High uptake of home-based HIV testing in Zambia, but repeat visits needed to get close to universal coverage

Preliminary results from PopART, a large-scale study of a universal test and treat approach to slowing the spread of HIV in southern Africa, show that a door-to-door HIV testing programme is feasible, acceptable and effective. Testing was most likely to be accepted by women, younger people, those with symptoms and those who had not recently tested. Following repeat visits to households, knowledge of HIV status increased from around 50% of residents to around 90%.

Kwame Shanaube and colleagues report results in the current issue of AIDS.

PopART, also known as HPTN 071, is a large community-randomised trial being carried out in high-prevalence communities in Zambia and South Africa. The study is comparing the impact on HIV incidence of household-based HIV testing and linkage to care by community health workers, and immediate initiation of antiretroviral treatment delivered through routine health care services, to the standard of care.

Glossary

adjusted odds ratio (AOR)

Comparing one group with another, expresses differences in the odds of something happening. An odds ratio above 1 means something is more likely to happen in the group of interest; an odds ratio below 1 means it is less likely to happen. Similar to ‘relative risk’. 

consent

A patient’s agreement to take a test or a treatment. In medical ethics, an adult who has mental capacity always has the right to refuse. 

retention in care

A patient’s regular and ongoing engagement with medical care at a health care facility. 

90-90-90 target

A target set by the Joint United Nations Programme on HIV/AIDS (UNAIDS) for 90% of people with HIV to be diagnosed, 90% of diagnosed people to be taking treatment, and 90% of people on treatment to have an undetectable viral load. 

test and treat

A public health strategy in which widespread HIV testing is facilitated and immediate treatment for those diagnosed with HIV is encouraged.

PopART is an important test of the feasibility of offering testing and treatment at a very large scale, essential for achievement of the 90-90-90 target of 90% of people with HIV diagnosed, 90% of diagnosed people on treatment and 90% of those on treatment virally suppressed.

Although the uptake of HIV testing in Zambia has increased dramatically in recent years, people do not test often enough  only 46% of women and 37% of men report having tested in the previous year. Modelling studies suggest that a universal test and treat approach will only be effective if very high levels of uptake of HIV testing and immediate treatment are achieved and sustained.

Researchers therefore examined data on the uptake of HIV testing during the first 18 months of trial implementation, paying particular attention to factors associated with acceptance of testing. The analysis only looks at the four urban and peri-urban Zambian communities receiving the ‘full’ PopART intervention.

This involves community health workers (lay counsellors) systematically visiting all households within a geographical area and offering the PopART intervention. All household members are offered home-based HIV testing and counselling. Individuals found to be HIV-positive are referred to government health clinics for immediate HIV treatment, regardless of CD4 cell count. Support is also offered for adherence, retention in care, HIV prevention, STI screening, TB screening, and male circumcision.

The community health workers return to households throughout the year as necessary to follow up on referrals and linkages to care, and to offer HIV testing to household members who were absent at previous visits or who had declined testing.

During the first 18 months, 48,583 households were visited, with basic details of 121,130 adult household members being recorded.

Of the 59,283 adult men, 14% could not be contacted, 8% did not give consent to be included in PopART, 21% declined HIV testing and 4% said they had previously been diagnosed with HIV. This left 30,226 men who accepted HIV testing.

Of the 61,847 adult women, 4% could not be contacted, 5% did not give consent to be included in PopART, 22% declined HIV testing and 9% said they had previously been diagnosed with HIV. This left 36,668 women who accepted HIV testing.

Of those who accepted the offer of testing, 5.7% of men and 9.3% of women were newly diagnosed with HIV.

Of those who consented to take part in PopART, acceptance rates were similar between men (71%) and women (73%). However, it was much harder for the community health workers to contact men, due to employment that takes men away from home, beer drinking outside the home and other social factors. Repeat visits to households, weekend visits and community-based campaigns targeting men were used in order to reach more men. Just under half of the men who tested (47%) did so on a repeat visit to the household.

The most important factor associated with uptake of HIV testing was TB symptoms: men with symptoms were more than four times more likely to test than those without (adjusted odds ratio 4.55), while women were three times more likely to test (AOR 3.03). There was a similar relationship with symptoms of sexually transmitted infections (AOR for men 3.33, for women 3.45). Those with symptoms appear to have accurately judged themselves as having risk factors for HIV infection – for example, 21% of men with STI symptoms and 41% of women with TB symptoms who tested did indeed have HIV.

People who had never previously tested or who had last tested more than a year ago were more likely to accept HIV testing. Acceptance rates were low in those who had tested in the last few months.

Uptake was higher in younger age groups, steadily decreasing as people got older. For example, for men, with 18-19 year olds treated as the comparison group (AOR 1.0), the odds of taking a test were lower in 20-24 year olds (AOR 0.86), 30-39 year olds (AOR 0.54) and those over the age of 50 (AOR 0.34).

These data come from four communities, and acceptance rates varied considerably between the communities. The researchers suggest that two of the communities had greater previous exposure to HIV testing interventions from different organisations, perhaps making people more receptive to the PopART intervention. One of the communities had more residents engaged in formal employment, making them more difficult to find at home.

Before the intervention, 41% of men and 55% of women had reasonably accurate knowledge of their HIV status (i.e. they had tested negative in the previous year or had previously tested positive). Following the intervention, knowledge of status increased to 88% of men and 92% of women.

“The current study provides important insight into the feasibility of delivering the first ‘90’ of the UNAIDS 90–90–90 targets under ‘real life’ conditions in SSA [sub-Saharan Africa],” Kwame Shanaube and colleagues conclude. “The uptake of testing can be increased to 72.2%, but challenges still remain in finding men and a one-off intervention is unlikely to be successful but will require repeated visits and multiple strategies.”

References

Shanaube K et al. What works – reaching universal HIV testing: lessons from HPTN 071 (PopART) trial in Zambia. AIDS 31: 1555-1564, 2017. (Full text freely available).