Use of systematic epidemiological methods in outbreak investigations from India, 2008–2016: A systematic review

BACKGROUND: In the absence of a comprehensive review, we conducted a systematic review on the use of systematic approach in outbreak investigation using reports from India. OBJECTIVES: The primary objective was to estimate the proportion of outbreak reports from India during 2008–16, that reported the steps in outbreak investigation. The secondary objectives were to (1) describe the outbreak reports by selected characteristics (source, investigating agency, disease, time, place and person) (2) estimate the proportion of outbreaks that conducted analytical and additional studies. METHODS: We searched eight electronic databases and grey literature for outbreak investigation reports among humans at community settings from India during 2008–2016. We developed a check-list based on the 10-steps approach used by Field Epidemiology Training Programme (FETP) of ICMR-National Institute of Epidemiology (ICMR-NIE), Chennai, India. This checklist was used to independently screen and extract data on general characteristics of the outbreak investigation reports and the steps completed. We adopted The Joanna Briggs Institute (JBI) check list for prevalence studies to examine the credibility and consistency. The protocol was registered at Prospero (CRD42017065038). We calculated proportion of reports that followed the steps in their investigation and descriptive statistics on selected characteristics. RESULTS: Of 10,657 articles screened, 136 articles were included for the review. Completion of the ten steps in the outbreak investigations was seen in 16% of reports. The highest level of completion was for drawing conclusion in outbreak investigation (98%) and the lowest completion (29%) was for developing a case definition by time, place and person followed by conducting an analytic study (24%). CONCLUSIONS: Outbreak reports from India either lacked application of systematic steps for investigation or failed to report the actual procedures followed. We recommend improving systematic investigation of outbreaks through training and supervision of outbreak response teams and encouraging publications.