Coexistence of Philodina roseola (Rotifera: Bdelloidea) with larvae of Aedes aegypti in India.

The vector mosquitoes, Aedes aegypti and Aedes albopictus of dengue and Chikungunya fever are closely associated with human habitations and adapted to feed on human blood. They undergo larval and pupal development in natural and artificial freshwater collections in the urban and peri-urban environment. Although reports are available about the feeding behaviour of the thriving mosquito larvae, much information is still required to understand the successful survival of Aedes mosquitoes in small and temporary water collections.

Description of a new species, Toxorhynchites (Toxorhynchites) tyagii (Diptera: Culicidae), from Nilgiri hills, Western Ghats, southern India.

Specimens of Toxorhynchites (Toxorhynchites) tyagii, sp. n., were collected from the fringe areas of Gudaloor town, Ooty in the Nilgiri hills at an altitude of 1000 m above sea level in Western Ghats ranges in southern India during October 2011 and from Darjeeling ranges in the northern hilly region of Raymatang TG in Jalpaiguri district, West Bengal, in eastern India during February 2012.

The treatment of visceral leishmaniasis (kala-azar) in India: no obvious signs of long-term success.

In India, the eastern state of Bihar is particularly badly affected by visceral leishmaniasis (VL). It was in Bihar in the 1980s that the first clear signs of resistance to pentavalent antimonials, which had then been the standard antileishmanial treatment for several decades, were observed. New drugs and new formulations of old drugs have since been developed for the treatment of VL.

Impact of ivermectin drug combinations on Pediculus humanus capitis infestation in primary schoolchildren of south Indian rural villages.

Background: Antifilarial drug combinations including ivermectin provide antifilarial activity with ancillary benefits on intestinal helminths and ectoparasites, such as chiggers and lice. The impact of single oral dose of antifilarial drugs, viz; (1) diethylcarbamazine (DEC) alone, (ii) DEC + albendazole (ALB), (iii) ivermectin (IVR) + DEC and (iv) IVR + ALB, was determined, on the head louse (Pediculus humanus capitis) in primary school children in a rural community in south India.

Methods: Primary school children (n = 534) of age 6-10 years from four villages of South India were examined for the presence of head lice before and after single dose of DEC + ivermectin drug combination.

Larvicidal efficacy of various formulations of Bacillus sphaericus against the resistant strain of Culex quinquefasciatus (Diptera: Culicidae) from southern India.

Use of Bacillus sphaericus Neide (Bs) as potential biolarvicide in developing countries is limited due to development of resistance by target mosquitoes. Efforts are taken to look for appropriate formulations or combination of Bs to prevent or delay resistance problem. Here, we report the efficacy of a formulated Bs product to kill Bs resistant Culex quinquefasciatus Say larvae.

Longitudinal studies of Japanese encephalitis virus infection in vector mosquitoes in Kurnool district, Andhra Pradesh, South India.

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.

Host feeding pattern of Japanese encephalitis virus vector mosquitoes (Diptera: Culicidae) from Kuttanadu, Kerala, India.

Identification of blood meals of vector mosquitoes is an important tool in the epidemiological investigations of vector-borne diseases. The blood meals of three mosquito species involved in the transmission of Japanese encephalitis virus (JEV) from the Kuttanadu area, Kerala, were determined using the agarose gel diffusion technique. A total of 4959 blood smears belonging to Culex (Culex) tritaeniorhynchus Giles (3273), Cx.

Impact of single dose of diethylcarbamazine and other antifilarial drug combinations on bancroftian filarial infection variables: assessment after 2 years.

The impact of single dose mass drug administration of diethylcarbamazine (DEC), DEC with albendazole (ALB), and ivermectin (IVR) with albendazole, was examined on the human bancroftian filarial infections in village scale trials in south India, from a follow-up study after 2 years. The treatment arms administered with DEC alone and DEC+ALB demonstrated long-term benefits in reducing microfilaraemia significantly (P<0.05), while antigenaemia reduction was negligible.

Natural survivorship of immature stages of Culex vishnui (Diptera: Culicidae) complex, vectors of Japanese encephalitis virus, in rice fields in southern India.

The development and survival of immatures of Culex vishnui (Diptera: Culicidae) complex, vectors of Japanese encephalitis virus, were studied in transplanted rice, Oryza savita L., fields during three crop growing seasons. The total duration of development from the first instar to adult emergence varied from 6 to 8 d.

Field- and laboratory-based active dengue surveillance in Chennai, Tamil Nadu, India: observations before and during the 2001 dengue epidemic.

Background: Dengue cases are reported every year in the city of Chennai, Tamil Nadu, India. Since April 2001, longitudinal field- and laboratory-based active dengue surveillance has been carried out in Chennai to study dengue trends.

Method: A serologic survey of people in Chennai using the hemagglutination inhibition test (HIT) was performed to determine evidence of prior exposure to dengue virus infections.

Japanese encephalitis virus (JEV) is an important cause of encephalitis among children in Cuddalore district, Tamil Nadu, India.

Background: Japanese encephalitis (JE) is endemic in Cuddalore district, Tamil Nadu (TN), Southern India. The reports of JE cases from the local hospitals did not reflect the actual disease burden. It is likely that these cases were attending the nearby referral hospitals, for want of better treatment facilities.

Sustainability of soil-transmitted helminth control following a single-dose co-administration of albendazole and diethylcarbamazine.

We evaluated the long-term impact of single-dose diethylcarbamazine plus albendazole combination therapy with that of diethylcarbamazine alone on the control of soil-transmitted helminths (STH) in 2 blocks (revenue units) of Villupuram district, south India, as part of an ongoing mass drug administration (MDA) campaign for the elimination of lymphatic filariasis in 2001. The prevalence and intensities of STHs were studied in 287 children, aged 9 and 10 years (136 in the combination therapy cohort and 151 in the diethylcarbamazine alone cohort), using the Kato-Katz technique to examine stool samples at 4 time-points (baseline, and 3 weeks, 6 months and 11 months after MDA). The combination therapy showed long-term efficacy against STHs and the magnitude of control remained at a moderate and significant level for 11 months after MDA compared with the moderate gains of diethylcarbamazine alone.

Japanese encephalitis in Kerala, south India: can Mansonia (Diptera: Culicidae) play a supplemental role in transmission?

A 2-yr entomological study was carried out in Kerala, south India, to identify the mosquito vectors of Japanese encephalitis (JE) virus and to determine their seasonal abundance and infection. In total, 150,454 mosquitoes belonging to five genera and 18 species were collected from vegetation surrounding cattle sheds and pigsties in villages at dusk. Culex tritaeniorhynchus Giles (66.

Impact of two annual single-dose mass drug administrations with diethylcarbamazine alone or in combination with albendazole on Wuchereria bancrofti microfilaraemia and antigenaemia in south India.

A two-arm community-based lymphatic filariasis elimination trial is being carried out in Tamil Nadu state, India to assess the effect of 2 annual single-dose mass drug administrations of diethylcarbamazine + albendazole (DEC + ALB) on microfilaraemia and antigenaemia in one arm, and diethylcarbamazine(DEC) alone in the other arm. In a cross-sectional survey at each time-point, 450-650 subjects in childhood (2-9 years old) and young adulthood (10-25 years old) were screened from each treatment arm. After 2 annual mass drug administrations, microfilaraemia prevalence in the 2-drug arm was reduced by 54% and 62% in the 2-9 year old and 10-25 year old groups respectively; and corresponding figures for the single-drug arm were 26% and 37%.

The role of urea in the oviposition behaviour of Japanese encephalitis vectors in rice fields of South India.

The effect of urea on the oviposition behaviour of culicine vectors of Japanese encephalitis was studied in rice fields. Gravid females had a strong preference for oviposition in urea treated areas in rice fields, while no such preference was exhibited in untreated areas. The egg laying declined in the area where urea treated water surface had a mechanical barrier, which allowed volatile fractions to escape, but prevented contact with the water.

Dengue disease spectrum among infants in the 2001 dengue epidemic in Chennai, Tamil Nadu, India.

An investigation in a referral pediatric hospital has indicated that during a recent dengue outbreak in Chennai, Tamil Nadu, India, dengue in infancy constituted 20% of total dengue virus infections with low mortality rates in this hospital. In developing countries, strengthening of dengue management capabilities at hospitals can prevent dengue-related deaths in infants.

Longitudinal studies in South Indian villages on Japanese encephalitis virus infection in mosquitoes and seroconversion in goats.

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.

The influence of the mass administration of diethylcarbamazine, alone or with albendazole, on the prevalence of filarial antigenaemia.

The current Indian campaign for the elimination of lymphatic filariasis is largely based on mass drug administration (MDA). As part of this campaign, villagers in the Tirukoilur and Mugaiyur 'blocks' (i.e.

Efficacy of co-administration of albendazole and diethylcarbamazine against geohelminthiases: a study from South India.

The efficacy of single-dose combination drug therapy with diethylcarbamazine (DEC) plus albendazole (ALB), and single-drug therapy with DEC alone against geohelminths was compared as part of a mass drug administration (MDA) for elimination of filariasis. This study was conducted in two blocks of Villupuram District of Tamil Nadu State, India, covering a population of 321 000 including about 100 000 children 1-15 years of age. Prevalence and intensity of geohelminth infection were determined by the Kato-Katz technique immediately before and 3 weeks after the MDA.