Joint symptoms after a large waterborne gastroenteritis outbreak--a controlled, population-based questionnaire study

Area of Science:

• Environmental Health
• Epidemiology
• Rheumatology

Background:

• Waterborne outbreaks provide unique opportunities to investigate simultaneous exposures and subsequent health effects.
• A 2007 gastroenteritis outbreak in Finland, caused by fecal contamination of tap water, served as a case study.
• Understanding the link between water contamination and joint symptoms is crucial for public health.

Purpose of the Study:

• To evaluate the occurrence of joint symptoms after a specific waterborne gastroenteritis outbreak.
• To determine the association between exposure to contaminated water and the development of joint complaints.
• To identify risk factors for joint symptoms in the aftermath of a public health crisis.

Main Methods:

• A controlled, population-based questionnaire survey was conducted.
• Residents from contaminated, uncontaminated, and control areas were randomly selected (n=1000 each).
• Joint symptoms were analyzed, with arthritis-like symptoms defined by swelling, redness, warmth, or pain during movement.

Main Results:

• The prevalence of joint symptoms was significantly higher in the contaminated group (13.9%) compared to uncontaminated (4.3%) and control (1.5%) groups.
• Arthritis-like symptoms were also more frequent in the contaminated group (6.7%).
• Gastrointestinal symptoms, particularly diarrhea and bloody stools, predicted joint complaints, and residing in the contaminated area increased the risk of joint symptoms (OR=4.0) and joint pain (OR=7.3) even without prior gastroenteritis.

Conclusions:

• The study found a high frequency of joint symptoms in the group exposed to contaminated water.
• Joint symptoms were also elevated in the uncontaminated area, suggesting potential wider impacts.
• Exposure to contaminated water increased the risk of joint symptoms, independent of gastrointestinal illness.