ABSTRACT
Oral polio vaccine (OPV) campaigns, but not other campaigns, have been associated with major reductions in child mortality. Studies have shown that OPV reduces the risk of respiratory infections. We analysed the causes of death at 0-2 years of age in Chakaria, a health and demographic surveillance Systems in Bangladesh, in the period 2012-2019 where 13 national campaigns with combinations of OPV (n = 4), vitamin A supplementation (n = 9), measles vaccine (MV) (n = 2), and albendazole (n = 2) were implemented. OPV-only campaigns reduced overall mortality by 30% (95% confidence interval: -10-56%). Deaths from respiratory infections were reduced by 62% (20-82%, p = 0.01) in the post-neonatal period (1-35 months), whereas there was as slight increase of 19% (-37-127%, p = 0.54) for deaths from other causes. There was no benefit of other types of campaigns. Hence, the hypothesis that OPV may have beneficial non-specific effects, protecting particularly against respiratory infections, was confirmed.