Keep children on vaccine schedule
By Dr. Richard Rupp and Bridget Hawkins, Ph.D.

Dear VaccineSmarts,

My 4-year-old nephew was recently diagnosed with leukemia. His mother says that he can’t have his vaccines while he’s receiving treatment.

He spends a considerable amount of time at my house with my baby and other children. Should my children still receive their vaccinations?

Jamaica Beach

Dear John,

You should inform your children’s physician of your nephew’s condition. The best thing is for them to receive their vaccines on schedule. This keeps your children from giving a vaccine-preventable disease to your nephew.

Leukemia, as well as the treatments for leukemia, can weaken the immune system. Children and adults with weakened immune systems should seek their doctor’s advice before receiving vaccines.

This is in part because the so-called “live” vaccines can sicken individuals with very weak immune systems since the virus can grow unchecked in the person’s body.

The live vaccines that children receive are the MMR (measles-mumps-rubella) and the varicella (chickenpox) vaccine. Rotavirus vaccines are also live but are given by mouth. It is not given to children with weak immune systems, although it is unlikely to cause problems.

Other vaccines are not a danger but they require a working immune system to be effective.

In general, vaccination can resume six to 12 months after completion of treatment for leukemia, as the immune system should be working well at that point.

The exception is the injected influenza vaccine, which can be given even during leukemia treatment. The rationale is that, even with a weak immune system, some protection against the flu is better than none.

The nasal influenza vaccine is not used for people with weakened immune systems because it is a live vaccine.

Vaccinating family members and close contacts to protect a vulnerable person is called cocooning. Some people worry that they can spread the live vaccine’s virus to someone with a weak immune system.

That really doesn’t happen. The exceptions are with the nasal influenza and varicella vaccines.

The nasal influenza vaccine should not be given to people who have contact with those who have a weak immune system who are hospitalized and require care in a protected environment.

In the case of the varicella vaccine, if a rash develops seven to 25 days after vaccination, the person should stay away from the immuno-suppressed individual until the rash resolves.

Hopefully your nephew was fully vaccinated before he developed leukemia so that he has some protection against these diseases. We wish your nephew a speedy and uneventful recovery.

Dr. Richard Rupp is a pediatrician and member of UTMB’s Sealy Center for Vaccine Development. Bridget Hawkins, Ph.D., is the assistant director of the Sealy Center for Vaccine Development. This column is supported by a UTMB President’s Cabinet Award to provide information about vaccines. Visit for more information.