Data obtained through active surveillance pre and post introduction of PCV in the US showed that the vaccine averted an estimated 38,000 cases of invasive pneumococcal disease within its first five years of use. Additionally, 71,000 cases of disease were estimated to be prevented by herd effects.
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Cancer survivors experience much higher complications from vaccine-preventable infections
In survivors of pediatric and young adult cancers in the US, the risk of mortality from infectious complications is 4 times higher than in their cancer-naïve siblings. Within the first five years after cancer diagnosis, the risk of some vaccine-preventable infections such as pneumonia and hepatitis is more than 9-fold and 6-fold higher, respectively. More than 5 years after cancer diagnosis, the risk of these two infections remains high at 3.7 and 2.5 times higher than siblings.
Higher vaccine coverage for some vaccines was associated with a lower risk of developing a specific type of leukemia
A study including thousands of children from the U.S. state of Texas found that children born in counties with high coverage of HepB, Polio, and Hib vaccines were 33%, 37%, and 42% less likely to develop a specific type of leukemia than children born in counties with lower coverage of each vaccine.
Influenza vaccine during pregnancy is linked to lower rates of prematurity and small for gestational age births
This study, conducted in the United States, demonstrates an association between immunization with the inactivated influenza vaccine during pregnancy and reduced likelihood of prematurity during local, regional, and widespread influenza activity periods. Moreover, during the period of widespread influenza activity there was an association between maternal receipt of influenza vaccine and reduced likelihood of small for gestational age (SGA) birth.
Long-term cancer survivors have an increased risk of later HPV infections
In a US-based study of more than 65,000 long-term survivors of pediatric and young adult cancers spanning nearly three decades, researchers found an increased risk of later HPV infections and malignancies among these survivors. Female survivors of childhood and young adult cancers were found to have a 40% greater chance of developing HPV-associated malignancies compared to cancer-naïve females. This risk was even greater in male cancer survivors who had a 150% relative excess of HPV malignancies compared to cancer-naive males.
High incidence of diarrhea in young children can be associated with lower cognitive test scores
A study looking at the long term cognitive deficits faced by children in an urban Brazilian shantytown with high incidence of diarrhea in the first two years of life showed that this cohort scored significantly lower on 3/5 types of test measuring cognitive function at ages 6-10 compared to children who did not suffer recurrent bouts of early childhood diarrhea. In particular, the children who suffered from persistent early childhood diarrhea scored lower on tests assessing nonverbal intelligence (TONI) and IQ through assessing ability to match symbols to numbers (WISC-III Coding task) and short-term memory (WISC-III digit scan).
Measles infection suppresses the immune system for up to 3 years after infection
In a study of data from England & Wales, Denmark, and the US, it was shown that measles infection suppresses the immune system for up to 3 years after infection, increasing the risk of death due to other childhood infections during that time. This means that prevention of measles significantly impacts overall health during critical childhood years.
Early childhood diarrhea has been shown to hinder school readiness and performance
In a study of children in a Brazilian shantytown, researchers found that the greater the number of episodes of persistent diarrhea before age two, the more delayed a child was in terms of school readiness. Overall, each episode of diarrhea delayed a child’s starting school by 0.7 months. Likewise, 6-10 years later, increasing episodes of diarrhea before age two predicted delays in age-appropriate educational attainment.
Childhood vaccination against Hepatitis A is cost-effective
In Argentina, universal vaccination for Hepatitis A in children, at 95% vaccine coverage, can prevent over 350,000 hepatitis A infections per year and 428 deaths. Benefits persist at coverage rates as low as 70% with over 290,000 prevented infections. At 95% coverage rates, this program would save almost $24,000 annually.
Cancer patients are at greater risk of vaccine-preventable infections
A study in the US found that the incidence of invasive pneumococcal disease was 22 to 38 times higher in adults with cancer than in healthy adults.