Date of Award

January 2015

Document Type

Open Access Thesis

Degree Name

Master of Public Health (MPH)


School of Public Health

First Advisor

Albert I. Ko



Extreme weather events can precipitate epidemic transmission of diarrhea. We describe a large nationwide epidemic in the Solomon Islands following a focal flash flood disaster on April 3-5, 2015 in the capital city of Honiara.


The Early Warning Alert and Response Network surveillance system (EWARN) detected an outbreak of diarrhea in Honiara. We identified cases from EWARN and retrospective review of outpatient registries in Honiara prior to and during the outbreak. We reviewed data from the public adverse event system to identify diarrhea-related deaths. Rapid diagnostic testing for rotavirus was performed on stool samples from cases. RT-PCR analysis was used to genotype rotavirus isolates.


We identified 4,231 cases of diarrhea in the city of Honiara (pop. 64,609) during an epidemic which occurred following massive flooding. The mean weekly incidence of diarrhea increased from 21.6 to 43.7 cases per 10,000 population during the period before and after flooding. Although flooding was limited to Honiara and the province of Guadalcanal, hospital-based surveillance detected increase in weekly cases of diarrhea in 4 additional provinces situated on separate islands. Peak weekly incidences in these provinces occurred 4-10 weeks after the peak of the outbreak in Honiara. The highest attack rates for diarrhea in Honiara and nationwide were observed in children with age <5 years. In total, 27 children died due to diarrhea related causes, which exceeded the 22 deaths directly attributed to the flash flood emergency. Rotavirus was identified in 26 of 61 (43%) of the outbreak cases for which testing was performed. All four isolates that were genotyped were found to be serotype G9P8.


Our findings indicate that a disaster sparked a large nationwide epidemic of diarrhea which spread rapidly across islands unaffected by the flood event. Although laboratory testing was limited, rotavirus appears to be an important pathogen in this outbreak. Outbreaks caused by extreme weather events carry a significant burden and should be given large consideration when describing the health impacts of climate change.


This is an Open Access Thesis.

Open Access

This Article is Open Access