Comparative survival of hepatitis A virus, poliovirus and indicator viruses in geographically diverse seawaters

Abstract

The presence and persistence of enteric viruses in sewage contaminated seawater is an important public health concern for bathing, surfing and shellfishing. In an effort to find suitable indicators of enteric viruses in seawater, we compared the survival of two groups of enteric bacteriophages. F-specific coliphages (FRNA phages) and somatic Salmonella bacteriophages (SS phages), to the survival of two human enteric viruses, hepatitis A virus (HAV) and poliovirus type 1 (PV-1), in coastal seawater from three geographic areas (So. California, Hawaii, and North Carolina) at 20°C. Concentrations of all four viruses decreased over 30 days from their initial titers and there was little difference in the survival of a particular virus among the three seawaters. However, the extent of reduction varied among the four viruses. Survival was greater for the SS phages than for any of the other viruses, with an estimated 4 log ₁₀ reduction time of about 10 weeks. FRNA phages and PV-1 were inactivated rapidly, with 4 log₁₀ reductions in −1 week. HAV reductions were intermediate between SS phages and FRNA phages, with 4 log ₁₀ reductions in about 4 weeks. The observed differences in virus survival suggest that SS phages are more persistent in seawater than other viruses and hence may be good indicators for enteric viruses in seawater.