Sunlight inactivation of Campylobacter jejuni and Salmonella enterica, compared with Escherichia coli, in seawater and river water

J Water Health. 2007 Sep;5(3):357-65. doi: 10.2166/wh.2007.031.

Abstract

The inactivation of Campylobacter jejuni and Salmonella enterica, compared with Escherichia coli, was determined in 100 l chambers of seawater and river water located at an outdoor site. The chambers (paired with dark controls) were seeded with waste stabilization pond effluent and laboratory-cultured pathogens, and exposed to sunlight in summer and winter experiments. All sunlight inactivation (k(S)) rates, as a function of cumulative global solar radiation (insolation), were far higher than the corresponding dark (k(D)) rates, with a ranking (and average k(S) rates for seawater and river water, respectively) of: C. jejuni (3.23; 2.34)>S. enterica (0.51; 0.37)>E. coli (0.34; 0.26). All the T(90) (time to 90% inactivation) values were higher in winter than in summer, but there was far greater similarity between the summer and winter S(90) (insolation needed for 90% inactivation) values. The rapid inactivation of C. jejuni was attributed to a high susceptibility to photooxidative damage. The results suggest that, in sunlight-exposed waters, E. coli will be a more conservative indicator for C. jejuni than for S. enterica, and C. jejuni transmission as a pathogenic agent is less likely than for S. enterica.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Campylobacter jejuni / growth & development
  • Campylobacter jejuni / radiation effects*
  • Disinfection / methods
  • Escherichia coli / growth & development
  • Escherichia coli / radiation effects*
  • Rivers / microbiology
  • Salmonella enterica / growth & development
  • Salmonella enterica / radiation effects*
  • Seawater / microbiology
  • Sunlight*
  • Water Microbiology
  • Water Pollutants / radiation effects*

Substances

  • Water Pollutants