Australian study: Rotavirus vaccine increases the risk of intussusception, but benefits of vaccine outweigh risks

Both of the currently available rotavirus vaccines in Australia are associated with a small increase in the risk of intussusception in young infants, according to new research by the Institute and the National Centre for Immunisation Research & Surveillance, Sydney.

Intussusception occurs when one portion of the bowel slides into the next, much like the pieces of a telescope. This, in turn leads to swelling, inflammation, and decreased blood flow to the part of the intestines involved and can create a blockage in the bowel. In countries such as Australia, intussusception is usually diagnosed within 24 hours and promptly treated with a good outcome. No infant deaths from intussusception have occurred in over 10 years.

Rotavirus is the leading cause of gastroenteritis worldwide. In 2007, two oral rotavirus vaccines, Rotarix and RotaTeq, were licenced and included for free in the National Immunisation Program in Australia. Before vaccines were available, rotavirus "gastro" in young babies often resulted in vomiting and diarrhoea severe enough to require hospitalisation, sometimes with complications and even death (approximately one death each year).

In the study, researchers looked at the intussusception cases in children between one and 12 months of age in all states over a four year period between 2007 and 2010. The vaccination history for each case was obtained from the Australian Childhood Immunisation Register (ACIR) to determine which rotavirus the child received and when. This allowed calculation of whether the chance of developing intussusception was higher soon after receiving a vaccine compared with before vaccination or later.

The study found there was a slightly greater chance of developing intussusception soon after receiving either rotavirus vaccine. This suggests that vaccinating babies in Australia would result in approximately 14 extra cases of intussusception per year, from about 144 cases to 158 across Australia annually. On the other hand, rotavirus vaccines were conservatively estimated to prevent 6500 hospitalisations due to acute gastroenteritis per year in Australia among children less than five years of age.

"We found a similarly increased risk of intussusception following both Rotarix and RotaTeq vaccines in Australia. However, despite a small increased risk of intussusception associated with both vaccines, the benefits of rotavirus vaccination in preventing rotavirus gastroenteritis clearly outweigh the risks," lead researcher, Dr Katherine Lee said.

In Australia, hospitalisation rates for rotavirus have dropped by over 70 per cent since vaccine introduction in 2007. Other less developed countries have even more hospitalisations and deaths from rotavirus than Australia - many are already using these vaccines, with other countries currently considering rotavirus vaccination.

"Although countries planning to implement rotavirus vaccines into their national immunisation program will need to consider their rotavirus disease burden in relation to the incidence of and ability to diagnose and treat intussusception, it seems likely that the benefits of these vaccines will outweigh the risks in other settings too," Dr Lee said.

The Australian Technical Advisory Group on Immunisation (ATAGI) continues to recommend that rotavirus vaccines should be given to babies under the Australian National Immunisation Program. Intussusception is a rare condition and is associated with regular bouts of abdominal pain that may involve crying, distress and drawing up of the legs - parents should take their baby to be examined by their doctor if they have concerns. More advice on vaccination and intussusception as a side effect is available on the Immunise Australia website: www.immunise.health.gov.au.

This is an internationally significant study documenting evidence of an important though rare side-effect of these vaccinations. It provides an excellent example of the value of public health surveillance and epidemiological research in precisely identifying the effects (both positive although occasionally negative) of vaccination.

add to favorites email to friend print save as pdf

Related Stories

Engineered rice protects against rotavirus infection

Aug 08, 2013

For children and immune compromised adults in developing countries, diarrheal disease induced by rotavirus can be life threatening. Current rotaviral vaccines are highly effective in the Western world, but are not as effective ...

Rotavirus vaccine given to newborns in Africa is effective

Jun 17, 2013

Mayo Clinic and other researchers have shown that a vaccine given to newborns is at least 60 percent effective against rotavirus in Ghana. Rotavirus causes fever, vomiting and diarrhea, which in infants can cause severe dehydration. ...

Recommended for you

Spain: Ebola test drug out of supply worldwide

42 minutes ago

Doctors treating a Spanish priest who was repatriated from West Africa on Monday after being diagnosed with the Ebola virus said there were no samples of experimental drug ZMapp available in the world right ...

A multiscale approach to Ebola response

2 hours ago

The Ebola outbreak in western Africa continues to spread uncontrolled, affecting thus far five countries. On September 16th, President Obama spoke at the Centers for Disease Control and Prevention headquarters ...

Overwhelmed west Africa ramps up Ebola response

17 hours ago

West Africa intensified its response to the deadly Ebola epidemic on Sunday, with Sierra Leone uncovering scores of dead bodies during a 72-hour shutdown and Liberia announcing hundreds of new hospital beds.

Sierra Leone reaches final day of Ebola lockdown

20 hours ago

Frustrated residents complained of food shortages in some neighborhoods of Sierra Leone's capital on Sunday as the country reached the third and final day of a sweeping, unprecedented lockdown designed to ...

User comments