This post is by Global Center Director Christine Lubinski, reporting this week from CROI in San Francisco.
The evidence for scale-up of home-based testing is straightforward and compelling. In Africa, an estimated 17 million people with undiagnosed HIV infection are responsible for 90 percent of infections. Testing rates remain low in many sub-Saharan African countries, but home-based testing has proven to overcome many obstacles that keep people from finding out their HIV status in clinics.
Peter Cherutich, with the national AIDS program in Kenya, detailed the promise of home-based testing in a talk at this week’s CROI meeting in San Francisco entitled “HIV Prevention and Care through Door-to-Door HIV Testing and Counseling: Opportunities and Challenges.”
He began by reminding us all that testing is the foundation of HIV prevention and that knowledge of serostatus is effective in reducing risk behavior. A survey in Kenya found that HIV-infected persons who knew their status were 15 times less likely to engage in unsafe sex than those who do not.
And reticence to getting tested remains high. For example, a review of testing rates across a number of sub-Saharan African countries found the highest rates in South Africa, where 28.7 percent of women and almost 20 percent of men reported testing in the last year. This is in part because the model of voluntary counseling and testing is client-driven, requiring clients to self-identify as at risk. There are also challenges with health care facility-based testing, including the burden of transportation.
Home-based testing and counseling overcomes the obstacles of cost and transportation. It also encourages discussion within families and ensures that consent and confidentiality are protected.
There are basically two types of home-based testing and counseling (HBTC): door-to-door testing of the general population and targeted testing of household members of HIV-infected persons in care and treatment. Home-based testing is most effective and a wise use of resources in countries with high HIV prevalence, generalized epidemics, high density urban or rural areas, and sizeable populations on ART. Uganda, Kenya, Malawi, Zambia, Swaziland, and Lesotho all have robust HBTC programs. Uganda and Zambia have data showing that people are much more likely to be tested in a home context.
Home testing is done with a rapid diagnostic, with results given in the same visit. Couples counseling and referral to treatment services are part of these programs. In many cases, there is also a follow-up visit to ensure enrollment in HIV care. In Kenya, more than 85 percent of persons living with HIV in survey areas had previously undiagnosed HIV infection. Moreover, the average CD4 count of those identified was 411, showing that this strategy helps to identify people earlier in HIV infection. But Cherutich noted that linkage to care has been a challenge, with only 30 percent of those identified as positive in a Kenyan program actually presenting for care. At least one program in Malawi includes a component where community health workers actually immediately accompany the newly identified HIV-infected persons to a care and treatment program. This practice reduces the number of tests that can be done but helps ensure linkage to care and services.
In Uganda, 99 percent of the 2,300 family members approached through a home-based testing program accept testing. Thirty-seven percent of the adults were found to be infected, and 19 percent of children under five were found to have undiagnosed HIV infection. Home-based testing also provides a mechanism to identify pregnant women with HIV. The majority of those identified are women not engaged in antenatal care clinics, and this strategy can be a mechanism to connect them with needed HIV care.
The cost of this form of testing is variable but relatively modest. In Kenya, the cost is $5.88 for each person tested and $84 per positive case detected. In Uganda, the test costs $8 and $164 per HIV positive person detected.
There are operational challenges associated with HBTC program including finding people at home, especially young men. There are also a number of unanswered research questions. How often should HBTC be repeated in a given community? Does it make more sense to have this as a stand-alone service or in the context of a package of services? What level of population coverage necessary to make testing normative?
Cherutich called for national and international policies on HBTC guidelines, standard operating procedures, quality assurance standards, and confidentiality protocols. He noted the need for design studies to capture the cost of each averted infection to really assess the prevention implications of this testing intervention.
Home-based testing and counseling also has the strong potential to link people to male circumcision and other HIV prevention and treatment interventions.