Two media for preserving the viability of different viruses in clinical material during transit at ambient temperature have been developed. One was designed for transporting stool specimens and autopsy material, while the other was designed for such specimens as throat washings, swabs, and cerebrospinal fluid. The essential ingredient in both media was bentonite either uncoated or coated with serum proteins. Preparation of both media is given in detail.Experimental results presented indicate that coxsackie A9, B5, echo 11, adeno 5, influenza A2, parainfluenza, rubella, and herpes simplex viruses could sustain their infectivity without loss of titer in bentonite transport medium for prolonged time, from 3 to 21 days, depending on the virus type.The bentonite transport medium was found to be superior to commonly used charcoal viral transport medium.

In late October 1991, an outbreak of gastroenteritis, following the consumption of raw oysters involving more than 200 people, was reported in five locations in Quebec, Canada. Bacteriological analysis of the oysters involved indicated low levels of fecal coliforms, but direct electron microscopy of stool samples obtained from two people involved in the outbreak revealed that both contained 27–34 nm, small, round Norwalk-like viruses. Immunoelectron microscopy, using acute sera obtained from these individuals and convalescent serum from another person related to the outbreak, revealed antibody coatings on these Norwalk-like viruses with all three sera. Solid-phase immunoelectron microscopy demonstrated that these viruses were also antigenically similar or related to a Norwalk-like virus isolated as the cause of a gastroenteritis outbreak in a home for the aged between December 1988 and January 1989 in Thunder Bay, Ontario. From these findings and the symptoms of the illness, the Norwalk-like virus was considered as the causal agent of the outbreak due to the consumption of contaminated oysters. How the oysters became contaminated was not determined. Oysters harvested from the areas initially thought to have been the origin of the implicated shellfish were tested for the presence of viral fecal indicators using tissue culture and electron microscopy with negative results. It is most likely that the implicated lot also contained oysters harvested from another area, also open, but which was downstream from an identified source of human fecal contamination.

Two ELISA systems for the detection of human rotaviruses were developed. In the first system antibodies to Nebraska calf diarrhea virus (NCDV) were used for coating the solid matrix and for the preparation of the enzyme conjugate. In the second system antibodies to human rotavirus and antibodies to simian rotavirus (SA11) were used for coating the solid matrix and for the preparation of the enzyme conjugate respectively. The second ELISA system proved to have a broader spectrum for the detection of human rotaviruses. By using the two ELISA systems, the different types of human rotavirus could be distinguished. The ELISA tests developed were 8 to 64 times as sensitive as electron microscopy (EM) and (or) counterimmunoelectrophoresis (CIEP). The antigen detected by ELISA was shown to be different from that detected by the hemagglutination test.

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