New infections and HIV-1 subtypes among febrile persons and blood donors in Oyo State, Nigeria

HIV-1 residual risk and pre-treatment drug resistance among blood donors: A sentinel surveillance from Gabon

BACKGROUND

Surveillance of HIV-1 pre-treatment drug resistance (PDR) is essential for ensuring the success of first-line antiretroviral therapy (ART). Beside population-based surveys, sentinel surveillance of PDR and circulating HIV-1 clades in specific populations such as blood donors could efficiently inform decision-making on ART program. We therefore sought to ascertain HIV-1 residual infection, the threshold of PDR and viral diversity among recently-diagnosed blood donors in Gabon.

METHODS

A sentinel surveillance was conducted among 381 consenting blood donors at the National Blood Transfusion Center (NBTC) in Gabon from August 3,2020 to August, 31, 2021. In order to determine the residual risk of HIV transmission, viral load and HIV-1 Sanger-sequencing were performed at the Chantal BIYA International Reference Center (CIRCB)-Cameroon on HIV samples previously tested seronegative with ELISA in Gabon. Phylogeny was performed using MEGA X, PDR threshold>10% was considered high and data were analysed using p≤0.05 for statistical significance.

RESULTS

Five HIV-negative blood donors had a detectable viral load indicating a high residual risk of HIV transmission. Among the samples successfully sequenced, four participants had major drug resistance mutations (DRMs), giving a threshold of PDR of 25% (4/16). By drug class, major DRMs targeting NNRTI (K103N, E138G), NRTIs (L210W) and PI/r (M46L). The most representative viral clades were CRF02_AG and subtype A1. The genetic diversity of HIV-1 had no significant effect on the residual risk in blood transfusion (CRF02_AG, P = 0.3 and Recombinants, P = 0.5).

CONCLUSION

This sentinel surveillance indicates a high residual risk of HIV-1 transfusion in Gabon, thereby underscoring the need for optimal screening strategy for blood safety. Moreover, HIV-1 transmission goes with high-risk of PDR, suggesting suboptimal efficacy of ART. Nonetheless, the genetic diversity has limited (if any effect) on the residual risk of infection and PDR in blood donors.

Current Resistance of HIV-1 Strains Isolated in Volunteer Blood Donors in Gabon

Detection of drug resistance mutations (DRMs) and HIV-1 subtypes ensures effective therapeutic management for HIV-infected individuals. In Gabon, data on DRMs are very little available in the population of people living with HIV and also among voluntary HIV-positive blood donors. This study aimed to study subtypes and DRMs in HIV-1-positive volunteer blood donors in Gabon. A cross-sectional study was carried out at the National Blood Transfusion Center of Gabon. A purposive sampling method was used to collect 128 HIV-1 seropositive blood samples. Viral RNA was extracted on real-time PCR (Abbott 2000®), and sequencing was performed on ABI 3500 (Hitachi®). SPSS version 21.0 software was used for statistical analysis. Of the 128 seropositive volunteer donors included, men and the 29-39-age group were more representative at 78.9% and 49.2%, respectively. Eighty-two samples were sequenced. The majority strains identified were subtype A, subtype F, subtype G, CRF02_AG, and CRF45_cpx. The resistance mutations identified were K103N, L210W, E138G, V179D, V179T, and M46L. The prevalence of resistant subtypes was 25.6%. CRF02_AG strains exhibited high-level resistance to non-nucleoside reverse transcriptase inhibitors (NNRTIs), including efavirenz and nevirapine. The study identified major DRMs in reverse transcriptase and protease that confer high-level resistance to most NNRTIs, nucleoside reverse transcriptase inhibitors, and protease inhibitors. CRF02_AG was more predominant, and the frequency of resistant subtypes was high. However, these data will contribute to the therapeutic choice during the initiation of antiretroviral treatment in treatment-naive patients in Gabon.

Genetic diversity of the human immunodeficiency virus of type 1 in Gabonese transfusional settings

BACKGROUND

The high endemicity of transfusion-transmissible infections (TTIs) in sub-Saharan Africa is a real public health problem. To reduce the risk of HIV transmission through blood donation, the NBTC of Gabon has launched in recent years a reorganization of its blood transfusion system. This study aims to characterize the molecular strains of HIV-1 circulating in donors and to estimate the risk of viral transmission.

MATERIALS AND METHODS

A cross-sectional study was carried out during the period from August 2020 to August 2021 among 381 donors who had agreed to donate blood at the National Blood Transfusion Center (NBTC). Viral load was determined by Abbott Real-Time (Abbott m2000®, Abbott) and sequencing by the Sanger method (ABI 3500 Hitachi®). The phylogenetic tree was constructed by MEGA X software. Data were checked, entered, and analyzed using SPSS version 21.0 software, with p ≤ 0.05 considered statistically significant.

RESULTS

A total of 381 donors were enrolled in the study. Among the 359 seronegative donors, five (5) seronegative donors were detected positive for HIV-1 using Real-Time PCR. The residual risk was 648 per 1,000,000 donations. The prevalence of residual infection was 1.4% [0,01; 0,03]. Sixteen (16) samples were sequenced. The strains obtained were CRF02_AG (50%), subtype A1 (18.8%), subtype G (12.5%), CRF45_cpx (12.5%) and subtype F2 (6.2%). Six sequences clustered with A1, G, CRF02_AG, and CRF45_cpx subtypes.

CONCLUSION

The residual risk of HIV-1 transmission by blood transfusion remains a concern in the Gabonese transfusional settings. A policy based on improving the current screening strategy would involve the implementation of the nucleic acid test (NAT) in order to optimize the safety of the donation by detecting the HIV-1 subtypes in circulation in the donors.

Surveillance of Pretreatment Drug Resistance Among HIV-Infected Children in Ibadan, Nigeria

There are about 2.1 million children infected with HIV globally and about 120,000 deaths annually. Nigeria has one of the highest rates of pediatric HIV infection globally. Pretreatment HIV drug resistance data inform the choice of first- and second-line antiretroviral therapy (ART) regimens. This study investigated the prevalence of HIV drug-resistant strains among ART-naive children in Ibadan, Nigeria. A total of 20 children aged <15 years were enrolled. Demographic, clinical, and laboratory data were documented. Total nucleic acid was extracted from blood samples after which amplification of HIV-1 pol gene was done using polymerase chain reaction. Amplified gene was sequenced using big dye sequencing method. The sequenced HIV-1 pol gene was typed and analyzed for identification of mutations indicative of drug resistance across the different classes of ART. HIV-1 RNA pol gene was successfully amplified in 12/20 (60%) children. All were identified as HIV-1 and the subtypes were G and CRF 02AG, recombinant of 02_AG/G and recombinant of 02_AG/A1. Drug-resistant mutations (DRMs) were identified in 4/12 (33%). Three out of the four mutations were identified as non-nucleoside reverse transcriptase inhibitors DRM (K103N), whereas the fourth had nucleoside reverse transcriptase inhibitors DRM (M184V). Results from this preliminary study show that drug resistance among ART-naive children is a problem in Ibadan. Pretreatment drug resistance testing is desirable in children before initiation of ART to guide effective treatment.