Routine childhood immunisation during the COVID-19 pandemic in Africa: a benefit–risk analysis of health benefits versus excess risk of SARS-CoV-2 infection
Autor
Abbas, Kaja
Procter, Simon R
Zandvoort, Kevin van
Clark, Andrew
Funk, Sebastian
Mengistu, Tewodaj
Hogan, Dan
Dansereau, Emily
Jit, Mark
Flasche, Stefan
Institución
Resumen
Background National immunisation programmes globally are at risk of suspension due to the severe health system
constraints and physical distancing measures in place to mitigate the ongoing COVID-19 pandemic. We aimed to
compare the health benefits of sustaining routine childhood immunisation in Africa with the risk of acquiring severe
acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection through visiting routine vaccination service delivery
points.
Methods We considered a high-impact scenario and a low-impact scenario to approximate the child deaths that could
be caused by immunisation coverage reductions during COVID-19 outbreaks. In the high-impact scenario, we used
previously reported country-specific child mortality impact estimates of childhood immunisation for diphtheria,
tetanus, pertussis, hepatitis B, Haemophilus influenzae type b, Streptococcus pneumoniae, rotavirus, measles, meningitis
A, rubella, and yellow fever to approximate the future deaths averted before 5 years of age by routine childhood
vaccination during a 6-month COVID-19 risk period without catch-up campaigns. In the low-impact scenario, we
approximated the health benefits of sustaining routine childhood immunisation on only the child deaths averted
from measles outbreaks during the COVID-19 risk period. We assumed that contact-reducing interventions flattened
the outbreak curve during the COVID-19 risk period, that 60% of the population will have been infected by the end of
that period, that children can be infected by either vaccinators or during transport, and that upon child infection the
whole household will be infected. Country-specific household age structure estimates and age-dependent infectionfatality rates were applied to calculate the number of deaths attributable to the vaccination clinic visits. We present
benefit–risk ratios for routine childhood immunisation, with 95% uncertainty intervals (UIs) from a probabilistic
sensitivity analysis.
Findings In the high-impact scenario, for every one excess COVID-19 death attributable to SARS-CoV-2 infections
acquired during routine vaccination clinic visits, 84 (95% UI 14–267) deaths in children could be prevented by
sustaining routine childhood immunisation in Africa. The benefit–risk ratio for the vaccinated children is
85 000 (4900–546000), for their siblings (<20 years) is 75 000 (4400–483000), for their parents or adult carers (aged
20–60 years) is 769 (148–2700), and for older adults (>60 years) is 96 (14–307). In the low-impact scenario that
approximates the health benefits to only the child deaths averted from measles outbreaks, the benefit–risk ratio to the
households of vaccinated children is 3 (0–10); if the risk to only the vaccinated children is considered, the benefit–risk
ratio is 3000 (182–21000).
Interpretation The deaths prevented by sustaining routine childhood immunisation in Africa outweigh the excess
risk of COVID-19 deaths associated with vaccination clinic visits, especially for the vaccinated children. Routine
childhood immunisation should be sustained in Africa as much as possible, while considering other factors such as
logistical constraints, staff shortages, and reallocation of resources during the COVID-19 pandemic.