Epidemiology and transmission of hepatitis B and C viruses in Kazakhstan

Core components of infection prevention and control programs at the facility level in Kazakhstan: key challenges and opportunities

BACKGROUND

Kazakhstan is developing a National Roadmap to strengthen its Infection Prevention and Control (IPC), but until recently has lacked a country-wide facility-level assessment of IPC performance gaps.

METHODS

In 2021, the World Health Organization (WHO)'s IPC Core Components and Minimal Requirements were assessed at 78 randomly selected hospitals across 17 administrative regions using adapted WHO tools. The study included site assessments, followed by structured interviews with 320 hospital staff, validation observations of IPC practices, and document reviews.

RESULTS

All hospitals had at least one dedicated IPC staff member, 76% had IPC staff with any formal IPC training; 95% established an IPC committee and 54% had an annual IPC workplan; 92% had any IPC guidelines; 55% conducted any IPC monitoring in the past 12 months and shared the results with facility staff, but only 9% used monitoring data for improvements; 93% had access to a microbiological laboratory for HAI surveillance, but HAI surveillance with standardized definitions and systematic data collection was conducted in only one hospital. Adequate bed spacing of at least 1 m in all wards was maintained in 35% of hospitals; soap and paper towels were available at the hand hygiene stations in 62% and 38% of hospitals, respectively.

CONCLUSIONS

Existing IPC programs, infrastructure, IPC staffing, workload and supplies present within hospitals in Kazakhstan allow for implementation of effective IPC. Development and dissemination of IPC guidelines based on the recommended WHO IPC core components, improved IPC training system, and implementation of systematic monitoring of IPC practices will be important first steps towards implementing targeted IPC improvement plans in facilities.

Antibodies to Hepatitis B core antigen prevalence study in Kazakhstan

Introduction

Kazakhstan is being considered medium‐endemic for Hepatitis B virus infection (HBV). HBV remains transmissible by direct exposure to infected blood or organic fluids. This cross‐sectional study aimed to evaluate the prevalence of anti‐HBcore and the risk factors impacting positive anti‐HBcore markers among donors at Scientific‐Production Center of Transfusiology, Ministry of Healthcare of the Republic of Kazakhstan.

Materials and Methods

The samples taken from blood donors were tested for anti‐HBcore, by the chemiluminescence immunoassay method on the Architect i2000SR (Abbott). In case of positive anti‐HBcore, the blood samples were further tested for anti‐HBs on the Architect i2000SR (Abbott). Alanine aminotransferase (ALT) indicators were tested by kinetic method on the Biosystems A25 analyzer. Statistical analysis was conducted using R software (version 4.1.1, 2021).

Results

Five thousand seven hundred and nine people aged 18–66 years included in the study, the proportion of men and women was 68.17% and 31.83%, respectively. The average age of the participants was 35.7 ± 10.57 years. The prevalence of anti‐HBcore among donors was 17.2% (983). Among participants with elevated ALT (170), this marker was determined in 23%, and for donors with normal levels of ALT (5539)−17%. Participants with positive anti‐HBcore scores were on average older (41.8 vs. 34.4 years, p < .001) and Kazakhs (88.7% vs. 83.0%, p < .001) by nationality than study participants with negative results of anti‐HBcore.

Conclusions

Anti‐HBcore prevalence in Kazakhstan (17.2%) compared with other countries (Croatia 7%, France 7%, Germany 9%, Iran 16%, Malaysia 20%, respectively) remains above average. Given the prevalence of HBV and risk factors, it is recommended to include an additional anti‐HBcore marker in the mandatory screening of donated blood in the Kazakhstan Republic and improve preventive measures to prevent HBV transmission by blood transfusions.

Seroprevalence and risk factors for hepatitis B and hepatitis C in three large regions of Kazakhstan

Background & aims

Kazakhstan has implemented comprehensive programs to reduce the incidence of Hepatitis B and Hepatitis C. This study aims to assess seroprevalence and risk factors for HBsAg and anti-HCV positivity in three large regions of Kazakhstan.

Methods

A cross-sectional study was conducted in three regions geographically remote from each other. Participants were randomly selected using a two-stage stratified cluster sampling and were surveyed by a questionnaire based on the WHO STEP survey instrument. Blood samples were collected for HBsAg and anti-HCV testing.

Results

A total of 4,620 participants were enrolled. The seroprevalence was 5.5% (95%CI: 3.6%-8.4%) for HBsAg and 5.1% (95%CI: 3.5%-7.5%) for anti-HCV antibodies. Both were more prevalent in the western and northern regions than in the southern. A history of blood transfusion was significantly associated with anti-HCV presence, with odds ratios (ORs) of 2.10 (95%CI: 1.37–3.21) and was borderline associated with HBsAg 1.39 (95%CI: 0.92–2.10), respectively. Having a family member with viral hepatitis was also borderline associated (2.09 (95%CI: 0.97–4.50)) with anti-HCV positivity.

Conclusions

This study found a high-intermediate level of endemicity for HBsAg and a high level of endemicity for anti-HCV antibodies in three large regions of Kazakhstan. We found that history of surgery was not associated with HbsAg neither with anti-HCV seropositivity rates. Blood transfusion was associated with anti-HCV seropositivity, however, to investigate effectiveness of the introduced comprehensive preventive measures in health care settings, there is a need to conduct further epidemiological studies.

Prevalence of HIV, HCV and HBV in Central Asia and the Caucasus: A systematic review

BACKGROUND

Human immunodeficiency virus (HIV), hepatitis C virus (HCV) and hepatitis B virus (HBV) are substantial public health threats in the region of Central Asia and the Caucasus, where the prevalence of these infections is currently rising.

METHODS

A systematic review of MEDLINE, Embase and PsycINFO was conducted with no publication date or language restrictions through October 2019. Additional data were also harvested from national surveillance reports, references found in discovered sources, and other "grey" literature. It included studies conducted on high-risk populations (people who inject drugs (PWID), female sex workers (FSW), men who have sex with men (MSM), prisoners, and migrants) in Central Asia: Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan, and Uzbekistan; and the Caucasus: Armenia, Azerbaijan, Georgia, and Northern Caucasus region of the Russian Federation.

RESULTS

Wide ranges were noted for HIV prevalence: PWID 0-30.1%, MSM 0-25.1%, prisoners 0-22.8%, FSW 0-10.0%, and migrants 0.06-1.5%, with the highest prevalence of these high-risk groups reported in Kazakhstan (for PWID), Georgia (for MSM and prisoners) and Uzbekistan (for migrants). HCV prevalence also had a wide range: PWID 0.3-92.1%, MSM 0-18.9%, prisoners 23.8-49.7%, FSW 3.3-17.8%, and migrants 0.5-26.5%, with the highest prevalence reported in Georgia (92.1%), Kyrgyzstan (49.7%), and migrants from Tajikistan and Uzbekistan (26.5%). Similarly, HBV prevalence had a wide range: PWID 2.8-79.7%, MSM 0-22.2%, prisoners 2.7-6.2%, FSW 18.4% (one study), and migrants 0.3-15.7%.

CONCLUSION

In Central Asia and the Caucasus, prevalence of HIV, HCV and HBV remains exceedingly high among selected populations, notably PWID and MSM.

The epidemiology of hepatitis C virus in Central Asia: Systematic review, meta-analyses, and meta-regression analyses

The objective was to delineate hepatitis C virus (HCV) epidemiology in countries of Central Asia (CA), specifically Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan, and Uzbekistan. A systematic review was conducted guided by the Cochrane Collaboration Handbook, and reported using PRISMA guidelines. Meta-analyses were performed using DerSimonian-Laird random-effects models with inverse variance weighting. Random-effects meta-regression analyses were performed on general population studies. The systematic review identified a total of 208 HCV prevalence measures. No incidence or Turkmenistan studies were identified. Meta-analyses estimated HCV prevalence among the general population at 0.7% (95%CI: 0.7-0.8%) in Kazakhstan, 2.0% (95%CI: 1.7-2.4%) in Kyrgyzstan, 2.6% (95%CI: 1.7-3.6%) in Tajikistan, and 9.6 (95%CI: 5.8-14.2%) in Uzbekistan. Across CA, the pooled mean prevalence was 13.5% (95%CI: 10.9-16.4%) among non-specific clinical populations, 31.6% (95%CI: 25.8-37.7%) among populations with liver-related conditions, and 51.3% (95%CI: 46.9-55.6%) among people who inject drugs. Genotypes 1 (52.6%) and 3 (38.0%) were most frequent. Evidence was found for statistically-significant differences in prevalence by country, but not for a temporal decline in prevalence. CA is one of the most affected regions by HCV infection with Uzbekistan enduring one of the highest prevalence levels worldwide. Ongoing HCV transmission seems to be driven by injecting drug use and healthcare exposures.

Underreported injection drug use and its potential contribution to reported increase in sexual transmission of HIV in Kazakhstan and Kyrgyzstan

Background

We conducted a cross-sectional integrated bio-behavioral survey among sex partners of persons who inject drugs (PWID) to explore reasons for reported increase in reporting of heterosexually transmitted HIV in Kazakhstan and Kyrgyzstan.

Methods

Sexual partners of PWID were recruited through PWID. Behavioral data were collected through semi-structured interviews. Dried blood spots were obtained and tested for HIV and hepatitis C virus antibodies (HCVAb). Descriptive univariate and bivariate analyses, and multivariate analyses using logistic regression modeling were performed to identify factors associated with HIV and HCV infections.

Results

Among 1982 sex partners of PWID, overall HIV prevalence was 6.4%; 5.1% and 12.9% among those reported never and ever injecting drugs, respectively (p < 0.001). Overall, HCVAb prevalence was 21.3%; 15.0% and 53.9% among those reported never and ever injecting drugs, respectively (p < 0.001). Of HCV-positive participants, 58% and 34% (p < 0.001) reported prior history of injecting drug use among men and women, respectively. HIV prevalence was lower among HCV-negative (4.2%) compared to HCV-positive participants (14.4%) (p < 0.001). HIV prevalence was 3.5% (95%CI = 2.4–4.6) in a subset of female participants with no reported prior injecting drug use history and who were HCVAb-negative and did not report having an HIV-positive sex partner. Participant sex and number of sex partners as well as use of condoms in the past 12 months were not associated with HIV seropositivity.

Conclusions

High prevalence of HCV among sex partners of PWID who denied ever injecting drugs suggests underreporting of injecting practices. The increased attribution of HIV infection to sexual transmission based on self-report may be partly explained by underreporting of injection drug use due to stigmatization of this behavior.

Seroepidemiology of Hepatitis Viruses and Hepatitis B Genotypes of Female Marriage Immigrants in Korea

PURPOSE

The Korean society has moved rapidly toward becoming a multicultural society. This study aimed to estimate the seroprevalence of hepatitis viruses and investigate hepatitis B virus (HBV) genotypic diversity in female marriage immigrants.

MATERIALS AND METHODS

Screening program was conducted at support centers for multicultural families in 21 administrative districts in Korea between July 2011 and January 2017. A total of 963 female marriage immigrants were included in this study. Blood samples were tested for hepatitis viral markers and HBV genotype.

RESULTS

Subjects' median age was 33 years (20-40 years), and they originated from nine countries including Vietnam (n=422, 43.8%), China (n=311, 32.3%), the Philippines (n=85, 8.8%), Cambodia (n=58, 6.0%), and Japan (n=39, 4.0%). About 30% (n=288) of subjects required hepatitis A vaccination. HBsAg positive rate was 5.4% (n=52). Positive HBsAg results were the highest in subjects from Southeast Asia (6.6%, n=38). Anti-HBs positive rate was 60.4% (n=582). About 34% (n=329) of subjects who were negative for anti-HBs and HBsAg required HBV vaccinations. Genotypes B and C were found in 54.6% (n=12) and 45.4% (n=10) of the 22 subjects with HBV, in whom genotypes were tested. Eight (0.8%) subjects were positive for anti-HCV. Positive anti-HCV results were the highest in subjects from Central Asia (7.9%, n=3).

CONCLUSION

Testing for hepatitis viral marker (hepatitis A virus IgG and HBsAg/anti-HBs) is needed for female marriage immigrants. Especially, HBV genotype B is different from genotype C of Koreans. Therefore, interest and attention to vaccination programs for female marriage immigrants are necessary for both clinicians and public health institutes.

Historical epidemiology of hepatitis C virus in select countries-volume 4

Due to the introduction of newer, more efficacious treatment options, there is a pressing need for policy makers and public health officials to develop or adapt national hepatitis C virus (HCV) control strategies to the changing epidemiological landscape. To do so, detailed, country-specific data are needed to characterize the burden of chronic HCV infection. In this study of 17 countries, a literature review of published and unpublished data on HCV prevalence, viraemia, genotype, age and gender distribution, liver transplants and diagnosis and treatment rates was conducted, and inputs were validated by expert consensus in each country. Viraemic prevalence in this study ranged from 0.2% in Hong Kong to 2.4% in Taiwan, while the largest viraemic populations were in Nigeria (2 597 000 cases) and Taiwan (569 000 cases). Diagnosis, treatment and liver transplant rates varied widely across the countries included in this analysis, as did the availability of reliable data. Addressing data gaps will be critical for the development of future strategies to manage and minimize the disease burden of hepatitis C.

Seroprevalence of hepatitis B, hepatitis C, human immunodeficiency virus, Treponema pallidum, and co-infections among blood donors in Kyrgyzstan: a retrospective analysis (2013-2015)

Background

Post-Soviet Kyrgyzstan has experienced a major surge in blood-borne infections, but data from adequately powered, up-to-date studies are lacking. We thus examined a) the seroprevalences of hepatitis B virus surface antigen (HBsAg), HIV-1 p24 antigen and antibodies against hepatitis C virus (anti-HCV), human immunodeficiency viruses (anti-HIV-1/2, HIV-1 group O), and Treponema pallidum among blood donors in Kyrgyzstan and assess their distribution according to sex, age, and provinces of residence; b) trends in the respective seroprevalences; and c) co-infection rates among the pathogens studied.

Methods

Serological screening was performed on 37 165 blood donors at the Republican Blood Centre in Bishkek, Kyrgyzstan, between January 2013 and December 2015. We applied poststratification weights to control for sampling bias and used logistic regression analyses to examine the association of seropositivity and co-infections with sex, age, provinces of residence, and year of blood donation.

Results

Twenty nine thousand and one hundred forty-five (78%) donors were males and 8 020 (22%) were females. The median age was 27 years (range: 18 – 64). The prevalences of HBsAg, anti-HCV, HIV (p24 Ag and anti-HIV), and anti-T. pallidum were 3.6% (95%CI: 3.4 – 3.8%), 3.1% (3.0 – 3.3%), 0.78% (0.69 – 0.87%), and 3.3% (3.1 – 3.5%), respectively. Males were more likely to be seropositive for HBsAg than females (OR: 1.63; 95%CI: 1.40 – 1.90), but less likely to be seropositive for anti-HCV (0.85; 0.74 – 0.98) and HIV (0.65; 0.49 – 0.85). Prevalences were lower in the capital than in the other provinces. There was a decreasing trend in the seroprevalences of HBsAg, anti-HCV, and anti-T. pallidum from 2012 to 2015 (P-value for trend, P = 0.01, P < 0.0001, P < 0.0001, respectively), while the seroprevalence of HIV increased (P = 0.049). One hundred eighty donors (0.48%) were seropositive for multiple infections. The highest co-infection rate was observed between anti-T. pallidum and HBsAg (6.0%), followed by anti-HCV and anti-T. pallidum (5.2%), and HIV and anti-HCV (4.9%).

Conclusions

The data suggest that Kyrgyzstan can be reclassified from high to lower-intermediate HBsAg endemicity, whereas the high HIV prevalence with a rising trend is an alarming finding that needs to be urgently addressed by public health authorities. The observed co-infections suggest common risk factors but also common preventive interventions.

Electronic supplementary material

The online version of this article (doi:10.1186/s40249-017-0255-9) contains supplementary material, which is available to authorized users.

Hepatitis B virus burden in developing countries

Hepatitis B virus (HBV) infection has shown an intermediate or high endemicity level in low-income countries over the last five decades. In recent years, however, the incidence of acute hepatitis B and the prevalence of hepatitis B surface antigen chronic carriers have decreased in several countries because of the HBV universal vaccination programs started in the nineties. Some countries, however, are still unable to implement these programs, particularly in their hyperendemic rural areas. The diffusion of HBV infection is still wide in several low-income countries where the prevention, management and treatment of HBV infection are a heavy burden for the governments and healthcare authorities. Of note, the information on the HBV epidemiology is scanty in numerous eastern European and Latin-American countries. The studies on molecular epidemiology performed in some countries provide an important contribution for a more comprehensive knowledge of HBV epidemiology, and phylogenetic studies provide information on the impact of recent and older migratory flows.

Substantial decline in hepatitis B virus infections following vaccine introduction in Tajikistan

BACKGROUND

Tajikistan, considered highly endemic area for hepatitis B virus (HBV) in a pre-vaccine era, introduced hepatitis B vaccine in 2002 and reported ≥80% coverage with three doses of hepatitis B vaccine (HepB3) since 2004. However, the impact of vaccine introduction has not been assessed.

METHODS

We tested residual serum specimens from a 2010 national serosurvey for vaccine-preventable diseases in Tajikistan and assessed the prevalence of HBV infection across groups defined based on the birth cohorts' routine infant hepatitis B vaccination program implementation and HepB3 coverage achieved (≥80% versus <80%). Serosurvey participants were selected through stratified multi-stage cluster sampling among residents of all regions of Tajikistan aged 1-24 years. All specimens were tested for antibodies against HBV core antigen (anti-HBc) and those found positive were tested for HBV surface antigen (HBsAg). Seroprevalence and 95% confidence intervals were calculated and compared across subgroups using Satterthwaite-adjusted chi-square tests, accounting for the survey design and sampling weights.

RESULTS

A total of 2188 samples were tested. Prevalence of HBV infection markers was lowest among cohorts with ≥80% HepB3 coverage (ages, 1-6 years): 2.1% (95% confidence interval, 1.1-4.3%) for anti-HBc, 0.4% (0.1-1.3%) for HBsAg, followed by 7.2% (4.1-12.4%) for anti-HBc and 2.1% (0.7-6.1%) for HBsAg among cohorts with <80% HepB3 coverage (ages, 7-8 years), by 12.0% (8.7-16.3%) for anti-HBc and 3.5% (2.2-5.6%) for HBsAg among children's cohorts not targeted for vaccination (ages, 9-14 years), and 28.9% (24.5-33.8%) for anti-HBc and 6.8% (4.5-10.1%) for HBsAg among unvaccinated adult cohorts (ages, 15-24 years). Differences across groups were significant (p<0.001, chi-square) for both markers.

CONCLUSIONS

The present study demonstrates substantial impact of hepatitis B vaccine introduction on reducing HBV infections in Tajikistan. To achieve further progress in hepatitis B control, Tajikistan should maintain high routine coverage with hepatitis B vaccine, including birth dose.

Trends of Blood and Plasma Donations in Kazakhstan: 12-Years Retrospective Analysis

BACKGROUND

Each country faces a continuing challenge to collect enough blood to meet the national needs. According to WHO, there should be at least 20 blood donations per 1,000 population for developing countries, in Kazakhstan this indicator was only 16.8 in 2011. Thus, we conducted an epidemiological assessment and drew a map of the regional distribution of blood and plasma donations in Kazakhstan during the years 2000-2011.

METHODS

The retrospective study was conducted from 2000 to 2011. Data on blood and its components donations were acquired from the Ministry of Health (annual statistical reporting form N° 39).

RESULTS

During 2000-2011, number of blood donors decreased to 17.4% and blood donations to 6.3%. The proportion of non-remunerated blood donations and donors decreased from 97.6% to 77.9% and 97.9% to 87.7%, respectively. The paid donations had the opposite trend. Number of plasma donors increased in 2.1 times, plasma donations in 2.4 times, nevertheless the proportion of non-remunerated plasma donations decreased from 60.1% to 29.8%. The average number of blood donations per 1,000 population decreased from 19.8 (2000) to 16.8 (2011), plasma donations increased from 1.4 to 3.1. Regionally, annual average rates of blood and plasma donations per 1,000 population over 12 years varied greatly.

CONCLUSION

This is the first study conducted in Kazakhstan to provide detailed information, including the regional characteristics of blood and plasma donations over an extended period of time, which can be used in blood transfusion services work.

Associated factors for recommending HBV vaccination to children among Georgian health care workers

Background

Most cases of hepatitis B virus (HBV) infection and subsequent liver diseases can be prevented with universal newborn HBV vaccination. The attitudes of health care workers about HBV vaccination and their willingness to recommend vaccine have been shown to impact HBV vaccination coverage and the prevention of vertical transmission of HBV. The purpose of this study was to ascertain the factors associated with health care worker recommendations regarding newborn HBV vaccination.

Methods

A cross-sectional study of prevalence and awareness of hepatitis B and hepatitis B vaccine was conducted among randomly selected physicians and nurses employed in seven hospitals in Georgia in 2006 and 2007. Self-administered questionnaires included a module on recommendations for HBV, HCV and HIV.

Results

Of the 1328 participants included in this analysis, 36% reported recommending against hepatitis B vaccination for children, including 33% of paediatricians. Among the 70.6% who provided a reason for not recommending HBV vaccine, the most common concern was an adverse vaccine event. Unvaccinated physicians and nurses were more likely to recommend against HBV vaccine (40.4% vs 11.4%, PR 3.54; 95% CI: 2.38, 5.29). Additionally, health care worker age was inversely correlated with recommendations for HBV vaccine with older workers less likely to recommend it.

Conclusion

Vaccinating health care workers against HBV may provide a dual benefit by boosting occupational safety as well as strengthening universal coverage programs for newborns.