Linking human health effects to water quality using a rapid, noninvasive salivary-IgG antibody multiplex immunoassay
Understanding and curbing the mounting global increase in waterborne pathogen outbreaks are quickly becoming major priorities for public health professionals and policy makers. According to the World Health Organization (WHO), 60% of global diarrheal deaths are caused by unsafe water and lack of sanitation or hygiene. The WHO estimates that at least 2 billion people use a drinking water source contaminated with feces. Contaminated water -- shown to transmit diseases such as diarrhea, cholera, dysentery, typhoid, hepatitis A, and polio -- is estimated to cause almost half a million diarrheal deaths each year. The United States Environmental Protection Agency has prioritized efforts to understand the links between water quality and human health effects. To that end, we have developed and applied a salivary-IgG antibody multiplex immunoassay to measure human exposures and associated health effects to multiple pathogens simultaneously. Saliva is emerging as a cost-effective, noninvasive biofluid that is well-accepted by children. The multiplex immunoassay has afforded the ability to assess immunopositivity, immunoprevalence, co-infections and incident infections (immunoconversions) to Helicobacter pylori, Campylobacter jejuni, Cryptosporidium parvum, Toxoplasma gondii, hepatitis A virus and noroviruses GI.I and GII.4 at several beaches throughout the US. Further, we’ve found evidence of asymptomatic norovirus and hepatitis A infections in visitors to a fecally contaminated beach. The assay produces results in as little as one hour and when used in conjunction with epidemiologic and water quality studies, provides valuable information that links human health effects more directly to water quality.