Epidemiology of malaria outbreak (April/May, 1999) in Titabor Primary Health Centre, district Jorhat (Assam)

An investigation was undertaken of a malaria outbreak in the Primary Health Centre Titabor, district Jorhat, Assam during May / June 1999. The fever r ate in the community Since March 1999, was 44.4 per cent with an average ca se load of 2.5 per family. The fever cases peaked in the third week of May. Slide positive and slide falciparum rates in mass blood survey, in the stu dy village were 16.1 and 14.5 per cent respectively with 90 per cent infect ion of Plasmodium falciparum Males (PR 17.5%) suffered relatively more than females (SPR 14.7%). Malaria prevalence vas significantly less in individu als above 15 yr of age (SPR 11.0%) as compared to those below 15 yr (SPR 22 .9 %). Prevalence of malaria as well as mosquito densities in different clu sters of the village were inversely related to the distance from the forest ed Naga hills. Anopheles minimus and A. dirus were collected in good number s with comparatively higher densities of the former. Several factors like u nusual climatic conditions, inadequate surveillance, unsatisfactory laborat ory services and inadequate indoor residual insecticide spray were instrume ntal for the outbreak.