Immunizing pregnant women protects infants from influenza, with 56% efficacy in the first 2 months of life

A pooled analysis of three randomized controlled trials conducted in Nepal, Mali, and South Africa between 2011 and 2014 found that immunization during pregnancy provided protection against influenza to young infants from birth through 4 months of age. Protection against infant influenza was greatest in the first 2 months of life, with 56% efficacy, and the pooled efficacy of maternal vaccination to prevent infant laboratory-confirmed influenza up to 6 months of age was 35%.

Influenza vaccination during pregnancy reduces severe pneumonia rates in infants, especially during peak influenza circulation

An analysis of data from three studies showed that the rates of severe pneumonia in infants in their first six months of life was 20% lower overall in infants whose mothers received the influenza vaccination during pregnancy than in infants whose mothers had not, and the rates of severe pneumonia was 56% lower during periods when influenza circulation was highest. These findings correspond with evidence that influenza infection predisposes individuals to pneumococcal infection.

The incidence rate of severe pneumonia in the vaccine group compared to the control group was 43% lower in South Africa, 31% lower in Nepal, but not significantly different in Mali.

The empowerment of women is associated with higher odds of childhood vaccinations

A systematic review of studies from countries in Africa and Southeast Asia investigated the relationship between a woman’s “agency” (defined as the woman’s ability to state her goals and to act upon them with motivation and purpose) and childhood immunizations in lower-income settings. The review found a general pattern among studies in which higher agency among mothers was associated with higher odds of childhood immunizations. Empowering women in these settings shows promise as a means to improve child health.

Undernourished children have a higher likelihood for diarrhea and pneumonia but immunization can improve infant growth

Multiple studies show that

  1. Diarrhea and pneumonia impair children’s growth and that underlying malnutrition is a major risk factor for these conditions.
  2. “Episodes of diarrhea may predispose to pneumonia in undernourished children” and
  3. Immunization against influenza (in mothers) and Streptococcus pneumoniae may improve infant growth. In addition, new studies from Bangladesh, Colombia, Ghana, and Israel further support the paradigm that malnutrition is a key risk factor for diarrhea and pneumonia.

Vaccines are most cost-effective in low income countries

An analysis of the impact of rotavirus vaccine in 25 countries found that the rates of vaccination in all countries were highest and risk mortality lowest in the top two wealth quintile’s coverage. Countries differed in the relative inequities in these two underlying variables. Cost per DALYs averted in substantially greater in the higher quintiles. In all countries, the greatest potential vaccine benefit was in the poorest quintiles; however, reduced vaccination coverage lowered the projected vaccine benefit.