A new study reveals that a vaccine against a major cause of childhood illness and mortality in the world has sharply reduced the incidence of serious pneumococcal disease among Kenyan children since it was introduced in 2011.
The Johns Hopkins Bloomberg School of Public Health study reveals that after the vaccine against Streptococcus pneumoniae was introduced, the average annual incidence of serious pneumococcal disease dropped by 92 percent among children aged under five.
S. pneumoniae infection can cause many serious conditions, which are broadly termed “pneumococcal disease” and include pneumonia, meningitis, ear and sinus problems, and sepsis (blood infection).
The research which examined two time periods, 1999-2010, before the vaccine’s introduction and 2012-2016 after the introduction of Synflorix, which is designed to protect against 10 common strains of S. pneumoniae found that the vaccines have saved thousands of lives.
“The researchers calculated the incidence, or annual rate per capita, of serious (“invasive”) pneumococcal disease cases involving the 10 PCV10 strains in children less than five years old at the hospital during the years 1999-2016.
They then compared the average incidence during the 1999-2010 pre-vaccine period to the average incidence in 2012-2016 after the vaccine was in routine use.
They found that the incidence of invasive pneumococcal disease in children under five, involving those 10 pneumococcal strains, declined 92 percent, reads the report in part.
The researchers tied the success of the vaccine to the herd community, which is the inability of a disease to travel through a population because too many individuals are immune to it that disease transmission halts.
Kenya did not until 2011 have a pneumococcal vaccine in its national childhood immunisation schedule.
However, through the assistance of Gavi, the Vaccine Alliance, it introduced Synflorix vaccine which provided for a three-dose schedule of PCV10 vaccination in infants at six, 10 and 14 weeks of age, with initial “catch-up” vaccination in 2011 for children aged under one.