Inactivation of Ebola virus with a surfactant nanoemulsion.

Hemorrhagic fever caused by Ebola virus (EBO) is a highly contagious infection. This necessitates that the contaminated instruments, clothes, and hospital premises must be completely disinfected. Nanoemulsions are a new form of disinfectant composed of detergents and vegetable oil suspended in water. The antiviral activity of nanoemulsion ATB has been investigated against EBO. The nanoemulsion was tested against two preparations of EBO (strain Zaire) obtained from Vero cell culture fluid (EBO-zc) and from blood of infected monkeys (EBO-zb). The nanoemulsion ATB was virucidal against both preparations of EBO, inactivating the purified virus within 20 min even when diluted 1:100 with the growth medium. Inactivation of the virus in tissue preparations was also complete, but required 1:10 dilutions with media or higher. After treatment with ATB (10 and 1% concentrations), no EBO was apparent even after two passages in Vero cell culture. These data indicate that the nanoemulsion is an effective disinfectant for EBO. Because of the excellent biocompatibility of nanoemulsions, studies are planned to determine whether the nanoemulsion-killed virus is suitable for developing a vaccine against EBO.

[Titration of Ebola and Marburg viruses by plaque formation under semi liquid agar]. / Titrovanie virusov Ebola i Marburg po bliashkoobrazovaniiu pod poluzhidkim agarovym pokrytiem.

The method of titration of Ebola and Marburg viruses using plaque formation under semifluid agar cover is considered. Advantages of this method over conventional method of titration of these viruses with the use of hard agar cover are discussed.

[Effects of hyaluronic acid preparation on the development of herpetic infection in cell culture]. / Vliianie preparata gialuronovoi kisloty na rasvitie gerpeticheskoi infektsii v kul'ture kletok.

Cell culture experiments demonstrated antiviral activity of a new hyaluronic acid preparation towards HSV-2. The active concentration of hyaluronic acid is at least 5%.

[Assay for level of Marburg virus in blood and isolates from experimentally infected animals]. / Opredelenie soderzhaniia virusa Marburg v krovi i vydeleniiakh éksperimental'no infitsirovannykh zhivotnykh.

Measurements of concentrations of Marburg virus in guinea pig saliva, urine, and feces showed that as early as by the end of incubation period the virus concentrations in the feces and saliva were 2.3-3.3 lg LD50. In the blood the content of the virus was high and increased by the end of the disease, while the concentrations in the urine, saliva, and feces were virtually the same throughout the disease.

[Methods for controlling colonization of air and laboratory surfaces by pathogens of certain especially dangerous viral infections]. / Metody kontrolia obsemenennosti vozdukha i poverkhnostei pomeshchenii vozbuditeliami nekotorykh osobo opasnykh virusnykh infektsii.

Regular check-ups of the laboratory environment (air and working surfaces) for contamination with the objects of investigations are obligatory for laboratories working with viruses causing grave diseases, such as Ebola, Marburg, and Machupo fevers and Venezuelan equine encephalomyelitis. Methods for indication and identification of these agents have been developed and experimentally tried.

[Study of the phagocytic ability of blood polymorphonuclear leukocytes from rabbits and guinea pigs upon administering Ebola virus]. / Issledovanie fagotsitarnoi sposobnosti polimorfnoiadernykh leikotsitov krovi krolikov i morskikh svinok pri vvedenii virusa Ebola.

Study of the phagocytic activity of polymorphonuclear leukocytes (PMNL) of rabbits resistant to Ebola virus and guinea pigs susceptible to it, repeatedly challenged with live or inactivated Ebola virus in accordance with the immunization protocols, showed a much higher phagocytic activity in animals resistant to the virus than in those susceptible to it. Such behavior of PMNL in guinea pigs may be explained by the absence of the necessary cytokine background activating the neutrophils.

[Growth of organ cultures of mouse liver infected with Coxsackie A13 virus]. / Nekotorye osobennosti rosta organnoi kul'tury pecheni myshei, infitsirovannykh virusom Koksaki A13.

Peculiarities attending the growth and proliferation of the organ cultures of the liver of mongrel albino mice infected once with Coxsackie A-13 virus were investigated. A marked zone of growth, mostly of the epithelial cells, was determined rather early in the liver explants of mice in the experimental group, whereas in control group of mice the cell growth around the explant of the liver was either absent or very weak. Besides, a great number of lymphocytes evenly arranged in the zone of hepatocytes growth was observed in the preparations of the experimental mice liver. Lymphocyte "adhesion" to hepatocytes of the culture was revealed in some preparations. Moreover, destruction of the hepatocytes and a marked rarefaction of the cell layer occurred at the sites of lymphocytes accumulation on the 21st and the 28th days of growth.