HIV-1 genetic diversity and drug resistance mutations in the northern Brazilian region

ABSTRACT Brazil is a huge continental country with striking geographic differences which are well illustrated in the HIV/AIDS epidemic. Contrasting with the significant decline in the national AIDS detection rate in the last decade, a linear growth has been reported in the Northern region. Despite its public health and epidemiologic importance, there is scarce HIV-1 molecular data from Northern Brazil. This scoping review summarizes recent epidemiologic data with special emphasis on HIV-1 genetic diversity and antiretroviral drug resistance mutations in patients from the seven Northern states of Brazil. Studies from the Northern Brazil on different HIV-1 genomic regions, mostly pol (protease/reverse transcriptase) sequences of naïve/antiretroviral treated adults/children were retrieved from PubMed/MEDLINE electronic database. These studies indicate a consistent molecular profile largely dominated by HIV-1 subtype B with minor contribution of subtypes F1 and C and infrequent detection of other subtypes (A1, D, K), recombinants (BF1, BC), circulating recombinant forms (CRF) as the new CRF90_BF1 and CRF02_AG-like, CRF28-29_BF-like, CRF31_BC-like, and a potential new CRF_BF1. This pattern indicates a founder effect of subtype B and the introduction of non-B-subtypes and recombinants probably generated in the Southern/Southeastern regions. In naïve populations transmitted drug resistance (TDR) can impact the outcome of first-line antiretroviral treatment and prophylactic/preventive regimens. In the Northern region TDR rates are moderate while patients failing highly active antiretroviral therapy (HAART) showed high prevalence of acquired drug resistance mutations. The limited HIV-1 molecular data from Northern Brazil reflects the great challenges to generate comprehensive scientific data in isolated, underprivileged areas. It also highlights the need to invest in local capacity building which supported by adequate infrastructure and funding can promote robust research activities to help reduce the scientific asymmetries in the Northern region. Currently the impacts of the overwhelming COVID-19 pandemic on the expanding HIV/AIDS epidemic in Northern Brazil deserves to be closely monitored.

An overview of the molecular and epidemiological features of HIV-1 infection in two major cities of Bahia state, Brazil

BACKGROUND The high mutation rate of the human immunodeficiency virus (HIV) has created a public health challenge because the use of antiretroviral drugs can generate selective pressure that drives resistance in these viruses. OBJECTIVE The aim of this work was to characterise the molecular and epidemiological profile of HIV in Bahia, Brazil. METHODS DNA sequences from regions of HIV gag, pol, and env genes were obtained from previous studies performed in this area between 2002 and 2012. Their genotype and drug-resistance mutations were identified using bioinformatics tools. Clinical and epidemiological data were analysed. FINDINGS Among 263 individuals (46.4% male), 97.5% were asymptomatic and 49.1% were receiving treatment. Most of the individuals were 31 to 40 years old (36.9%) and infected through heterosexual contact (40.7%). The predominant genotype was B (68.1%) followed by BF recombinants (18.6%). Among the individuals infected with either F or BF genotypes, 68.4% were women and 76.8% were infected through heterosexual transmission. The prevalence of associated mutations conferring antiretroviral resistance was 14.2%, with 3.8% of all mutations conferring resistance to protease inhibitors, 9.43% to nucleoside reverse transcriptase inhibitors, and 8.5% to non-nucleoside reverse transcriptase inhibitors. Drug resistance was higher in individuals receiving treatment (26.1%) than in the drug-naïve (4.3%) individuals. MAIN CONCLUSIONS This study will contribute to the understanding and monitoring of HIV epidemic in this Brazilian region.

High prevalence and incidence of HIV-1 in a counseling and testing center in the city of Itajaí, Brazil

ABSTRACT Itajaí is a port city in southern Brazil with one of the highest incidence and mortality rates from AIDS in the country. The prevalence and incidence of HIV infection were investigated in 1085 of 3196 new HIV-1 infection cases evaluated in the counseling and testing center of Itajaí from January 2002 to August 2008. Recent infections were assessed using the BED(tm), and polregion sequencing was performed in 76 samples. The prevalence ranged from 3.08% to 6.17% among women and from 10.26% to 17.36% among men. A total of 17% of infections were classified as recent, with annual incidence varying from 1.6% to 4.8 per 100 patient/year among women and from 2.05% to 8.5 per 100 patient/year among men. Pol sequences were obtained from 38 randomly recent infections selected individuals: 71% were infected by subtype C, 24% B, 2% D, and 2% F1. Among 38 subjects with established infection, 76% were subtype C, and 24% B. Transmitted drug resistance was detected in 18.4% of recent infection subjects (7.8% to nucleoside analog reverse-transcriptase inhibitors, 5.2% to non-nucleoside reverse-transcriptase inhibitors, and 5.2% protease inhibitors) and 5.2% of subjects with established infection had nucleoside analog reverse-transcriptase inhibitors resistance. The high prevalence and incidence of HIV infection in this region is unprecedented in studies involving cases evaluated in the counseling and testing centers in Brazil.

Primary resistance of HIV to antiretrovirals among individuals recently diagnosed at voluntary counselling and testing centres in the metropolitan region of Recife, Pernambuco

Determining the prevalence and type of antiretroviral (ARV) resistance among ARV-naïve individuals is important to assess the potential responses of these individuals to first-line regimens. The prevalence of primary resistance and the occurrence of recent infections among individuals with human immunodeficiency virus (HIV)/acquired immune deficiency syndrome (AIDS) were identified among recently diagnosed patients at five sexually transmitted disease/AIDS testing and counselling centres in the metropolitan region of Recife (RMR), Pernambuco, Brazil, between 2007-2009. One-hundred and eight samples were analysed using the Calypte® BED assay. Males predominated (56%), as did patients aged 31-50 years. Twenty-three percent presented evidence of a recent HIV infection. The median CD4+ T lymphocyte count was 408 cells/mm³ and the median viral load was 3.683 copies/mL. The prevalence of primary resistance was 4.6% (confidence interval 95% = 1-8.2%) based on criteria that excluded common polymorphisms in accordance with the surveillance drug resistance mutation criteria. The prevalence of resistance to non-nucleoside reverse transcriptase, nucleoside/nucleotide reverse transcriptase and protease inhibitors were 3.8%, 1.5% and 0.8%, respectively. Fifty-seven percent of strains were from clade B, 37.7% were clade F and 3.1% were clade C; there were no statistically significant differences with respect to resistance between clades. Recent infection tended to be more common in men (p = 0.06) and in municipalities in the south of the RMR (Jaboatão dos Guararapes and Cabo de Santo Agostinho) (p = 0.046). The high prevalence of recent infection and the high prevalence of non-B strains in this poor Brazilian region merit further attention.

Sequencing of gag gene for classification of HIV subtype from the patients living in the Northern area of Vietnam

Using nested PCR with the specific primers for gag gene and the sequencing data from blood samples of HIV patients, we demonstrated that subtype E is also very common in the Northern area of Vietnam. This method can be applied for the cloning of HIV genes and molecular epidemiology of HIV-l in Vietnam.