战略与国际研究中心-The-World-s-Largest-HIV-Epidemic-in-Crisis_-HIV-in-South-Africa_70页_4mb

Summary of the HIV Incidence Provincial Surveillance System (HIPSS) Report (June 2018)

Core Content

The HIV Incidence Provincial Surveillance System (HIPSS) is a longitudinal study conducted in KwaZulu-Natal, South Africa, aimed at monitoring HIV prevalence and incidence trends in a "real-world non-trial" setting. The study was designed to assess the impact of HIV-related prevention, treatment, and care programs on key indicators such as HIV prevalence, ART uptake, CD4 cell counts, and viral suppression. It also examined sociodemographic and behavioral factors associated with HIV infection and provided insights into the transmission dynamics and prevention strategies in the region.

Main Purpose and Objectives

Purpose

To establish a population-based surveillance platform in KwaZulu-Natal for monitoring HIV and related health outcomes.

Objectives

• Determine the impact of HIV prevention and treatment programs on HIV prevalence, ART uptake, CD4 cell counts, and viral suppression.
• Analyze sociodemographic and behavioral characteristics of individuals and households in relation to HIV infection.
• Investigate sexual networks and transmission dynamics to guide targeted prevention efforts.

Key Methodology

• Study Duration: June 11, 2014, to June 22, 2015.
• Study Areas: Rural (Vulindlela) and peri-urban/urban (Greater Edendale) in the uMgungundlovu district of KZN.
• Sampling Method: Multistage cluster sampling was used to select enumeration areas (EA), households, and participants.
• Data Collection:
  • Household questionnaires captured socio-demographic, economic, and health service access data.
  • Individual questionnaires gathered information on risk behaviors, prevention program exposure, and linkage to care.
  • Biological samples (blood, urine, and self-collected swabs) were collected for laboratory testing.
• Data Analysis: Population-weighted data were analyzed using SAS survey procedures, adjusting for non-response.

Key Findings

Household and Individual Demographics

• Total Enrolled: 11,289 households and 9,812 individuals (86.9% response rate).
• Gender Distribution: 63.9% females, 36.1% males.
• Median Age: Females 27.4 years (IQR 20.6–36.2), Males 26.4 years (IQR 20.1–35.0).
• Socioeconomic Status:
  • 57.9% of participants had HSV-2 antibodies.
  • 2.8% had syphilis antibodies.
  • 2.8% had gonorrhoea, 7.1% had chlamydia, and 9.0% had trichomoniasis.
  • Pregnancy prevalence: 7.1% among females aged 15–35.
  • VMMC coverage: 31.9% among males.

HIV Prevalence

• Overall Weighted Prevalence: 36.3% (95% CI 34.8–37.8).
• By Gender:
  • Females: 44.1% (95% CI 42.3–45.9).
  • Males: 28.0% (95% CI 25.9–30.1).
• By Age Group:
  • 15–19 years: 5.0% (Females) vs 11.5% (Males).
  • 20–24 years: 10.1% (Females) vs 32.4% (Males).
  • 35–39 years (Females): 66.4% (95% CI 61.7–71.2).
  • 40–44 years (Males): 59.6% (95% CI 53.0–66.3).

HIV-Related Indicators

• Knowledge of HIV Status: 65% of females vs 52% of males.
• ART Coverage: 70% of females vs 69% of males.
• Viral Suppression (viral load <1000 copies/ml): 90% of females vs 86% of males.
• Median Viral Load: Males had higher median viral load (4940 copies/ml) than females (67 copies/ml).
• Median CD4 Cell Count: Males had lower median CD4 count (402 cells/μl) than females (540 cells/μl).

Transmission Dynamics

• HIV-1 Genotyping: 90 heterosexual clusters were analyzed, with 123 females phylogenetically linked to 103 males.
• Age Disparity in Partnerships: Young women (<25 years) were more likely to partner with older men (mean age difference 8.7 years), while women aged 25–40 had partnerships with men of similar age (mean difference 1.1 years).
• Viral Load >50,000 copies/ml: 11.0% of females and 24.0% of males had high viral load, regardless of ART use.

Key Insights and Implications

• High HIV Prevalence: KZN has the highest HIV prevalence globally, with over 36% of the population living with HIV.
• Gender Disparities: Women have significantly higher HIV prevalence than men, especially in younger age groups.
• Progress Toward 90-90-90 Targets:
  • 65% of females and 52% of males knew their HIV status.
  • 70% of females and 69% of males were on long-term ART.
  • 90% of females and 86% of males were virally suppressed.
• Need for Targeted Interventions: Age-disparate sexual partnerships between young women and older men are key drivers of HIV transmission. Programs must address these dynamics to effectively reduce new infections.
• Call for Scale-Up: Despite progress, less than 50% of the target population are reached by evidence-based interventions. A scale-up of prevention and treatment programs is essential to control the epidemic.

Contributors and Funding

• Principal Investigator: Ayesha BM Kharsany (CAPRISA)
• Project Director: Cherie Cawood (Epicentre)
• Project Manager: David Khanyile (Epicentre)
• Epidemiologist: Annette Gerritsen (Epicentre), Adrian Puren (NICD), Mary Glenshaw (CDC), Kaymarlin Govender (HEARD), Gavin George (HEARD), Sean Beckett (HEARD)
• Statistician: Lara Lewis (CAPRISA), Anneke Grobler (CAPRISA)
• Technical Advisors: Kassahun Ayalew, Karidia Diallo (CDC)
• Funding: PEPFAR through CDC, under the cooperative agreement 3U2GGH000372-02W1.

Conclusion

The HIPSS study highlights the significant burden of HIV in KwaZulu-Natal, with high prevalence, particularly among women, and persistent challenges in achieving the UNAIDS 90-90-90 targets. It underscores the importance of targeted prevention and treatment strategies, especially those addressing age-disparate partnerships, improved access to ART, and viral suppression. The study calls for an exponential scale-up of interventions to reduce new infections and ultimately control the HIV epidemic in the region.