The Changing Epidemiology of Viral Hepatitis in a Post-Soviet Country-The Case of Kyrgyzstan.

Historically, viral hepatitis has been a considerable public health problem in Central Asian countries, which may have worsened after the dissolution of the Soviet Union. However, up-to-date seroepidemiological studies are lacking. The aim of the present study was, therefore, to provide current estimates of the seroprevalence of viral hepatitis in Kyrgyzstan, one of the economically least developed countries in the region. We conducted a population-based cross-sectional study in 2018 in the capital of Kyrgyzstan, Bishkek (n = 1075). Participants, children and adults, were recruited from an outpatient clinic. The data were collected during face-to-face interviews. A blood sample (6 mL) was collected from each participant and tested with ELISA for the presence of serological markers for five viral hepatitides (A, B, C, D, and E). Post-stratification weighing was performed to obtain nationally representative findings. The overwhelming majority of the study participants were positive for anti-HAV (estimated seroprevalence, 75.3%; 95% confidence interval, 72.5-77.9%). The weighted seroprevalence estimates of HBsAg, anti-HCV, and anti-HDV were 2.2% (1.5-3.3%), 3.8% (2.8-5.1%), and 0.40% (0.15-1.01%), respectively. Anti-HEV seropositivity was 3.3% (2.4-4.5%). Of the 33 HBsAg-positive participants, five (15%) were anti-HDV-positive. Our study confirms that Kyrgyzstan remains a highly endemic country for hepatitis virus A and C infections. However, seroprevalences of HBV and HDV were lower than previously reported, and based on these data, the country could potentially be reclassified from high to (lower) intermediate endemicity. The observed anti-HEV seroprevalence resembles the low endemicity pattern characteristic of high-income countries.

SARS-CoV-2 herd immunity of the Kyrgyz population in 2021.

In the fight against coronavirus infection, control of the immune response is of decisive importance, an important component of which is the seroprevalence of antibodies to SARS-CoV-2. Immunity to SARS-CoV-2 is formed either naturally or artificially through vaccination. The purpose of this study was to assess the seroprevalence of antibodies to SARS-CoV-2 in the population of Kyrgyzstan. A cross-sectional randomized study of seroprevalence was carried out according to a program developed by Rospotrebnadzor and the St. Petersburg Pasteur Institute, taking into account WHO recommendations. The ethics committees of the Association of Preventive Medicine (Kyrgyzstan) and the St. Petersburg Pasteur Institute (Russia) approved the study. Volunteers (9471) were recruited, representing 0.15% (95% CI 0.14-0.15) of the total population, randomized by age and region. Plasma antibodies (Abs) to the nucleocapsid antigen (Nag) were determined. In vaccinated individuals, Abs to the SARS-CoV-2 receptor-binding domain antigen (RBDag) were determined. Differences were considered statistically significant at p < 0.05. The SARS-CoV-2 Nag Ab seroprevalence was 48.7% (95% CI 47.7-49.7), with a maximum in the 60-69 age group [59.2% (95% CI 56.6-61.7)] and a minimum in group 1-17 years old [32.7% (95 CI: 29.4-36.1)]. The highest proportion of seropositive individuals was in the Naryn region [53.3% (95% CI 49.8-56.8)]. The lowest share was in Osh City [38.1% (95% CI 32.6-43.9)]. The maximum SARS-CoV-2 Nag seropositivity was found in the health-care sector [57.1% (95% CI 55.4-58.8)]; the minimum was seen among artists [38.6% (95% CI 26.0-52.4)]. Asymptomatic SARS-CoV-2 Nag seropositivity was 77.1% (95% CI 75.6-78.5). Vaccination with Sputnik V or Sinopharm produced comparable Ab seroprevalence. SARS-CoV-2 Nag seropositivity in the Kyrgyz population was 48.75% (95% CI 47.7-49.7), with the mass vaccination campaign undoubtedly benefitting the overall situation.

Costs of diarrheal disease and the cost-effectiveness of a rotavirus vaccination program in kyrgyzstan.

INTRODUCTION: We examined the cost-effectiveness of a rotavirus immunization program in Kyrgyzstan, a country eligible for vaccine funding from the GAVI Alliance. METHODS: We estimated the burden of rotavirus disease and its economic consequences by using national and international data. A cost-effectiveness analysis was conducted from government and societal perspectives, along with a range of 1-way sensitivity analyses. RESULTS: Rotavirus-related hospitalizations and outpatient visits cost US$580,864 annually, of which $421,658 (73%) is direct medical costs and $159,206 (27%) is nonmedical and indirect costs. With 95% coverage, vaccination could prevent 75% of rotavirus-related hospitalizations and deaths and 56% of outpatient visits and could avert $386,193 (66%) in total costs annually. The medical break-even price at which averted direct medical costs equal vaccination costs is $0.65/dose; the societal break-even price is $1.14/dose for a 2-dose regimen. At the current GAVI Alliance-subsidized vaccine price of $0.60/course, rotavirus vaccination is cost-saving for the government. Vaccination is cost-effective at a vaccine price $9.41/dose, according to the cost-effectiveness standard set by the 2002 World Health Report. CONCLUSIONS: Addition of rotavirus vaccines to childhood immunization in Kyrgyzstan could substantially reduce disease burden and associated costs. Vaccination would be cost-effective from the national perspective at a vaccine price $9.41 per dose.