Kenneth W. Cochran

Rubella Virus: Inhibition in vitro by Amantadine Hydrochloride

Amantadine (or 1-adamantanamine) hydrochloride, a compound reported to be active against influenza viruses and Sendai virus, inhibited the growth of rubella virus in tissue culture. The antiviral activity appears at an early phase of the infection and is not due to direct inactivation of the virus.

Field studies on coliphages and coliforms as indicators of airborne animal viral contamination from wastewater treatment facilities

The occurrence of animal viruses in the aerosol emissions of wastewater treatment facilities was evaluated by direct assay and by the use of coliforms and coliphages as indicator organisms. Coliforms and coliphages were compared and evaluated with regard to their suitability as indicators of airborne animal viral contamination from wastewater treatment facilities. Two plants, one with treatment by activated sludge and the other by trickling filtration, were studied. Field air sampling procedures used large-volume air samplers, with recirculation devices, and Andersen samplers. Airborne viruses were enumerated by a most probable number (MPN) procedure. Partially treated liquid sewage contained about 1.0x 102 pfu 1-~ of animal viruses assayed on Buffalo Green IVlonkey (BGM) cells, 3.6 x 105 and 5.0 x 105 pfu I - t of coliphages, depending upon the E. coli host strain used for assay, and 2.0 x 10 9 colonies 1-~ of coliform bacteria. No airborne animal viruses were recovered, airborne coliphage levels averaged 2.3 x 10 -t and 3.0 x 10 -t MPNm -3, coliforms from aerosol emissions were 2.1 x 102 colonies m -3. Ratios of coliphages to animal viruses indicate that wastewater treatment plants may be continuous sources of low level concentrations of animal virus aerosols. Evidence shows coliforms to be much less stable than coliphages in the airborne state. Coliphages may be a more acceptable indicator of airborne animal viral contamination than coliforms.

Isolation and antiviral activity of the gymnemic acids

Aus den Blättern vonGymnema sylvestre wurden 4 Gymneasäuren (A, B, C und D) isoliert. Die Antivirusaktivität der Säuren A und B wurde geprüft.

Rotavirus and reovirus stability in microorganism-free distilled and wastewaters

Survival of calf rotavirus and reovirus under controlled laboratory conditions in micro- organism-free, distilled and wastewater at 8 and 26°C was examined by periodic measurement of cyto- pathic effects (CPE) and indirect fluorescent antibody (IFA) assays. Five samples of both water-types were collected and inoculated with the two viruses. Three samples of each type of water were divided into two bottles, one per virus, for incubation at 8°C. Two samples were used at 26°C, one per trial. In the absence of light and shaking at 26°C, 7 13 days were required for a loss of 90~o infectivity for rotavirus and reovirus, while at 8°C, averages were 80 days for rotavirus and 260 days for reovirus. Virus infectivity remained for more than 30 days at 26°C and 400 days at 8°C. Rates of decline were 10-100 times greater at 26 than at 8°C, but at both temperatures, the MPN log10 rate of decline of infectivity was linear.

Differential and Specific Inhibition of ECHO Viruses by Plant Extracts.

Summary 1) Comparison of antiviral activity of several plant extracts against several ECHO viruses revealed that M2, prepared from a strain of Calvatia gigantea significantly inhibited only ECHO 4 and 11; while M4, a different preparation from the same strain, inhibited only ECHO 7 and 8; and M14, from a species of Cattleya, inhibited ECHO 2. The effectiveness of M2 in vitro was greatest when the cells were pretreated and when the virus inocula did not exceed 100 TCID50. 2) Specificity of the antiviral action of M2 was demonstrated by inhibition of one M2-susceptible virus followed in the same culture by growth of a second M2-nonsusceptible virus. Inhibition continued, however, if the cultures were reinoculated with a second M2-susceptible virus. 3) Activity of M2 was demonstrated in vivo by its ability to suppress the antigenicity of an M2-susceptible virus. 4) The results demonstrate strikingly the capacity of the materials to prevent infection of susceptible cells by specific viruses although the cells retain their physiologic competence to support growth of other viruses and the virus is not directly affected by the inhibitory material. Obviously the effect must be directed to modification of reactions essential to viral development but not injurious to functional integrity of the cell.

Antiviral Action of a Mold Filtrate on Experimental Poliomyelitis in Gynomolgus Monkeys.

Summary The crude filtrate of a penicil-lium mold, M-8450, was shown to have antiviral action in cynomolgus monkeys inoculated subcutaneously with the Mahoney strain of Type 1 poliomyelitis. Treatment with at least 100 ml of this crude filtrate reduced the morbidity and increased the incubation period of infected animals. Less intensive treatment appeared to be less effective. The antiviral action of this substance appears to merit further study.

Antiviral action of helenine on experimental poliomyelitis.

Summary Helenine, an antiviral agent derived from P. funiculosum, was found to have marked prophylactic activity in cynomolgus monkeys infected with poliomyelitis virus.

Susceptibility of a Strain or Rat Virus to Statolon and Other Virus Inhibitors.

Summary Rat virus, strain XI4, a small (22 m/x) virus isolated from the mammary tissue of an X-irradiated rat, was found to be inhibited by statolon and by guanidine. Since statolon, a penicillium-derived antibiotic previously had been found to inhibit RNA viruses of the arbor- and entero-groups, it is noteworthy that rat virus was also inhibited by 5-fluoro-2-deoxyuridine and that the inhibition was prevented by thymidine, a conventional identification of a DNA virus.

Loss of infectivity of poliovirus 1 in river water under simulated field conditions

Abstract The effects of light, virus concentration, and turbidity on the rate of loss of infectivity (LOI) of poliovirus 1 were investigated in two test systems, which utilized flowing river water. Two levels of each variable were used in a 23 confounded factorial design. The seeded systems were sampled at regular intervals to establish LOI rates. Virus infectivity was measured by plaque assay. Loss of infectivity followed a two-component curve; an initial, rapid phase followed by a second, slower component. The slopes of the two components were examined by the analysis of variance to determine the potential influence of each variable. Both light and turbidity exerted a significant influence on the LOI rate in the second component of the LOI curve and also in the transition period between the two components; however, during the initial, rapid phase none of the variables influenced the LOI rate (at the 0.05 significance level). This research demonstrates the significance of light as a virucidal component in the aquatic environment.

Influence of 5-Fluorodeoxyuridine on Growth Characteristics of Rubella Virus.

Summary Rubella virus grows to a maximum titer of approximately 10-5.0 Int.D.50 in LLC-MK2 cell cultures, with 2:1 input in50 multiplicity. There is always cell-associated virus which accounts for a small portion of the infectious yield. 5-FUDR did not affect in any way the yield of rubella virus as compared to the untreated control. Rubella virus therefore appears to belong to the RNA viruses. The authors are indebted to the Cancer Chemotherapy Service Center for 5-FUDR. The technical assistance of Miss Patricia Gosnell is gratefully acknowledged.