Summary of number of illnesses and deaths by causative microorganism as reported in 293 waterborne disease outbreaks involving small drinking water systems in Canada and the United States (1970–2014).

1Attack rate was not included as it was not available for the majority of outbreak reports2Other microorganisms included Salmonella spp., Small Round Structured Viruses (SRSV), Rotavirus, Yersinia enterocolitica, Streptococcus spp., Bacillus cereus and Pseudomonas aeruginosa3Unknown was not reported4Count exceeds the total number of people ill due to illness associated with multiple agentsSummary of number of illnesses and deaths by causative microorganism as reported in 293 waterborne disease outbreaks involving small drinking water systems in Canada and the United States (1970–2014).