The data are stored as a SAS dataset containing PII. The dataset contains baseline questionnaire, monthly follow-up questionnaire data, and results and salivary antibody tests for IgG and IgA response to selected antigens of potentially waterborne pathogens. This dataset is not publicly accessible because: EPA cannot release personally identifiable information regarding living individuals, according to the Privacy Act and the Freedom of Information Act (FOIA). This dataset contains information about human research subjects. Because there is potential to identify individual participants and disclose personal information, either alone or in combination with other datasets, individual level data are not appropriate to post for public access. Restricted access may be granted to authorized persons by contacting the party listed. It can be accessed through the following means: See above. Format: The study database include baseline questionnaire, monthly follow-up questionnaire, and results of salivary antibody tests for 1,986 study participants. The dataset contains PII data. The data are stored as a SAS database. This dataset is associated with the following publication: Egorov, A., S. Griffin, H. Ward, K. Reilly, G.S. Fout, and T. Wade. Application of a salivary immunoassay in a prospective community study of waterborne infections. WATER RESEARCH. Elsevier Science Ltd, New York, NY, USA, 142: 289-300, (2018).