NZ children hospitalised with chickenpox face ongoing complications – study

Kiwi children are needing to be hospitalised, with nearly one in ten of those hospitalised ending up in intensive care, and many face serious ongoing health complications as a result of contracting chickenpox, according to a new study1.

The research, led by Starship Children’s Hospital infectious disease specialist Dr Sophie Wen, found 144 children were admitted to hospital in just two years with disease caused by the varicella zoster virus (commonly called chickenpox).

Of those children, almost one in 10 needed to be treated in the intensive care unit, despite the majority being previously healthy.

It also found that almost a third of children who needed to be hospitalised suffered multiple complications from the disease, including neurological complications, which led to ongoing health issues in nearly 20% of them after being discharged.

The study, which looked at data collected from 2011-2013 and was published in June this year, aimed to document the hospital burden of chickenpox - a common childhood disease in New Zealand.

It acknowledged earlier findings that demonstrated the risk of serious complications and death from the disease, which is often considered a mild infection by parents.

Findings from the study also reconfirmed that Maori and Pacific Island children are over-represented, with an almost three- and four-fold increase in risk of hospitalisation, respectively.

The study authors also found that "the perception of varicella always being a benign childhood disease needs to be re-dressed” in New Zealand in light of the findings.

They also noted the hospitalisation costs were only a small part of the monetary issues associated with chickenpox, citing that the “indirect costs of parent absenteeism and loss of associated productivity have been reported to range from 42% to 98% in the total cost of varicella”.

Dr John Cameron, a GP with 35 years of experience, says there is often a complacent attitude among New Zealanders about the disease. “Parents think, ‘We all had it, so the kids will have it as well’,” says Dr Cameron. “It’s often seen as a normal consequence of childhood.”

However, Dr Cameron says that is no longer an acceptable attitude with a vaccine now available. “It’s now a preventable disease, and people need to be aware of the dangers associated with chickenpox infection, as well as the fact it is now a preventable illness,” he says.

“It makes kids utterly miserable, and it can lead to hospitalisation, as this research shows. Hospitalisation is a significant serious event for not only a child but also for their family. Most young children never need to go to a hospital, but being admitted can place a tremendous strain on families,” he explains.

“Also, hospitals are actually not very healthy places to be in, so we do try to keep people out of them as much as possible, especially young people,” he says. “And if your child suffers even more serious, ongoing complications from chickenpox that can be catastrophic for a family.”

Dr Cameron says he believes most GPs would like to see the varicella vaccination included on the immunisation schedule for all children “as it is in many other countries”, but in the meantime there is a need to address a disparity in access for those who need it most, including the Maori and Pacific Island communities.

“There is some research to suggest those communities are less able to self-fund the vaccination, which currently costs around $75 - a significant amount of money for many families.”

Immunisation Facilitator, Helen Ride, agrees that Kiwis need to be aware of the dangers of chickenpox and says it's time chickenpox wasn't dismissed simply as a childhood rite of passage.

“It is often perceived as a very mild illness and I still hear of chickenpox parties,” she says. “What some members of the community are not aware of is that chickenpox can be a serious disease with serious complications resulting in hospitalisation and ongoing health problems for the affected person.”

She also points out that the financial cost for families can be high. “Something which many people would not consider is the financial burden your child having chickenpox can have on the family.

“Even in a mild case, the child will be excluded from daycare or school and will require a parent to stay home and care for the child. If a number of children in the household are susceptible to chickenpox then this can equate to over four weeks home caring for infected children.”

The Pinnacle Midlands Health Network worker says the safest way to mitigate the effects of chickenpox on your family is to vaccinate your children and any adults not immune to chickenpox.

Vaccination for chickenpox is currently only funded for high risk populations in New Zealand, however it is used in 96 countries around the world, including in funded programmes in nations such as Australia, the United States, and Germany2-5.

It is recommended for all children by the NZ Ministry of Health Handbook6 and the Immunisation Advisory Centre (IMAC)7, and researchers for the latest study concluded “universal vaccination is the only effective strategy in preventing severe complications and death”.

Parents are encouraged to discuss their options for vaccination with their primary healthcare provider once their child is five months old, with children able to be protected against chickenpox from nine months of age.


  1. Wen SC et al. J Paediatr Child Health. 2015; DOI: 10.1111/jpc.12937
  2. GSK Varilrix® data on file
  3. Siedler, A. and U. Arndt. Euro Surveill, 2010. 15(13)
  4. Davis, M.M. et al. Pediatrics, 2004. 114(3): p. 786-92
  5. Carville K.S. et al. Vaccine. 2010;28:2532-8
  6. Ministry of Health. Immunisation Handbook 2014. Wellington: Ministry of Health; 2014
  7. Immunisation Advisory Centre (IMAC). Vaccines and Vaccination. Accessed 3 November 2015
  8. Takahashi M. Paediatri Drugs. 2001;3:285-9 

Notes to Editors:

There are two brands of chickenpox vaccine available in New Zealand. GSK are makers of Varilrix® (varicella-zoster vaccine) which was first licensed for use in 1994. The chickenpox vaccine has been shown to provide at least 20 years of protection. The chickenpox vaccine has been shown to provide at least 20 years of protection.8

Enquiries or interview requests please contact:

Kim O'Donohue
Phone: +61 477 322 431

GSK – one of the world’s leading research-based pharmaceutical and healthcare companies – is committed to improving the quality of human life by enabling people to do more, feel better and live longer. For further information please visit or