TY - JOUR
T1 - Molecular epidemiology of the HIV-1 subtype B sub-epidemic in Bulgaria
AU - Alexiev, Ivailo
AU - Campbell, Ellsworth M.
AU - Knyazev, Sergey
AU - Pan, Yi
AU - Grigorova, Lyubomira
AU - Dimitrova, Reneta
AU - Partsuneva, Aleksandra
AU - Gancheva, Anna
AU - Kostadinova, Asya
AU - Seguin-Devaux, Carole
AU - Switzer, William M.
N1 - Funding Information:
This work was supported in part by a grant from the Ministry of Education and Science, Bulgaria (contract: DN03/16.12.2016). Use of trade names is for identification only and does not imply endorsement by the U.S. Department of Health and Human Services, the Public Health Service, or the Centers for Disease Control and Prevention (CDC). The findings and conclusions in this report are those of the authors and do not necessarily represent the views of the CDC, or any of the authors? affiliated institutions.
Funding Information:
Funding: This work was supported in part by a grant from the Ministry of Education and Science, Bulgaria (contract: DN03/16.12.2016).
Publisher Copyright:
© 2020 by the authors.
PY - 2020/4
Y1 - 2020/4
N2 - HIV-1 subtype B is the predominant strain in Bulgaria, yet little is known about the molecular epidemiology of these infections, including its origin and transmissibility. We used a phylodynamics approach by combining and analyzing 663 HIV-1 polymerase (pol) sequences collected from persons diagnosed with HIV/AIDS between 1988-2018 and associated epidemiologic data to better understand this sub-epidemic in Bulgaria. Using network analyses at a 1.5% genetic distance threshold (d) we found several large phylogenetic clusters composed mostly of men who have sex with men (MSM) and male heterosexuals (HET). However, at d = 0.5%, used to identify more recent transmission, the largest clusters dissociated to become smaller in size. The majority of female HET and persons with other transmission risks were singletons or pairs in the network. Phylogenetic analysis of the Bulgarian pol sequences with publicly available global sequences showed that subtype B was likely introduced into Bulgaria from multiple countries, including Israel and several European countries. Our findings indicate that subtype B was introduced into Bulgaria multiple times since 1988 and then infections rapidly spread among MSM and non-disclosed MSM. These high-risk behaviors continue to spread subtype B infection in Bulgaria as evidenced by the large clusters at d = 0.5%. Relatively low levels of antiretroviral drug resistance were observed in our study. Prevention strategies should continue to include increased testing and linkage to care and treatment, as well as expanded outreach to the MSM communities.
AB - HIV-1 subtype B is the predominant strain in Bulgaria, yet little is known about the molecular epidemiology of these infections, including its origin and transmissibility. We used a phylodynamics approach by combining and analyzing 663 HIV-1 polymerase (pol) sequences collected from persons diagnosed with HIV/AIDS between 1988-2018 and associated epidemiologic data to better understand this sub-epidemic in Bulgaria. Using network analyses at a 1.5% genetic distance threshold (d) we found several large phylogenetic clusters composed mostly of men who have sex with men (MSM) and male heterosexuals (HET). However, at d = 0.5%, used to identify more recent transmission, the largest clusters dissociated to become smaller in size. The majority of female HET and persons with other transmission risks were singletons or pairs in the network. Phylogenetic analysis of the Bulgarian pol sequences with publicly available global sequences showed that subtype B was likely introduced into Bulgaria from multiple countries, including Israel and several European countries. Our findings indicate that subtype B was introduced into Bulgaria multiple times since 1988 and then infections rapidly spread among MSM and non-disclosed MSM. These high-risk behaviors continue to spread subtype B infection in Bulgaria as evidenced by the large clusters at d = 0.5%. Relatively low levels of antiretroviral drug resistance were observed in our study. Prevention strategies should continue to include increased testing and linkage to care and treatment, as well as expanded outreach to the MSM communities.
KW - Drug resistance
KW - HIV-1
KW - Molecular epidemiology
KW - Prevention
KW - Subtype
KW - Transmission clusters
UR - http://www.scopus.com/inward/record.url?scp=85083307231&partnerID=8YFLogxK
U2 - 10.3390/v12040441
DO - 10.3390/v12040441
M3 - Article
C2 - 32295123
AN - SCOPUS:85083307231
SN - 1999-4915
VL - 12
JO - Viruses
JF - Viruses
IS - 4
M1 - 441
ER -