5.1. Infants and children

Mortality is very high in the first year of life among infants infected with HIV who go untreated. In this period early HIV testing, prompt return of results and rapid initiation of treatment are vital. HIV testing for infants should be implemented with the aim of identifying as many HIV-infected infants as possible as early as possible. See the glossary and Chapter 7 (particularly section 7.1.4) for details on terminology and testing strategies, including for infants.

For infants and children under 18 months, HIV infection can be diagnosed only by virological testing; maternal HIV antibodies remain in the infant's bloodstream until 18 months of age, making test results from serological assays ambiguous. Virological testing using nucleic acid testing (NAT) technologies can be conducted using dried blood spot (DBS) specimens, which are collected at local sites and sent to centralized laboratories for testing. While early testing is increasing, there are ongoing challenges of access, such as prompt return of test results and initiation of early ART among infants who test HIV-positive.

Several approaches can increase infant testing. Scaling up early infant diagnosis (EID) through task sharing with lay providers is one promising approach (78). Development, now underway, of virological assays for use at the point of care is expected to greatly improve access to early diagnosis and treatment. HIV testing at the time of birth may improve linkage to treatment and reduce loss to follow-up; however, it is likely be an effective public health strategy only in settings with a high proportion of deliveries taking place in facilities. In any case, this approach would miss infant infections that take place during breastfeeding.

For children 18 months of age and older (who were not breastfed or who have stopped breastfeeding at least six weeks earlier), standard HIV serological assays such as RDTs and EIAs can reliably determine HIV status. A negative serological test result for an infant does not completely exclude HIV exposure and infection, particularly when certain RDTs are used to test infants between four and 18 months of age, due to imperfect sensitivity during seroconversion for infection acquired postpartum through breastfeeding. During this time virological tests may be used to determine HIV infection.

5.2. Adolescents

In high prevalence settings there are two groups of adolescents (that is, people 10–19 years of age) who need access to HIV testing: (1) perinatally HIV-infected adolescents who were not diagnosed in infancy and (2) adolescents who acquire HIV through early sex or injecting drug use, particularly adolescents from key populations.

Perinatally infected adolescents urgently need to be diagnosed so that they can be linked to HIV care and start ART. In sub-Saharan Africa there are a significant number of undiagnosed adolescents who were infected perinatally or through transmission in health-care settings (for example, through transfusions or unsafe injections).

Particularly in high prevalence settings, adolescence may be a period of high risk of HIV infection. In such settings adolescent girls are generally at higher risk than males in their age group. In all regions adolescents from key population groups are at especially high risk for HIV infection (10).

Engaging adolescents in HIV testing, as well as in prevention, treatment and care, requires specific strategies. All HTS for adolescents, either in health services or in the community, should be based on adolescent-friendly principles to ensure that psychological as well as physical needs are addressed (54). Adolescents may need support particularly with issues of disclosure – when and to whom to disclose HIV-positive status (54) (see Chapter 3).

Involving adolescents in the design, delivery and evaluation of HIV services is necessary to ensure that these programmes address their needs (54). Services need to be convenient and available, through flexible opening hours and/or walk-in or same-day appointments. Separate hours and special events exclusively for adolescents may help overcome adolescents' concerns that older relatives, neighbours or family friends will see them attending HIV services, including HTS.

HTS for adolescents should be based on a human rights and public health approach (54). As with all HTS, HTS for adolescents should offer protection from stigma and discrimination related to HIV-positive status and risk behaviours and should also be confidential, respectful, inclusive and non-judgemental. It should provide strong referrals and linkages to HIV prevention, treatment, care and support services. When appropriate, and only with the adolescent's specific permission, health-care personnel should engage the support of adults – family members, teachers, community members – as adolescents learn to manage living with HIV.

Services for adolescents need to be tailored to different epidemiological contexts and different adolescent populations. For example, in high burden, priority countries, adolescent boys can be linked to VMMC and adolescent girls to reproductive health services. Special considerations are needed for adolescents from key populations and vulnerable adolescents, including those living on the streets, orphans, adolescents in child-headed households, girls engaged in sex with older men or in multiple or concurrent sexual partnerships and adolescents who are sexually exploited (10). In some settings specific campaigns and use of social media or web-based approaches, involving adolescents in identifying communication channels and appropriate language, may help reach adolescents, including those from key populations. In low-level or concentrated epidemic settings, however, adolescent-focused HTS for the general population usually are not prioritized due to the very low prevalence of HIV in adolescents.

Policies related to age of consent to testing can pose barriers to adolescents' access to HTS and other health services, particularly for adolescents from key populations (55). Age of consent for HTS varies from country to country. WHO recommends that children and adolescents themselves be involved in the testing decision as much as possible (55). Governments should revisit age of consent policies in light of adolescents' rights to make choices about their own health and well-being (with consideration for different levels of maturity and understanding). Authorities also should consider the role of surrogate decision-makers in HTS for adolescents without parents or for those unwilling to involve parents. In any case providers of HTS should be aware of laws and policies governing the age of consent and develop appropriate procedures based on this legal framework to ensure that children and adolescents have access to HTS.

5.3. Pregnant women

HTS as early as possible during pregnancy enables pregnant women with HIV to obtain and benefit most from prevention, treatment and care and to reduce the risk of HIV transmission to their infants. WHO recommends offering HTS to pregnant women through a PITC approach (126). Globally, this approach has been widely adopted and has proved acceptable to pregnant women. It is an essential component of all PMTCT programmes (21, 189).

Many countries prioritize PITC in ANC as a key component of their effort to eliminate mother-to-child transmission of HIV (eMTCT). HIV testing is also being effectively combined with screening for syphilis and hepatitis B, hepatitis B vaccination for infants and other testing.

PITC in ANC settings has considerable public health benefits. Still, measures must be taken to prevent unintentionally or intentionally coercive testing (21). These measures include regular mentoring and supervision of staff, retraining where necessary and monitoring of PITC procedures to ensure their acceptability to pregnant women.

HTS for pregnant women is an entry point into couples or partner HTS. In high prevalence settings WHO recommends couples and partner HIV testing for all pregnant women and their partners (16) (see section 5.4). Particularly for women from migrant or key populations, HIV testing may also be a point of entry to a broad range of pregnancy care services (190). In low prevalence settings WHO recommends couples and partner HIV testing for pregnant women from key populations and for the partners of women diagnosed with HIV (16).

The package of care for pregnant women with HIV should include systematic screening for TB symptoms and referral and treatment as necessary. The presence of undetected TB among HIV-positive pregnant women doubles the rate of vertical HIV transmission (191).

Pregnant women testing HIV-positive must be linked to ART for PMTCT and HIV services for their own health. WHO recommends Option B+, which involves initiation of ART as soon as possible, regardless of CD4 count, and continuation of treatment for life for the mother's infection (192).

5.4. Couples and partners

Participating in couples and partner HTS has a number of benefits. These include adoption of prevention strategies by the couple (for example, condom use, immediate ART, PrEP), safer conception, improved uptake of and adherence to practices for PMTCT as well as to one's own ART (thus reducing transmission risk as well as morbidity and mortality) (16). Partner testing is an efficient and effective way of identifying additional people with HIV, who also can benefit from treatment. Couples and partner HTS help more people know their HIV status, particularly men, who in generalized epidemic settings are substantially less likely to test than women. Couples and partner HTS for the partners of women attending ANC, in particular, is a focus in the 21 priority eMTCT countries¹ (194).

Couples and partner HTS can be conducted in various settings, including ANC and community-based TB services, through home-based HTS, during premarital health visits and in couples' HIVST (169, 195–197). People attending ART services can be encouraged to bring their partners to be tested. Couple and partner testing should also be a priority for people in key populations, including men who have sex with men. Programmes that particularly serve key populations should provide and encourage partner testing.

As with all HTS approaches, couples and partner HTS should be voluntary. Informed consent should be obtained from all individuals receiving HIV testing. Providers must be aware of the potential for intimate partner violence and should support people's decisions not to test with their partners.

Currently, the prevalence of serodiscordance is estimated at one-half to two-thirds of cohabitating couples or partners where one partner has HIV (198–201). Nonetheless, many people do not know their partner's HIV status. With the exception of a few countries such as Rwanda and Zambia, in most countries the proportion of couples and partners who test together is less than 20% (24). According to the WHO HIV Country Intelligence database, as of April 2014 only half (28/58) of WHO HIV focus countries made it a policy to offer ART to the HIV-positive partner in a serodiscordant couple, irrespective of CD4 count, as WHO recommends. A recent desk review of national policies in 21 priority countries found that most did not have specific targets or indicators to monitor their progress in couples and partner HTS or to measure its uptake or coverage.² In an associated online survey of field experts from these priority countries, less than half judged that most people would find couples and partner HTS acceptable, accessible or both.

In low-level and concentrated epidemics, couples and partner HTS should be made available for partners of people with HIV and people from key populations.

5.5. Men

In high prevalence settings fewer men than women report ever testing for HIV (24). As a consequence men are more likely to start ART at later stages of HIV infection and thus experience higher morbidity and mortality after starting ART (202, 203). There are a number of barriers to men's access to available HTS, including fear, stigma, the perception that health facilities are “female” spaces and both the direct costs and the opportunity costs of accessing services.

Despite these barriers current approaches to delivering HTS can reach men. Successful approaches include PITC in ANC and other clinical settings and home-based and mobile HTS (106, 204–206). As reported in section 4.3.2, on-site HTS at the workplace reaches men in formal employment (156–158). The availability of HTS services in VMMC clinics in the 14 VMMC priority countries has provided adolescent and adult males seeking circumcision with an opportunity to learn their HIV status. Those testing HIV-positive can be referred to prevention, treatment and care services. Although they will not have the benefit of HIV prevention from circumcision, they should not be denied circumcision if they want it nonetheless. Although these approaches do reach men, in many settings rates of men's use of available HTS remain low. This low uptake compromises the impact of proven HIV prevention interventions, including VMMC and treatment for prevention. Greater emphasis on reaching men is required in many high prevalence settings.

To increase men's uptake of ANC-based PITC, a letter to male partners of ANC clients can invite them to test at ANC (207, 208) or in a community-based setting (209). A trial in Malawi found that provider-initiated notification increased uptake of HTS among partners of those attending STI services, including male partners (204). A high proportion of these partners tested HIV-positive for the first time. This notification was undertaken with consent from the HIV-positive client who had attended STI services (87).

Men are less likely than women to use clinical health services. Therefore, community-based approaches to reaching men, including home-based and mobile HTS, may be helpful. Mobile HTS can reach many men (206). In high prevalence settings in sub-Saharan Africa, men were as likely as women to accept an offer of home-based HIV-testing, provided services were delivered when men were at home, for example, in the evenings or during weekends (210). Home-based HTS has also been shown to reach couples and partners (106).

Maximizing men's uptake of HTS requires a strategic combination of facility- and community-based approaches. As discussed in section 4.3, selecting a strategic combination of service delivery approaches for men requires considering men's preferences, local context, epidemiology and available resources. In addition, services should be delivered at times and in locations suitable to men who are not being reached by existing services. Support for HIVST may also increase men's uptake of HIV testing (165, 174).

5.6. Key populations

Key populations – men who have sex with men, people in prisons and other closed settings, people who inject drugs, sex workers and transgender people – continue to have limited access to health services, including HTS. In many settings these groups experience particularly high HIV incidence (10). In many high prevalence settings, however, the HIV response has focused largely on the general population and not adequately appreciated the role of key populations in the dynamics of the epidemic. Even in countries with concentrated epidemics, efforts to reach people from each key population group often remain inadequate.

For key populations, especially those whose behaviour is criminalized, HTS services are sometimes misused in punitive or coercive ways (26). As a result, people from key populations avoid health services that they need. Stigma, discrimination, lack of confidentiality, coercion and fear of repercussions, as well as lack of appropriate health services, resources and supplies, prevent people from testing and, if HIV-positive, linking to care (211, 212). Like all HTS, programmes for key populations need to emphasize WHO's “5 Cs” – particularly consent, confidentiality and connection to comprehensive prevention, treatment and care (see section 1.7).

Community-based HTS is a critical approach for reaching people from key populations who are unlikely to go to a facility for HIV testing, particularly those who are asymptomatic. To improve access to and uptake of HIV testing, community-based HTS should be made available in locations and settings acceptable and convenient to people from key populations (213). Also, HIVST may prove to be another important way to increase access to HIV testing among key populations and, hence, to prevention, treatment and care services (14, 172). PITC among key populations is recommended, so long as it is not compulsory or coercive and it is linked to treatment and care (10). In addition to HTS, testing and screening for STIs, TB and viral hepatitis should be offered to key populations (10). Intensified TB case finding, along with HTS, also is particularly beneficial among key populations. These populations are highly vulnerable to TB, particularly in countries with high burdens of both TB and HIV (214).

In prisons and other closed settings, offering voluntary HIV testing as part of a package of care is a critical approach (see box next page). HIV testing using RDTs could improve uptake of HTS and increase the speed with which clients receive test results and learn their HIV status. Particular attention should go to providing accurate information, obtaining informed consent and maintaining confidentiality. Also, there are often major challenges to continuity of care within closed settings and between prisons and the community (215); these need to be addressed.

Retesting at least annually is recommended for all people from key populations. More frequent voluntary retesting may be beneficial, depending on risk behaviours (see sections 3.3 and 7.4).

5.7. Other vulnerable populations

Depending on context, there are a number of other groups, in addition to key populations, that are particularly vulnerable to HIV infection. These include, in high prevalence settings, migrant workers, refugees and other displaced populations, and other country-specific populations that may be at increased risk, for example, fisherfolk and long-distance truck drivers, all of whom can be hard to reach and, typically, seldom use HIV services.

Migrant workers, refugees and people who are displaced have difficulty accessing health-care services because of stigma, language differences, lack of required documentation, lack of transportation and long distances to services, discrimination and legal barriers. Some jurisdictions mandate HIV testing of immigrants; this requirement is not justified and can exacerbate the challenges of providing voluntary health services, including voluntary HIV testing. Displacement of key populations and others through human trafficking may further complicate the provision of HTS (216).

To address the needs of vulnerable populations, countries need to evaluate their epidemic and its social context and identify the groups, in addition to key populations, that are at highest risk and in need of services. Based on these assessments, programmes can adapt HTS approaches and deploy them so as to increase access to testing and uptake. Special policies and practices to protect vulnerable populations from mandatory or compulsory testing may be needed.

Footnotes

1

Angola, Botswana, Burundi, Cameroon, Côte d'Ivoire, Democratic Republic of Congo, Ethiopia, Ghana, Kenya, Lesotho, Malawi, Mozambique, Namibia, Nigeria, Rwanda, South Africa, Swaziland, United Republic of Tanzania, Uganda, Zambia and Zimbabwe.

2

Unpublished review, Darbes L et al., 2015.