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Background: Climate change and associated increases in climate variability will likely further exacerbate global health disparities. More research is needed, particularly in developing countries, to accurately predict the anticipated impacts and inform effective interventions. oBjectives: Building on the information presented at the 2009 Joint Indo-U.S. Workshop on Climate Change and Health in Goa, India, we reviewed relevant literature and data, addressed gaps in knowledge, and identified priorities and strategies for future research in India. discussion: The scope of the problem in India is enormous, based on the potential for climate change and variability to exacerbate endemic malaria, dengue, yellow fever, cholera, and chikungunya, as well as chronic diseases, particularly among the millions of people who already experience poor sanitation, pollution, malnutrition, and a shortage of drinking water. Ongoing efforts to study these risks were discussed but remain scant. A universal theme of the recommendations developed was the importance of improving the surveillance, monitoring, and integration of meteorological, environmental, geospatial, and health data while working in parallel to implement adaptation strategies. conclusions: It will be critical for India to invest in improvements in information infrastructure that are innovative and that promote interdisciplinary collaborations while embarking on adapta­tion strategies. This will require unprecedented levels of collaboration across diverse institutions in India and abroad. The data can be used in research on the likely impacts of climate change on health that reflect India's diverse climates and populations. Local human and technical capacities for risk communication and promoting adaptive behavior must also be enhanced. [ABSTRACT FROM AUTHOR]

Poplars are affected by a large number of foliar pathogens in nurseries and in the field, which result in biomass reductions. Management of these diseases is essential to minimise losses. During field surveys between 2008 and 12, an unrecognized leaf spot disease was observed on several commercial clones of P. deltoides (G-48, Udai, WSL-22 & WSL-39). The pathogen was identified as Curvularia eragrostidis. Pathogenicity was proven on all host clones. This paper is the first report of the pathogen affecting poplars. [ABSTRACT FROM AUTHOR]

Resistance to chloroquine (CQ) in Plasmodium falciparum is one of the main causes of the wide-spread resurgence of malaria in India and a challenge to the effective control of the disease. In the pilgrim centre of Rameswaram Island, malaria has persisted despite the various control measures undertaken over the years. When CQ resistance in Rameswaram was investigated in vivo, recrudescent parasitaemias were observed in 25 (58%) of the 43 study subjects who were given CQ and completed follow-up, all occurring between days 10 and 28 (late treatment failures). The results of the msp1, msp2 and glurp genotyping of paired samples of P. falciparum, collected on day 0 and the day of recrudescence from 23 of the apparent treatment failures, indicated that 21 (91%) of the 23 were probably true treatment failures. All of the paired samples harboured parasites with the K76T mutation in their pfcrt genes, and subsequent sequencing of nine day-0 samples revealed the SVMNT haplotype in all nine. This is the first report of in-vivo drug resistance in P. falciparum from Rameswaram Island. Such resistance, which is probably the result of the indiscriminate use of CQ and/or the import of malaria from mainland India, warrants a change in the drug regimen used locally for the first-line treatment of uncomplicated, P. falciparum malaria, to make treatment more effective and slow the development and spread of more foci of CQ resistance. [ABSTRACT FROM AUTHOR]

Anopheles annularis is widely distributed mosquito species all over the country. An. annularis has been incriminated as a malaria vector in India, Sri Lanka, Bangladesh, Myanmar, Indonesia, Malaysia and China. In India, it has been reported to play an important role in malaria transmission as a secondary vector in certain parts of Assam, West Bengal and U.P. In Odisha and some neighbouring countries such as Sri Lanka, Nepal and Myanmar it has been recognised as a primary vector of malaria. This is a species complex of two sibling species A and B but the role of these sibling species in malaria transmission is not clearly known. An. annularis is resistant to DDT and dieldrin/HCH and susceptible to malathion and synthetic pyrethorides in most of the parts of India. In view of rapid change in ecological conditions, further studies are required on the bionomics of An. annularis and its role in malaria transmission in other parts of the country. Considering the importance of An. annularis as a malaria vector, the bionomics and its role in malaria transmission has been reviewed in this paper. In this communication, an attempt has been made to review its bionomics and its role as malaria vector. An. annularis is a competent vector of malaria, thus, due attention should be paid for its control under the vector control programmes specially in border states where it is playing a primary role in malaria transmission.

The study was carried out for evaluation of various activities of malaria control programme in five different tribal and malaria endemic Primary Health Centres of Dumka district (Jharkhand) during 2007-08. A total of 321 houses of 18 villages were surveyed on use of indoor residual spray (IRS) and insecticide-treated bed nets (ITN) and other activities as tool for vector control and interrupting the transmission of malaria. Out of 690 living rooms and 343 verandahs examined, IRS with Dichlorodiphenyl-trichloro-ethane (DDT) was done only in 16.23% living rooms and 64.72% verandahs. Refusal rate of IRS in living rooms was 81.93% due to lack of knowledge regarding the importance of IRS, no prior information to villagers, houses locked, reluctance to remove domestic articles, dislike of smell of DDT spray. Compliance rate of ITN uses was 71.66% during the night, which might be a factor for decline in malaria cases in the study area. Various important components of the programme, viz. surveillance and compliance to treatment activities, use of rapid diagnostic test kits (RDKs), involvement of accredited social health activist (ASHA's) and fever treatment depots (FTDs), laboratory activities, adult mosquito collection, other activities like constitution of village health sanitation committee, information education and communication activities, capacity building, use of larvivorous fishes, supervision of IRS etc. require much strengthening. However, 100% community acceptance was recorded for ITN in the villages surveyed. In addition, an entomological study was carried out for information on prevalence of mosquito species in this area to find out effectiveness of IRS activities. Eleven anopheline species, including three malaria vectors i.e., An. culicifacies, An. stephensi, An. fluviatilis, An. annularis, An. subpictus, An. nigerrimus, An. pallidus, An. aconitus, An. vagus, An. jamsii and An. splendidus were collected from cattle and human dwellings.

Entomological survey was carried out in different localities of Koderma district of Jharkhand with a view to study the prevalence, distribution and stratification of areas for Aedes mosquito species. A total of 233 houses were covered during house to house larval and adult survey. Aedes breeding could be detected in 157 houses. In all, a total of 942 domestic water containers were searched, out of which 461 were found positive. The overall house index(HI) container index(CI) breteau index(B1) and pupal index(PI) were 67.38%, 48.94%, 197.85% and 79.4%, respectively. The survey revealed that Aedes aegypti Linnaeus and Aedes albopictus Skuse are well established in Koderma with most of the areas showing high adult and larval indices. The preventive strategy needs to be directed towards minimizing the breeding potential of Aedes and water management practice by individuals along with implementation of urban bye-laws as well as IEC activities to contain Aedes breeding in future.

The epidemiological and entomological investigations were carried out in 18 tribal villages of Godda district of Jharkhand state revealed average slide positivity rate (SPR) 9.9% and slide positivity rate for Plasmodium falciparum (SfR) 5.0%, respectively. P. falciparum was the dominant parasite accounting 51.2 per cent of the total infections. All the villages are situated in the deep forest and forest fringes. A total of 416 blood slides were collected and examined. Out of which 41 slides were found positive for malaria parasite (21 positive for P. falciparum and 20 positive for P. vivax). All the positive cases were treated with Blister Packs of anti-malarial of chloroquine and primaquine as per NBVDCP schedule to prevent further transmission of malaria, which were available. Rapid diagnostic Kits were used selectively only on the recommendation of the Physician/Medical Officer. Results of house to house fever survey indicated the presence of high percentage of symptomatic carriers of malaria parasites in the local population and in our study Pf % is more than reported data by District Malaria Office, Godda district, Jharkhand. In entomological studies, for mosquito fauna with reference to both Anopheline, 11 species belonging to one genus Anopheles were collected and identified during the survey; among them some species were most prevalent. A total of 599 mosquitoes were recorded and average density of mosquitoes recorded was 13.19 in human dwellings and 86.11 in cattle sheds.

Hexane extract obtained from leaves of Eucalyptus citriodora Hook was tested against larvae of Anopheles stephensi Liston, Culex quinquefasciatus Say and Aedes aegypti Linn to assess its toxicity and growth inhibiting activity. The results showed better activity of hexane extract against larvae of An. stephensi Liston as compared to the larvae of Cx. quinquefasciatus Say and Ae. aegypti Linn. The LC50 values against IVth instar larvae of three species were 69.86, 81.12 & 91.76 ppm respectively after 24 hours and 26.7, 29.9 & 38.8 ppm respectively after 72 hours. At lowest concentration viz. 10 ppm, 73% larvae of An. stephensi Liston failed to emergence as adult mosquito while in Cx. quinquefasciatus Say and Ae. aegypti Linn only 10 & 6% larvae failed to emerge. Further observations showed some morphological abnormalities in same pupae which could not moult normally. These results clearly indicated growth inhibition effect of the hexane extract of Eucalyptus against mosquito larvae, particularly Anopheles species. Thus Eucalyptus citriodora Hook, which is commonly found in Northern India, has a great potential for the development of an eco-friendly herbal insecticidal product for control of mosquito breeding.

Fresh leaf extract of milkweed (Calotropis procera) showed larvicidal properties against mosquito larvae of Anopheles stephensi, Culex quinquefasciatus and Aedes aegypti. Methanolic extracts of the same plant were, however, more effective as larvicide. C. procera is a weed growing in uncultivated soils as well as in dry, arid zones in Indian subcontinent throughout the year. The results of this study suggest the utility of milkweed as potential technology for control of mosquito larvae.

Background & Objectives: In India, temephos and fenthion are used as larvicides in fresh and polluted waters. Since use of same insecticide may precipitate resistant, as an alternative bioefficacy of pirimiphos-methyl--an organophosphorus insecticide was evaluated against immatures of Anopheles and Culex species in different breeding habitats in District Ghaziabad (U.P.) and Goa., Methods: Laboratory bioassays were carried out using standard WHO procedure. LC50 and LC90 were calculated using Probit analysis. Abbott's formula was used to calculate per cent corrected mortality in laboratory exposures while, Mulla's formula was applied for calculating per cent reduction in mosquito immatures under field conditions., Results: Pirimiphos-methyl was found to be most effective against larvae of An. stephensi followed by An. culicifacies and Cx. quinquefasciatus. The LC50 and LC90 values against three species were 0.023, 0.032 and 0.04 ppm; and 0.045, 0.057 and 0.114 ppm respectively. In field, pirimiphos-methyl @ 200 g a.i./ha against Anopheles species and @ 300 g a.i./ha against Culex species can produce > 80% reduction in density of immatures up to one week in different habitats. Pirimiphos-methyl < 0.25 ppm is not toxic to fish., Interpretation & Conclusion: Pirimiphos-methyl is more effective against anophelines in clean water than culicines in polluted water. This larvicide should not be used at a concentration above 0.25 ppm in habitats harbouring the larvivorous fish.

Biocontrol potential of dragonfly nymph, Brachythemis contaminata Fabricius against the larvae of Anopheles stephensi, Culex. quinquefasciatus and Aedes aegypti was studied under laboratory conditions. It was found that dragonfly nymph had highest predation efficacy against An. stephensi followed by Cx. quinquefasciatus and Ae. aegypti. Feeding rate increased with decrease in prey size/stage. Analysis of data indicated that dragonfly nymphs have good predatory potential and can be used as a biological control agent for control of mosquito breeding.

Background & Objectives: Based on the reports of 139 fever related deaths in Jarwal primary health centre (PHC) of Bahraich district, Uttar Pradesh (UP) during April to September 1999, a study was undertaken to explore the possibility of outbreak of Plasmodium falciparum malaria in the area and reasons of outbreak., Methods: The study was undertaken during September-October 1999 in Bahraich district, UP. The study included a parasitological and an entomological survey. Blood slides from fever cases were collected and examined following standard procedures for detection of species and stage of parasite. The resting adult mosquitoes were collected from human dwellings and cattle sheds from selected villages. Susceptibility status of Anopheles culicifacies to 4 per cent DDT and 0.05 per cent deltamethrin was determined under laboratory conditions following the WHO procedure. In vitro drug sensitivity of P. falciparum to chloroquine was also estimated., Results: Overall slide positivity rate (SPR) was found to be 33.8 with a preponderance of P. falciparum (88.4%). There was an outbreak of Pf malaria in Jarwal and surrounding areas as well. Foci of P. falciparum malaria were found in Jarwal, Fakharpur and Hazoorpur PHCs around Kaisarganj PHC. In addition, P. falciparum cases, were also reported from Motipur and Tejwapur., Interpretation & Conclusion: Poor surveillance of affected areas resulting in low annual parasite incidence (API), lack of insecticidal spray in the currently affected PHCs as the API was less than 2 and development of resistance in P. falciparum to chloroquine were found as the possible reasons for the outbreak. It is recommended that surveillance be strengthened in all PHCs of Bahraich district to contain further extension of malaria in northeastern UP.

Biocontrol potential of Mesocyclops thermocyclopoides against first instar larvae of Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus was studied under laboratory conditions. It was found that M. thermocyclopoides had the highest predation efficacy against Ae. aegypti followed by An. stephensi and Cx. quinquefasciatus. There was a significant reduction in the predation efficacy of M. thermocyclopoides against Cx. quinquefasciatus in the presence of alternate food (p < 0.01). The cage simulation trial indicated that M. themocyclopoides has the potential to control Ae. aegypti breeding effectively in a container type of habitat.

The biology of a notonectid bug Enithares indica against immatures of Anopheline, Culicine and Aedine mosquitos was studied in the laboratory. The life cycle of the bug consists of the egg and five nymphal stages and takes about 64 +/- 1.54 days for completion. All stages of E. indica have good predatory potential. It can be used as a biological control agent in an integrated disease vector control program.

A feasibility study to identify mosquitogenic conditions in six study sites in and around Delhi (Bhalaswa lake, Nazafgarh drain, Seelampur lake, Sanjay lake, Okhla barrage and Hindon barrage) using Indian Remote Sensing Satellites was carried out. The water bodies with marshy areas, vegetation and human settlements were considered as environmental variables responsible for mosquitogenic conditions. Multidate IRS 1A and B, LISS-II satellite data were collected and analysed on Vax 11/780 computers. False colour composite (FCC) images were generated and land cover assessed using supervised classification based on ground truth training sets. Ground truth validation of satellite data was done on satellite pass dates. Concurrent monitoring of larval and adult mosquito density was performed by selecting sub-sites in each study site. The results indicate that mosquitogenic conditions can be identified (with limitation of resolution, i.e. 36.5 m) using FCC images and these images can be used as base maps of study sites. Characterization of study sites based on land cover was done from the view point of mosquitogenic conditions. Spatial changes in mosquito density vis-a-vis changes in environmental variables revealed positive correlation with water bodies and vegetation in some study sites.