The burden of dengue and force of infection among children in Kerala, India; seroprevalence estimates from Government of Kerala-WHO Dengue study

Background

Dengue shows high geographic heterogeneity within and across endemic countries. In the context of increasing burden and predicted outbreaks due to climate change, understanding the heterogeneity will enable us to develop region specific targeted interventions, including vaccination. World Health Organisation (WHO) suggests standard methodologies to study the burden and heterogeneity at national and subnational levels. Regional studies with robust and standard methodology to capture heterogeneity are scarce. We estimated the seroprevalence of dengue in children aged 9-12 years and the force of infection in Kerala, India, from where Zika cases also have been reported recently.

Methods

We conducted a school-based cross-sectional survey in 38 clusters; selected by stratified random sampling, representing rural, urban, high burden and low-burden administrative units. Validation of Indirect IgG ELISA was done by Plaque Reduction Neutralization Test (PRNT90) using the local isolates of all four serotypes. Force of infection (FOI) was estimated using the WHO-FOI calculator. We conducted a follow-up survey among a subsample of seronegative children, to estimate the rate of sero-conversion.

Results

Among 5236 children tested, 1521 were positive for anti-dengue IgG antibody. The overall seroprevalence in the state was 29% (95% CI 24.1-33.9). The validity corrected seroprevalence was 30.9% in the overall sample, 46.9% in Thiruvananthapuram, 26.9% in Kozhikkode and 24.9% in Kollam. Age-specific seroprevalence increased with age; 25.7% at 9 years, 29.5% at 10 years, 30.9% at 11 years and 33.9% at 12 years. Seroprevalence varied widely across clusters (16.1%-71.4%). The estimated force of infection was 3.3/100 person-years and the seroconversion rate was 4.8/100 person-years. 90% of children who tested positive were not aware of dengue infection. All the four serotypes were identified in PRNT and 40% of positive samples had antibodies against multiple serotypes.

Interpretation

The study validates the WHO methodology for dengue serosurveys and confirms its feasibility in a community setting. The overall seroprevalence in the 9-12 year age group is low to moderate in Kerala; there are regional variations; high burden and low burden clusters co-exist in the same districts. The actual burden of dengue exceeds the reported numbers. Heterogeneity in prevalence, the high proportion of inapparent dengue and the hyperendemic situation suggest the need for region-specific and targeted interventions, including vaccination.

Funding

World Health Organization.

Effectiveness of a Non-pharmacological Intervention to Control Diabetes Mellitus in a Primary Care Setting in Kerala: A Cluster-Randomized Controlled Trial

Background: Despite being the first Indian state with a dedicated Non-Communicable Disease (NCD) program, glycemic control among a large proportion of patients is low in Kerala. This study tries to find evidence for a standardized non-pharmacological strategy delivered through Junior Public Health Nurses (JPHNs) in achieving and maintaining glycemic control among diabetic patients registered with NCD clinics of primary health care settings. Design: A cluster randomized controlled trial was conducted among adult patients with Diabetes Mellitus attending NCD clinics of primary care settings of South Kerala, India. JPHNs of the intervention group received additional module-based training while standard management continued in the control group. Sequence generation was done by random permuted blocks method and a cluster of 12 patients was selected from each of the 11 settings by computer-generated random numbers. Patients were followed up for 6 months with monthly monitoring of Fasting Blood Sugar (FBS), Post-Prandial Blood Sugar (PPBS), blood pressure, Body Mass Index (BMI), and health-related behaviors. Knowledge and skills/practice of JPHNs were also evaluated. Analysis of Covariance was done to study the final outcome adjusting for the baseline values and a model for glycemic control was predicted using multilevel modeling. Results: We analyzed 72 participants in the intervention group and 60 participants in the control group according to the intention-to-treat principle. The intervention was associated with a significant reduction in FBS (p < 0.001) and PPBS (p < 0.001) adjusting for the baseline values. The achievement of glycemic control was 1.5 (95% CI: 1.05-2.3) times better with intervention and they showed a better trend of maintenance of glycemic control (FBS, p = 0.003 and PPBS, p = 0.039). Adjusting for clustering and the baseline values, the intervention showed a significant effect on FBS (B = -3.1, SE = 0.57; p < 0.001) and PPBS (B = -0.81, SE = 0.3; p < 0.001) with time. Drug adherence score (p < 0.001), hours of physical activity (p < 0.001), BMI (p = 0.002), fruit intake (p = 0.004), and green leafy vegetable intake (p = 0.01) were the major predictors of FBS control. The practice/skills score of the JPHNs significantly improved with intervention (p < 0.001) adjusting for baseline values. Conclusion: A well-designed health worker intervention package incorporated into the existing health system can translate into attitude change and skill development in the health workers which can reflect in the improvement of glycemic control among the patients. Trial registration: [URL: http://www.ctri.nic.in], identifier [CTRI/2017/11/010622].

Strategies and challenges in Kerala's response to the initial phase of COVID-19 pandemic: a qualitative descriptive study

OBJECTIVE

To understand the structures and strategies that helped Kerala in fighting the COVID-19 pandemic, the challenges faced by the state and how it was tackled.

DESIGN

Qualitative descriptive study using focus group discussions and in-depth interviews.

SETTING

State of Kerala, India.

PARTICIPANTS

29 participants: four focus group discussions and eight in-depth interviews. Participants were chosen purposively based on their involvement in decision-making and implementation of COVID-19 control activities, from the department of health and family welfare, police, revenue, local self-government and community-based organisations. Districts, panchayats (local bodies) and primary health centres (PHCs) were selected based on epidemiological features of the area like the intensity of disease transmission and preventive/containment activities carried out in that particular area to capture the wide range of activities undertaken in the state.

RESULTS

The study identified five major themes that can inform best practices viz social capital, robust public health system, participation and volunteerism, health system preparedness, and challenges. This study was a real-time exploration of the intricacies of COVID-19 management in a low/middle-income country and the model can serve as an example for other states and nations to emulate or adjust accordingly.

CONCLUSION

The study shows the impact of synergy of these themes towards more effective solutions; however, further research is much needed in examining the relationship between these factors and their relevance in policy decisions.