Use of chemical pesticides is the current method for controlling sandflies. However, resistance is being developed in sandflies against the insecticide of choice that is DDT (dichlorodiphenyl trichloroethane). Botanicals have potential to act as an alternative to chemical insecticides as the crude extracts and active molecules of some plants show insecticidal effect to sandflies. This will lead to safe, easy and environment friendly method for control of sandflies. Therefore, information regarding botanicals acting as alternative to chemical insecticide against sandflies assumes importance in the context of development of resistance to insecticides as well as to prevent environment from contamination. This review deals with some plants and their products having repellent and insecticidal effect to sandflies in India and abroad. Different methods of extraction and their bioassay on sandflies have been emphasized in the text. Various extracts of some plants like Ricinus communis (Euphorbiaceae), Solanum jasminoides (Solanaceae), Bougainvillea glabra (Nyctaginaceae), Capparis spinosa (Capparidaceae), Acalypha fruticosa (Euphorbiaceae) and Tagetes minuta (Asteraceae) had shown repellent/insecticidal effect on sandflies. This review will be useful in conducting the research work to find out botanicals of Indian context having insecticidal effect on sandflies.

Background & objectives: The enzyme glutathione-s-transferases (GSTs) are associated with detoxification of DDT, as experimentally proved in Anopheles gambiae. Insect GSTs are classified into six classes and among them Delta and Epsilon class GSTs have been implicated in detoxification of organochlorine insecticides. Both Delta and Epsilon GSTs produce, in total, 24 transcripts that result in the production of corresponding enzyme proteins. However, the conventional assay estimates the level of total GSTs and relates to development of resistance to DDT. Hence, it would be more reliable to estimate the level of the specific class GSTs that shows higher affinity with DDT. This would also lead to design a specific molecular tool for resistance diagnosis. Methods: Of the 24 GSTs, computational models for 23 GSTs, which are available in Swiss-Prot database, were retrieved and for the remaining one, D7-2, for which no model is available in the data bank, a structural model was developed using the sequence of An. dirus B with a PDB ID of 1R5A as the template. All the models were docked with DDT in the presence of reduced glutathione. Results: The energy output showed that Delta, D6 has the highest interaction affinity with DDT. Hence, this particular GST (D6) is likely to get elevated on exposure of mosquitoes to DDT. Interpretation & conclusion: It would be, therefore, possible to design a specific molecular assay to determine the expression level of such high affinity transcript(s) and to use for resistance diagnosis reliably in the vector surveillance programme.

Background & objectives: In the well-known zoonotic cutaneous leishmaniasis (ZCL) focus in Turkmen Sahara, border of Iran and Turkmenistan, ZCL has increased among humans in the past five years. The present study was undertaken to incriminate vectors of ZCL in the region, and to find molecular variation in Leishmania parasites. Methods: The sandflies were sampled using CDC light-traps and sticky papers. All the sandflies were identified using morphological characters of the head and abdominal terminalia. DNA was extracted from the dissected thorax and attached anterior abdomen of individual female sandfly. Leishmania detection and identification of sandflies were performed using PCR, digestion of BsuRI restriction enzyme and sequencing of ITS-rDNA gene and also by semi-nested PCR to amplify minicircle kinetoplast (k) DNA of Leishmania. Results: Leishmania infections were detected in 26 out of 206 female sandflies. Of the infected sandflies, 18 were Phlebotomus papatasi while eight were P. caucasicus/P. mongolensis. Two infections of L. turnica were detected, one in P. papatasi and other in P. caucasicus/P. mongolensis and the rest of the sandflies were found infected with L. major. Conclusion: Our finding showed that L. major had low diversity with only one common haplotype (GenBank Access No. EF413075). The novel haplotypes were discovered in L. major (GenBank Access No. KF152937) and in L. turanica (GenBank Access No. EF413079) in low frequency. These Leishmania parasites are circulating to maintain infections in the P. papatasi and P. caucasicus/P. mongolensis in Turkmen Sahara.

Background & objectives: Meccus pallidipennis is one of the most epidemiologically important vectors of Trypanosoma cruzi to reservoir hosts in nine states of Mexico. Triatomines occurring in distinct locations normally adapt to local conditions. The aim of this study was to examine the biological attributes of three populations of M. pallidipennis from areas with different environmental characteristics as a factor influencing the triatomine capacity for T. cruzi transmission. Methods: The values of biological parameters related to the life cycle, the number of blood meals to molt to next instar, fecundity and percentage of females after a biological cycle of three populations of M. pallidipennis were evaluated. A cohort of each of the three studied populations from different geographical areas of Mexico was maintained under similar laboratory conditions and then compared with each other. Results: The life cycle was less than six months in all the studied cohorts, with differences among them. The number of blood meals to molt was lower for the cohort from Izϊcar de Matamoros. Laid eggs per day per female was lower for the cohort from Luvianos. In contrast, no important differences were recorded on the percentage of mortality, egg eclosion rate or percentages of obtained females. Interpretation & conclusion: It was found that an important level of heterogeneity exist between the three studied populations of M. pallidipennis, apparently influenced by the remarkable differences on environmental conditions on the localities where the founders were initially collected, that emphasizes the necessity of studies on local populations of triatomines.

Background & objectives: The district of Thiruvananthapuram reports the maximum number of cases of dengue in the state of Kerala. To determine the larval diversity, density and breeding site preferences of Aedes mosquitoes, during pre-monsoon and monsoon periods in urban and rural areas of Thiruvananthapuram district. Methods: Based on the daily reports of dengue cases, 70 clusters were identified in Thiruvananthapuram district. A cross-sectional larval survey was done in the domestic and peri-domestic areas of 1750 houses, using the WHO standard techniques. The larval indices were calculated, and the larvae were identified by using taxonomic keys. Urban and rural differences and the variations during pre-monsoon and monsoon seasons were also studied. Results: In the surveyed houses, 15% had mosquito breeding, with 88% having Aedes larvae. The house index, container index and the breteau index were 13.08, 13.28 and 16.57%, respectively. About 86% of the clusters were found positive for Aedes albopictus and 11% for Ae. aegypti. Aedes albopictus was distributed almost equally in rural and urban clusters, whereas the distribution of Ae. aegypti was significantly higher in urban areas (p = 0.03). The most common water holding containers found (outdoor) were of plastic, followed by coconut shells. The breeding preference ratio was highest for tyres. Significantly lesser positivity was found for containers during monsoon period when compared to pre-monsoon period. Conclusion: The geographical distribution of Ae. albopictus is significantly high in peri-domestic areas and, therefore, its epidemiological role in the widespread disease occurrence needs to be studied. The discarded tyres being the most preferred breeding sites, where IEC activities will help in source reduction.

Background & objectives: Malaria and G6PD deficiency-related haemolyses are known causes of hospital admissions in Nigeria and pose great danger to child survival but data on interactions of these two pathologies are scarce. This study was carried out to determine the association between features of Plasmodium falciparum infection and G6PD status. Methods: G6PD and haemoglobin were typed by fluorescent spot test and electrophoresis respectively, in 1120 children with microscopically-proven falciparum malaria. Clinical features of malaria were compared between G6PD normal and deficient children. Results: There were 558 males and 562 females with median age of 35 months (range, 6 months-12 yr). In males, prevalence of G6PD-deficiency in patients with uncomplicated malaria (UM), severe malarial anaemia (SMA) and cerebral malaria (CM) was 23.4, 7 and 16.7%, respectively compared with 11.1, 7.3 and 4.4%, respectively among females. In both males and females, convulsion and rectal temperature above 38°C were less likely presentations among G6PD-deficient compared with G6PD-normal children (p <0.05). The proportions of children with pallor, convulsion and impaired consciousness were significantly lower among G6PD-deficient than normal males (p <0.05) but these features were not different between deficient and normal females (p >0.05). Interpretation & conclusion: Convulsions, pallor and elevated temperature were more frequent features of malaria in G6PD normal than deficient children. G6PD-deficient male children are protected against impaired consciousness. These differences may offer useful hints in malaria treatment and researches in endemic regions.

Background & objectives: Acute renal failure (ARF) is a known manifestation of severe Plasmodium falciparum (Pf) malaria but recently it has also been observed with P. vivax (Pv) monoinfection. A clinical observational study has been conducted to evaluate the clinical and histopathological profile of ARF in malaria. Methods: This study was conducted on 288 consecutive cases of malaria with monoinfection (Pf 191 and Pv 97) diagnosed by peripheral blood film examination and rapid card test. ARF was diagnosed as per WHO criterion (serum creatinine >3 mg%). The data were analysed by Standard t-test using ANOVA software. Results: ARF was seen in 52 cases of Pf and 14 cases of Pv malaria. Mean age was 32.58 yr (ranging 15-65; Pf 33.37 and Pv 29.14) and male to female ratio was 2:1 (Pf 3:1 and Pv 1:1). Most of the cases developed ARF within 10 days of onset of the disease. Associated severe manifestations were jaundice (53 cases: Pf 44 and Pv 9), cerebral malaria (28 cases: Pf 25 and Pv 3), severe anemia (18 cases: Pf 17 and Pv 1), hypotension (16 cases: Pf 11 and Pv 5), bleeding manifestations (16 cases: Pf 14 and Pv 2), multiorgan failure (12 cases: Pf 9 and Pv 3) and ARDS (6 cases: Pf 5 and Pv 1). Kidney biopsy (16 Pf and 2 Pv) showed acute tubular necrosis (5 Pf and 1 Pv), mesangioproliferative glomerulonephritis (2 Pf) or both (9 Pf and 1 Pv). Haemodialysis was done in 7 (Pf 4 and Pv 3) cases, out of which four survived. Most of the cases (48.49%) recovered within two weeks (range 3-20 days). Total mortality was 27.27% (Pf 28.85% and Pv 21.43%). Interpretation & conclusion: ARF can also be caused by vivax monoinfection with similar clinical and histopathological features although outcome is less severe as compared to falciparum monoinfection.

Background & objectives: Japanese encephalitis (JE) is a major cause of child mortality and disability in the state of Uttar Pradesh. The disease is vaccine preventable since 1941. Yet no major vaccination was available for public health intervention. After a massive breakout in 2005, the government launched vaccination programme in 11 most endemic districts and is planning to incorporate the vaccine in routine immunization with DPT (Diptheria, pertussis and tatanus) booster dose. The paper aims to estimate discounted net benefits and internal rate of return (IRR) to evaluate the economic feasibility for elimination of JE by utilizing available secondary information. Methods: Cross-sectional data were collected from different sources to estimate societal costs and benefits from JE interventions with a 5 yr project period. Total costs are estimated based on the unit cost of inputs used for interventions. The benefits are derived from resources saved due to the reduction of JE incidence. Net benefits and IRRs are estimated based on standard procedures used in the field of economics. Results: A total discounted net benefit of JE vaccination is Rs 598.52 million with 291% IRR. The result suggests that for every rupee invested in vaccination at present will yield Rs 11 benifit per person over five years. The regional benefits from the interventions will be greater than the sum of benefits gained by the individual country due to its nature of public goods. Conclusion: Vaccination against JE is a good investment opportunity despite all operational issues associated with it.