What Matters in Global Health - 164

Better Use of Vaccines Could Reduce Antibiotic Use by 2.5 Billion Doses Annually, Says WHO

A new World Health Organization (WHO) report reveals that expanding vaccines targeting 24 key pathogens, the main disease-causing agents, could reduce global antibiotic consumption by 22%, equivalent to 2.5 billion fewer doses annually. Vaccines, by preventing infections before they occur, offer a proactive solution to combat the rising threat of antimicrobial resistance (AMR), which causes nearly 5 million deaths each year.

AMR develops when bacteria, viruses, fungi, and parasites evolve to resist antimicrobial medicines, making infections harder to treat. Misuse and overuse of antibiotics drive this issue, but a lack of access to necessary treatments in low-income regions compounds the problem. The WHO emphasises that vaccines can reduce the need for antibiotics and slow the emergence of drug-resistant pathogens.

While vaccines for pneumococcal pneumonia, Haemophilus influenzae type B (Hib), and typhoid are already available and could prevent 106,000 deaths annually, there is an urgent need for vaccines against tuberculosis (TB) and Klebsiella pneumoniae. These two pathogens alone could avert an additional 543,000 deaths yearly once vaccines are developed and deployed. Research into new vaccines, such as TB, is already underway.

WHO Director-General Dr. Tedros Adhanom Ghebreyesus highlighted the vital role vaccines play in the AMR fight, stating, "Prevention is better than cure, and increasing access to vaccines for critical diseases, like tuberculosis, is crucial in turning the tide on AMR."

The economic benefits of vaccines are substantial. AMR-related hospital costs exceed US$730 billion annually, and widespread vaccine use could significantly reduce these costs. Vaccines also reduce secondary infection complications, often requiring hospitalisation and antibiotic treatment.

The report evaluates 44 vaccines that could help reduce antibiotic use. For example, vaccinating 90% of the world’s children against Streptococcus pneumoniae could save 33 million antibiotic doses yearly. Accelerating the rollout of typhoid vaccines could save 45 million doses, while new vaccines for malaria and TB could save millions more.

The report builds on WHO’s ongoing efforts to address AMR and aligns with global targets set at the 79th United Nations General Assembly. These targets aim to reduce deaths related to bacterial AMR by 10% by 2030. This is a significant goal in the fight against AMR, with vaccines playing a central role.

How Far Are We From a Licensed Vaccine for the Deadly Marburg Virus?

Marburg virus, a highly lethal pathogen similar to Ebola with a mortality rate of up to 88%, has long been a cause for concern in global health. Still, unlike Ebola, no licensed vaccine exists to combat it. Rwanda, now grappling with its first outbreak of Marburg, has seen over 50 cases and 13 deaths in the span of just two weeks, sparking an urgent response from health authorities.

The World Health Organization (WHO) has identified Marburg as a top-priority pathogen, and while there are a few promising vaccine candidates, none are licensed yet. Among the candidates, the Sabin Vaccine Institute’s Marburg vaccine is the furthest along in clinical trials. Sabin Vaccine Institute’s vaccine, which uses technology previously licensed from GSK, has shown promising results in Phase 2 trials in Rwanda and other African countries like Kenya and Uganda. Following the detection of Rwanda’s outbreak, Sabin quickly delivered 700 doses of their experimental vaccine to support the country’s response. 

While this progress is encouraging, a licensed vaccine is still years away. Challenges include the need for large-scale clinical trials and the fact that Marburg outbreaks are relatively rare and unpredictable, complicating traditional efficacy trials. Sabin is exploring alternatives, such as using animal data to fast-track licensure under the U.S. FDA's "Animal Rule." However, they must also gather significant human safety data before reaching approval.

In addition to Sabin’s efforts, other organisations are advancing their own vaccine candidates. The International AIDS Vaccine Initiative (IAVI) is developing a vaccine based on technology used for MSD’s Ebola vaccine, and clinical trials are expected to begin next year. Meanwhile, the University of Oxford and other entities are pursuing different approaches, though they remain further behind in development.

Developing a Marburg vaccine faces typical obstacles, primarily affecting diseases with limited commercial potential, primarily low-income regions. Non-profit organisations like Sabin and IAVI lead the charge, often relying on public funding and partnerships to push forward. The U.S. government and other biosecurity-focused agencies have recognised Marburg as a potential bioterrorism threat, contributing significant resources to its vaccine development.

Despite these promising advances, experts warn that a licensed vaccine is likely several years away. Continued investment and international collaboration will be essential to ensure that a Marburg vaccine becomes a reality, helping to prevent future outbreaks and save lives.

WHO Approves First Mpox Diagnostic Test for Emergency Use, Boosting Global Access

In a significant advancement for global health, the World Health Organization (WHO) has approved the first mpox in vitro diagnostic (IVD) test under its Emergency Use Listing (EUL) procedure. The Alinity m MPXV assay, developed by Abbott Molecular Inc., is a real-time PCR test designed to detect monkeypox virus DNA from human skin lesion swabs, providing countries battling mpox outbreaks with a critical tool for faster, more accurate diagnosis.

The approval marks a key step in expanding diagnostic capacity, particularly in regions with limited access to testing. As of 2024, over 30,000 suspected mpox cases have been reported in Africa, with hotspots in the Democratic Republic of the Congo, Burundi, and Nigeria. Limited testing capacity in these regions has contributed to delays in case confirmation, hampering efforts to control the virus's spread. In the Democratic Republic of the Congo, only 37% of suspected cases were tested this year.

The Alinity m MPXV assay is designed for use by trained laboratory personnel, and it enables the detection of monkeypox virus DNA through nucleic acid amplification testing (NAAT), such as real-time PCR, from skin lesion samples. Early detection through this diagnostic test is expected to significantly improve mpox case management by allowing timely treatment and reducing the virus’s transmission rate.

Dr Yukiko Nakatani, WHO Assistant Director-General for Access to Medicines and Health Products, described the approval as a "significant milestone" in helping underserved countries manage the virus. WHO’s EUL procedure is pivotal in accelerating the availability of vital medical products during Public Health Emergencies of International Concern (PHEIC), as it assesses the quality, safety, and performance of products like vaccines, tests, and treatments.

The EUL listing for the Alinity m MPXV assay will remain in effect if the PHEIC related to mpox is ongoing. WHO has also received additional submissions from other manufacturers seeking EUL approval for mpox diagnostic tests to increase the quality-assured diagnostic tools available globally.

This approval provides countries, particularly in Africa, with an important resource to address the ongoing spread of mpox, ensuring quicker access to reliable diagnostics and supporting global efforts to control the virus.