Immunisation is one of the most effective ways we protect people from infectious diseases

It’s a simple action with a lifelong impact – helping individuals stay well and supporting healthier communities overall.

This section explains what immunisation is, how vaccines work, and why they are offered at different points throughout life. It also explores the wider impact of vaccines, including how they help prevent outbreaks and protect those who cannot be vaccinated themselves.

You’ll find clear, straightforward information to help build confidence and understanding – whether you’re supporting patients, speaking with families or just want to know more yourself.

One of the most enduring and pervasive myths is the notion that vaccines, particularly the MMR (measles, mumps, and rubella) vaccine, can cause autism. This belief largely stems from a 1998 study that has since been disproved and retracted due to ethical violations and incorrect conclusions. The study’s findings were based on a very small sample size and poorly conducted research methods. Consequently, multiple studies and exhaustive research conducted globally have found no credible evidence linking vaccines to autism.

Another myth that persists is the argument that natural infection can provide stronger immunity compared to vaccinations. It is true that recovering from a disease can lead to immunity, but this can come at a significant cost. Natural infection can result in severe health complications, long term disability, or even death. For instance, complications from diseases like measles can be severe and include pneumonia, encephalitis, and even death.

Vaccines offer a safe and controlled way to develop immunity without the associated risks of contracting the actual disease. Vaccination provides protection by stimulating an immune response without causing the illness, thus delivering the benefits of immunity while avoiding the potential dangers of the diseases themselves. It is essential to consider the advantages in the context of safety and health outcomes when comparing natural immunity and vaccine acquired immunity.

Concerns often arise about vaccine ingredients, with some suggesting that vaccines contain harmful toxins like mercury or aluminium. While it is true that some vaccines contain trace amounts of these elements, they are present in quantities far below the levels we encounter daily in our environment and food supply. Moreover, these trace amounts are scientifically proven to be safe.

The use of mercury in vaccines, specifically in the form of thimerosal, has been extensively studied and found to pose no significant risk to health. Thimerosal is used as a preservative in multi-dose vials of vaccines to prevent contamination. The World Health Organization website offers detailed insights on vaccine ingredients, their purpose, and the extensive testing they undergo to ensure safety and efficacy. It provides transparency and reassurance about the rigorous standards vaccines must meet before they are approved for human use.

There is also a pervasive fear that receiving multiple vaccines could potentially overwhelm or weaken an individual’s immune system. However, the immune system is remarkably sophisticated and capable of handling thousands of antigens simultaneously. The number of antigens present in vaccines is tiny compared to what the body naturally encounters daily through our interactions with people, food, and the environment.

Health authorities develop vaccination schedules based on extensive research to ensure safety and efficacy. These schedules are designed to provide the best possible protection against diseases at times when individuals are most vulnerable. Vaccinating according to these guidelines helps protect not only the individual receiving the vaccine but also the community by contributing to herd immunity.

​​​​​​​Did you know...?

  • Vaccines are one of humanity’s greatest achievements second only to clean water
  • In the last 500 years alone, vaccines have saved almost 154 million lives. That’s six people, every minute, for five decades - nearly 94 million of the lives saved were a result of the measles vaccine
  • Vaccines for one person also keep other people safe
  • An outbreak anywhere is a threat everywhere
  • By supporting vaccinations, we are not just saving lives, but keeping deadly outbreaks from diseases such as measles, diphtheria, cholera in check all over the world
  • Responding to outbreak after outbreak is expensive and ineffective and needlessly puts lives at risk
  • Prevention – ensuring people everywhere are protected with the right vaccines, at the right time, from birth into old age
  • Vaccines save lives at all ages, protecting us throughout childhood and adulthood from upwards of 30 infections and deadly diseases
  • Since 1988, 3 billion children have been immunised against polio and 20 million people are walking today who would have been paralysed by polio
  • Vaccines create futures. A fully vaccinated child is more likely to become healthy enough to learn, grow and contribute to their community in a way that unhealthy children can’t always do
  • Since the introduction of the HPV vaccine to teenagers there has been a 90% reduction in cervical cancer rates
  • Over the last decade, the uptake of vaccines in the UK has stalled and is in many cases falling. Declining rates of routine childhood vaccination in a country with a well established universal healthcare system are extremely concerning and pose a significant public health risk, with outbreaks of preventable diseases such as measles and whooping cough already being seen
  • In between1994 and 2023 childhood vaccinations prevented 508 million hospitalisations resulting in direct savings of 540 billion and societal savings of 2 to 7 trillion
  • Global vaccine rates are currently 86% need to be 95% or above
  • Mersey Care NHS Trust have administered over 110,000 vaccinations through occupational health, school aged immunisations and seasonal vaccinations in the last 12 months (2025/26).