Waikato has seen a dramatic decline in the potentially deadly Rotavirus disease since the free immunisation was introduced in July 2014.
Immunologists are expecting a similar downward trend to follow throughout New Zealand, which is hoped to reduce the burden on families and communities from a disease that can lead to severe dehydration and other complications.
Rotavirus is a significant cause of hospitalisation from gastroenteritis in infants and children.
“High rates of hospitalisation from rotavirus appear to be a thing of the past,” said Waikato District Health Board paediatrician Dr Dave Graham.
Data on the rotavirus decline in Waikato is just one of the papers to be presented at the New Zealand Immunisation conference on Saturday, September 5.
The conference also will present results on the effectiveness of this year’s trivalent influenza vaccine in NZ.
The SHIVERS (Southern Hemisphere Influenza and Vaccine Effectiveness Research and Surveillance) study has monitored the impact of hospitalisations from influenza-like-illness since 2012 and those with influenza-like-illness seen in primary care (sentinel general practices) since 2013.
Dr Sue Huang from the Institute of Environmental Science and Research (ESR), principal investigator for the SHIVERS study said the data helps to inform planning for the Northern Hemisphere’s winter influenza season.
“The preliminary 2015 season data has shown that the predominant circulating influenza viruses were covered in the influenza vaccine formulation for NZ’s winter time.”
Pertussis (whooping cough) continues to severely affect young infants, with significant outbreaks every few years. The conference will hear from a range of speakers looking at aspects of this disease.
One important study has examined the effectiveness of the current NZ immunisation schedule to prevent pertussis disease and the results will be presented on Friday, September 4.
“We know that immunity gained from the current pertussis vaccine doesn’t last as long as we would like”, explains Dr Sarah Radke, epidemiologist from the Immunisation Advisory Centre, “understanding how long the protection lasts in real terms is important work. It was reassuring to find that, following the primary 3-dose vaccine course completed at five months of age, protection against severe disease is sustained through to children’s fourth birthdays. We have shown that protection from the infant course lasts through the early years – reaffirming that the current immunisation schedule with a booster at age four years is working effectively for NZ.”
One of the most effective ways to protect those under five months of age from pertussis is maternal vaccination, with the mothers passing protection to their infants in utero, offering important protection for the early months, prior to the infant receiving their own vaccinations.
Vaccination in pregnancy has been funded since 2013, however, the uptake of maternal vaccination remains low. A study in Canterbury DHB looked at the reasons behind a mother’s decisions to be immunised or not.
“Our study clearly shows the importance of making sure mothers receive accurate and timely information to assist in their decision”, says Linda Hill, lead author of the study. “It is apparent that not all mothers were aware that the antenatal vaccination was freely available, and in some cases had received discouraging information regarding the recommended maternal pertussis-containing vaccine.”
The conference’s international keynote speaker, Canadian Prof. Noni MacDonald understands the challenges around communicating immunisation issues well.
“Vaccine hesitancy is a global problem, it is very complex however- varying across time, place and vaccines and influenced by factors such confidence, complacency and convenience. There are strategies at both a programme and individual level that can help mitigate hesitancy.”
With New Zealand’s increasing rate of immunisation coverage and resultant lower disease rate, it is easy to forget that some diseases are still common for our wider Pacific and Asian neighbours. Dr Mark Jacobs, director, Communicable Diseases from the WHO’s Western Pacific Regional Office, will provide a progress update on the region’s vaccination programme goals, including the elimination of measles – a status achieved in Australia, but not yet in New Zealand.
Theo Brandt: Communications Manager, The Immunisation Advisory Centre 021 376 478
Dr Helen Petousis-Harris, Director of Research, The Immunisation Advisory Centre 0274 716 749
Dr Nikki Turner, Director, The Immunisation Advisory Centre 021 790 693