Comparison of pathogen-derived 'total risk' with indicator-based correlations for recreational (swimming) exposure.

Typical recreational water risk to swimmers is assessed using epidemiologically derived correlations by means of fecal indicator bacteria (FIB). It has been documented that concentrations of FIB do not necessarily correlate well with protozoa and viral pathogens, which pose an actual threat of illness and thus sometimes may not adequately assess the overall microbial risks from water resources. Many of the known pathogens have dose-response relationships; however, measuring water quality for all possible pathogens is impossible. In consideration of a typical freshwater receiving secondarily treated effluent, we investigated the level of consistency between the indicator-derived correlations and the sum of risks from six reference pathogens using a quantitative microbial risk assessment (QMRA) approach. Enterococci and E. coli were selected as the benchmark FIBs, and norovirus, human adenovirus (HAdV), Campylobacter jejuni, Salmonella enterica, Cryptosporidium spp., and Giardia spp. were selected as the reference pathogens. Microbial decay rates in freshwater and uncertainties in exposure relationships were considered in developing our analysis. Based on our exploratory assessment, the total risk was found within the range of risk estimated by the indicator organisms, with viral pathogens as dominant risk agents, followed by protozoan and bacterial pathogens. The risk evaluated in this study captured the likelihood of gastrointestinal illnesses only, and did not address the overall health risk potential of recreational waters with respect to other disease endpoints. Since other highly infectious pathogens like hepatitis A and Legionella spp. were not included in our analysis, these estimates should be interpreted with caution.

The psychological impact of mass casualty incidents on first responders: A systematic review.

First responders are exposed to various types of disasters throughout their career. Because of their roles, they are often regarded as stronger people than individuals from other occupations. A systematic review of literature was conducted to determine if distinct characteristics exist that make first responders more susceptible to psychological trauma. Five categories of traits were found to put first responders at risk for psychological problems: personal, predisposing, peridisposing, postdisposing, and protective. To counteract the impact of psychological trauma, first responders need additional preincident psychological and resiliency training. Preparedness and awareness will help combat psychological impact from disasters and compassion fatigue.