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THE DISEASES − CHAPTER 4
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4.17 Trachoma
Introduction
Trachoma, caused by infection with Chlamydia trachomatis, accounts for about 3% of all
cases of blindness worldwide (1). Repeated episodes of inflammation and resolution
(precipitated by ocular C. trachomatis infection and occurring over years to decades) generate erate
conjunctival scar that can misdirect the eyelashes to rub on the surface of the eye and damage
the cornea.
Investment case
The global economic cost of trachoma from lost productivity has been estimated at
up to US$ 5 billion annually. 1 Such cost-of-illness estimates must be interpreted ted
with caution, especially when compared with those for other diseases, as they are highly hly
sensitive to methodological assumptions. Clearly, however, trichiasis surgery remains one
of the most cost-effective interventions to combat loss of vision. 2,3 At about US$ 40 per
surgery, it is also very affordable. An early estimate of the backlog of cases (almost 5 million
cases) suggested that US$ 200 million might be needed between 2011 and 2020. 4 This is a
conservative estimate of the backlog, relative to more recent regional estimates. Updated
country-specific estimates are expected in 2015. Thanks in part to a large donation of
azithromycin, preventive chemotherapy is also cost-effective. The pharmaceutical industry
has pledged to donate the medicines necessary to achieve elimination.
Using the latest data available on populations known or thought to be at risk, this report
updates estimates of the cost of delivering those medicines to the people who need them.
Once 80% coverage is achieved (at the latest by 2017) and maintained for a minimum of 3
years (a minimum of 5 years where baseline prevalence of active trachoma exceeds 30%),
mass treatment may be able to be stopped, although stopping decisions may need to be
made on a district-by-district basis. The investment target for preventive chemotherapy
(delivery excluding medicines) during 2015–2020 is about US$ 39 million (US$ 32–46
million) per year. The total amount for this period is slightly higher than an earlier estimate