Discussion
HIV transmission
Our analysis provided insight into the barriers and facilitators of extended infant PNP. The PROMISE-EPI mothers interviewed were intentionally those whose infants were at higher risk of HIV acquisition through breastfeeding due to unsuppressed maternal plasma viral load. Understanding their challenges and preferences is essential to better inform the national program and scale up promising practices. The data from the HCP and PROMISE-EPI interviews were congruent with those from the mothers, while providing a broader view.The mothers, as well as the health care professionals, were critical of the national program’s PNP. Main barriers were due to the AZT/3TC formulation. The process of dissolving the AZT/3TC tablet has been described as time consuming, which was particularly challenging in case of non-disclosure and/or fear of stigma. In addition, the complex preparation of AZT/3TC tablets may have contributed to inadequate dosing. Manipulation and calculation errors may occur with pediatric formulations, particularly with small volume administration and pre-dilution (The AZT/3TC bitter taste, sometimes associated with regurgitation had a negative impact on child cooperation. Poor palatability had already been largely reported as an obstacle to successful administration of pediatric drugs (We found that time consuming, complex preparation and poor palatability of the AZT/3TC tablets had a negative impact on the drug acceptability, which likely had resulted in poor adherence. In comparison, the single drug and the ready-to-use lamivudine oral solution were considered to facilitate good adherence. The provision of a syringe, accompanied by instructions and practice of how to draw the medicine, was appreciated by the mothers. This facilitated the ease of administration of the drug, even when the child was sleeping. In addition, the availability of an appropriate dosing device reduces the risk of incorrect dosing (In a study of infants living with HIV where ARVs were given in syrup and then in tablets when they reached 12 kg, tablets were preferred to syrup by caregivers and children themselves. The main reason for this preference was related to the practical issues of syrup, such as transportation and conspicuousness (Prolonged lamivudine has already proved effective and safe in previous studies (ARV non-adherence can be considered as the main reason for unsuppressed viral load according to previous studies (Limitations were identified in our study, including one related to the conduct of the interviews by the PROMISE-EPI staff. As they followed the participants for several months within the parent study, there was mutual trust, it was easier for staff to reach out to the mothers and for the mothers to express themselves freely. However, this may have induced a social desirability bias. Moreover, those who agreed to be interviewed were more likely to have appreciated the intervention proposed in PROMISE-EPI. This is confirmed by the significant difference in the rate of lost to follow up for the PROMISE-EPI M12 visit between interviewed and non-interviewed mothers.Providing mothers living with HIV with appropriate counseling and giving them the choice of tools to prevent HIV transmission 