Pre-treatment drug resistance among patients initiating antiretroviral therapy (ART) in Zimbabwe: 2008-2010.
BACKGROUND
Zimbabwe set up 12 sentinel sites to monitor HIV drug resistance (HIVDR) following the international standards for prevention of HIVDR from 2008 to 2010.


METHODS
Participants were consecutively enrolled. Blood was collected and used for CD4 count, viral load (VL) and pre-treatment DR (PDR) tests besides routine baseline tests. We analyzed the characteristics of participants enrolled into the survey and estimated the point prevalence of PDR and its associated factors among ART initiators in a cross-sectional analysis using the baseline data collected from a prospective cohort in 12 purposefully selected sentinel sites.


RESULTS
A total of 1728 participants (96 % response rate) were enrolled and 1610 had complete data. Of the 1610 there were more females (68.7 %) than males (31.3 %). The median CD4 count was 168 cells/mm(3) with males having lower values (P = 0.003). Ninety-six percent of participants had a VL ≥ 1000 copies/ml and the median VL was 128,000. Previous exposure to antiretroviral drugs (ARVs) was mainly through PMTCT (5 % of the participants). Overall, PDR mutations were detected in 6.3 % (95 % CI 5.2-7.7) of the 1480 successfully genotyped participants. However, the prevalence of PDR mutations was double for those with previous exposure (12.1 %) to ARVs compared with those without previous exposure (5.7 %, P = 0.002).


CONCLUSIONS
The results show a moderate level of PDR prevalence among ART initiators. To maintain the efficacy of the current first-line regimens, there is need to strengthen all HIVDR prevention efforts and to conduct further studies to investigate optimal strategies that can prolong the efficacy of first-line ARV regimens in the country.
Ministry of Health and Child Care, Harare, Zimbabwe. mungatim@yahoo.com.|Department of Community Medicine, University of Zimbabwe, Harare, Zimbabwe. mungatim@yahoo.com.
More
M
Mungati
Ministry of Health and Child Care, Harare, Zimbabwe.
Mutsa
M
Mhangara
Centers for Disease Control and Prevention, Harare, Zimbabwe.
Elizabeth
E
Gonese
Ministry of Health and Child Care, Harare, Zimbabwe.
Owen
O
Mugurungi
Ministry of Health and Child Care, Harare, Zimbabwe.
Janet
J
Dzangare
National Microbiology Reference Laboratory (NMRL), Harare, Zimbabwe.
Stella
S
Ngwende
National Microbiology Reference Laboratory (NMRL), Harare, Zimbabwe.
Patience
P
Musasa
Newlands Clinic, Harare, Zimbabwe.
Maureen
M
Wellington
Department of Community Medicine, University of Zimbabwe, Harare, Zimbabwe.
Gerald
G
Shambira
Ministry of Health and Child Care, Harare, Zimbabwe.
Tsitsilina
T
Apollo
Center for Disease Control and Prevention, Atlanta, GA, USA.
Chunfu
C
Yang
Center for Disease Control and Prevention, Atlanta, GA, USA.
Joshua
J
DeVos
Center for Disease Control and Prevention, Atlanta, GA, USA.
Jennifer
J
Sabatier
Centers for Disease Control and Prevention, Harare, Zimbabwe.
Peter
P
Kilmarx
World Health Organization, Harare, Zimbabwe.
Christine
C
Chakanyuka-Musanhu
Department of Community Medicine, University of Zimbabwe, Harare, Zimbabwe.
Mufuta
M
Tshimanga
D000328:Adult; D044966:Anti-Retroviral Agents / Q000627:therapeutic use*; D023241:Antiretroviral Therapy, Highly Active; D018791:CD4 Lymphocyte Count; D003430:Cross-Sectional Studies; D024882:Drug Resistance, Viral; D005260:Female; D005838:Genotype; D015658:HIV Infections / Q000188:drug therapy* / Q000453:epidemiology / Q000821:virology; D015497:HIV-1 / Q000187:drug effects* / Q000235:genetics / Q000502:physiology; D006306:Health Surveys / Q000379:methods / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D008875:Middle Aged; D009154:Mutation; D017063:Outcome Assessment, Health Care / Q000379:methods / Q000706:statistics & numerical data; D015995:Prevalence; D011446:Prospective Studies; D019562:Viral Load / Q000187:drug effects; D015030:Zimbabwe / Q000453:epidemiology
D044966:Anti-Retroviral Agents
Genotyping; HIVDR; PDR; Prevalence; Surveillance