Vaccines such as the combined measles-mumps-rubella (MMR) shot and the vaccine against the chicken pox varicella-zoster virus (VZV) are safe and generate a good immune response in children with liver and/or kidney transplants, shows research led by the Children’s Hospital Colorado.
“This shifts the paradigm of the approach to protecting this vulnerable population where live viral vaccines were previously avoided,” said senior study investigator Lara Danziger-Isakov, interim director of the Division of Infectious Diseases at Cincinnati Children’s Hospital, in a press statement.
“This should enable children who have received organ transplants to integrate into their communities with more confidence and decreased risk for acquiring chicken pox or measles, which have both made a resurgence.”
The clinical trial included 281 children who had received liver transplants (n=270), kidney transplants (n=9) or liver and kidney transplants (n=2).
The children received between one and three doses of the MMR vaccine and/or VZV vaccine several years after receiving their transplanted organs between 5 and 15 years of age. Most of the children (73%) were receiving immunosuppression therapy when they were vaccinated.
As reported in the journal JAMA Network Open, the majority of the children (72% varicella, 86% measles, 83% mumps, 99% rubella) who were vaccinated produced antibodies against the diseases being vaccinated against. This immune protection was maintained at one year in the majority of the children in the study.
Live vaccination has been largely avoided in transplant recipients in the past due to worries about infection with the viruses in the vaccine or other side effects such as transplant rejection.
In this study, there were five cases of chicken pox after vaccination in children receiving medium to high levels of immune suppression therapy at the time, which resolved in all children within a week. There were no cases of measles or rubella and no confirmed cases of mumps (there was one suspected case, but this resolved quickly without treatment) within one month of vaccination. None of the children experienced organ rejection linked to the study.
“Community acquisition of measles and varicella is a real risk for immunocompromised children in today’s world,” said senior author Amy Feldman, medical director of the Liver Transplant Program at Children’s Hospital Colorado.
“These infections can be fatal in transplant recipients. Being able to administer live vaccines post-transplant, and provide immunity, is critical.”
The researchers now plan to confirm their findings and continue to monitor the children in the study to assess how long their immunity to these diseases is maintained compared with non-immunocompromised individuals.