Temporal epidemiology of microfilaraemia among migrant workers entering Kuwait

BACKGROUND: There is paucity of published data on the microfilarial infection among migrants from endemic countries entering Kuwait. The primary objectives of this study were to use routine health surveillance data to i) to estimate the prevalence of microfilarial infection in migrant workers to Kuwait and ii) to determine the occurrence of any time trends in the proportions of microfilaria positives among these workers over the recent past. METHODS: Monthly aggregates of microfilaria thick slide test results obtained from routine health examinations of migrant workers conducted at the Ports and Border Health Division of Ministry of Health, Kuwait between January 1, 1992 and December 31, 2006, were available for trend analysis of these time series data. RESULTS: During the study period, the prevalence (per 100,000) of microfilaraemia positive migrant workers was 48 (1169/2449360). A third-order polynomial regression model of monthly proportions of microfilaraemic workers revealed a significant initial increase ([Formula: see text] = 2.976 (± 0.157); P < 0.001), followed by a significant declining trend ([Formula: see text] = -0.0358 (± 0.002); P < 0.001) and a slight but significant upward trend ([Formula: see text] = 0.0001 (± < 0.001); P < 0.001) towards the end of study period. CONCLUSION: This study showed a recent steady but apparently asymptotic decline in the prevalence of microfilarial infection in migrant workers from filarial endemic countries to Kuwait. This may reflect either changes in the socio-economic backgrounds of recent migrants or the effects of recently initiated mass drug administration programs carried out in the endemic countries of origin.