Risk and rates of hospitalisation in young children: a prospective study of a South African birth cohort
Authors: Wedderburn Catherine J , Bondar Julia , Lake Marilyn T , Nhapi Raymond , Barnett Whitney , Nicol Mark P , Goddard Liz , Zar Heather J 
Published: June 2023

Introduction

Children in sub-Saharan Africa (SSA) are disproportionately affected by morbidity and mortality; there is also a growing vulnerable population of children who are HIV-exposed uninfected (HEU). Understanding reasons and risk factors for early-life child hospitalisation will help optimise interventions to improve health outcomes. We investigated hospitalisations from birth to two years in a South African birth cohort.

Methods

Mother-child pairs in the Drakenstein Child Health Study were followed from birth to two years with active surveillance for hospital admission and investigation of aetiology and outcome. Incidence, duration, cause, and factors associated with child hospitalisation were investigated, and compared between HEU and HIV-unexposed uninfected (HUU) children

Results

Of 1136 children (247 HEU; 889 HUU), 314 (28%) children were hospitalised in 430 episodes despite >98% childhood vaccination coverage. The highest hospitalisation rate was from 0-6 months, decreasing thereafter; 20% (84/430) of hospitalisations occurred in neonates at birth. Amongst hospitalisations subsequent to discharge after birth, 83% (288/346) had an infectious cause; lower respiratory tract infection (LRTI) was the most common cause (49%;169/346) with respiratory syncytial virus (RSV) responsible for 31% of LRTIs; from 0-6 months, RSV-LRTI accounted for 22% (36/164) of all-cause hospitalisations. HIV exposure was a risk factor for hospitalisation in infants (IRR 1.63 [95% CI 1.29-2.05]) and longer hospital admission (p=0.004). Prematurity (HR 2.82 [95% CI 2.28-3.49]), delayed infant vaccinations (1.43 [1.12-1.82]), or raised maternal HIV viral load in HEU infants were risk factors; breastfeeding was protective (0.69 [0.53-0.90]).

Conclusion

Children in SSA continue to experience high rates of hospitalisation in early life. Infectious causes, especially RSV-LRTI, underly most hospital admissions. HEU children are at particular risk in infancy. Available strategies such as promoting breastfeeding, timely vaccination, and optimising antenatal maternal HIV care should be strengthened. New interventions to prevent RSV may have a large additional impact in reducing hospitalisation.

KEY QUESTIONS

What is already known?

The Sustainable Development Goals highlight the need to prevent child morbidity and mortality. However, there are limited recent data on hospitalisation rates and determinants in sub-Saharan Africa (SSA), including in children who are HIV-exposed and uninfected (HEU), despite this region having the highest under-5 mortality rate.

Children who are HEU represent a growing vulnerable population in SSA.

What are the new findings?

Early-life hospitalisation occurred in 28% of children in our cohort, most frequently in the first 6 months of life, despite high vaccination coverage including the 13-valent pneumococcal conjugate vaccine (PCV) and excluding paediatric HIV infection.

Infectious causes represented 83% of hospital admissions after birth; lower respiratory tract infection (LRTI) caused most hospitalisations (49%), with RSV accounting for 31% of episodes. In the first 6 months of life RSV-LRTI was responsible for 22% of all-cause hospitalisations and for 41% of LRTI hospitalisations.

Children who are HEU had higher rates of hospitalisation in infancy through 12 months, compared to HIV-unexposed and uninfected children (HUU), as well as longer hospital stay.

Prematurity or delayed vaccination were associated with higher risk of hospitalisation; detectable maternal HIV viral load was associated with higher hospitalisation rates in HEU children; breastfeeding was protective against hospitalisation, particularly from gastrointestinal causes.

What do the new findings imply?

Young children in SSA continue to experience high rates of hospitalisation and infectious causes underly most hospital admissions.

Renewed focus on measures to prevent hospitalisation in young children is needed, including interventions to encourage breastfeeding practices, timely vaccinations, optimal maternal health, and targeting at-risk children including those who are HEU or premature.

New interventions against RSV-LRTI may substantially reduce hospitalisation in LMICs.