A surveillance study over a 10-year period in the Gambia found that routine introduction of PCV led to a 33% reduction in the incidence of radiological pneumonia and a 27% decline in pneumonia hospitalizations in children. Reducing the rate of pneumococcal disease will not only save lives but will also reduce the substantial economic burden placed on families and health systems.
A systematic review of the global burden of acute lower respiratory infections associated with seasonal influenza in children under 5 years found that just in 2018 these infections led to an estimated 870,000 hospital admissions and 15,300 in-hospital deaths. About 23% of these hospital admissions and 36% of the in-hospital deaths were in infants under 6 months and about 82% of the in-hospital deaths occurred in low-income and lower-middle-income countries.
Prior to the introduction of rotavirus vaccines in the U.S., there were an estimated 205,000 – 272,000 emergency department visits and 55,000 – 70,000 hospitalizations due to rotavirus in children each year. A series of studies found that hospitalizations in children under five due to rotavirus declined, on average by 80% from the pre-vaccine to the post-vaccine era, while both outpatient visits and emergency department visits due to rotavirus declined 57%.
Several studies in the U.S. have shown that hospitalizations due to rotavirus fell sharply in children too old to be vaccinated as well as in adults after rotavirus vaccines were introduced, indicating herd protection. In one large study, rotavirus hospitalizations in 2008 — two years after the first vaccine was introduced — declined by 71% in 5-14 year old children and by 65% in 15-24 year olds compared to the pre-vaccine period.
In New Zealand, Maori and Pacific children have historically suffered high hospitalization rates for invasive pneumococcal disease (IPD), all cause pneumonia (ACP), and otitis media. Following the introduction of conjugate vaccines in the country, Maori and Pacific children’s rates of admission for IPD dropped by 79% and 67%, respectively, while significant reductions in ACP and otitis media admissions were also noted, resulting in reductions in disparities for these populations.
In a Bangladeshi study, pneumonia and acute diarrhea were the first and third most common reasons for childhood hospital admission with over half (54%) of the acute diarrhea admissions caused by rotavirus. One in four children taken to this large pediatric hospital were refused admission because all beds were occupied. Vaccination could have prevented children with rotavirus from requiring essential hospital resources when one in four children refused admission had symptoms of pneumonia.
Several countries have seen a significant decrease in the number of rotavirus-related hospital admissions in rotavirus unvaccinated children ages 2-5 years who were not age eligible to receive the vaccine post introduction. The US had a 41-92% decrease, Australia had a 30-70% decrease, Belgium had a 20-64% decrease, Austria had a 35% reduction and El Salvador had a 41-81% decrease. In addition, there was a reduction in hospitalizations due to gastroenteritis of any cause by 17-51% in the US and 40% in Australia.