HIV infection

人类免疫缺乏病毒感染

Evidence-backed information EN 6/7 applicable sections · ZH 6/7 applicable sections Updated Oct 23, 2026

Human immunodeficiency virus (HIV) infection has been a global public health issue for more than 40 years and remains a focus of prevention, treatment, and cure research ^[1]^[2]. Preexposure prophylaxis (PrEP) and nonoccupational postexposure prophylaxis (nPEP) are effective biomedical interventions for reducing new infections among people at risk ^[1]. Although still stigmatized, HIV infection is now a chronic and manageable condition when viral suppression is achieved through antiretroviral therapy ^[2].

Read the full clinical and epidemiological profile 7

Definition

HIV is a retrovirus, with HIV-1 being the cause of the AIDS epidemic ^[2]. The virus invades host cells by attaching to CD4 receptors and subsequently to one of two major chemokine coreceptors, CCR5 or CXCR4, with the infected host cell—most often a T lymphocyte—being destroyed as the virus replicates ^[2]. If unchecked, infection leads to an immune-deficient state and, over a period of approximately 2–10 years, to AIDS ^[2].

Clinical features

Untreated HIV infection progressively depletes CD4-bearing lymphocytes, most often T lymphocytes, leading to an immune-deficient state ^[2]. The typical clinical course spans approximately 2–10 years from infection to severe immune compromise and demise when left untreated ^[2]. With the advent of rapid diagnostics and effective antiretroviral therapy, the natural history has been markedly altered, and HIV infection is now considered a chronic and manageable condition characterized by viral suppression and improved health outcomes ^[2].

Epidemiology

Human immunodeficiency virus (HIV) continues to show disparities in incidence across populations, with certain groups remaining at high risk for HIV infection ^[1]. These disparities in HIV incidence underscore the need for targeted prevention interventions such as preexposure prophylaxis (PrEP) and nonoccupational postexposure prophylaxis (nPEP) ^[1].

Transmission

HIV-1 is transmitted via body fluids and secretions ^[2]. Achieving viral suppression through antiretroviral therapy eliminates sexual transmission of the virus, a finding that has informed both individual treatment decisions and broader public health strategy ^[2].

Prevention

Preexposure prophylaxis (PrEP) and nonoccupational postexposure prophylaxis (nPEP) are evidence-based pharmacologic interventions for preventing new HIV infections, and clinical guidelines exist to direct their prescribing ^[1]. Efficient use of these interventions, combined with strategies that promote treatment retention among people at high risk, is central to reducing HIV incidence ^[1]. At the population level, achieving viral suppression in individuals living with HIV eliminates sexual transmission, making universal access to prevention, treatment, and long-term care the foundation of epidemic control ^[2].

Surveillance note

GlobalID source-data note: HIV surveillance populations differ by source: Brazil separates adult and child series, the United States NHSS series covers persons aged 13 years and older, Taiwan's source label includes vertical-transmission and pregnancy-related reporting, and some countries publish AIDS separately. Use the original source label and population scope; these rows are not interchangeable all-age totals.

References

1 Yingling C et al. Pharmacoprevention of Human Immunodeficiency Virus Infection. Nurs Clin North Am. 2020 Sep. PMID: 32762861. doi: 10.1016/j.cnur.2020.06.006. PubMed: https://pubmed.ncbi.nlm.nih.gov/32762861/
2 Bekker LG et al. HIV infection. Nat Rev Dis Primers. 2023 Aug 17. PMID: 37591865. doi: 10.1038/s41572-023-00452-3. PubMed: https://pubmed.ncbi.nlm.nih.gov/37591865/