How Vaccines and Antibiotics Are Emerging as Powerful Weapons Against Certain Cancers

**Lead**

A quiet revolution is under way in oncology, as vaccines and antibiotics — long the mainstays of infectious disease control — are increasingly being deployed to prevent, treat, and even beat certain cancers. In the United Kingdom, where the NHS has already rolled out the world’s first national HPV vaccination programme for boys and girls, the concept of using the body’s own immune system to fight malignancies is no longer theoretical. Researchers are now exploring how existing vaccines, such as the BCG jab for tuberculosis, can stimulate an immune response against bladder cancer, while antibiotics are being studied for their ability to disrupt the microbial ecosystems that fuel tumour growth.

**Context**

The link between infection and cancer is not new. The World Health Organisation estimates that roughly one in six cancers worldwide is caused by infectious agents, including viruses, bacteria, and parasites. In the UK, the human papillomavirus (HPV) is responsible for nearly all cases of cervical cancer, as well as a growing proportion of head and neck cancers. The NHS HPV vaccination programme, introduced in 2008 for girls and extended to boys in 2019, has already led to a dramatic reduction in cervical cancer rates among young women. Similarly, the hepatitis B vaccine, which prevents a virus that can lead to liver cancer, is part of routine childhood immunisation in many countries.

Beyond prevention, therapeutic vaccines are being developed to treat existing cancers. The most established example in the UK is the BCG vaccine, which is instilled directly into the bladder for patients with non-muscle invasive bladder cancer. This treatment has been used for decades and works by triggering a localised immune response that attacks tumour cells. More recently, oncolytic virus therapies — genetically modified viruses that selectively infect and destroy cancer cells — have gained regulatory approval. The first such therapy, T-VEC (talimogene laherparepvec), is licensed in the UK for advanced melanoma and uses a modified herpes simplex virus.

Antibiotics, too, are entering the cancer conversation. The bacterium Helicobacter pylori is a known cause of stomach cancer, and eradicating it with a course of antibiotics can reduce the risk of developing the disease. Meanwhile, a growing body of research suggests that the gut microbiome — the trillions of bacteria living in the digestive tract — plays a critical role in how patients respond to immunotherapy. Certain antibiotics, when used judiciously, may help rebalance the microbiome and improve the efficacy of checkpoint inhibitors, drugs that unleash the immune system against tumours.

**Analysis**

The implications for the UK are significant. The NHS Long Term Plan has already committed to expanding cancer prevention and early diagnosis, and the repurposing of existing vaccines and antibiotics offers a cost-effective way to accelerate progress. Unlike many novel cancer drugs, which can cost tens of thousands of pounds per patient per year, vaccines and antibiotics are relatively inexpensive and have well-understood safety profiles. This makes them particularly attractive for use in the NHS, where budgets are constrained and the demand for cancer care is rising.

However, experts caution that the approach is not a universal cure. Vaccines work best against cancers caused by specific infectious agents, and therapeutic vaccines have so far shown limited success against established solid tumours. Antibiotics, meanwhile, must be used with care to avoid contributing to antimicrobial resistance, a growing public health threat. Researchers at the Francis Crick Institute and the University of Oxford are leading trials to identify which patients are most likely to benefit from microbiome modulation, and to develop next-generation vaccines that can target a wider range of cancer types.

The technology behind these treatments is advancing rapidly. Advances in genomics and bioinformatics now allow scientists to design personalised cancer vaccines that target the unique mutations in a patient’s tumour. Early-phase trials in the UK, including those run by the Cancer Research UK–funded centres, have shown promising results in melanoma and lung cancer. Similarly, new classes of antibiotics that specifically target cancer-associated bacteria without harming the rest of the microbiome are being developed in laboratories across the country.

**Fontes**

- NHS England: HPV vaccination programme data and BCG treatment guidelines. - Cancer Research UK: information on infection-related cancers and vaccine research. - The Lancet Oncology: recent studies on gut microbiome and immunotherapy response. - National Institute for Health and Care Excellence (NICE): guidance on T-VEC for melanoma. - Francis Crick Institute: ongoing research into oncolytic viruses and microbiome modulation.