High-Level Drug-Resistant Mutations among HIV-1 Subtype A6 and CRF02_AG in Kazakhstan

HIV incidence in Kazakhstan increased by 73% between 2010 and 2020, with an estimated 35,000 people living with HIV (PLHIV) in 2020. The development of antiretroviral drug resistance is a major threat to effective antiretroviral therapy (ART), yet studies on the prevalence of drug resistance in Kazakhstan are sparse. In this study on the molecular epidemiology of HIV in Kazakhstan, we analyzed 968 partial HIV-1 pol sequences that were collected between 2017 and 2020 from PLHIV across all regions of Kazakhstan, covering almost 3% of PLHIV in 2020. Sequences predominantly represented subtypes A6 (57%) and CRF02_AG (41%), with 32% of sequences exhibiting high-level drug resistance. We further identified distinct drug-resistant mutations (DRMs) in the two subtypes: subtype A6 showed a propensity for DRMs A62V, G190S, K101E, and D67N, while CRF02_AG showed a propensity for K103N and V179E. Codon usage analysis revealed that different mutational pathways for the two subtypes may explain the difference in G190S and V179E frequencies. Phylogenetic analysis highlighted differences in the timing and geographic spread of both subtypes within the country, with A62V-harboring subtype A6 sequences clustering on the phylogeny, indicative of sustained transmission of the mutation. Our findings suggest an HIV epidemic characterized by high levels of drug resistance and differential DRM frequencies between subtypes. This emphasizes the importance of drug resistance monitoring within Kazakhstan, together with DRM and subtype screening at diagnosis, to tailor drug regimens and provide effective, virally suppressive ART.

Antiretroviral therapy resistance mutations among HIV infected people in Kazakhstan

In Kazakhstan, the number of people living with HIV (PLHIV) has increased steadily by 39% since 2010. Development of antiretroviral therapy (ART) resistance mutations (ARTRM) is a major hurdle in achieving effective treatment and prevention against HIV. Using HIV pol sequences from 602 PLHIV from Kazakhstan, we analyzed ARTRMs for their association with factors that may promote development of ARTRMs. 56% PLHIV were infected with HIV subtype A6 and 42% with CRF02_AG. The ARTRM Q174K was associated with increased viral load and decreased CD4+ cell count, while infection with CRF02_AG was associated with a lower likelihood of Q174K. Interestingly, CRF02_AG was positively associated with the ARTRM L10V that, in turn, was observed frequently with darunavir administration. Infection with CRF02_AG was positively associated with the ARTRM S162A that, in turn, was frequently observed with the administration of nevirapine, also associated with lower CD4 counts. Zidovudine or Nevirapine receipt was associated with the development of the ARTRM E138A, that, in turn, was associated with lower CD4 counts. Determination of a patient's HIV variant can help guide ART choice in Kazakhstan. For example, PLHIV infected with CRF02_AG will benefit less from darunavir and nevirapine, and emtricitabine should replace zidovudine.

Hepatitis B, Hepatitis C, tuberculosis and sexually-transmitted infections among HIV positive patients in Kazakhstan

In contrast with global trends, HIV prevalence in Kazakhstan and other Central Asian countries has been rising in recent years. In this study, we analyzed hepatitis B (HBV), hepatitis C (HCV), tuberculosis (TB) and sexually-transmitted (STI) co-infections among 500 HIV positive study participants recruited from all regions of Kazakhstan. Among our study participants, 27%, 8%, 2%, and 5% were coinfected with, respectively, HCV, TB, HBV, and STI. A considerable proportion of the study participants was also found with triple or quadruple infections of HCV/TB (12%), TB/STI (0.8%), HCV/STI (2%), HCV/HBV (1%), HBV/TB (0.4%), HBV/STI (0.2%), HBV/HCV/TB (0.4%), HBV/HCV/STI (0.2%), or HCV/TB/STI (0.2%). Strong associations were found of certain age groups, duration of HIV infection, and practices of injection drug use and sexual contact with PLWH, with co-infections of HIV/HCV and HIV/TB. The odds of having death was 4.07 times higher with TB/HIV as compared to other co-infections. Co-occurrence of HIV with HCV, HBV, and TB infections among participants of this study highlights the necessity of regular screening for HCV infection among HIV infected patients, together with implementation of vigilant vaccination protocols against HBV and TB. Additionally, persons who inject drugs especially need to be focused for harm reduction efforts that include opiate substitution therapy, needle or syringe exchange programs, regular screening, and increased availability of ART and direct acting antivirals.

Implementation of antiretroviral therapy (ART) in former Soviet Union countries

Against the current global trends, in the former Soviet Union (FSU) countries HIV prevalence is on the rise. Visa-free movement across borders has facilitated migrant-associated HIV transmission within this region. Despite efforts from the governments to curtail the growing epidemic, there is still a serious need for the development of strategies that focus on high-risk behaviors and practices responsible for the continued transmission of HIV in this region. While governments of FSU countries have taken commendable steps in recent years to address hurdles at each step of the HIV care continuum, to ensure 100% antiretroviral treatment (ART) accessibility to people living with HIV (PLHIV), testing for HIV needs to be enforced widely in FSU countries. Stigma against people who inject drugs (PWID), men who have sex with men (MSM), migrants, and PLHIV need to be addressed. Finally, to avoid breaks in ART supply, FSU countries need to gain independence in funding HIV care so that the provision of ART to PLHIV is made available without interruption.

Short communication: molecular epidemiology of HIV type 1 infection in Kazakhstan: CRF02_AG prevalence is increasing in the southeastern provinces

To analyze HIV-1 genetic variants in Kazakhstan, HIV-1 sequences were obtained from 205 antiretroviral-treated (ART) and naive patients in 2009-2013. Samples were collected in the most populous cities and provinces of Kazakhstan. On the basis of phylogenetic analyses of partial pol sequences, subtype A variant intravenous drug user (IDU)-A (which is dominant in the former Soviet Union) was found in 60.0% of the individuals, followed by CRF02_AG (34.6%); the rest of the samples were subtype B, CRF03_AB, CRF63_02A1, and CRF07_BC. The proportion of CRF02_AG has increased significantly since 2001-2003, when it was less than 5%. The majority of the CRF02_AG cases were found in Almaty, the former capital and the most populous city in Kazakhstan. The IDU-A variant dominated in the industrial regions of northern and central Kazakhstan and some other regions. Both dominant HIV-1 genetic variants were almost equally represented in the two main transmission groups: IDUs and heterosexuals. The analysis of drug-resistant mutations found a low prevalence of drug resistance in 165 therapy-naive individuals (3.0%). Thus, in the beginning of the second decade of the 2000s, the HIV epidemic in Kazakhstan is driven by two main genetic variants: IDU-A and CRF02_AG.