Research in Australia on new pneumonia vaccines show that while pneumonia in children is being suppressed, empyaema is increased.
The research, which was led by the University of New South Wales (UNSW), examined the impact of the new 13-valent pneumococcal conjugate vaccine (13vPCV) on childhood pneumonia and empyaema.
Empyaema, which is the collection of pus in the lungs, occurs in about 1% of children with pneumonia. In children, empyaema is far less fatal than it is in adults, but it does extend hospitalisation, requiring antibiotics and surgery or installation of a drain.
The findings of the study showed that while 13vPCV resulted in a 21% drop in childhood pneumonia hospitalisations, there was a contemporaneous 25% rise in empyaema hospitalisations.
According to senior author Professor Adam Jaffe, Head of the School of Women’s and Children’s Health at UNSW Medicine & Health, said the findings suggested an emergence of non-vaccine serotypes—those which 13vPCV does not cover.
13vPCV was introduced to cover the 13 most common serotypes that cause invasive pneumococcal infection, adding six more serotypes over the seven serotypes covered by its predecessor, 7cPCV.
Prof Jaffe said: “Although we found a substantial reduction in serotype 1, serotype 3 is now the predominant organism which causes childhood empyema—in 76% of cases—so, efforts must be made to create a vaccine which is more effective against serotype 3.
“In fact, Australia recently changed the vaccination dosage schedule to try and improve the effectiveness of 13vPCV against serotype 3, but we need to continue monitoring patients using molecular techniques to see if this change has had an impact.
“Childhood bacterial pneumonia and empyema are potentially preventable diseases through vaccination. So, if Australia can develop an effective vaccine, we could prevent children from being hospitalized with pneumonia and empyema.”
The researchers conducted a similar study over four years during the 7vPCV era.
“Our new study had two parts,” Prof Jaffe said. “We analysed national hospitalisations for childhood empyaema and childhood pneumonia, then we conducted an enhanced surveillance study on children with empyaema.”
The first part of the research used publicly available hospitalisations data to find out if the introduction of 13vPCV changed how many children were admitted to hospital with pneumonia and empyaema.
The enhanced surveillance study involved the collection of blood and lung fluid samples from 401 children with empyaema, followed by molecular testing on these samples and comparing the results to their previous study undertaken during the period of 7vPCV.
Prof Jaffe said research with a larger sample was ongoing, and 13vPCV monitoring was needed.
Source: Medical Xpress
Journal information: Roxanne Strachan et al. Assessing the impact of the 13 valent pneumococcal vaccine on childhood empyema in Australia, Thorax (2021). DOI: 10.1136/thoraxjnl-2020-216032
