The Problem of AMR

Antimicrobial resistance (AMR) threatens the effective prevention and treatment of an ever-increasing range of infections caused by bacteria, parasites, viruses and fungi.

AMR occurs when bacteria, viruses, fungi or parasites change over time and no longer respond to medicines making infections harder to treat and increasing the risk of disease spread, severe illness and death. As a result, the medicines become ineffective and infections persist in the body, increasing the risk of spread to others.

Antimicrobials - including antibiotics, antivirals, antifungals and anti-parasitics - are medicines used to prevent and treat infections in humans, animals and plants. Overuse or inappropriate use of these medicines contributes to the emergence and spread of antimicrobial resistance and drug-resistant infections. The inability to treat resistant infections results in increased illness and deaths. It can also make routine medical procedures much riskier. Recent estimates suggest that almost 5 million deaths are associated with resistant bacterial infections every year ^[1].  Treating resistant infections also has economic consequences, including from increased healthcare costs, prolonged hospital stays, and time off work. 

Estimates suggest that AMR could cause 28 million people to fall into poverty worldwide due to an increase in healthcare costs of up to US$1 trillion globally by 2050 ^[2], with low-income countries expected to be the most impacted.

How do vaccines play a role in preventing AMR?

Addressing Antimicrobial Resistance starts with preventing infections.  Vaccines are therefore an important tool in the fight against antimicrobial resistance. A vaccine directly blocks the transmission of pathogens that cause infections. Decreasing this transmission decreases the  number of infections and reduces the chance of a pathogen mutating to a drug resistant form^[3].

In addition, people protected by vaccines are less likely to get sick as often, which helps reduce the overall consumption of antibiotics ^[4]. Since antibiotics are often inappropriately prescribed for viral infections, like colds and flu, vaccines against these viral infections could reduce inappropriate antibiotic use and help prevent AMR.

Vulnerable population groups and those marginalized due to ethnicity, gender, sex, and/or other factors, may suffer disproportionately from AMR due to inequities in access to care and increased risk factors for exposure to resistant infections ^[5].These population groups may also have limited access to quality health care ^[6] or to life saving antimicrobials ^[7]. Ensuring that vaccines reach these populations, especially as part of primary health care strategies, can play an important role in reducing the burden of AMR on communities and the healthcare system ^[8].

Overall, vaccines decrease the risk of both acquiring and transmitting resistant pathogens and help to reduce antibiotic use. A recent analysis suggests that vaccines can avert a large proportion of the health burden associated with AMR ^[9].This helps to protect populations, is cost-effective for health-systems, and will helps to ensure that antimicrobial medicines remain effective – now and for future generations.

Figure 1. How do vaccines help to prevent Antimicrobial resistance?

What is WHO doing to optimize the use of vaccines as tools to combat AMR?

At WHO we recognize the need to articulate the role of vaccines against AMR. As part of WHO's overall efforts to address AMR, the following work is underway to ensure vaccines are optimally utilised:

• The importance of vaccines in the fight against AMR is highlighted in the Immunization Agenda 2030: A global strategy to leave no one behind⁽¹⁰⁾.
• WHO has developed a strategy to articulate the role of vaccines against AMR, a technical annex to the Immunization Agenda 2030, and an action framework that describes a vision for vaccines to contribute fully, sustainably and equitably to the prevention and control of antimicrobial resistance by preventing infections and reducing antimicrobial use.
• WHO has analysed a pipeline of vaccines in clinical development which target the twelve priority pathogens, in addition to tuberculosis and Clostridium difficile^[10].
• WHO is carrying out work to estimate the value of vaccines in reducing AMR. This involves the development of a value attribution framework for vaccines against AMR. The framework considers the value of vaccines for 30 pathogens across five criteria:

1. vaccine averted AMR health burden,
2. vaccine averted AMR economic burden,
3. vaccine averted antibiotic use,
4. sense of urgency to develop antimicrobial approaches, and
5. pathogen impact on equity and social justice

• WHO is also engaging stakeholders in policy and decision-making at global and national levels to ensure vaccines as are optimally utilised as tools to combat AMR.