The introduction of vaccines dramatically reduced the burden of many diseases worldwide. Recent research has also begun to examine whether there might be other benefits, either directly or downstream, to vaccination programs.
The investigators of a new study, published in Social Science & Medicine,
have shown that the introduction of a Universal Immunization Program (UIP) in India was associated with improved school attainment.
The introduction of a UIP in India was a substantial factor in reducing the number of deaths among children under 5 years in the country from 3.4 million to 1.2 million between 1990 through 2015. Vaccine preventable diseases are also linked to stunting in childhood, which can lead to poor growth and learning difficulty.
The UIP currently includes BCG, measles, DPT, OPV, inactivated polio vaccine, hepatitis B, and Hib-containing pentavalent vaccine. In some areas the UIP includes Japanese encephalitis, rotavirus, pneumococcal, and measles-rubella vaccines.
The study team combined 1985-1990 district-level rollout data for the UIP from India’s Ministry of Health and Family Welfare with data from the National Family Health Survey of India 2015-16.
Due to the creation of new states and the division of districts, India has significantly more districts today than in the past. The investigators had to match the 353 districts that India was divided into during the initial rollout of UIP to the 722 districts that the country consisted of in 2019.
The analysis compared 109,908 adults who were born either in the 5 years before or 5 years after the 1985-1990 rollout period, comparing only those who lived in the same location. Household, locality, district, and state fixed-effects linear regression models incorporated socioeconomic and community resource access into the analysis.
At the household level of analysis, individuals born after the UIP rollout attained 0.18 (95% CI: 0.02, 0.33; P < 0.05) more schooling grades than control group adults from the same household.
At the village or city ward level, individuals attained 0.23 (95% CI: 0.13, 0.32; P< 0.001) more schooling grades than those in the control group.
At the district and state fixed-analysis levels, those born after the UIP rollout attained 0.29 (95% CI: 0.19, 0.38; P< 0.001), and 0.25 (95% CI: 0.1, 0.39; P< 0.01) more schooling grades than the control group respectively.
Subgroup analysis revealed that the positive associations between UIP rollout and schooling grades were observed most among women and among higher income households.
“In the subsample of women, intervention group women attained 0.29 (95% CI: 0.04, 0.54; P < 0.05) more schooling grades as compared with control group women from the same household,” the study authors wrote.
The study authors explained that these results aligned with prior research on early childhood development in India, wherein investment of resources like health care and nutrition in girls is lower than that in boys. Therefore, they propose, public programs like the UIP might have a more noticeable positive effect among Indian girls.
“We found that nonmigrant 20–36 year old adults who were born when or after the Universal Immunization Programme was implemented in their district of residence attained 0.18–0.29 more grades of schooling, as compared with those born before the UIP,” study authors summarized.
Exposure to the UIP was ultimately associated with between 0.6-0.7 additional grades of schooling attained when the age range was expanded to all non-migrant 18-54 year old men and 18-49 year old women.
They also cited literature that linked the UIP to increased height due to decreased childhood stunting.
The study results indicate that the UIP has been positive for the health and educational attainment of India’s children, but full vaccine coverage is still only 62%.
“Our findings reemphasize the need for universal coverage of routine childhood vaccines in India,” study authors wrote.
It should be noted that imperfect vaccine coverage is not limited to low and middle income countries. In the United States, there are pockets of vaccine hesitancy
and mistrust of vaccines which could spark the return of vaccine preventable disease outbreaks. Improving trust between clinicians and holdout communities
will be key in all countries wherein resource barriers to vaccination are superseded.
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