The Evolving Pediatric HIV Epidemic in Rural Southern Zambia: The Beneficial Impact of Advances in Prevention and Treatment at a District Hospital From 2007 to 2019

Abstract

Background: Remarkable progress has been made in expanding access to services addressing the pediatric HIV epidemic, including programs to prevent mother-to-child transmission, early diagnosis and treatment for children living with HIV. Few long-term data are available from rural sub-Saharan Africa to assess implementation and impact of national guidelines.

Methods: Results from 3 cross-sectional studies and 1 cohort study conducted at Macha Hospital in Southern Province, Zambia from 2007 to 2019 were summarized. For infant diagnosis, maternal antiretroviral treatment, infant test results and turnaround times for results were evaluated by year. For pediatric HIV care, the number and age of children initiating care and treatment, and treatment outcomes within 12 months were evaluated by year.

Results: Receipt of maternal combination antiretroviral treatment increased from 51.6% in 2010-2012 to 93.4% in 2019, and the proportion of infants testing positive decreased from 12.4% to 4.0%. Turnaround times for results returning to clinic varied but were shorter when labs consistently used a text messaging system. The proportion of mothers receiving results was higher when a text message intervention was piloted. The number of children living with HIV enrolled into care and the proportion initiating treatment with severe immunosuppression and dying within 12 months decreased over time.

Conclusions: These studies demonstrate the long-term beneficial impact of implementing a strong HIV prevention and treatment program. While expansion and decentralization brought challenges, the program succeeded in decreasing the rate of mother-to-child transmission and ensuring that children living with HIV benefit from access to life-saving treatment.

Figure 1.

A) Percent of women living with HIV receiving antiretroviral therapy during pregnancy by year; B) Percent of infants who tested HIV positive by year, showing maternal antiretroviral regimen; C) Percent of infants who tested HIV positive by year and maternal antiretroviral regimen during pregnancy ART: antiretroviral therapy; scART: short-course ART; cART: combination ART; sdNVP: single dose nevirapine Note: Sample sizes are provided in parentheses after the year. The sample sizes in 1A and 1B/C do not match as some infants did not have valid test results available.

Figure 2.

Turnaround time for test results from infant diagnosis of HIV by year Note: Grey dashed line at 28 days represents the WHO recommended time to return results to the mother/caregiver.

Figure 3.

A) Enrollment into the Pediatric Antiretroviral Therapy (PART) Study by year; B) Enrollment into care at the Macha HIV clinic by year; and C) Treatment initiation by year Note: Panel A shows the number of participants enrolling in the study by calendar year starting in 2007 when the study began and ending in 2019 (end of analysis). Panel B shows the number of study participants enrolling into care by calendar year. As participants enrolling in the study may have previously enrolled into care, particularly in the early years of the study, the time period starts in 2005 when the HIV clinic opened and ends in 2019. A small number of participants (n=48 out of 949; range: 0-7 per year) transferred into HIV care after having initiated treatment at another clinic. Panel C shows the number of study participants initiating treatment by calendar year. As some participants in the study previously initiated treatment either at the Macha HIV clinic or at another clinic, the time period starts in 2004 and ends in 2019.

Figure 4.

Distribution among study participants of A) age at registration for care at the Macha HIV clinic by year; B) age at treatment initiation by year; C) level of immune suppression at treatment initiation by year Note: Sample sizes are provided in parentheses after the year. Children who transferred to the Macha HIV clinic already receiving treatment were excluded. Immune suppression defined according to WHO guidelines based on age and CD4+ T-cell percentage or count (0-11 months: none/mild - ≥30%, advanced – 25-29%, severe - <25%; 12-35 months: none/mild - ≥25%, advanced – 20-24%, severe - <20%; 36\59 months: ≥20%, advanced – 15\19%, severe - <15%; ≥5 years: none/mild - ≥350, advanced – 200\349, severe - <200 or <15%).

Figure 5.

Distribution of outcomes among study participants after A) 6 months and B) 12 months of treatment by year of initiation. Note: Sample sizes are provided in parentheses after the year. The analysis was limited to children who initiated treatment after enrolling into the study. Children who had not died or transferred to another clinic were considered to still be in care if their last follow-up visit occurred within 3 months of the date of administrative censoring (6 or 12 months after treatment initiation).