This case report outlines the circumstances surrounding one instance of MTCT which occurred in Kenya in 2022. Susan’s case provides an in-depth reporting of how MTCT is still happening, and what is needed to optimize care for WLWH and their HIV exposed infants. Late engagement in antenatal/HIV care, difficulty accepting and disclosing a new diagnosis of HIV, unrecognized non-adherence, fragmented care (e.g., giving birth at a separate facility than PMTCT clinic), and delays in HIV and viral load testing may have contributed to this case of MTCT. In contrast, sustained engagement in care, and intensive postpartum monitoring and support provided by a professional Lactation Specialist, PMTCT clinic providers, and eventually Susan’s partner may have been key to optimizing health and wellbeing for Susan and her son despite MTCT having occurred.

In 2022, more than half of new HIV infections among children occurred during pregnancy when mothers did not receive ART, stopped taking ART, or were newly infected with HIV [7]. Given Susan was more than halfway through her pregnancy when she presented for antenatal care and discovered she was living with HIV, it is possible that HIV transmission occurred during pregnancy. Women in sub-Saharan and East African countries commonly delay engagement in antenatal care which has been related to varied factors including lower maternal education, uncertainties about pregnancy status, low household income and increased birth order [20, 21]. In Kenya, approximately 82% of women deliver their babies in a health facility and 89% are attended to by a skilled provider, yet, only around 66% of women attend the recommended four or more antenatal care visits [22]. These statistics reflect Susan’s experience as this was her third pregnancy, and despite being a planned pregnancy, timely prenatal care was missing from her plan. HIV testing is a critical component of antenatal care in this setting, and in such high prevalence areas, regular testing, regardless of pregnancy status, should also be widely promoted. In Susan’s case, HIV testing prior to or earlier in her pregnancy could have led to more timely HIV treatment and a reduced risk for MTCT.

Detecting HIV is a first step to preventing further transmission. However, receiving a new diagnosis of HIV is a life altering event, and accepting the diagnosis, disclosing it to partners and family, and committing to lifelong treatment is emotionally and sometimes practically speaking, difficult. Denial and stigma often impede optimal adherence immediately after diagnosis. Indeed, several previous studies indicate that women newly diagnosed with HIV during pregnancy struggle with adherence and are less likely to remain engaged in care and sustain viral suppression [15, 23, 24]. Disclosing a new diagnosis of HIV can be extremely difficult, especially in cases where the partner’s status is unknown or HIV negative. Fears of stigma, being blamed, punished or being abandoned lead some women to withhold information about their HIV status from their partner and this directly impacts their medication adherence and engagement in care [13, 16, 25,26,27]. In Kenya, non-disclosure of HIV status to male partners has been associated with an increased risk for MTCT [28]. Unfortunately, despite frequent interactions with providers, Susan’s struggles to reveal her HIV diagnosis to her partner and adhere to ART were not recognized until the results of her viral load test came back at around nine weeks postpartum. During our first encounter with Susan, she reported perfect adherence to ART—despite later admitting to PMTCT clinic staff she had been throwing away her medications. Indeed, self-report can be an unreliable way to assess adherence [29]. Susan’s experience underscores the need for more intensive support for perinatal women newly diagnosed with HIV including support for disclosure to partners and more frequent objective monitoring of adherence/viral suppression through viral load testing. Other recent publications have also pointed to the need for increased viral load monitoring among pregnant and breastfeeding WLWH [30, 31].

This case of MTCT may have also occurred during labor and delivery. Kenya’s 2022 HIV prevention and treatment guidelines include ways to reduce the risk of HIV transmission during labor and birth such as minimizing vaginal examinations, using aseptic delivery techniques and avoiding artificial rupture of membranes [17]. Providers may consider these guidelines for WLWH, and HIV status is normally documented in the Mother and Child Health Handbook that mothers in Kenya typically bring to any hospital visit up to five years postpartum [32]. Yet, there is not always time for providers to review the handbook, and a lack of privacy in the maternity wards (where mothers often share beds) can leave women reluctant to discuss their HIV status with providers—this may have been the case for Susan. To complicate matters, Susan’s high viral load was yet to be discovered at the time of delivery, and neither infant PCR nor maternal viral load testing are routinely carried out at the time of birth in this setting [17]. Overall, it was not clear if any special considerations were made in managing Susan’s labor and delivery. However, improved communication with providers could have led to actions to reduce the chance of MTCT during labor and delivery.

Immediately after delivery, all women are encouraged to breastfeed their babies [18]. For WLWH, this should be after administering the first dose of HIV prophylaxis medication to their newborns [17]. Susan’s baby, who was seemingly healthy at birth, was exposed to HIV in breastmilk immediately postpartum without the protection of prophylaxis medications. In similar settings, infants who did not receive HIV prophylaxis medications were found to be at a higher risk of MTCT during breastfeeding [33, 34]. Thus, the failure to coordinate the provision of HIV prophylaxis medications to Susan’s son immediately after birth could have also been a factor in this case of MTCT.

Early testing and optimized treatment for infants exposed to HIV is part of the first pillar of the Global Alliance to end AIDS in Children. Indeed, the Lactation Specialist’s observations and communications with clinic providers which led to an early HIV test was an important factor for Susan’s son [4]. Yet, despite being tested at four weeks postpartum (compared to the routine testing at six weeks), it was not until Susan’s baby was about nine weeks old that she received the test results and her son was given ART. This type of delay in receiving and relaying test results is not uncommon. In fact, during this period, a shortage in laboratory reagents delayed infant PCR tests for most infants. HIV tests normally drawn at six weeks postpartum were not drawn until 8–10 weeks postpartum. Such a delay may have been detrimental to Susan’s son who could have benefited from testing and treatment even earlier. According to Kenya’s most recent HIV prevention and treatment guidelines (2022), infants at high risk of HIV acquisition (such as those born to WLWH whose viral load is unknown or who have been on ART for less than 12 weeks), should be considered for HIV testing immediately after birth. This guideline, which has yet to be fully implemented, would have been applicable in the case of Susan and her son. Moreover, the Lactation Specialist’s first referral to PMTCT clinic providers at just two weeks postpartum might have also prompted earlier testing and treatment given Susan’s diagnosis late in pregnancy and her baby’s symptoms. In addition to earlier HIV testing, using point of care testing with faster turnaround times has been shown to significantly reduce the time it takes to initiate ART for newly diagnosed infants [35].

HIV exposed infants have worse outcomes than infants born to women without the virus [36]. Therefore, optimal nutrition is of paramount importance for HIV exposed infants. However, women in this setting face many challenges adhering to infant feeding guidelines including food and financial insecurity, perceived breastmilk insufficiency and contrary cultural norms [18, 37,38,39,40]. Susan’s meetings with a Lactation Specialist early postpartum may have been an important factor not only through initiating early HIV testing but also by supporting Susan to sustain her exclusive breastfeeding practice. That Susan was able to maintain exclusive breastfeeding, was a protective factor for her son, as providing breastmilk only during the first six months is associated with reduced infant morbidity and mortality [41, 42].

This case sheds light on ways MTCT may still occur even when mothers are engaged in care. Yet, the rate of MTCT among women engaged in care is low, with one study in Kenya showing a transmission rate of just 2.5% among WLWH engaged in care at four Kenyan hospitals in 2016 [11]. Given most MTCT continues to occur among women not engaged in HIV care, more action is needed to understand and eliminate barriers to HIV testing and treatment for women and girls—particularly in sub-Saharan Africa where girls and young women 15–24 years old accounted for more than 77% of all new infections among this age group in 2022 [5, 7].