Better use of existing pneumonia and typhoid vaccines as well as new TB and pneumonia vaccines that are currently in clinical trials, could save over half a million deaths annually from drug resistant pathogens that don’t respond to antibiotics, according to a new WHO report on how vaccine strategies can reduce antimicrobial resistance (AMR).

And over a longer term, better use of existing vaccines as well as the development of new vaccines against 24 deadly pathogens could reduce the number of antibiotics needed by 22% or 2.5 billion defined daily doses globally every year, supporting worldwide efforts to address AMR, according to the report, published on Thursday.

“Antimicrobial resistance in reality, is a sort of a race between the microbes or the bugs that are getting smarter to evade the antimicrobials, with the antibiotics and the new medicines,” said Yvan J-F. Hutin, Director of Surveillance, Prevention and Control, AMR Division, WHO, at a press conference on Thursday discussing the report.

Along with more judicious use of available drugs, preventing diseases from ever occurring is a critical AMR strategy, he added. And along with better water, sanitation and hygiene, vaccination is an important, but oft-overlooked AMR prevention tool.

“Within the prevention pillar, vaccination is really important,” Hutin said. That means, “using the vaccines that we have today to increase the coverage, and pushing the vaccines that are close to the finish line, in terms of research and development, like TB, and having the vision to say that for certain pathogens, certain microbes, we don’t have the vaccine yet, but it would make a lot of sense to have this these vaccines.”

Prioritizing vaccine development to prevent AMR deaths, as well as deaths from the disease

“We’ve known for many years that vaccines could play a role in controlling or contributing to the control of antimicrobial resistance, but we haven’t, up until today, been able to say which vaccines and what the impact really could be,” added Martin Friede, Head of the Product & Delivery Research team, within WHO’s Department of Immunization, Vaccines and Biologicals.

“Vaccines have been developed for the last 50 years based on the prioritization,.. of deaths that happened due to that pathogen,” he added.  But that ignored the ancillary effect of pathogen drug resistance when people became ill, and antibiotic treatments failed. “This latest report, however, adds in the element of avoidable deaths from drug resistant pathogens. So now we have a new metric against which we can incorporate into our prioritization methodologies and say, well, not only can we prevent deaths due to the pathogen, but we can prevent antibiotic use.

“We have a good start citing point which to say, these are the vaccines, these are the pathogens where we would have the greatest impact,” on reducing AMR.

There are an estimated 1.13 million deaths annually due to drug resistant pathogens – and more than five million deaths overall are attributable directly indirectly to AMR, according to the latest WHO research.

The report estimates that wider use of already available vaccines against Haemophilus influenzae type B (Hib), a bacteria causing both pneumonia and meningitis, as well as typhoid vaccines could avert up to 106 000 of the deaths annually associated with the development of AMR from antibiotic use when unvaccinated children and adults become ill.

Every year, vaccines against Streptococcus pneumoniae could save 33 million antibiotic doses, if the Immunization Agenda 2030 target of 90% of the world’s children were vaccinated, as well as older adults. Vaccines for typhoid could save 45 million antibiotic doses, if their introduction was accelerated in high-burden countries.

And wider application of brand new malaria vaccines now being rolled out, could save up to 25 million antibiotic doses, which are often misused to try to treat malaria, which is caused by the Plasmodium falciparum parasite and other related strains, not a bacteria.

Tuberculosis vaccines would make a major dent in AMR deaths

TB vaccines could have the highest impact once experimental vaccines  now in clinical trials are approved and widely available, the report finds.  That’s a particular priority given the widening arc of multi-drug resistant forms of TB. Administration of 1.2-1.9 billion antibiotic doses could be averted – a significant portion of the 11.3 billion doses used annually against the diseases covered in the report. Nearly 200,000 more deaths associated with AMR could thus be averted annually.

Further down the line, vaccines for other deadly pathogens such as Klebsiella pneumoniae, in early stage development could save several hundred thousand more lives, once they are available.

Vaccines could significantly reduce the substantial economic costs of AMR

Globally, the hospital costs of treating resistant pathogens evaluated in the report are estimated at US$ 730 billion each year. If vaccines could be rolled out against all the evaluated pathogens, they could save a third of the hospital costs associated with AMR, the report’s authors also concluded.

“The actual cost of treating these infections is incredibly high, $730 billion every year,” Hutin said. “And what we have found that if we put together all the vaccines that we had evaluated, if we have a scenario that they could be widely used, that reaches those people who need these vaccines, that could avert up to a third of these costs, so quite a large, substantial, quite a large proportion that could contribute to reduction of AMR.”

Image Credits: Twitter:@WHO, UNICEF 2024 , WHO , WHO PAHO.