Trachoma in the Northern Territory of Australia, 1940-1986

All known surveys of the prevalence of trachoma in the Northern Territory from 1940 to the present were reviewed. The crude (overall) prevalence rates for trachoma were calculated from the results of those surveys which involved whole Aboriginal communities. When three-or-more surveys had been conducted in a community over a period of 10 years or more, the results were plotted against the year of the survey. In most communities in the north of the Northern Territory (the "Top End"), the prevalence of trachoma appeared to have increased dramatically between 1950 and 1955 and then to have declined substantially at a rate of 2% per annum. This fall occurred before the mass-treatment programmes of the late 1970s and its most likely explanation is the improvement in living conditions. In five- to 10-years' time, trachoma may have disappeared completely from these communities. In most Central Australian communities, the prevalence of trachoma appears to have been constant or even to have increased. If social conditions were to begin to improve in Central Australian communities this year, and if those communities were to show the same response rates as in the Top End communities, then it could be well into the next century before the prevalence of trachoma there falls to the low rates of the Top End. This should be an impetus for social change in Central Australia; however, there might be a case for medically based control programmes in Central Australia, at least in the short term.