Agent can eliminate eye infection

As little as one dose of Pfizer Inc.’s Zithromax antibiotic could wipe out trachoma, the leading cause of infectious blindness in the developing world, according to a letter in the New England Journal of Medicine.
Annual treatment with Zithromax, also sold as the generic azithromycin, for three to five years may be unnecessary, researchers said. Three years after the second mass treatment of inhabitants at a small village in Tanzania, the infection caused by the bacteria Chlamydia trachomatis had been eliminated, research showed.
Trachoma puts as many as 500 million people in the world at risk of becoming blind. The World Health Organization currently recommends mass treatment with Zithromax for three years to stop the infection. The study, partly funded by New York-based Pfizer, suggests just one round of treatment may be enough in communities with moderate levels of infection.
“Had WHO recommendations on antibiotic use been followed, three or possibly five annual rounds of mass treatment would have been offered, whereas our data suggest that one round was sufficient,” said Anthony Solomon from the London School of Hygiene, in a research letter to the medical journal.
Solomon and colleagues in Tanzania treated 98 percent of the residents in Kahe Mpya, Tanzania, with Zithromax and gave a second dose two years later. Infection dropped to 0.1 percent two years after first treatment from 9.5 percent. Eye inflammation in children fell to 2.6 percent from 16 percent within 5 years after receiving the drug.
The World Health Organization introduced the SAFE strategy, which includes surgery to halt corneal damage, antibiotic treatment, face washing and environmental change such as access to water, to stop the spread of the disease. Pfizer donated the drug after the WHO said mass treatment with Zithromax could help eliminate trachoma.
About 3 million people are visually impaired or blind as a result of trachoma, which is spread from eye to eye by dirty hands or flies. The number of infected people dropped to about 43 million people in 2008 from about 100 million in 1996 according to the WHO’s estimates. National health programs, improvement of social conditions and Pfizer’s donation are helping eliminate the disease, the researchers said. •