Development of a simple method for concentrating enteroviruses from oysters

The development of a simple method for concentrating enteroviruses from oysters is described. In this method viruses in homogenized oyster tissues are efficiently absorbed to oyster solids at pH 5.5 and low salt concentration. After low-speed centrifugation, the supernatant is discarded and viruses are eluted from the sedimented oyster solids by resuspending them in pH 3.5 glycine-buffered saline. The solids are then removed by low-speed centrifugation, and the virus-containing supernatant is filtered through a 0.2-micronm porosity filter to remove bacteria and other small particulates without removing viruses. The virus-containing filtrate is then concentrated to a volume of a few milliliters by ultrafiltration, and the concentrate obtained is inoculated directly into cell cultures for virus assay. When tested with pools of oysters experimentally contaminated with small amounts of different enteroviruses, virus recovery efficiency averaged 63%.

Isolation of acid-fast organisms from milk and oysters

Raw and pasteurized milk, as well as oysters collected from approved growing areas, were cultured for the presence of acid-fast organisms. Mycobacteria and nocardia were isolated from 68.8% of the raw milks, but none from the 43 pasteurized specimens. The 66 isolations were identified as follows: one M. marinum, two M. scrofulaceum, nine M. gordonae, seven M. flavescens, nine M. avium---M. intracellulare complex, 18 M. terrae complex, 12 M. fortuitum, six M. "parafortuitum" complex, and two Nocardia asteroides. From nine pooled samples of oysters 15 mycobacterial strains were cultured. These strains were identified as follows: three M. scrofulaceum, five M. gordonae, two M. avium--M. intracellulare complex, two M. terrae complex and three M. "parafortuitum" complex.

Survey on the incidence of Yersinia enterocolitica infection in Canada

Data pertaining to 278 cultures of Yersinia enterocolitica isolated in Canada are summarized in this paper. Of this amount, 256 were isolated from humans, whereas 22 were of nonhuman sources. The typing of these cultures is presented together with their geographical location. Y. enterocolitica serotype O:3 biotype 4, phage type 9b, was practically the only serotype present in the Province of Quebec. This serotype O:3 was also predominant in Ontario, followed by serotypes O:5,27 and O:6,30; other serotypes were seldom isolated. In the central and western areas of Canada, Y. enterocolitica was occasionally isolated; the strains were indole-positive, serotypes O:5,27, O:8, and O:4,32.