The vector of filariasis in Djakarta and its bionomics

The authors present the results of an investigation, carried out in 1956-57 in the Rawasari district of Djakarta, to determine the vector of Bancroftian filariasis and to study its bionomics.Culex pipiens fatigans was the only species found to harbour the larvae of Wuchereria bancrofti in the area surveyed, and even in this mosquito the infection rate was very low. Among 24 271 C. p. fatigans dissected, the rate of infection with larvae of all stages was 1.8% and the rate of infection with larvae of the mature (infective) stage was 0.3%. It was established, however, that transmission occurred throughout the year, with a maximum in September. The density of larvae of all stages per dissected mosquito was 0.12 and that of the infective-stage larvae per dissected mosquito was 0.014. The potential transmission index was calculated to be 0.26.As to the bionomics of C. p. fatigans in Rasawari district, the study revealed that the density of mosquitos was highest in July and August, that mosquito-nets, clothes, hanging objects and furniture were the preferred resting-places, and that feeding took place mostly after midnight.