Background: Waterborne illness is difficult to detect and frequently is identified only after widespread morbidity occurs. We implemented a sentinel surveillance system for waterborne illness and assessed the relationship between onsite water quality parameters and diarrheal illness (DI). Methods: The 15 project sites represented all 5 water distribution zones in Boston, used municipal water, and included schools, day care centers (DCC), chronic care sites, and corrections facilities. Participants were contacted weekly to determine total population size and number of persons with DI in the prior week. Reported increases in morbidity were investigated by city health department nurses to assess water as a risk factor. Weekly water samples from onsite taps were evaluated for turbidity, residual chlorine, total coliforms, and heterotrophic plate count, and were correlated with DI rates. Results: The mean weekly rate of DI among sentinel populations was <1%. Of the 6 episodes of increased morbidity identified, 5 were in DCC, most (5/6) occurred from October to January, and none were associated with drinking water. Onsite water quality parameters rarely exceeded threshold values and did not correlate with morbidity. Conclusions: The sentinel surveillance system effectively identified sporadic increased morbidity due to DI. The observed lack of correlation between water quality parameters and illness may be related to high quality drinking water, lack of exposure to drinking water, or sentinel monitoring system design. The ability of sentinel surveillance systems to detect potentially widespread outbreaks such as waterborne illness and pandemic influenza should be further explored.
Learning Objectives: Describe a sentinel surveillance system for diarrheal illness. Discuss the relationship between illness & routinely used water quality parameters
Keywords: Surveillance, Water
Presenting author's disclosure statement:
Organization/institution whose products or services will be discussed: None
I do not have any significant financial interest/arrangement or affiliation with any organization/institution whose products or services are being discussed in this session.