Paracetamol weakens children's response to vacciantion

Paracetamol is sometimes given to infants to reduce their risk of developing fever or a fit caused by fever. In the UK, paracetamol (acetaminophen) is sold over the counter, also present in brands such as Panadol and Calpol. In the US it is more commonly available as Tylenol.

A study published in The Lancet, funded by GlaxoSmithKline Biologicals of Belgium, investigated the effect of giving paracetamol to infants during and immediate after vaccination.

459 healthy infants aged between 9 and 16 weeks were recruited from 10 centres in the Czech Republic and randomised to receive either paracetamol administered every 6 to 8 hrs during the 24 hrs following vaccination or to receive no paracetamol. The parents knew the treatment assigned to their babies.

Researchers found that in both groups, fever above 39.5 degrees C was uncommon, however lower proportion of babies in the paracetamol group had temperature above 38 degrees C. After the primary vaccine doses, more paracetamol doses had to be given to the babies in the control group than the treatment group. They also found that the antibody concentrations following the primary immunisations were significantly lower in the paracetamol group than in the control group and the response varied depending on the vaccination type given.

They concluded that "Although febrile reactions significantly decreased, prophylactic administration of antipyretic drugs at the time of vaccination should not be routinely recommended since antibody responses to several vaccine antigens were reduced."

Critics say this is an important study because there was very few published studies on this issue but further study is needed to demonstrate whether the immunity offered by flu vaccination might be reduced by paracetamol. It may be wise not to give paracetamol routinely to babies as a preventive measure.

Source: "Effect of prophylactic paracetamol administration at time of vaccination on febrile reactions and antibody responses in children: two open-label, randomised controlled trials" The Lancet 2009; 374: 1339-1350 (press release or f/t via Athens)

Study said no link between MMR and autism

The Daily Mail and other news source reported a large research, partly funded by the Department of Health and published in the Archives of Disease in Childhood, studying the blood samples of about 250 children aged 10 to 12 to see if the MMR vaccination had caused an abnormal immune response that could have triggered autism.

The sample included three groups of children : those with autism, those without and those with special educational needs. The researchers said that they found no difference in meales virus or antibody levels between the two comparison groups and no evidence of bowel symptoms among the autistic children.

The authors concluded there is no evidence for a link between MMR vaccination and autism. But critics said the study had selected the wrong children.

Source :"Measles vaccination and antibody response in autism spectrum disorders". Arch Dis Child. Published Online First: 5 February 2008 doi:10.1136/adc.2007.122937 (full text via Athens)