Routine childhood vaccinations should not be avoided or delayed in children with juvenile idiopathic arthritis (JIA) because of misplaced fears they may trigger flares, an Australian study has shown.
While vaccinations – along with medications and infections – have previously been proposed as a trigger for some flares in children with JIA a review of data from 138 Victorian children under the age of six found no association with any of the vaccines in the Australian National Immunisation Program.
The study, based on data derived from the Rheumatology Clinical Database at the Royal Children’s Hospital, Melbourne, found that flare activity was lower in the three months after receiving a vaccine.
Researchers from the Department of Paediatrics, Monash University, said they investigated the link between vaccination and flares in children with JIA following concerns that some doctors may be advising delaying vaccination until children are well or stable.
In their review they looked at data obtained from children with JIA between 2010 and 2016, of whom 70% were female the average age was 3.2 years and the median disease duration was 3.8 years.
Information obtained from clinic and GP records was used to compare receipt of routine immunisations with occurrence of arthritis flare as defined as specific a mention of “flare” in clinician notes, a documented increase in medication dose, or a documented increase in joint count. The vaccinations included all those in the schedule for children over the age of 12 months, including live vaccine such as MMR, and also vaccines not previously studied for flare links such as DTP, Hib, and the inactivated poliovirus vaccination.
In the six months prior to vaccination, 60% of the children were on treatment with immunosuppressive therapy such as methotrexate, NSAIDS, intra-articular steroid injections, oral prednisolone, adalimumab and etanercept.
During the 90 days following immunisation, children were about 40% less likely to experience arthritis flares than during a self control ‘baseline’ period before vaccination (relative risk 0.59).
The researchers said their findings complemented those of previous studies that had found little evidence of flares following vaccination – although they noted that previous research had involved only small numbers of children and had not covered all the vaccines used in Australia’s childhood immunisation schedule
They said the results should provide reassurance to families and health professionals about the safety of routine childhood vaccinations in children with JIA.
“These findings should encourage clinicians and families to vaccinate children even the setting of the COVID19 pandemic. Outside of the immunisation encounter, vaccination will not increase risk of flares or healthcare system interaction,” they wrote in the International Journal of Rheumatology.
However they acknowledged that the flare risk following rotavirus vaccination, which is only administered in infancy, could not be analysed in their study. They said they only included children over 12 months of age, consistent with the age of onset of JIA.
Meanwhile, in newly released advice on vaccines and arthritic conditions for patients, the Australian Rheumatology Association notes that rotavirus vaccine is the only live vaccine routinely given to babies less than 12 months old.
The ARA advises that rotavirus vaccine is probably best avoided in babies less than six months old born to mothers taking biologics during pregnancy and breast-feeding, as most (with the exception of certolizumab) will cross the placenta and also enter breast milk. Live vaccines should be delayed until the baby is weaned, the ARA advises.