Assessment of larval and pupal indices of dengue mosquito vectors in a North-Eastern state of Tripura, India.

BACKGROUND OBJECTIVES: Dengue is a major vector-borne disease having public health importance. It is caused by Dengue Virus (DENV) and is transmitted by mosquitoes of Aedes species. With the unavailability of a vaccine, vector control remains the only preventive measure for dengue. Studies have already been conducted to establish the presence of dengue vectors in the north-eastern states of India. However, limited studies have been conducted in Tripura state. In the present study we aimed to identify the preferred breeding habitats of dengue vectors in the state. METHODS: Clinical case data of dengue since the last five years was studied and the areas with the highest case numbers were identified. Entomological investigation was carried out in areas reporting the highest number of cases. Larvae were collected from the breeding habitats using standard protocol followed by morphological and molecular identification. Further, House index (HI), Container index (CI) and Pupal index (PI) were determined. The positive pools were then processed for incrimination for the presence of dengue virus. Calculation of entomological indices was done. RESULTS: Of the total 815 containers searched, 36.80% containers were positive for mosquito larvae. Among the immature mosquito collection, 836 adults emerged and were identified as Aedes albopictus using standard taxonomic keys followed by molecular methods. HI, CI and PI, varied from 15.38% to 100%, 21% to 31.04 %, and 2.93% to 110.53% respectively. However, none of the pools was positive for dengue virus. INTERPRETATION CONCLUSION: The present study identified Ae. albopictus as a potential vector of dengue in Tripura. The study gave important insights on the preferred larval habitats and provides information on the indication of displacement of Ae. albopictus from rural to urban and semi-urban areas. However, longitudinal studies for longer time frame are necessary for any conclusive remarks.

Triple artemisinin-based combination therapies versus artemisinin-based combination therapies for uncomplicated Plasmodium falciparum malaria: a multicentre, open-label, randomised clinical trial.

BACKGROUND: Artemisinin and partner-drug resistance in Plasmodium falciparum are major threats to malaria control and elimination. Triple artemisinin-based combination therapies (TACTs), which combine existing co-formulated ACTs with a second partner drug that is slowly eliminated, might provide effective treatment and delay emergence of antimalarial drug resistance. METHODS: In this multicentre, open-label, randomised trial, we recruited patients with uncomplicated P falciparum malaria at 18 hospitals and health clinics in eight countries. Eligible patients were aged 2-65 years, with acute, uncomplicated P falciparum malaria alone or mixed with non-falciparum species, and a temperature of 37·5°C or higher, or a history of fever in the past 24 h. Patients were randomly assigned (1:1) to one of two treatments using block randomisation, depending on their location: in Thailand, Cambodia, Vietnam, and Myanmar patients were assigned to either dihydroartemisinin-piperaquine or dihydroartemisinin-piperaquine plus mefloquine; at three sites in Cambodia they were assigned to either artesunate-mefloquine or dihydroartemisinin-piperaquine plus mefloquine; and in Laos, Myanmar, Bangladesh, India, and the Democratic Republic of the Congo they were assigned to either artemether-lumefantrine or artemether-lumefantrine plus amodiaquine. All drugs were administered orally and doses varied by drug combination and site. Patients were followed-up weekly for 42 days. The primary endpoint was efficacy, defined by 42-day PCR-corrected adequate clinical and parasitological response. Primary analysis was by intention to treat. A detailed assessment of safety and tolerability of the study drugs was done in all patients randomly assigned to treatment. This study is registered at ClinicalTrials.gov, NCT02453308, and is complete. FINDINGS: Between Aug 7, 2015, and Feb 8, 2018, 1100 patients were given either dihydroartemisinin-piperaquine (183 [17%]), dihydroartemisinin-piperaquine plus mefloquine (269 [24%]), artesunate-mefloquine (73 [7%]), artemether-lumefantrine (289 [26%]), or artemether-lumefantrine plus amodiaquine (286 [26%]). The median age was 23 years (IQR 13 to 34) and 854 (78%) of 1100 patients were male. In Cambodia, Thailand, and Vietnam the 42-day PCR-corrected efficacy after dihydroartemisinin-piperaquine plus mefloquine was 98% (149 of 152; 95% CI 94 to 100) and after dihydroartemisinin-piperaquine was 48% (67 of 141; 95% CI 39 to 56; risk difference 51%, 95% CI 42 to 59; p<0·0001). Efficacy of dihydroartemisinin-piperaquine plus mefloquine in the three sites in Myanmar was 91% (42 of 46; 95% CI 79 to 98) versus 100% (42 of 42; 95% CI 92 to 100) after dihydroartemisinin-piperaquine (risk difference 9%, 95% CI 1 to 17; p=0·12). The 42-day PCR corrected efficacy of dihydroartemisinin-piperaquine plus mefloquine (96% [68 of 71; 95% CI 88 to 99]) was non-inferior to that of artesunate-mefloquine (95% [69 of 73; 95% CI 87 to 99]) in three sites in Cambodia (risk difference 1%; 95% CI -6 to 8; p=1·00). The overall 42-day PCR-corrected efficacy of artemether-lumefantrine plus amodiaquine (98% [281 of 286; 95% CI 97 to 99]) was similar to that of artemether-lumefantrine (97% [279 of 289; 95% CI 94 to 98]; risk difference 2%, 95% CI -1 to 4; p=0·30). Both TACTs were well tolerated, although early vomiting (within 1 h) was more frequent after dihydroartemisinin-piperaquine plus mefloquine (30 [3·8%] of 794) than after dihydroartemisinin-piperaquine (eight [1·5%] of 543; p=0·012). Vomiting after artemether-lumefantrine plus amodiaquine (22 [1·3%] of 1703) and artemether-lumefantrine (11 [0·6%] of 1721) was infrequent. Adding amodiaquine to artemether-lumefantrine extended the electrocardiogram corrected QT interval (mean increase at 52 h compared with baseline of 8·8 ms [SD 18·6] vs 0·9 ms [16·1]; p<0·01) but adding mefloquine to dihydroartemisinin-piperaquine did not (mean increase of 22·1 ms [SD 19·2] for dihydroartemisinin-piperaquine vs 20·8 ms [SD 17·8] for dihydroartemisinin-piperaquine plus mefloquine; p=0·50). INTERPRETATION: Dihydroartemisinin-piperaquine plus mefloquine and artemether-lumefantrine plus amodiaquine TACTs are efficacious, well tolerated, and safe treatments of uncomplicated P falciparum malaria, including in areas with artemisinin and ACT partner-drug resistance. FUNDING: UK Department for International Development, Wellcome Trust, Bill & Melinda Gates Foundation, UK Medical Research Council, and US National Institutes of Health.

Determinants of child sex ratio in West and South Districts of Tripura, India.

BACKGROUND: Indian census 2011 has detected declined child sex ratio in the West and South districts of Tripura State. OBJECTIVES: To find out the sex ratio at birth and to identify the factors affecting child sex ratio in west and south districts of Tripura. METHODS: This community-based cross-sectional study combined with a qualitative component was conducted among 3438 couples chosen by multistage sampling. Quantitative data were collected by a structured interview schedule. Data were analyzed by computer using SPSS version 15.0. Chi-square test was applied for testing the significance of study findings and P < 0.05 was considered statistically significant. Qualitative data were collected by Focus Group Discussions and analyzed by qualitative free listing and pile sorting considering Smith's S value. RESULTS: Sex ratio at birth in West and South Tripura districts during 2013 was found to be 972 and 829 respectively. Son preference was higher among couples irrespective of their literacy, residence, occupation, family type and religion except Christianity. Expenditure at marriage, lesser contribution to parent's family and fears of adverse situations at in law's house after marriage etc. were causes for lesser daughter preference. Very few pregnant women underwent ultrasonography for sex determination of fetus. Girls had differential or delayed medical care and higher death rate. The desire for children was found to be limited after male births. CONCLUSIONS: Low daughter preference was mostly due to economic reasons and prolonged contraception following male birth. Literacy, occupation and residence of study subjects did not modify prevalent higher male preference.

Anti-SARS-CoV-2 antibody kinetics up to 6 months of follow-up: Result from a nation-wide population-based, age stratified sero-epidemiological prospective cohort study in India.

Repeated serological testing tells about the change in the overall infection in a community. This study aimed to evaluate changes in antibody prevalence and kinetics in a closed cohort over six months in different sub-populations in India. The study included 10,000 participants from rural and urban areas in five states and measured SARS-CoV-2 antibodies in serum in three follow-up rounds. The overall seroprevalence increased from 73.9% in round one to 90.7% in round two and 92.9% in round three. Among seropositive rural participants in round one, 98.2% remained positive in round two, and this percentage remained stable in urban and tribal areas in round three. The results showed high antibody prevalence that increased over time and was not different based on area, age group, or sex. Vaccinated individuals had higher antibody prevalence, and nearly all participants had antibody positivity for up to six months.

Antibody Responses of SARS-CoV-2 Vaccines amongst Health Care Workers in a Tertiary Care Hospital in Tripura, India: A Cross-Sectional Study.

Background: Vaccines against COVID-19 plays an important role in limiting the spread of SARS-CoV-2 infections and also in curbing mortality and morbidity due to COVID-19. Objective: To estimate the anti-spike antibody response after receiving the second dose of SARS-CoV-2 vaccines amongst health care workers of a tertiary care hospital in Tripura, India. Materials and Method: A cross- sectional study was conducted from 1 July to 20 August 2021 at Agartala Government Medical College and GBP Hospital, Agartala among 561 health care workers who had received first and second doses of SARS-CoV-2 vaccines and had completed 14 days after receiving the second dose. Results: The present study showed that health care workers who had received both doses of COVID-19 vaccine had 99.5% seropositivity to anti-spike antibody. The median SARS-CoV-2 anti-spike antibody titter was 250 with an IQR (211.55-250). Seropositivity rate was higher among Covishield recipients (99.8% [550/551]) as compared to Covaxin recipients (80% [8/10]) and it was found to be statistically significant (P = 0.000). Conclusion: The present study suggests that a good immune response was elicited against spike antigen of SARS-CoV-2 after two complete doses of Covishield (ChAdOx1-nCoV-19) or Covaxin (BBV152).

Serological prevalence of SARS-CoV-2 antibody among children and young age group (between 2 and 17 years) in India: An interim result from a large multicentric population-based seroepidemiological study.

Background: Estimating seroepidemiolgical prevalence of SARS-CoV-2 antibody is an essential public health strategy. There is insufficient evidence of prevalence among those belonging to young age population in India. Objective: To compare the SARS-CoV-2 seropositivity rate between children and adults in selected sites from India. Materials and Methods: This was a multicentric population-based seroepidemiological study conducted in selected urban and rural areas of five sites selected from four states (Delhi, Odisha, Uttar Pradesh, Tripura) of India. Participants aged ≥1 year were included from different clusters of each area. Total serum antibody against SARS-CoV-2 virus was assessed qualitatively by using a standard enzyme-linked immunosorbent assay (ELISA) kit. Results: Data collection period was from 15 March 2021 to 10 June 2021. Total available data was of 4509 participants, of whom 700 were <18 years of age and 3809 were ≥18 years of age. The site-wise number of available data among those aged 2-17 years was 92, 189, 165, 146 and 108 for the sites of Delhi urban, Delhi rural, Bhubaneswar rural, Gorakhpur rural and Agartala rural area, respectively. The seroprevalence was 55.7% in the <18 years age group and 63.5% in the ≥18 years age group. The prevalence among female children was 58% and among male children was 53%. Conclusion: SARS-CoV-2 seropositivity rate among children was high and comparable to that of the adult population. Hence, it is unlikely that any future third wave by prevailing SARS-CoV-2 variant would disproportionately infect children 2 years or older.

Development and On-Field Deployment of a Mobile-Based Application 'MoSQuIT' for Malaria Surveillance in International Border Districts of Northeast India-Challenges and Opportunities.

The conventional paper-based system for malaria surveillance is time-consuming, difficult to track and resource-intensive. Few digital platforms are in use but wide-scale deployment and acceptability remain to be seen. To address this issue, we created a malaria surveillance mobile app that offers real-time data to stakeholders and establishes a centralised data repository. The MoSQuIT app was designed to collect data from the field and was integrated with a web-based platform for data integration and analysis. The MoSQuIT app was deployed on mobile phones of accredited social health activists (ASHA) working in international border villages in the northeast (NE) Indian states of Assam, Tripura and Arunachal Pradesh for 20 months in a phased manner. This paper shares the challenges and opportunities associated with the use of MoSQuIT for malaria surveillance. MoSQuIT employs the same data entry formats as the NVBDCP's malaria surveillance programme. Using this app, a total of 8221 fever cases were recorded, which included 1192 (14.5%) cases of P. falciparum malaria, 280 (3.4%) cases of P. vivax malaria and 52 (0.6%) mixed infection cases. Depending on network availability, GPS coordinates of the fever cases were acquired by the app. The present study demonstrated that mobile-phone-based malaria surveillance facilitates the quick transmission of data from the field to decision makers. Geospatial tagging of cases helped with easy visualisation of the case distribution for the identification of malaria-prone areas and potential outbreaks, especially in hilly and remote regions of Northeast India. However, to achieve the full operational potential of the system, operational challenges have to be overcome.

A comparative study on knowledge and practice against malaria among Accredited Social Health Activists (ASHAs) of low and high endemic regions of Tripura, Northeast India.

INTRODUCTION: This study was conducted to compare and evaluate the knowledge as well as the practice of community health volunteers, Accredited social health activists (ASHAs) in low and high malaria-endemic regions of Tripura, Northeast India. MATERIALS AND METHODS: In this descriptive cross-sectional study, all ASHAs working in the randomly selected two blocks of each low and high malaria-endemic areas were included in the study. While ASHAs with less than 1-year experience were excluded from the study. The ASHAs were interviewed and information was gathered on knowledge and practice against malaria management. Chi-square test was used to identify differences in responses among the ASHAs. RESULTS: Significant differences in knowledge of mixed malarial infection (P < 0.001) and early symptoms of malaria (P = 0.005) were observed when responses of high malaria-endemic ASHAs (HMEA) were compared to low endemic ASHAs (LMEA). With respect to malaria testing skills, 83.16% HMEA affirmed that they could perform Rapid diagnostic (RD) kit tests as opposed to 57.24% LMEA, (P < 0.001). Disturbingly only two HMEA could correctly describe the duration for Pf and Pv treatment. CONCLUSION: The study identifies major lacunae in the balance of knowledge and practices of ASHAs in both study areas of Tripura. Therefore,for a successful projected malaria elimination program, community-level ASHA volunteers need to have accurate malaria knowledge and management approaches irrespective of the endemicity. This study will help to understand the operational constraints and plan educational training for ASHA volunteers in malaria-endemic regions.

A Study to Find Out the Full Immunization Coverage of 12 to 23-month old Children and Areas of Under-Performance using LQAS Technique in a Rural Area of Tripura.

INTRODUCTION: It is very important to analyze the factors which acts as obstacle in achieving 100% immunization among children. Lot Quality Assurance Sampling (LQAS) is one of the effective method to assess such barriers. AIM: To assess the full immunization coverage among 12 to 23-month old children of rural field practice area under Department of Community Medicine, Agartala Government Medical College and identify the factors for failure of full immunization. MATERIALS AND METHODS: A community based cross-sectional study was conducted from November 2013 to October 2014 on children aged 12 to 23 months old of area under Mohanpur Community health centre. Using LQAS technique 330 samples were selected with multi-stage sampling, each sub-centre being one lot and two calculated to be the decision value. Data was collected using pre-designed pre-tested questionnaire during home visit and verifying immunization card and analysed by computer software SPSS version 21.0. RESULTS: The full immunization coverage among 12 to 23 months old children of Mohanpur area was found as 91.67%. Out of all the 22 sub-centres, 36.36% was found under performing as per pre-fixed criteria and the main reasons for failure of full immunization in those areas are unawareness of need of subsequent doses of vaccines and illness of the children. CONCLUSION: LQAS is an effective method to identify areas of under-performance even though overall full immunization coverage is high.

A study of adherence to DOTS regimen among pulmonary tuberculosis patients in West Tripura District.

BACKGROUND: Noncompliance to the DOTS regimen leads to treatment failure, relapse, MDR tuberculosis, XDR tuberculosis etc. requiring more prolonged & expensive therapy. AIM: To assess the adherence rate among pulmonary tuberculosis patients in west Tripura district and to study the factors affecting adherence to DOTS regimen among pulmonary tuberculosis patients. MATERIAL AND METHODS: This community based cross-sectional study was conducted among 220 pulmonary tuberculosis patients registered for treatment with DOTS therapy; under six randomly selected DMC of West Tripura District. RESULTS: The study revealed that the adherence rate among the pulmonary TB patients was 84.50 percent. Male tuberculosis patients had 87.10 percent less chance of being adherent to the DOTS regimen in reference to females, and Cat I patients were 8.96 times (C.I. 2.689-29.857) more adherent to the therapy compared to the retreatment cases. Again, patients whose continuation phase was supervised as per the guidelines of DOTS were 12.07 times more adherent to the therapy. PTB patients who had the knowledge of supervised therapy in DOTS and curability of the disease, were 4.70 times (C.I. 1.39-15.79) and 9.39 times (C.I. 1.03-85.99) more adherent to the therapy, respectively. CONCLUSION: The study showed good adherence to the regimen among pulmonary tuberculosis patients in spite of being a difficult area. It may also help in planning and implementation of tuberculosis control measures by addressing and overcoming the barriers regarding treatment completion.