Vaccinations saved the lives of around 17m people between 2021 and 2024, but according to the WHO’s Strategic Advisory Group of Experts (SAGE) on Immunisation, global immunisation programmes still face challenges, particularly in middle-income countries and within conflict settings, reports Health Policy Watch.
At a media briefing after SAGE’s biannual meeting this week, Dr Kate O’Brien, WHO director of Immunisation, Vaccines and Biologicals, acknowledged the “deep commitment of countries worldwide to vaccination”, but said while coverage has largely rebounded to pre-pandemic levels, “backsliding in Gavi-ineligible middle-income countries, and an increasing number of people living in fragile and conflict settings, threaten the global gains”.
However, she added, the vast majority of parents are strongly supportive of vaccines.
“The roll-out of the malaria vaccine on the African continent, one of the fastest we’ve seen, is a testament to the impact of vaccines, and the deep desire for people to protect their children and families from infectious diseases that are otherwise a daily occurrence.”
SAGE confirmed that four doses of the malaria vaccine (RTS,S/AS01) provide optimal protection over three doses in preventing the rebound of severe malaria.
This decision was informed by a four-year study, which included children under five in Ghana, Kenya and Malawi, where the vaccine is being rolled out as part of the routine childhood immunisation programmes.
“The fourth dose reduced severe malaria by 54%, with a 30% incremental effectiveness, above that provided by three doses,” said Harvard Professor Dyann Wirth, chair of the Malaria Policy Advisory Group (MPAG).
“The cumulative effectiveness of the four doses in reducing cerebral malaria, one of the most severe and deadly manifestations, was 74%,” she added. In comparison, three doses reduced cerebral malaria by 48%.
SAGE chair Dr Hanna Nohynek said at least 20 countries were using or considering the malaria vaccine, and SAGE recommends aligning the vaccines with other childhood vaccinations where possible.
“SAGE also supports the expanded use of the novel oral poliovirus vaccine (OPV) to reduce vaccine-derived polio virus transmission in select geographies with persistent transmission of this particular virus,” said Nohynek.
Dr Joachim Hombach, SAGE’s executive secretary, highlighted the importance of countries establishing programmes to support trust in vaccines, their safety and their impact, with O’Brien saying the economic return on investment of vaccines is probably one of the highest available.
Over the past 50 years, vaccines have saved around 154m lives, and the measles vaccine is responsible for saving around 60% of these deaths, she noted.
US vaccine decision
The US recently decided to recommend two separate vaccinations for children – a combined one for measles, mumps and rubella (MMR), and another for varicella (chicken pox) – instead of a combined MMRV vaccine for all four conditions.
O’Brien said a range of vaccines were available for the four common childhood infections, and that clinical trials have assessed the safety and the performance of the vaccines when they’re put together in a combination.
SAGE also noted that 16 candidate TB vaccines are in clinical development, five of which are in phase 3 trials. One, known as M72/ASO1E, could be licensed as early as 2028, depending on trial results.
See more from MedicalBrief archives:
Vaccines saved 154m lives over 50 years – Lancet study
WHO, Unicef flag worst decline in childhood immunisations in 30 years
First malaria drug for newborns and babies approved