Fate and Transport of Zoonotic Bacterial, Viral, and - The Pork Store ...

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Fate and Transport of Zoonotic Bacterial, Viral, and Parasitic Pathogens during Swine Manure Treatment, Storage, and Land Application
ELISA (10 5 particles/g) and RT-PCR (10 1-3 particles/g)
could result in positive samples in those systems that
tested negative by ELISA. However, neither infectious
particles were detected by CCIF, nor were clinical signs
or seroconversion detected in inoculated Gn pigs. These
results indicate that only RV-A/C RNA, but no viral
infectivity, was detected after treatment, suggesting that
all techonologies were effective reducing virus infectivity
when evaluated by CCIF and Gn pig inoculation.
Inactivation
Rotaviruses are nonenveloped viruses, resistant
to inactivation by ether, chloroform, detergents, many
chemical disinfectants, and antiseptics (Abad, Pinto,
and Bosch 1998). Phenols, formalin, chlorine, and
ethanol (95%), however, have been shown to be effective
(Sattar et al. 1994; Yuan, Stevenson, and Saif 2006).
Chlorine
Chlorine is considered among the most effective
disinfectants against RV in drinking water and
wastewater. Several studies have demonstrated that
chlorine inactivation is dose-, pH-, exposure time-, and
virus type-dependent (Abad et al. 1994; Ojeh, Cusack
and Yolken 1995; Vaughn, Chen, and Thomas 1986).
The inactivation of simian RV SA-11 and HRV Wa by
chlorine was compared at 4ºC at different pHs and
doses by Vaughn, Chen, and Thomas (1986). Viruses
did not show significant differences in behavior. Both
viruses usually were more readily inactivated at pH 6.0
than at pH 8.0 when low chlorine concentrations (0.05
to 0.2 mg/l) were used. A complete (5 log10) reduction
of both was obtained within 20 seconds (sec) at all pH
levels when chlorine concentrations were increased to
0.3 mg/l. Little inactivation was observed when copper
and silver ions, in combination with low levels of free
chlorine, were assayed in water (Abad et al. 1994). In
their studies of RV inactivation, Ojeh, Cusack, and
Yolken (1995) evaluated the efficiency of chlorine on
infectivity and its correlation with the presence of viral
RNA. The authors observed that 2,500 ppm chlorine
completely destroyed the infectivity of RV as well as
viral RNA amplifiable by PCR.
ultraviolet and gamma radiation
Ultraviolet inactivation has been shown to be
effective for inactivation of RV (Battigelli, Sobsey, and
Lobe 1993; Ojeh, Cusack, and Yolken 1995; Smirnov
et al. 1991). The irradiation completely destroyed the
infectivity of RV as well as viral RNA amplifiable by
PCR, as indicated by Ojeh, Cusack, and Yolken (1995).
The effects of UV irradiation also were evaluated by
Battigelli, Sobsey, and Lobe (1993) with RV in phosphatebuffered
water. The 99.9% inactivation dose for SA-11 was
42 milliwatt (mW) sec/cm 2 , almost three times higher
than the dose required to achieve 99.9% inactivation for
hepatitis A. But all these studies were done using virus
in buffered solutions, and the influence that the presence
of solid organic material may have had, such as in fecal
suspensions or food, has not been evaluated.