Treating trachoma

Trachoma is the leading cause of preventable blindness worldwide. The disease induces blindness through repeated infection of the causative organism Chlamydia trachomatis, writes Dr Iain Phillips

Chlamydia trachomatis
There are three main bacterial pathogens in the genus chlamydia. These are Chlamydia trachomatis, C psittaci and C pneumoniae. C psittaci causes psittacosis and C pneumoniae is known to cause respiratory tract infections including pneumonia.

There are 15 serotypes of C trachomatis and the pathology caused by the infection relates to the serotype. Trachoma is caused by serotypes A, B, Ba and C. The sexually transmitted disease caused by C trachomatis is caused by serotypes B, Ba and D to K. As well as causing infections such as urethritis and cervicitis, infection can lead to inclusion body conjunctivitis in both adults and neonates. Lymphogranuloma venereum is caused by serotype L. This is a disease of the genitalia, starting with the formation of a localised genital ulcer and inducing regional lymphadenopathy.