Dissemination Of Viral Infections Research Articles

About the influence of environmental conditions on the distribution of the SARS-CoV-19 virus in Ukraine

Taking into account that climate and atmospheric processes can, to a certain extent, affect viral epidemics, the dynamics of the rates of infection with the SARS-CoV-19 virus was analyzed in comparison with a number of climate factors (temperature, precipitation, humidity, etc.) in the territory Kiev, Dnepropetrovsk, Odessa and Khmelnytsky regions as well as the city of Kiev during April—August 2020. To assess the impact of environmental conditions on the process of virus infection, the index of confirmed cases (ICC) was introduced.It is shown that in the spring, in particular, in May, the ICC index increased with a cold snap and decreased with a warming. In summer, the ICC index decreased with an increase of temperature with a delay of infection by 5—7 days, which is apparently associated with the incubation period of the virus (5—14 days). In particular, there was no increase in ICC values at high temperatures (over 30 °C). The relative humidity of the atmosphere air and the dew point temperature are more closely related to the efficiency of virus transmission. Thus, in spring, with an increase in relative humidity, an increase in the values of the ICC index was observed, and vice versa, with a decrease in relative humidity, the ICC index decreased. In summer, at high air temperatures and fluctuations in relative humidity, the ICC index mainly decreased, with the exception of a few weather situations. A decrease in the amount of atmospheric precipitation in April-August 2020 in Ukraine affected the activity of aerosol transmission of viruses (air-dust transport prevailed). At the same time, it was found that an increase of the ICC index during rainy periods correlates with the number of days with precipitation (less — with the amount of precipitation), while there is a delay in the growth of infection rates by several days. Analysis of the possible effect of precipitation acidity on the survival of the SARS-CoV-19 virus indicates the absence of a significant effect of this factor on the dissemination of viral infection. The presented results of the analysis of data on infection with the SARS-CoV-19 virus in Ukraine indicate a certain dependence of this process on climatic factors and are important for the assessment of the risks of infection and related diseases.

Моніторинг розповсюдження вірусів серед домашніх котів і собак у м. Дніпропетровськ

Cats and dogs kept at home, as well as other animals, are susceptible to infectious diseases caused by pathogenic microorganisms, including viruses. Viral infections in urban environments are extremely common and cause severe diseases in domestic animals which often lead to death, resulting in high material and moral damages to owners of animals. Therefore, investigation of the prevalence of pathogens of viral diseases is very important in our time. The aim of this work is to define the indicators of spreading viral diseases of animals in Dnipropetrovsk, to analyze the seasonal spread of viral infections in animals, and influence of sex and breed on the frequency of disease manifestations. Materials for research were obtained on the basis of three veterinary clinics in Dnipropetrovsk. During the study, we used serological methods of diagnostics of clinical materials, namely ELISA and IHA. Immunosorbent assay was performed using the thermostatic shaker ST-3 and strip immunoassay analyzer Stat Fax 303 Plus. Also we used commercial test systems VetExpert CAV Ag and Feline VacciCheck ImmunoComb®, based on the immuno-chromatographic method. During clinical studies of 491 animals (268 cats and 223 dogs) it was found that the most common respiratory viral infections in cats were calicivirus infection and rhinotracheitis, while in dogs there were viral diseases of gastrointestinal tract, i.e. enteritis and hepatitis. Using IHA method, we revealed the antibodies to respiratory viruses in the blood of deseased cats: to calicivirus – in 95 cats, to rhinotracheitis – in 60 cats; by ELISA method we identified antigens of parvovirus, enteritis pathogen, in biological material of 61 dogs, by IHA we found antibodies to virus of infectious hepatitis in 49 individuals. Based on these data, it has been revealed that during the winter months the animals suffered mostly the respiratory viral infections (60%), and in spring there were increased occur-rence of enteritis, observed in all age groups of animals. From May, hepatitis started to appear and prevailed for all summer months, mixed with enteritis (about 50% of total number of cases). Hepatitis was recorded both in cats and dogs. By the fall, recurrence was observed for calicivirus and herpes virus infections in cats, and the cases of enteritis decreased, while hepatitis was recorded until mid-October. Such statistics is kept relatively constant. The research results can be applied in the practice of veterinary laboratories for the development of diagnostic measures and prevention of viral diseases in domestic animals, as well as in the prediction of dissemination of viral infections in animals in the near future.

Severe encephalitis resulting from coinfections with HIV and JC virus

We observed 3 cases of progressive multifocal leukoencephalopathy (PML) among frozen CNS samples obtained at autopsy from 102 adult AIDS patients. In 2 patients, PML was associated with severe HIV encephalitis. In those 2 cases, the areas of extensive JC-induced demyelination were massively infiltrated by HIV infected macrophages/microglial cells with evidence for localized increase of HIV encephalitis in PML lesions. Using immunohistochemistry and in situ hybridization, we demonstrated that each virus infects, in a latent or productive fashion, different CNS cell populations. Therefore, the extension of HIV encephalitis could not be related to an intracellular transactivation of 1 virus by the other. However, the results are consistent with dissemination of viral infection by the recruitment of HIV-infected macrophages to damaged areas of the brain. This phenomenon might be generalized to other pathogens that are frequently associated with HIV CNS infection. Early detection and treatment of opportunistic CNS lesions could be important to prevent extension of HIV encephalitis.