It takes two

Mass antibiotic treatment is having less impact than expected on the blinding ocular condition trachoma in regions such as Ethiopia. So UK and Australian researchers are proposing a new solution – hit the infection with a one-two punch.

The researchers – the London School of Hygiene and Tropical Medicine’s Matthew Burton and Monash University’s Manoj Gambhir and Amy Pinsent – have used computer modelling to test out a number of trachoma treatment scenarios.

They found a double-dose antibiotic strategy, where a second medication dose was offered two weeks after the first in combination with hygiene promotion, had the most potential to reduce the potentially blinding condition, caused when repeated eye infections led to eyelid distortion and corneal scarring.

The double-medication strategy could ensure even patients with high loads of the Chlamydia trachomatis bacteria at the first dose had their infection successfully treated and did not experience a re-emergent infection, according to the paper published in the journal BMC Medicine.

Dr Burton told OT that the commonly used antibiotic, azithromycin, stayed in the body at therapeutic levels for several days.

“[Two weeks] is a reasonable compromise between trying to hit the infection twice but also having a better chance of picking up those people in the community who missed the opportunity to take the first dose,” he said.

However, Dr Burton emphasised that complementary initiatives will work best. The models showed that promoting facial cleanliness and other hygienic environmental practices is essential for reducing the spread of the infection from person to person.

“It’s not just all about antibiotics … The modelling showed how profoundly important it is to get this right,” he highlighted.

The researchers are now seeking funding to run a small trial putting the findings of the model into practice, offering a double-dose of antibiotics to a trachoma-hit community. Alongside this, they would also trial a number of hygiene promotion tactics, Dr Burton said.

“We’ll be exploring a range of ideas around strategies to reduce transmission that might be impactful and achievable,” he explained.

The results will then be compared to the success rates of the standard trachoma control initiatives, Dr Burton said.