If an adult with Rett Syndrome has no history of allergic reactions then it is presumed safe for them to have the currently approved Covid vaccines along with the rest of the general public.
This includes the Pfizer-BioNTech and Oxford-AstraZeneca vaccines which are licensed for use in the UK. A third vaccine from Moderna, has also been approved and will be used when stocks become available in the spring.
People sometimes think that expected reactions to a vaccine are ‘side effects’ or a ‘bad reaction.’ This includes symptoms like an increase in temperature, a sore arm, fatigue, headache, chills, joint and/or muscle pains. You can read more about the expected reactions to vaccine and allergic reactions here.
In someone who has seizures, even a slight increase in temperature can lower the seizure threshold. It’s helpful to be aware of this and take any necessary precautions to regulate temperature if possible.
If your person with Rett Syndrome has ever had an immediate allergic reaction—even if it was not severe—to a vaccine or injectable therapy for another disease, discuss with their doctor whether they should have the Covid vaccine.