Seasonal variation and etiologic inferences of childhood pneumonia and diarrhea mortality in India
- St Michael's Hospital, Canada
- King George's Medical University, India
- Postgraduate Institute of Medical Education and Research, India
- Indian Council of Medical Research, India
- Johns Hopkins Bloomberg School of Public Health, United States
- Hospital for Sick Children, Canada
Abstract
Future control of pneumonia and diarrhea mortality in India requires understanding of their etiologies. We combined time series analysis of seasonality, climate-region, and clinical syndromes from 243,000 verbal autopsies in the nationally-representative Million Death Study. Pneumonia mortality at 1 month-14 years was greatest in January (Rate ratio (RR) 1.66, 99%CI 1.51-1.82; versus the April minimum). Higher RRs at 1-11 months suggested respiratory syncytial virus (RSV) etiology. India's humid subtropical region experienced a unique summer pneumonia mortality. Diarrhea mortality peaked in July (RR 1.66, 1.48-1.85) and January (RR 1.37, 1.23-1.48), while deaths with fever and bloody diarrhea (indicating enteroinvasive bacterial etiology) showed little seasonality. Combining mortality at ages 1-59-months in 2015 with prevalence surveys, we estimate 40,600 pneumonia deaths from Streptococcus pneumoniae, 20,700 from RSV, 12,600 from influenza, and 7,200 from Haemophilus influenzae type b and 24,700 diarrheal deaths from rotavirus. Careful mortality studies can elucidate etiologies and inform vaccine introduction.
Data availability
Data from the Million Death Study cannot be redistributed outside of the Centre for Global Health Research due to legal agreements with the Registrar General of India. Access to MDS data can be granted via data transfer agreements, upon request to the Office of the Registrar General, RK Puram, New Delhi, India (rgoffice.rgi@nic.in). The public census reports can be found at http://www.censusindia.gov.in/vital_statistics/SRS_Statistical_Report.html. Source data files have been provided for Figure 3, Figure 3 - figure supplement 1, Figure 3 - figure supplement 2, Figure 4, Figure 4 - figure supplement 1, Figure 6, Figure 6 - figure supplement 1, and Figure 8. Meta-analyses include only previously published data, and all data sources have been listed in supplemental reference lists within the article file.
Article and author information
Author details
Funding
Canadian Institutes of Health Research (FDN154277)
- Prabhat Jha
Bill and Melinda Gates Foundation
- Prabhat Jha
National Institutes of Health (R01TW05991-01)
- Prabhat Jha
The funders had no role in study design, data collection, analysis or interpretation, preparation of the manuscript or the decision to submit the work for publication.
Copyright
© 2019, Farrar et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Seasonal variation and etiologic inferences of childhood pneumonia and diarrhea mortality in India
eLife 8:e46202.
https://doi.org/10.7554/eLife.46202
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