The period following delivery but before an infant acquires immunity to diseases by natural exposure or immunization — is when infant mortality from infections is highest. Vaccinating pregnant women has shown to be effective in protecting young infants against influenza and pertussis.
Health
Vaccinating pregnant women with Tdap vaccine protects young infants from severe pertussis and hospitalization
Infants less than 2 months old are too young to be vaccinated against pertussis yet are at highest risk of severe disease – – a 75% hospitalization rate and a 1% case fatality rate. A case-control study in six U.S. states found that vaccinating women during the third trimester of pregnancy with Tdap vaccine provided 81% protection against pertussis to infants <2 months and 91% protection against hospitalized cases of pertussis.
Vaccinating pregnant women with Tdap vaccine is 81% effective in preventing pertussis in infants
Vaccinating women during their second or third trimester of pregnancy with the Tdap vaccine was 81% effective in preventing pertussis in their infants in the first two months of life, according to a case-control study in Argentina.
This is one of the first studies to measure the effectiveness of maternal pertussis vaccination in a middle-income country and its findings support Argentina’s decision to introduce the vaccine.
Immunizing pregnant women against influenza reduces the risk of illness and hospitalization in infants
Infants born to mothers who reported receiving influenza vaccination during pregnancy had a 64% lower risk of getting influenza-like illness in their first 6 months of life, a 70% lower risk of laboratory-confirmed influenza, and an 81% lower chance of being hospitalized with influenza than infants whose mothers did not report getting the influenza vaccine during pregnancy. Since influenza vaccines are not effective in children less than 6 months old, immunizing pregnant women against influenza is a public health priority.
Data is from a study spanning more than 8 years at a large healthcare organization in the Western U.S.
HIV-exposed infants are more vulnerable to measles due to lower levels of antibodies
A small hospital-based study in India found that 6 month old infants born to HIV-infected women were 11 times more likely to lack measles antibodies than 6 month olds not exposed to HIV whether or not the exposed infants were themselves infected with HIV. The lack of antibodies in most HIV-exposed infants — making them more vulnerable to measles — may be due to lower levels of measles antibodies in HIV-infected mothers or to poorer transfer of antibodies to the fetus across the placenta.
The introduction of the Hib vaccine in Tamil Nadu led to a 79% decline in meningitis cases in children under two years
In a major children’s hospital in the Indian state of Tamil Nadu, meningitis cases caused by Haemophilus influenzae type b (Hib) in children under two years declined by 79% within two years of the introduction of Hib vaccine. This decline was greater than expected given a vaccination coverage of ~70% for one dose of the vaccine and much greater than expected with a 53% coverage rate for three doses. This suggests that the vaccine protected unvaccinated children through herd immunity.
Introduction of PCV-10 vaccines in Finland reduced invasive pneumococcal disease in unvaccinated children by 33-58%
The rate of invasive pneumococcal disease (IPD) in children too old to be vaccinated (≈1.5 – 10 years old) fell by 33% over a five-year period following the introduction of PCV-10 vaccines in Finland. The rate of IPD caused by serotypes in the vaccine fell by 58% in these children.
The HPV vaccine can protect both young women and men from oropharyngeal cancers
HPV vaccine given to young women may also protect similarly-aged men against oropharyngeal cancers, which have been rising in incidence in the U.S. and Western Europe. In a small study in the UK, rates of oral HPV infections caused by HPV-16 were similar for males 12-24 years of age and vaccinated females (0% vs. 0.5%). This was considerably lower than the rates for unvaccinated females (5.6%) and men ≥25 years old (7.1%).
HPV-16 is the main HPV type linked to oropharyngeal cancers.
Immunization with PCV reduced the risk of pneumococcal pneumonia in HIV-positive adults in Kenya
Prior to the introduction of PCV, adults with HIV in a rural area of Kenya were nearly five times more likely to have pneumococcal pneumonia than non-infected adults, and the majority of cases with bacteremia (blood infection) occurred in HIV positive individuals.
PCV-10 vaccine reduced rates of pneumococcal pneumonia in adults in Kenya, including those with HIV
The introduction of PCV-10, along with a “catch-up” campaign for 1-4 year olds, led to dramatic reductions in the rates of pneumococcal pneumonia in adults (≥18 years old) in a rural area of Kenya with high rates of both adult pneumococcal pneumonia and HIV. Over five years following the vaccine introduction, the incidence rates among adults were 47-94% lower each year than in the pre-vaccine period, with similar declines for HIV-infected and HIV-uninfected adults.