Publications (11)15.99 Total impact
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Article: Longitudinal studies of Japanese encephalitis virus infection in vector mosquitoes in Kurnool district, Andhra Pradesh, South India.
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ABSTRACT: A 4-yr (2002-2006) entomological study was carried out in Kurnool district, Andhra Pradesh state, south India, to identify the mosquito vectors of Japanese encephalitis virus (family Flaviviridae, genus Flavivirus, JEV). In total, 37,139 female mosquitoes belonging five genera and 18 species resting on vegetation were collected in villages and periurban areas at dusk. Mosquito species composition and pattern of JEV infection in mosquitoes varied in periurban and rural areas. In periurban area, Culex gelidus Theobald was abundant, making up 49.7% of total catch followed by Culex tritaeniorhynchus Giles (44.5%). In rural area, Cx. tritaeniorhynchus was predominant, making up 78.9% of total catch followed by Culex quinquefasciatus Say (10.8%), Anopheles subpictus Grassi (7.1%), and Cx. gelidus (1.1%). In light trap collections, Cx. gelidus and Cx. tritaeniorhynchus predominated in periurban and rural areas, respectively. Of 50,145 mosquitoes screened JEV isolations were made only from Cx. gelidus and Cx. tritaeniorhynchus. Based on high abundance and frequent JEV isolation, Cx. tritaeniorhynchus was found to be the principal vector in both areas, whereas Cx. gelidus plays a secondary vector role in periurban areas only.Journal of Medical Entomology 06/2009; 46(3):633-9. · 1.76 Impact Factor -
Article: Sero-entomological investigations on Japanese encephalitis outbreak in Gorakhpur division, Uttar Pradesh, India.
The Indian journal of medical research 04/2009; 129(3):329-32. · 1.84 Impact Factor -
Article: Japanese encephalitis in Gorakhpur Division, Uttar Pradesh.
The Indian journal of medical research 01/2009; 128(6):775-7. · 1.84 Impact Factor -
Article: Studies on dengue in rural areas of Kurnool District, Andhra Pradesh, India.
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ABSTRACT: A dengue case was reported for the 1st time in a rural area of Kurnool District, Andhra Pradesh, India. Entomological and serological investigations were carried out to determine the prevalence of dengue vectors and dengue virus. Aedes aegypti was recorded for the 1st time in rural areas of Andhra Pradesh. Breeding of Ae. aegypti was observed only in containers with nonpotable water. Cement cisterns and tanks, stone tubs, and clay pots were the major breeding habitats of Ae. aegypti. Larval indices for Ae. aegypti ranged as follows: house index 28-40%, container index 13-37%, and Breteau index 32-60. A serological survey indicated that humans in Kurnool District have been exposed to dengue virus infections. The potential threat of an outbreak of dengue fever in rural areas because of the prevalence of the vector (Ae. aegypti) and dengue virus is discussed.Journal of the American Mosquito Control Association 04/2004; 20(1):87-90. · 0.91 Impact Factor -
Article: Longitudinal studies in South Indian villages on Japanese encephalitis virus infection in mosquitoes and seroconversion in goats.
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ABSTRACT: Japanese encephalitis (JE) is endemic in Cuddalore district, Tamil Nadu, where Culex tritaeniorhynchus Giles was the major vector. We screened 45 100 adult female Cx. tritaeniorhynchus (902 pools) by enzyme-linked immunosorbent assay and isolated and confirmed JE virus (JEV) by using an insect bioassay system. We had 69 isolates of which 62 (90%) were identified as JEV. The average vector abundance per man hour for Cx. tritaeniorhynchus was 324.5 per month for the period June 1998-May 2000. The average minimum infection rate (MIR) per month in Cx. tritaeniorhynchus was 1.4 (range 0.0-5.6). Every year, a new batch of goats, 20 in the first year and 31 in the second year, born during the non-JE transmission period (January-June), aged <6 months and negative for haemagglutination inhibition (HI) antibodies were procured and placed in the villages as sentinels. Fortnightly, blood specimens were collected from these goats and tested for JE antibodies by HI test. Seroconversions (SCs) were recorded in 14 goats (70%) in the first year and 23 goats (74%) in the second year. JE HI antibody titres in goats were low (1:10-1:80) and these levels declined to undetectable levels in about 4 weeks following SCs. The time sequence of events indicated that four of five peaks of MIR in mosquitoes were followed 1-3 months later by peaks in the proportion of seroconverted goats. We suggest the screening of goats and cattle as a more feasible tool to stratify areas according to JE infection risk to the human population through the regular health system rather than screening mosquitoes using monoclonal antibodies, which is possible only in specialized laboratories.Tropical Medicine & International Health 03/2003; 8(2):174-81. · 2.80 Impact Factor -
Article: Vertical transmission of Japanese encephalitis virus in Mansonia species, in an epidemic-prone area of southern India.
Annals of Tropical Medicine and Parasitology 07/2002; 96(4):419-20. · 1.43 Impact Factor -
Article: Vertical transmission of Japanese encephalitis virus in Mansonia species, in an epidemic-prone area of southern India
Annals of Tropical Medicine and Parasitology 05/2002; 96(4):419-420. · 1.43 Impact Factor -
Article: A system for studying vector competence of mosquitoes for Japanese encephalitis virus.
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ABSTRACT: A method to infect mosquitoes with Japanese encephalitis virus (JEV) and to demonstrate virus transmission after an extrinsic incubation period is described. Using per oral feeding method infection rate as high as 90% could be achieved. Demonstration of transmission of the virus was achieved by allowing the infected mosquitoes to probe a suitable serum medium and testing the probed serum for virus. Both infection and transmission were demonstrated by using insect-bioassay.Indian journal of malariology 10/1998; 35(3):146-50. -
Article: A note on first isolation of Japanese encephalitis virus from Culex infula Theobald (Diptera:Culicidae).
The Journal of communicable diseases 10/1998; 30(3):199-200. -
Article: Virus isolation from wild-caught mosquitoes during a Japanese encephalitis outbreak in Kerala in 1996.
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ABSTRACT: Out of 5357 wild-caught mosquitoes in 163 pools tested for virus using antigen capture ELISA and an insect-bioassay (inoculation into Toxorhynchites splendens larvae and identification by IFA using JE virus-specific monoclonal antibody), 16 flavivirus isolations were made of which 12 (75%) were identified as JE virus. Of the 12 JE virus isolations, 7 were from Culex tritaeniorhynchus, 3 from Mansonia uniformis and 1 each from Ma. indiana and Anopheles subpictus. Four isolations from Mansonia species for the first time reported here are noteworthy.The Indian journal of medical research 08/1997; 106:4-6. · 1.84 Impact Factor -
Article: Natural vertical transmission of dengue viruses in Aedes aegypt in southern India.
Transactions of the Royal Society of Tropical Medicine and Hygiene 94(5):507. · 2.16 Impact Factor
