Herd immunity occurs when enough people become immune to a disease, either through vaccination or previous infection. This can reduce the likelihood of it spreading and increase protection for vulnerable groups.

Herd immunity refers to the indirect protection from a disease that occurs when a population achieves immunity either through vaccination or previous infection.

It’s important to note that the World Health Organization (WHO) recommends vaccines as the safest and most effective way to achieve herd immunity. Vaccinations can help reduce the risk of dangerous and preventable diseases and help ensure that already eliminated diseases stay under control.

Learn more about what herd immunity is, the risks of missing or delaying vaccination, and how you can make the right choice for you or your child.

Herd immunity, also known as ‘herd protection,’ refers to when a significant percentage of the population has developed immunity to a disease, reducing the chance of it spreading.

It can occur in two key ways, either through vaccination or previous infection.

  • Natural immunity: When your body is exposed to a pathogen, such as a virus or bacterium, it uses immune cells to fight it off. It also creates memory cells that learn and remember pathogens, ensuring you can fight off any future infections.
  • Vaccine-induced immunity: Vaccines safely expose the body to parts of the pathogen, mimicking a response to an infection. This enables the body to train its immune system to recognize and combat the pathogen in the event of future infections.

While both methods can lead to herd immunity, the WHO recommends vaccines as the safest and most effective way to reduce disease risk and save lives.

Myth vs fact: Herd immunity

Myth: My child doesn’t need to be vaccinated because other children are already vaccinated and immune.

Fact: Herd immunity can only occur if enough of the population is vaccinated. Relying on others getting vaccinated as protection can create a dangerous concept where fewer people develop immunity, leading to diseases spreading more quickly.

Remember, herd immunity is not a substitute for getting vaccinated.

Delaying or refusing vaccination can increase your risk of developing dangerous and preventable diseases, such as tetanus, polio, and measles. This can cause long-term complications that can lead to potential hospitalization, such as damage to your lungs and heart. In severe cases, these complications can be fatal.

Low vaccination rates can also impact herd immunity by allowing diseases to spread more easily, which can create a higher risk for vulnerable groups who cannot be vaccinated.

When a higher percentage of the population remains unvaccinated, it can overwhelm healthcare systems and place additional strain on medical staff and resources, resulting in delayed care for everyone.

Can viral diseases considered eradicated come back?

When people don’t get vaccinated, previously eradicated diseases can come back.

For example, measles was declared eliminated in the U.S. in 2000. This was due to a significantly high percentage of people receiving the measles, mumps, and rubella (MMR) vaccine. However, over the past few years, MMR vaccination rates have declined, particularly among children, resulting in new outbreaks of measles.

Maintaining high vaccination rates is crucial for preventing future outbreaks of diseases that have been eradicated.

If you are unsure about whether you should get vaccinated, it can be helpful to have an open and honest conversation with a doctor. They can provide you with the accurate information needed to help you make an informed decision.

Remember, a good doctor will listen to your concerns without judgment and provide clear guidance.

Here are some questions you can ask a doctor, to help you decide:

  • What are the benefits of getting this vaccine?
  • How effective is this vaccine, and how long will it protect me?
  • Are there any side effects I should be aware of?
  • Are there any ingredients in this vaccine that may be harmful?
  • Is this vaccine safe for people with my health conditions?
  • Has this vaccine been tested on people with similar health conditions to mine?
  • How is this vaccine monitored for safety?
  • What should I do if I experience a negative reaction after receiving the vaccine?

Tips for parents and caregivers

If you are unsure about vaccinating your child, the following questions can be helpful to ask a pediatrician:

  • What vaccines does my child currently need?
  • Can we space out their vaccination schedule? Are there any risks to doing this?
  • How will these vaccines keep my child safe?
  • Are there any potential side effects and how rare are they?
  • How safe are these vaccines for my child’s health conditions and allergies?
  • What should I look out for after vaccinating my child?
  • If I have any concerns after vaccinating my child, who can I speak to?

How to spot vaccine misinformation

Vaccine misinformation can spread quickly, both online and offline. Remember, the information you hear about vaccines may not always be based on scientific evidence.

To identify vaccine misinformation, it can be helpful to look out for stories and claims that:

  • are not from credible sources
  • use sensationalised or overly emotional language, such as promises of miracle cures
  • use fear-based claims rather than scientific evidence

If in doubt, a healthcare professional can help dispel any medical misinformation you come across and point you toward trusted sources.

Herd immunity occurs when enough people become immune to a disease, either through vaccination or previous infection.

While both methods can lead to herd immunity, the WHO recommends vaccines as the safest and most effective way to reduce disease risk and save lives.

Maintaining high vaccination rates is crucial for reducing the risk of dangerous and preventable diseases and helping ensure that already eradicated diseases stay under control.