Survival of Human Enteroviruses in the Hawaiian Ocean Environment: Evidence for Virus-inactivating Microorganisms

The stability of certain human enteroviruses in the Hawaiian ocean environment was examined. The present data indicated that the time for 90% reduction of poliovirus type 1 at 24 +/- 1 degree C in seawater samples obtained from different sites in Hawaii ranged from 24 to 48 h, and complete inactivation occurred within 72 to 96 h. The accumulated evidence also strongly indicated that a virus-inactivating agent(s) of a microbiological nature was present in both clean and sewage-polluted seawaters, but not in fresh, mountain stream waters. The antiviral activity was lost when the seawater samples were subjected to boiling, autoclaving, or filtration through a 0.22- or 0.45-micrometer, but not a 1.0-micrometer, membrane filter. That the antiviral activity of the seawater was related to the growth activities of microorganisms was corroborated by the observed effects of added nutrients, a lower temperature of incubation, and the presence of certain antibiotics. Other enteric viruses, such as coxsackie virus B-4 and echo virus-7, were also shown to be similarly inactivated in seawater.