By Elisha Singira
With nearly five million deaths per year attributed to resistant bacterial infections and over one million deaths directly linked to antimicrobial resistant (AMR), the World Health Organization (WHO) has called on countries to accelerate trials for AMR related vaccines in late-stage development and maximize the use of existing vaccines.
AMR is a major growing health concern that occurs when bacteria, viruses, and fungi mutate and no longer respond to medicines making treatment difficult, as such, WHO notes that vaccines have the potential to prevent the spread of AMR since they play a crucial role in preventing infections.
“Preventing infections using vaccination reduces the use of antibiotics, which is one of the main drivers of AMR. Yet of the top six bacterial pathogens responsible for deaths due to AMR, only one, pneumococcal disease has a vaccine. Therefore, there is a need to have equitable and global access to vaccines that already exist especially in remote settings,” said Dr. Hanan Balkhy, WHO Assistant Director-General, Antimicrobial Resistance.
According to the first-ever report focusing on the pipeline of vaccine currently in development to prevent infections caused by AMR bacterial pathogens, there are 61 vaccine candidates in various stages of clinical development. Though some of them are in late stages of development, WHO notes that they will not be available anytime soon.
At the moment, the report notes that there are four vaccines available against bacterial pathogens including pneumococcal disease (Streptococcus pneumoniae), Hib (Haemophilus influenzae type b) Tuberculosis (Mycobacterium tuberculosis) and Typhoid fever (Salmonella Typhi). However, the current Bacillus Calmette-Guerin (BCG) vaccines against Tuberculosis do not adequately protect therefore, more effective vaccines against TB should accelerated.
While the remaining three vaccines are effective, we need to increase the number of people receiving them to contribute to a reduction in the use of antibiotics and prevent further deaths, the report notes.
Moreover, the bacteria noted in the global priority pathogens list pose a significant threat to death precisely because of their resistance to antibiotics but they currently have a very weak vaccine pipeline in terms of the number of candidates and feasibility.
The report also finds that vaccines against these pathogens are unlikely to be available in the short term and alternative interventions should be pursued urgently to prevent resistant infections due to priority bacterial pathogens, the report reads.
Dr. Haileyesus Getahun, WHO Director of AMR Global Coordination Department said that disruptive approaches are needed to enrich the pipeline and accelerate vaccine development. The lessons from COVID-19 vaccine development and mRNA vaccines offer unique opportunities to explore for development of vaccines against bacteria.
According to the report, challenges facing vaccine innovation and development include pathogens associated with hospital-acquired infections (HAI) includes difficulty in defining target population(s) among all admitted hospital patients, the cost and complexity of vaccine efficacy trials, the lack of regulatory and/or policy precedent for vaccines against HAIs.
“Vaccine development is expensive, and scientifically challenging, often with high failure rates and for successful candidates complex regulatory and manufacturing requirements require further time. We have to leverage the lessons of COVID vaccine development and speed up our search for vaccines to address AMR,” Dr. Kate O’Brien, Director of Immunization said.