All vaccines, as with any medicines, can have side effects. Mild side effects, such as low-grade fever or pain and redness at the site of injection are expected and will go away on their own. Severe side effects are very rare. Getting vaccinated is much safer than getting the infections or complications that result from these infections.

Globally, vaccines are assessed by the relevant authorities to ensure they meet the required standards of quality, safety and efficacy before they are approved for use, based on the best scientific evidence available. Vaccines for use in Singapore are registered with the Health Sciences Authority (HSA). Following approval of the vaccines, their safety is still closely monitored, and any safety concerns are investigated.