Post-infection symptoms following two large waterborne outbreaks of Cryptosporidium hominis in Northern Sweden, 2010–2011

Abstract

BackgroundIn 2010–2011, two large waterborne outbreaks caused by Cryptosporidium hominis affected two cities in Sweden, Östersund and Skellefteå. We investigated potential post-infection health consequences in people who had reported symptoms compatible with cryptosporidiosis during the outbreaks using questionnaires.MethodsWe compared cases linked to these outbreaks with non-cases in terms of symptoms present up to eleven months after the initial infection. We examined if cases were more likely to report a list of symptoms at follow-up than non-cases, calculating odds ratios (OR) and 95 % confidence intervals (CI) obtained through logistic regression.ResultsA total of 872 (310 cases) and 743 (149 cases) individuals responded to the follow-up questionnaires in Östersund and Skellefteå respectively. Outbreak cases were more likely to report diarrhea (Östersund OR: 3.3, CI: 2.0-5.3. Skellefteå OR: 3.6, CI: 2.0-6.6), watery diarrhea (Östersund OR: 3.4, CI: 1.9-6.3. Skellefteå OR: 2.8, CI: 1.5-5.1) abdominal pain (Östersund OR: 2.1, CI: 1.4-3.3, Skellefteå OR: 2.7, CI: 1.5-4.6) and joint pain (Östersund OR: 2.0, CI: 1.2-3.3, Skellefteå OR: 2.0, CI: 1.1-3.6) at follow-up compared to non-cases.ConclusionsOur findings suggest that gastrointestinal- and joint symptoms can persist several months after the initial infection with Cryptosporidium and should be regarded as a potential cause of unexplained symptoms in people who have suffered from the infection.Electronic supplementary materialThe online version of this article (doi:10.1186/s12889-015-1871-6) contains supplementary material, which is available to authorized users.

Persisting post-infection symptoms 2 years after a large waterborne outbreak of Cryptosporidium hominis in northern Sweden

“…Eight hundred seventy-two of those subjects also took part in a questionnaire-based follow-up investigation [9], and, 25 January 2013, we invited those respondents to complete another follow-up questionnaire regarding post-infection symptoms during the 3 months preceding the day of answering the questionnaire. Responses were recorded until 25 February 2013, and hence the period of recorded post-infection symptoms in the Östersund study was 25 October 2012 to 25 February 2013.…”

“…A follow-up evaluation of the affected population revealed that outbreak cases were more likely to have gastrointestinal and joint-related symptoms up to 11 months after the initial infection [9]. We performed an additional follow-up investigation of the study population in Östersund to ascertain whether the symptoms were persisting 2 years after the outbreak occurred.…”

Hund som Giardia-kilde i Bergen i 2004 – barking up the wrong tree?

“…I en studie av mennesker smittet med Giardia (vel å merke ikke i sammenheng med utbrudd) i USA ble det vist at ekstraintestinale symptomer var relativt vanlig (23). Det er også verdt å merke seg at det vannbårne utbruddet av kryptosporidiose i Östersund også ble assosiert med langvarige gastrointestinale symptomer og leddplager (24).…”

Prevalence of Dientamoeba fragilis, Giardia duodenalis, Entamoeba histolytica/dispar, and Cryptosporidium spp in Da Nang, Vietnam, detected by a multiplex real‐time PCR

“…Cryptosporidium spp has been recognized as the cause of large waterborne and food‐borne outbreaks of gastroenteritis with long term complications and long‐lasting symptoms . C. spp .‐associated diarrhea has become well known as a result of the severe manifestations in AIDS patients, and subsequently improved diagnostic methods were developed .…”