Sanofi is a leading innovator and one of the world’s largest manufacturers of vaccines. Our company is at the forefront of vaccine development across an expansive and ever-growing range of diseases.

Investing around $1 billion annually in our vaccine pipeline,we are proud that our vaccines provide protection against a wide range of severe infectious diseases while we continuously strive to develop new and improved vaccines to support public health.

This year alone, we will deliver almost 9 million doses of 15 different vaccines to help protect Australians against diseases ranging from influenza and whooping cough to meningococcal meningitis.

Sanofi works in partnership with all levels of government as well as with the medical community to ensure the value of vaccine innovation is recognised and the benefits realised for all Australians. 

How do vaccines work?

Vaccines essentially work to strengthen our immune system to protect against a viral or bacterial infection. They do this by producing an immune response, the body’s natural way of defending itself, without causing illness.2,3

Most vaccines use dead or severely weakened viruses or bacteria to train our body to recognise and fight the specific virus that causes an illness. They do not cause an infection, but our immune system still sees them as an ‘enemy’ and produces antibodies to help protect against future infection.2,3

Our immune system is likely to remember the ‘enemy’ and when exposed to that virus or bacteria in the future, will rapidly produce antibodies to destroy it.2,3

Why do we need vaccines?

Vaccination is one the most successful forms of disease prevention.4 Vaccines help protect us from many viral and bacterial infections that can cause serious illness and claim lives. Vaccination is one of the most important things we can do to protect ourselves and our children from vaccine preventable illness.5,6

However, vaccines also work at the community level. Some people can't be vaccinated, either because they are too young or because their immune system is weak. But if those around them are vaccinated, unvaccinated people benefit from something called ‘herd protection’. Put simply, because they are less likely to come in contact with the disease, they are unlikely to become sick.5,6

How are vaccines tested and approved?

All vaccines undergo rigorous safety testing before they are approved for use in Australia. During vaccine development, vaccine safety is tested in several stages. The first stage involves pre-clinical assessment in the laboratory. If a vaccine passes these safety tests, it is then evaluated in three phases of clinical trials, usually involving thousands of people.7

All vaccines available in Australia are thoroughly tested and reviewed before they are approved for use by our national medicines regulator, the Therapeutic Goods Administration (TGA). Vaccines only become available if they meet the TGA’s rigorous standards for safety, quality and efficacy.8 Once available, the TGA continues to closely monitor the safety of vaccines, along with how well they work in the community.8

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  1. Sanofi. Form 20-F 2020. Available at:
  2. Australian Department of Health. Immunisation: How does Immunisation Work? 2020/ Available at:
  3. World Health Organisation. How do Vaccines Work? Available at:
  4. Andre FE, Booy R, et al. Vaccination greatly reduces disease, disability, death and inequity worldwide. Bulletin of the World Health Organization, 2008, Bulletin of the World Health Organization, Vol. 86, pp. 81-160.
  5. Australian Department of Health. Immunisation: Why Get Immunised? 2020.
  6. UK National Health Service. Why Vaccination is Safe and Important. 2019. Available at:
  7. Australian Academy of Science. How are Vaccines Shown to be Safe? 2021. Available at:
  8. Australian Department of Health. Immunisation: Are Vaccines Safe? 2020. Available at: