Many tropical diseases are spread by parasites. Trachoma is different. It’s an infectious disease caused by a form of chlamydia bacteria that can blind its victims.
It spreads from person to person and especially child to child or mother to infant through discharges from the eye and nose. Flies also can carry it. The infection can even spread on soiled clothing or bedding where families dwell without adequate clean water and sanitation.
But it can be stopped or sharply curtailed with yearly administration of antibiotics. A global campaign is making headway in doing that.
Each year free antibiotics are given to tens of millions of people thanks to the U.S. Agency for International Development (USAID), the World Health Organization (WHO), foundations and other partners, including the American pharmaceutical company Pfizer, which donates its powerful antibiotic Zithromax (generic name azithromycin). Pfizer has donated 760 million doses since 1999.
Trachoma is a problem in 41 countries, mostly in Africa but also in Asia and Latin America. It’s blamed for the blindness or visual impairment of almost 2 million people.
Recently the WHO declared that Ghana and Nepal have eliminated trachoma as a public health problem, becoming the sixth and seventh countries to do so. The others are Cambodia, Laos, Mexico, Morocco and Oman. More are closing in on that goal.
The original goal of eliminating the threat by 2020 is unlikely. “Clearly we are behind schedule,” said Dr. Maria Rebollo Polo, who heads a WHO special project office in Brazzaville, Republic of Congo, working to eliminate neglected tropical diseases.
But it is still a triumph for public-private partnerships, with U.S. dollars and companies leading the way. “The American taxpayer has been the biggest investor in neglected tropical disease programs in the world,” said Rebollo, a public health physician from Spain.
USAID puts up $100 million a year and every taxpayer dollar leverages $26 in pharmaceutical donations, said the agency’s Rob Henry.
Some children and adults fight off repeated eye inflammations caused by exposure to the bacteria. But the cumulative effect of many such episodes can cause the upper eyelid to turn inward, scratch the eyeball, leave painful scarring and lead to irreversible blindness, the WHO says. In 2016 surgeons operated on a quarter-million people to correct the eyelid problem and 85 million were given antibiotics.
Working through national health ministries and community health workers, the antibiotics are administered in yearly campaigns. “These drugs are so safe that trained volunteers can administer them,” Rebollo said. The health teams emphasize the importance of facial cleanliness and other sanitary practices.
Some tropical diseases can be eradicated, but there will always be some trachoma cases because the bacteria occur naturally, Rebollo said. WHO considers trachoma’s threat to public health eliminated if fewer than 5 percent of children have inflamed eyelids and only one adult in 1,000 has the disease.
The Pfizer antibiotic is also used to treat other bacterial infections. A recent New England Journal of Medicine study found giving it twice a year sharply reduced child mortality from all causes in Niger, Tanzania and Malawi.
Another U.S. pharmaceutical giant, Merck, also plays a big role in the fight against tropical diseases. Merck began donating Mectizan, its drug for river blindness and lymphatic filariasis, 30 years ago. It provided 368 million treatments in 2017.