The association between rainfall rate and occurrence of an enterovirus epidemic due to a contaminated well

Abstract

Aims: To determine the association between rainfall rate and occurrence of enterovirus infection related to contamination of drinking water. Methods and Results: One fatality case and three cases of severe illness were observed during the enterovirus epidemic in a village in southern Taiwan from 16 September to 3 October 1998. Groundwater samples were collected from the public well in the village after heavy rainfall to test for enterovirus using the reverse transcription‐polymerase chain reaction (RT‐PCR) assay. The RT‐PCR assay detected the enterovirus in the groundwater sample collected on 26 September 1998. The logistic regression model also revealed a statistically significant association between the rainfall rate and the observation of cases of enterovirus infection. Conclusions: According to the fitted logistic regression model, the probability of detecting cases of enterovirus infection was greater than 50% at rainfall rates >31 mm h−1. The higher the rainfall rate, the higher the probability of enterovirus epidemic. Significance and Impact of the Study: Contamination of drinking water by the enterovirus may lead to epidemics that cause deaths and severe illness, and such contamination may be caused by heavy rainfall. The major finding in this study is that the enterovirus could be flushed to groundwater in an unconfined aquifer after a heavy rainfall. This work allows for a warning level so that an action can be taken to minimize future outbreaks and so protect public health.

Associations between Meteorological Factors and Aseptic Meningitis in Six Metropolitan Provinces of the Republic of Korea

“…In our study, AM cases varied seasonally in the 6 metropolitan provinces, occurring mostly in the summer months and peaking in July. This is similar to other Korean studies [7,24,25,26] and could be due to the factors such as viral strains, climate, season, geography, crowding, and socioeconomic status, which are shown to alter the prevalence and transmission of EVs in other countries [3,5,6,7]. Because the enteroviral diseases are most prevalent among children, it is also possible that outdoor play activities, which occur more often in summer than in winter, could facilitate EV transmission.…”

“…An increase in the weekly lags of rainfall had a positive effect on AM cases. It is possible that rainfall could flush EVs into water bodies [6] that serve as a potential reservoir and vehicle, and thereby play an important role in infection. Solar radiation had a positive relationship with AM cases from lags 4 to 12.…”

“…Enteroviral diseases are found year-round in tropical and semi-tropical climates and primarily in the summer and fall months in temperate regions [1,2,4]. Prevalence and transmissibility vary by viral strain, climate, season, geography, crowding, and socio-economic status [4,5,6,7]. Different EVs can cause similar symptoms while a single EV can cause a range of symptoms, from undifferentiated febrile illness to undisguised aseptic meningitis (AM) [2,8].…”

Untangling the Impacts of Climate Change on Waterborne Diseases: a Systematic Review of Relationships between Diarrheal Diseases and Temperature, Rainfall, Flooding, and Drought

“…186, 187 Heavy rainfall can also lead to resuspension of pathogens in sediment, 188 or mobilization of pathogens in soils. 189 Heavy rainfall events can cause contamination of groundwater, e.g., 112 and can lead to saturation of the subsurface, 105, 110 which facilitates water transport of pathogens into surface or groundwater.…”

Association between Rainfall and Pediatric Emergency Department Visits for Acute Gastrointestinal Illness

“…Investigators in Canada found that in the last quarter of the 20th century, rainfall events above the 93rd percentile increased the risk of a waterborne disease outbreak by a factor of 2.3 (Thomas et al 2006). Disease outbreaks after heavy rainfall have been attributed to a variety of pathogens, including Cryptosporidium (Atherholt et al 1998; MacKenzie et al 1994), Giardia (Atherholt et al 1998; Weniger et al 1983), and enterovirus (Jean et al 2006). What is novel about our findings is that the observed increase in ED visits for AGI occurred in the absence of any outbreaks reported to public health authorities in our region, suggesting that rainfall-associated illness may be underestimated.…”