WUCHERERIA BANCROFTI FILARIASIS IN SOUTH INDIA lilariasis: effect of age and gender. Transactions of the Royal Society of Tropical Medicine and Hygiene, 85,260-264. Pani, S. I’., Yuvaraj, J., Vanamail, P., Dhanda, V., Michael, E., Grenfell, B. T. & Bundy, D. A. P. (1995). Episodic adenolym- phangitis and lymphoedema in patients with bancroftian filariasis. Transactions of the Royal Society of Tropical Medicine and Hygiene, 89, 72-74. Partono, F. (1987). The spectrum of diseasein lymphatic lilari- asis. In: Filariasik, Ciba Foundation Symposium no. 127, pp. 15-31. Raccurt, C. P., Majon, M. & Hodges, W. H. (1984).Parasitologi- cal, serological and clinical studies of Wuchereria bancrojii in Limbe, Haiti. American Journal of Tropical Medicine and Hy- giene, 33, 11241129. Rajagopalan, P. K., Das, P. K., Subramanian, S., Vanamail, I’. & Ramaiah, K. D. (1989). Bancroftian filariasis in Pondi- cherry, South India. I. Pre-control epidemiological observa- tions. Epidemiology and Infection, 103,685-692. Rao, C. K., Rama Prasad, V. V. N., Narasimham, M. V. V. L., Sundaram, R. M., Dutta, K. K., Krishna Rao, Ch. & Venkatanarayana, M. (1982a).Prevalence and incidence rates of microfilaraemia and lilarial disease in the East Godavari district of Andhra Pradesh. Indian Journal of Medical Re- search, 75,23-27. Rao, C. K., Rama Prasad, V. V. N., Narasimham, M. V. V. L., Krishna Rao, Ch., Venkatanarayan, M. & Krishna Rao, P. (1982b). Impact of control measures on prevalence and inci- dence of bancroftian filariasis in East Godavari district of Andhra Pradesh. Indian Journal of Medical Research, 75, 515-520. Rao, C. K., Chandrasekharan, A. & Cherian, G. (1982~). Fre- quency and duration of acute filarial attacks in persons in Brugia malayi endemic community. Indian Journal of Medical Research, 75,813-815. Ravindranathan, T. C., Sethumadhavan, K. V. P., Roychoud- hary, S. P., Babu, C. S., Kanoujia, K. H., Narasimham, M. V. V. L. & Rao, C. K. (1980). Seasonal variation in microtilarae- mia (bancrofti) densitv and filarial disease. Yournal of Commu- nicable Diseases, 12,73177. Sabesan, S., Krishnamoorthy, K., Pani, S. P. & Panicker, K. N. (1992). Man-days lost due to repeated acute attacks of lym- phatic tilariasis. Trends in Life Sciences (India), 7, 5-7. Sasa, M. (1976). Human Filariasis. Tokyo: University of Tokyo Press,pp. 34-121. Sharma, R. V. S. N., Vallishayee, R. S., Mayurnath, S., Naray- anan, I’. R., Radhamani, M. P. & Tripathy, S. I’. (1987). Prevalence survey of filariasis in two villages in Chingleput district of Tamil Nadu. Indian Youma of Medical Research. 85. , , 522-530. Udonsi, J. K. (1988). Bancroftian filariasis in the Igwun Basin, Nigeria: an epidemiological, parasitological and clinical study in relation to the transmission dynamics. Acta Tropica, 45,171-179. VCRC (1994).Annual Report. Pondicherry, India: Vector Con- trol ResearchCentre. WHO (1992). Lymphatic Filariasis: Disease and its Control. Fifth Report of the WHO Expert Committee on Filariasis. Geneva: World Health Organization, Technical Report Series, no. 821. Received 25 April 1996; revised 26 June 1996; acceptedfor publication 2July I996 TRANSACTIONS OF THE ROYAL SOCIETY OF TROPICAL MEDICINE AND HYGIENE (1996) 90,643-644 Transovarial transmission of dengue 3 virus by Aedes aegypti Vinod Joshi, Manju Singhi and R. C. Chaudhary Desert Medicine Research Centre (Indian Council of Medical Research), Post Box no. 122, New Pali Road, Jodhpur- 342005, India Keywords: dengue 3 virus, Aedes aegypti, transovarial transmis- sion, India Dengue fever, associated with dengue haemorrhagic fever (DHF) is an important public health problem in the countries of south-east Asia and the western pacific (WHO, 1975). Although dengue associated with DHF has emerged in almost all the parts of India (BANERJEE, 1994) persistence of the virus in nature and in suscepti- ble human hosts could not be substantiated in the In- dian subcontinent by ILKAL et al. (1991), who were un- able to demonstrate transovarial transmission of dengue virus in mosquitoes in nature. In Jalore district of the arid western Rajasthan region, India, epidemic dengue has appeared twice, the first epidemic being reported in 1985. The virus strain dengue 3 has been reported to be active in the region (CHOUHAN et al., 1991). In the present paper we report investigations into the occurrence of transovarial transmission of dengue virus in Aedes aegypti. We have shown the presence of tran- sovarial transmission of the virus in nature as well as to the Fl progeny of experimentally virus-inoculated fe- male mosquitoes. This is the first report of transovarial transmission of dengue 3 virus in the Indian subconti- nent. A. aegypti is the principal vector of dengue virus in In- dia (RODRIGUES et al., 1972). Larvae of A. aegypti were collected from an endemic locality on the outskirts of Jalore town in India, each month from January to De- cember 1993 from domestic water containers. The larvae were reared in the laboratory and the emerged adults were kept for 3-4 d in Barraud cages with a supply of 4% glucose solution. Head squashes were prepared and ex- amined by the indirect fluorescent antibody test (IFAT) described by ROSEN & GUBLER (1974). High-titre im- mune rabbit serum raised against dengue virus was ob- tained from the National Institute of Virology, Pune, In- dia. Dengue 3 virus was also inoculated intrathoracically to 15 fully fed female A. aegypti, and their progeny in the Fl generation were subjected to the IFAT to detect any virus transmitted transovarially. The experimental mos- Table. Monthly rates of transovarial transmission of dengue virus in female Aedes aegypti Prevalence of Mean Mean relative infectiona temperature humidity Month No. No. (“Cl (%I (1993) examined infected Min. Max. Min. Max. January February March April May June July August September October November December t : :i 20 8 26.4 66 30.3 41 :: 32.6 40 4 (8.3%) 19.8 38.6 41 2: i NDb 25.1 25.3 43.6 40.9 41 38 4: 22.9 34.5 63 80 1: 0 21.8 21.5 35.2 35.2 56 54 74 12 : 28.4 37.8 53 2;: 27 58 i 10.8 6.1 296 31.7 47 56 ;: Total 388 22 (5.6%) - - - - aRateof infection with dengue 3 virus in adult female A. aegypti reared in the laboratory from field-collected larvae; deter- mined by the indirect fluorescent antibody test. bNot done.