Nutritional Advice El Mondo
Objectives:
Bacillus Calmette-Guérin (BCG), diphtheria-tetanus-pertussis (DTP) and standard titre measles containing vaccines (MCV) have prevented countless illnesses and deaths among infants and children worldwide, especially those living in the world’s poorest countries.
The objectives of this review article are to review evidence on associations between receipt of these vaccines and childhood mortality, with a focus on effects beyond those attributable to the targeted diseases.
Study design:
This review article included 34 birth cohort studies (17 birth cohorts for BCG vaccine, 17 birth cohorts for DTP vaccine and 27 birth cohorts for MCV. 5 results for BCG vaccine were from clinical trials, as were 4 results for MCV. Three, zero and seven articles reported results for non-specific mortality for BCG, DTP and MCV, respectively).
Most studies reported on all cause (rather than non-specific) mortality.
Ages at MCV vaccination were available, they were typically around 9 months, ranging from 4.5 months in a clinical trial to median 15.8 months in a cohort study.
There was insufficient evidence to determine whether any difference exists in effect of DTP according to vitamin A supplementation status.
Results and conclusions:
The investigators found in 5 clinical trials that BCG vaccine non-significantly reduced all cause mortality with 30% [average relative risk = 0.70, 95% CI = 0.49 to 1.01].
The investigators found in 9 observational studies at high risk of bias that BCG vaccine significantly reduced all cause mortality with 53% [average relative risk = 0.47, 95% CI = 0.32 to 0.69, I2 = 63%].
The investigators found in 10 studies at high risk of bias that DTP vaccine (almost always with oral polio vaccine) non-significantly increased all cause mortality with 38% [relative risk = 1.38, 95% CI = 0.92 to 2.08]; this effect seemed stronger in girls than in boys.
The investigators found in 4 clinical trials that standard titre MCV non-significantly decreased all cause mortality with 26% [relative risk = 0.74, 95% CI = 0.51 to 1.07, I2 = 0%]; this effect seemed stronger in girls than in boys.
The investigators found in 18 observational studies at high risk of bias that standard titre MCV significantly decreased all cause mortality with 49% [relative risk = 0.51, 95% CI = 0.42 to 0.63, I2 = 64%]; this effect seemed stronger in girls than in boys.
The investigators found in 7 observational studies at high risk of bias that administering DTP with or after MCV may be associated with higher mortality than administering it before MCV.
The investigators concluded evidence suggests that receipt of BCG and MCV reduce overall mortality by more than would be expected through their effects on the diseases they prevent, and receipt of DTP may be associated with an increase in all cause mortality. Although efforts should be made to ensure that all children are immunised on schedule with BCG, DTP and MCV, randomised trials are needed to compare the effects of different sequences.
Original title:
Association of BCG, DTP, and measles containing vaccines with childhood mortality: systematic review by Higgins JP, Soares-Weiser K, […], Reingold AL.
Link:
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5063034/
Additional information of El Mondo:
Find more information/studies on food fortification/malnutrition right here.