There have been organised trachoma control programmes in many endemic countries for decades, which have met with variable success. In 1998 the World Health Assembly resolved to eliminate blinding trachoma by the year 2020 
. To this end the GET2020 was formed, including representatives from the WHO, national blindness control programmes from endemic countries, nongovernmental organisations working in the field, industry, and academic institutions. The GET2020 alliance adopted the SAFE Strategy as its favoured approach to controlling trachoma 
. The four components of SAFE are surgery for trichiasis, antibiotics for infection, facial cleanliness, and environmental improvements to reduce transmission.
There is a growing body of published evidence supporting the clinical effectiveness of each component of the SAFE strategy 
. In the case of trichiasis surgery there are currently nine published randomised controlled trials investigating various aspects of management including the optimal type of operation, level of surgeon, where surgery should be done, and whether peri-operative antibiotic improves the outcome 
. However, there are major problems both with the outcome of surgery, with high trichiasis recurrence rates reported under operational conditions, and the effective delivery of the service on the ground in many endemic countries 
Over the last 60 y there have been many studies testing different antibiotics for active trachoma. The WHO currently recommends the use of either oral azithromycin (single dose) or topical tetracycline (twice daily for 6 wk). Both of these antibiotics have been demonstrated to be effective in clinical trials at reducing the prevalence of both active disease and C. trachomatis
. The clinical signs of active trachoma have a relatively low sensitivity for the identification of C. trachomatis
infection. In addition, C. trachomatis
has the potential to rapidly reemerge in communities where some infected cases are left untreated. Therefore, the current recommendation is for mass drug administration (MDA) of entire endemic communities to be conducted annually for several years, until the prevalence of follicular trachoma (TF) in children ages 1–9 y drops below 5% 
. It is likely that, with such a low threshold for treatment, very large numbers of uninfected people will be treated with antibiotic in order to catch all those harbouring infection. The evidence base supporting the effectiveness of face washing and environmental interventions in reducing trachoma is more limited 
. However, the historical epidemiology of trachoma strongly supports the view that general improvements in hygiene can have a profound long-term effect on this disease.
Several investigators have produced estimates of the cost-effectiveness of trachoma control programmes or individual components of the SAFE strategy. The only study evaluating the long-term cost-effectiveness of an entire national trachoma control programme was made by Evans and colleagues for Myanmar (Burma) over a 30-y period (1964–1993) 
. This programme predated the introduction the SAFE strategy; however, it contained several elements of today's trachoma control programmes: surgery, mass antibiotic distribution, and community education. During this period there was a marked decline in the disease in Myanmar. The overall cost-effectiveness of the programme was estimated at US
54 per case of visual impairment prevented. Two factors may have lead to an overestimate of the cost-effectiveness: (1) it was assumed that all the visual impairment from trachoma prevented was due to the activities of the programme, rather than to any underlying secular trend due to socioeconomic changes, (2) only the direct costs to the national programme were included.
Three analyses for the cost-effectiveness of trichiasis surgery have been produced, which consistently found it to be very cost effective. In the analysis of the Myanmar programme the average cost (over the 30-y period) per case of visual impairment prevented was estimated to be US
193, although in the last 10 y of the programme there was a marked rise in the cost-effectiveness of trichiasis surgery to US
41 per case of visual impairment prevented 
. The cost per HALY saved was on average US
10, dropping to US
3 for the final 10 y. In The Gambia the cost of surgery was estimated to be US
6.13 per operation (1998), whilst the estimated life-time loss of economic productivity was US
. In a separate analysis the cost-effectiveness of surgery was estimated for seven trachoma endemic world regions 
. The cost of trichiasis surgery was estimated to be about International Dollars (I
) 19 per case in Africa. It was estimated that if surgery was carried out on 80% of the current cases of trichiasis this would save 11 million DALYs globally each year. Surgery was found to be very cost effective with estimates ranging from I
13 to I
78 per DALY, depending on the region.
The cost-effectiveness of antibiotic treatment has also been considered in a number of analyses. In the evaluation of the Myanmar programme it was found that the cost of nonsurgical interventions (mostly antibiotic treatment) was US
47 per case of visual impairment prevented 
, which gave a cost-effectiveness of US
3 per HALY averted. This seems to be a remarkably low cost and there may have been some major methodological biases that attributed the vast bulk of the DALYs to the nonsurgical as opposed to the surgical components of the programme. In contrast, the more recent projection of the cost-effectiveness of trachoma control in seven world regions found antibiotic treatment to be relatively cost ineffective 
. For example in Africa the cost of mass antibiotic distribution of azithromycin to children aged 1–10 y was I
9,012 per DALY saved if the azithromycin had to be purchased at the standard cost price. Azithromycin is currently donated by the manufacturer, Pfizer Inc., to trachoma control programmes in 15 endemic countries. Even if the drug is donated, the authors concluded that costs remain high at I
3,922 per DALY. However, this study made a number of questionable assumptions that cast doubt on these figure. For example, the authors assumed that mass treatment would need to be given annually for 10 y, which is probably much longer than would be needed if high coverage levels are achieved. The effectiveness of mass azithromycin treatment is variable, although several studies have suggested that C. trachomatis
infection can be well controlled with one or two rounds of mass treatment 
. The authors further assumed that the reduction in trichiasis prevalence due to mass treatment would not be seen for 45 y, and that the proportionate reduction in trichiasis and blindness would be the same as the reduction in the prevalence of active trachoma seen after 10 y. It is not known how effective controlling C. trachomatis
infection will be on the development of the scarring sequelae in people who have previously been repeatedly infected, however it is anticipated that as the prevalence of infection drops so the drive to disease progression lessens. There are major logistical and financial obstacles, even with donated azithromycin to repeatedly conducting mass drug administration, especially in remote rural settings. In response to this there has been a move to try, where appropriate, to combine mass drug administration with azithromycin for trachoma with treatments for other NTDs.