Survey of tick-borne relapsing fever borreliae in southern and southeastern Kazakhstan.

Tick-borne relapsing fever group borreliae (TBRFGB) are spirochetes that cause disease in humans and animals. Little is known about the prevalence of TBRFGB infections in ticks and humans in Kazakhstan. A total of 846 ticks belonging to ten species of the family Ixodidae and three species of the family Argasidae were collected from the vegetation, poultry shelters, domestic ruminants, bitten humans, pigeons, dogs and house walls in four oblasts of the southern and southeastern regions of Kazakhstan. The ticks were subjected to DNA extraction and identification of TBRFGB by conventional PCR using primers targeting flagella subunit B (flaB), glycerophosphodiester phosphodiesterase (glpQ) and P66 porin (P66) genes. The overall infection rate of TBRFGB in the ticks was 6.2 % (46/846). TBRFGB DNA was identified in Ixodes persulcatus (5.5 %; 26/477), Ornithodoros tartakovskyi (6 %; 2/36) and Argas persicus (13.4 %; 18/134) ticks. Partial sequencing of flaB, glpQ and P66 genes identified Borrelia miyamotoi in I. persulcatus and Borrelia anserina in A. persicus. To detect the presence of B. miyamotoi infection in people in the study region, we performed serological analysis of samples collected from 42 patients admitted to hospital with fever of unknown etiology or with a history of a tick bite. The analysis revealed IgM and IgG antibodies against one or several B. miyamotoi antigens in 10 % and 5 % of patients, respectively. The data obtained provide strong evidence of the presence of B. miyamotoi and B. anserina in the southern and southeastern regions of Kazakhstan, underscoring the need for increased awareness of potential infections caused by these borreliae in these regions.

Long-term changes in the phenotype and cytokine production of monocytes in COVID-19 recovered and vaccinated individuals.

Monocytes play a crucial role in the immune response against pathogens. Here, we sought to determine COVID-19 and the vaccine Gam-COVID-Vac induce long-term changes in the phenotype and cytokine production of circulating monocytes. Monocytes were purified from peripheral blood mononuclear cells of healthy donors who had not had COVID-19 or vaccination, who had received two doses of Gam-COVID-Vac, and who had mild/moderate COVID-19 in the last 6 months and evaluated by flow cytometry. To investigate the effect of SARS-CoV-2 proteins, monocytes were cultured for 2 days with or without stimulation with recombinant SARS-CoV-2 S1 and N peptides. Monocytes obtained from vaccinated and recovered individuals showed increased basal expression of HLA-DR, CD63, CXCR2, and TLR7. We also observed an increased frequency of CD63+ classical monocytes in both groups, as well as an increased frequency of HLA-DR+ non-classical monocytes in the COVID-19-recovered group compared to the control group. Monocytes from vaccinated and recovered donors produced higher basal levels of IL-6, IL-1ß, and TNF-α cytokines. Ex vivo stimulation with SARS-CoV-2 antigens induced increased expression of HLA-DR and TLR7 on monocytes obtained from the control group. The challenge with SARS-CoV-2 antigens had no effect on the production of IL-6, IL-1ß, and TNF-α cytokines by monocytes. The acquired data offer compelling evidence of enduring alterations in both the phenotype and functional status of circulating monocytes subsequent to vaccination with Gam-COVID-Vac and mild/moderate COVID-19 infection. At least some of these changes appear to be a consequence of exposure to SARS-CoV-2 S1 and N antigens.

Molecular and serological survey of bovine viral diarrhea virus infection in cattle in Kazakhstan.

The aim of this study was to estimate the occurrence of bovine viral diarrhea virus (BVDV) infection and to assess the population immunity in cattle vaccinated against BVDV in different regions of Kazakhstan. Cattle samples were collected in 12 oblasts (43 districts) of Kazakhstan. A total of 2477 cattle from 114 herds and 21 Bukhara deer (Cervus elaphus bactrianus) were examined by ELISA and conventional RT-PCR. Univariate and multivariate logistic regression analysis was performed to identify risk factors associated with BVDV infection in the country. In total, antibodies against BVDV were found in 79.3% (1965/2477) of all the animals and 92.1% (105/114) of all the herds examined. Seroprevalence in unvaccinated and vaccinated animals was 48.6% (447/920) and 98.7% (1391/1410), respectively. Seroprevalence in deer was 19.1% (4/21). The BVDV RNA was detected in six unvaccinated cattle (0.2%). Sequence analysis of the 5'-untranslated region demonstrated that four of the detected strains belonged to BVDV-1 and two strains to BVDV-2. Regression analysis revealed that age, production type, housing method, farm size, and geographic location were risk factors for BVDV infection in cattle in Kazakhstan. The present data confirm circulation of BVDV-1 and BVDV-2 in Kazakhstan and highlight the need to improve strategies for prevention and control of BVDV infection in the country.