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Objectives: Indoor residual spraying (IRS) with insecticides is the main vector control intervention for the elimination of visceral leishmaniasis in India. After a change in IRS policy in 2015 due to widespread resistance of Phlebotomus argentipes to DDT, IRS with DDT was replaced with alpha‐cypermethrin IRS in 2016. The objective of the present study was to evaluate the susceptibility of P. argentipes to DDT and its alternatives, namely malathion and pirimiphos‐methyl (organophosphates); alpha‐cypermethrin, deltamethrin, lambda‐cyhalothrin and permethrin (pyrethroids), and bendiocarb and propoxur (carbamates), in support of visceral leishmaniasis elimination in India. Methods: Phlebotomus argentipes sandflies were collected from the visceral‐leishmaniasis endemic states of Bihar, Jharkhand and West Bengal. In the WHO tube tests, the phenotypic susceptibility of F1, 2‐day old, non‐blood fed females were determined against filter papers impregnated with DDT 4%, malathion 5%, pirimiphos‐methyl 0.25%, alpha‐cypermethrin 0.05%, deltamethrin 0.05%, lambda‐cyhalothrin 0.05%, permethrin 0.75%, bendiocarb 0.1% and propoxur 0.1%, which were sourced from Universiti Sains Malaysia. The knockdown of sandflies after 1‐h exposure and mortality at 24 h after the 1‐h exposure period were scored. Results: Mean mortality of P. argentipes 24 h after exposure in tube tests was 22.6% for DDT and ≥ 98% for other insecticide‐impregnated papers tested. Conclusion: Phlebotomus argentipes continues to be highly resistant to DDT with no reversal of resistance after DDT's withdrawal from IRS. P. argentipes was fully susceptible to pyrethroid, organophosphate and carbamate insecticides tested. Regular monitoring is warranted for insecticide resistance management in sandfly vectors. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate the entomological efficacy and the residual activity of indoor residual spraying with Fludora® Fusion 562.5 WP‐SB, a combination formulation containing clothianidin, a neonicotinoid and deltamethrin, a pyrethroid, against the main rural malaria vector, Anopheles culicifacies s.l., in India in a small‐scale trial. Methods: In three study villages, suitable households were randomly allocated to five treatments: Fludora® Fusion 562.5 WP‐SB (target dose 225 mg active ingredient AI/m2); clothianidin 70 WG (target dose 200 mg AI/m2); K‐Othrine 250 WG (deltamethrin, target dose 25 mg AI/m2); Ficam VC 80 WP‐SB (bendiocarb, target dose 400 mg AI/m2) and unsprayed control. Insecticides were sprayed by hand compression sprayers with control flow valves and 8002E nozzles. Post‐spray cone bioassays were done on insecticide‐treated walls using a colonised, deltamethrin‐resistant strain of An. culicifacies. Mosquitoes were collected from treated rooms by different methods. The insecticide content on filter papers collected from the sprayed walls was determined by chemical assay to assess the spray quality. Results: The ratios of applied to target doses of insecticides were within 0.84 to 1.4, showing a good spray quality. The cone bioassays revealed residual action lasting 7 months for all insecticides without significant differences in mortality between different surfaces treated nor between the four treatment arms (P > 0.05). Considering all entomological parameters such as indoor resting density, excito‐repellency, blood‐feeding inhibition and delayed mortality, the overall efficacy of Fludora® Fusion WG‐SB was equal or better compared with other insecticides. Conclusions: Fludora® Fusion showed overall equal or better efficacy than deltamethrin and bendiocarb alone against a pyrethroid‐resistant malaria vector population and can be considered as an alternative product for management of pyrethroid resistance in malaria vectors. [ABSTRACT FROM AUTHOR]

Objective: There is an urgent need to test and incorporate new molecules with promising efficacy and novel mode of action to control insecticide-resistant mosquito vectors for disease control. We tested a new compound, clothianidin (SumiShield 50 WG), for its efficacy as an indoor residual spray (IRS) for the control of pyrethroid-resistant Anopheles culicifacies (Diptera: Culicidae) in comparison with pirimiphos methyl (Actellic CS) as a positive control.Methods: Ten villages were selected, five each for IRS with clothianidin (300 mg AI/m2 ) and pirimiphos methyl (1000 mg AI/m2 ) in Almatti Dam catchment area in Karnataka state, India. Entomological parameters were monitored in these sprayed villages using standard methods. Assessment of quality of spray was performed by analysing the insecticide content in the filter paper samples collected from sprayed houses. Perceptions of spray men and inhabitants were recorded post-spray on safety of these molecules.Results: The mean applied to target ratio of content was 1.7 (n = 29) for clothianidin and 1.8 (n = 50) for pirimiphos methyl on filter paper samples analysed. Residual activity (≥80% mortality in exposed mosquitoes) after 24 h post-exposure of SumiShield WG was 5 months and increased to 6 months when the holding period was extended to 120 h and that of Actellic CS was 3 months at 24-h holding period and extended to 4 months at 120-h extended holding period. The mean densities of An. culicifacies in both arms fell drastically post-spray. In light trap collections, density of mosquitoes collected indoors was lower than outdoors in both arms indicating effectiveness of IRS. SumiShield WG was more efficacious in reducing the per-structure density than Actellic CS. The proportion of nulliparous mosquitoes was higher than that of parous mosquitoes during post-spray collections in both arms. The majority of adverse events reported were transitory and subsided without medication.Conclusion: Indoor residual spraying with SumiShield WG was found effective, operationally feasible and safe, and it is effective for up to 6 months. [ABSTRACT FROM AUTHOR]

This paper reports the coverage, compliance and other operational issues of mass drug administration (MDA) of diethylcarbamazine and albendazole under a programme to eliminate lymphatic filariasis (LF) in Orissa state of India. Both quantitative and qualitative methods were used to collect data from 90 villages and nine urban areas of four districts of Orissa, India. In Orissa, 67% of people older than 2 years had received the drugs during MDA and 42% had consumed them. About 25% of people had not taken the tablets although they received them. Urban areas recorded lower rates than rural areas. The paper discusses some policy/health system-, community- and drug-related issues that influenced coverage and compliance of MDA. It is essential to improve compliance in future rounds of MDA to achieve targets of control and eventual elimination of LF in a reasonable time frame. [ABSTRACT FROM AUTHOR]

The Revised National Tuberculosis Control Programme (RNTCP), based on the World Health Organization's DOTS strategy,* was introduced in India in the mid-1990s. This paper reports the findings from operational research studies in two pilot sites in New Delhi from 1996 to 1998. A variety of operational research methods were used, including semi-structured interviews, focus group discussions, non-participant observations and collection of data from the tuberculosis registers. The cure rates for the clinics were 71 and 75% with a default rate of 6 and 11%, respectively. An important finding was that health workers screened patients to determine their ability to conform to the direct observation of treatment element of the RNTCP. If the health worker was confident that the patient would comply and/or be easy to trace in the community in the event of 'default', they were provided with short-course treatment under the RNTCP. Other patients, largely those who were in absolute poverty, socially marginalized, itinerant labourers, poorly integrated in the city, were put on standard tuberculosis (TB) treatment as for the previous National TB Programme. The programme was evidently excluding the most vulnerable from the best available care. These findings demonstrate the potential dangers of target-driven programmes where there is an absence of support to both frontline health workers and patients. The paper also highlights the importance of operations research in helping to identify problems within TB programmes. [ABSTRACT FROM AUTHOR]

Objective Visceral Leishmaniasis (VL) is highly prevalent in Bihar, India. India and its neighbours aim at eliminating VL, but several knowledge gaps in the epidemiology of VL may hamper that effort. The prevalence of asymptomatic infections with Leishmania donovani and their role in transmission dynamics are not well understood. We report data from a sero-survey in Bihar. Methods Demographic and immunological surveys were carried out in July and November 2006, respectively in 16 highly VL endemic foci in Muzaffarpur district in Bihar. Household and individual information was gathered and capillary blood samples were collected on filter papers. Direct agglutination test (DAT) was used to determine infected individuals (cut-off titre 1:1600). DAT results were tabulated against individual and household variables. A multivariate generalized estimating equation (GEE) model was used to study the prevalence of serologically positive individuals taking into account the clustering at household and cluster levels. Results Of study subjects 18% were DAT positive, and this proportion increased with age. Women had a significantly lower prevalence than men >14 years old. Owning domestic animals (cows, buffaloes or goats) was associated with a higher risk of being DAT positive [OR 1.16 (95% CI 1.01–1.32)], but socio-economic status was not. Conclusions Prevalence of leishmanial antibodies was high in these communities, but variable. Demographic factors (i.e. marriage) may explain the lower DAT positivity in women >14 years of age. Within these homogeneously poor communities, socio-economic status was not linked to L. donovani infection risk at the individual level, but ownership of domestic animals was. [ABSTRACT FROM AUTHOR]

In this phase III trial for diagnostics for visceral leishmaniasis (VL) in India, we compared parasitological diagnosis with several serological tests: direct agglutination test (freeze dried; DAT-FD), rK-39 strip test, rK-26 strip test and a latex agglutination test for antigen detection in urine (KAtex) in 452 subjects from the endemic regions of Bihar, India. The subjects were segregated into four categories: 230 confirmed patients, 52 probable cases, 70 non-cases and 100 healthy endemic controls. The first two groups were used for estimating sensitivity, the latter two for specificity. Sensitivity of DAT-FD was 98.9%, rK-39: 98.9%, KAtex: 67.0% and rK-26: 21.3%. Sensitivity of DAT-FD on blood taken on filter paper (DAT-FDF) was 99.3%, which was comparable with that using serum. Specificity of serological tests was comparable and high (DAT-FD and DAT-FDF: 94%, rK-39 strip test: 97%, KAtex: 99% and rK-26 strip test: 100%). The classical ‘gold standard’ parasitological demonstration in splenic smear performed poorly as it missed 18.4% of cases that benefited from VL treatment. Reproducibility of the serological tests between field and central laboratories was excellent ( κ = 1.0, 0.99, 0.96 and 0.94 respectively for microscopy, DAT-FD, rK-39 strip test and rK-26 strip test). A high degree of agreement was observed between DAT-FD and rK-39 strip test ( κ = 0.986). Although DAT-FD and rK-39 strip test were highly sensitive with excellent specificity, the ease of use of the latter makes it most suitable for the diagnosis of VL in the field conditions. [ABSTRACT FROM AUTHOR]

The Revised National Tuberculosis Control Programme (RNTCP), which incorporated the WHO DOTS strategy was introduced in India in the mid-1990s. An operational research project was conducted between 1996 and 1998 to assess the needs and perspectives of patients and providers in two chest clinics in Delhi, Moti Nagar and Nehru Nagar, during the introduction of the new strategy. This paper reports on the findings of the project, concentrating on information collected from 40 in-depth interviews with patient defaulters and from non-participant observations in clinics and directly observed treatment centres. In Moti Nagar chest clinic, 117 of 1786 (6.5%) patients and 195 of 1890 (10%) patients in Nehru Nagar left care before their treatment was complete. It was argued that the reasons for default stem from a poor correlation between patient and programme needs and priorities, and from particular characteristics of the disease and its treatment. Patient needs that were not met by the health system included convenient clinic timings, arrangements for the provision for treatment in the event of a family emergency and provision for complicated cases like alcoholics. The problems facing the provider were poor interpersonal communication with the health staff, lack of attention and support at the clinic, difficulty for patients to re-enter the system if they missed treatment and, in certain areas, long distances to the clinic. Problems related to diseases were inability of the staff to deal with drug side-effects, and patients' conception of equating well-being with cure. Simple, practical measures could improve the provision of tuberculosis (TB) treatment: more flexible hours, allowances for poor patients to reach the clinics and training health care staff for respectful communication and monitoring drug side-effects. The findings indicate a need to rethink the label of 'defaulter' often given to the patients. The important areas for future operational research is also highlighted. [ABSTRACT FROM AUTHOR]

India has the world's highest number of HIV/AIDS infections for any country outside Africa. Eighty-five per cent of HIV transmission in India occurs through heterosexual contact. One billion population, a large number of female sex workers, high prevalence of sexually transmitted infection (STIs) and low condom use make a potent combination for explosive growth of the epidemic. Taking available estimates of the number of female sex workers (FSWs), their work patterns, prevalence of HIV and STIs and condom use among them in 1999 as the base, and adopting reasonable infectivity rates, this paper attempts to present a model to estimate the spread of HIV infection in commercial sex networks until 2005. HIV infections in commercial sex networks are estimated to increase from the 1999 level of approximately 2.49 million to about 3.93 million by 2005 in a favourable scenario, and to 6.87 million in a worse scenario. Spread of HIV is influenced in the short term by condom use and prevalence of STIs, and these are the only factors that can be manipulated to limit the spread of the infection. [ABSTRACT FROM AUTHOR]

This paper reports on DEC distribution and compliance with treatment in a large-scale annual single-dose mass treatment programme to eliminate lymphatic filariasis in the south Indian state of Tamil Nadu. 76.9% of households (82.5% in rural areas and 58.0% in urban areas) were aware of drug distribution for control of filariasis. DEC was given to 70% (= distribution rate) (range 0-92%) of the population and 53.5% (range 12-89%) complied with treatment. The distribution rate was more than 75% in 74% of the villages and compliance was in the range of 51-75% in 76% of the villages. About 5% of the treated population reported side-effects. Distribution and compliance were higher in rural than urban areas and similar between males and females. Qualitative data showed that some socio-economic factors, logistic and drug-related problems and people's poor knowledge and perceived benefits of treatment played a role in a proportion of the population not receiving or taking the drug. The Tamil Nadu programme showed that large-scale repeated annual DEC mass treatment is feasible and that existing health services are capable of delivering the drug to all communities. While even poor to moderate compliance rates can reduce the vector transmission of infection to some extent, improved drug distribution and compliance with treatment are necessary to consolidate the gains of earlier rounds of treatment and achieve the goal of filariasis elimination within a reasonable time frame. [ABSTRACT FROM AUTHOR]

Rapid assessment procedures informed by anthropology are increasingly commonly being utilised in the formulation of a range of international disease control and prevention strategies. Refinement of these rapid procedures has narrowly focused on their methods, in contrast with the broader potential scope of context-based anthropological contributions. The control of HIV and other sexually transmitted diseases (STDs) in India is used to illustrate the potential role of anthropologically informed insights and investigations in the development of effective interventions, with particular reference to the examples of syndromic management, symptom presentation and treatment provision. The paper argues for anthropological epidemiological and clinical studies to be properly integrated in order to fulfil their substantial potential for interdisciplinary illumination. [ABSTRACT FROM AUTHOR]