination as a public health problem of the gambiense form of the disease from all endemic countries by 2030. Benin, Burkina Faso, Cameroon, Cote d’Ivoire and Ghana have started the validation process with the support of WHO.

How did Togo eliminate African sleeping sickness?

Togo has not reported any cases in the past 10 years. Togo’s achievement comes after more than two decades of sustained political commitment, surveillance and screening of cases. Beginning in 2000, the country’s public health officials implemented control measures. In 2011, the country established surveillance sites at hospitals in the cities of Mango and Tchamba, which cover the main areas at risk of the disease. Public health officials have since maintained heightened disease surveillance in endemic and at-risk areas. Neighboring countries are not at the same phase and so surveillance must continue to avoid a resurgence of this disease.

Togo first applied for certification of elimination of sleeping sickness in 2018 and a team of WHO experts studied the data, made recommendations and requested a revision by the country before giving their approval. A WHO-led global collaboration supported these efforts by facilitating the donation of medicines and resources from pharmaceutical companies, which helped strengthen local capacity and ensure the sustained availability of tools required to control the disease. Wiping out the gambiense form of sleeping sickness will require maintaining the commitment of endemic countries and of donors, as well as integrating control and surveillance activities into the regular health systems.