Science reporter Jamie Morton explores groundbreaking research into influenza and discovers how age, ethnicity and even our pay packets may be behind the illness - and how that will effect health spending

Fever, headache, body aches, cough, extreme tiredness, watching movies on the couch and mountains of tissues - the stamp of influenza is something tens of thousands of us are all too familiar with each year.

But what does the flu have to do with our age, ethnicity or pay packets?

The relevance might surprise us, says a lead researcher of a five-year, multi-million dollar study backed by the United States' Centers for Disease Control and Prevention.

By trawling through the statistics of thousands of Aucklanders who will present at hospitals and GP clinics with flu-like symptoms this season, Dr Sue Huang, a virologist at the Institute of Environmental Science and Research, and her colleagues working under the inter-agency Shivers Project will eventually gather vital information on which Kiwis are most exposed to the flu.


The ESR-led Shivers (Southern Hemisphere Influenza, Vaccine Effectiveness, Research and Surveillance) study would also allow our limited health dollars to be spent more strategically.

The Government spends around $18 million a year on vaccines to protect the at-risk population from the flu, and employers and individuals might spend another $10 million on top of that.

Efforts to curb the cost to hospitals appear to have been working, with the cost of flu-related hospital admissions dropping from $7.3 million in 2010 to $1.5 million last financial year.

But work by the Shivers project last year found more people were hospitalised with severe acute respiratory infections caused by flu viruses than previously thought.

Researchers tracking viruses in real-time among patients admitted to Auckland and Counties Manukau hospitals last year recorded the fourth-highest rate of flu-related hospitalisations over 12 years.

Between late April and early September, there were 1370 cases of severe acute respiratory infections caused by flu viruses, including 38 intensive care unit (ICU) admissions and seven deaths.

Infants aged younger than one year had the highest influenza hospitalisation rate of 228.7 per 100,000 age group population, followed by people aged 80 and older (128.6 per 100,000), people aged 65-79 years (81.1 per 100,000) and children aged one to four years (54.9 per 100 000).

And ultimately, the research found more people were hospitalised with severe acute respiratory infections caused by flu viruses than previously thought.

Shivers results have already been used as justification by Pharmac to offer free immunisations for under-fives, who have been hospitalised or have a history of respiratory illness.

This year, Dr Huang and her team will dig deeper. Surveillance will extend past Auckland City and Middlemore Hospitals to cover 19 GP practices, where patients will be asked about their age and ethnicity, medical histories, housing situations, health access and how they caught the flu.

"People often think the flu hits developing countries, but developed countries not so much," she said.

"But the Shivers study shows the flu still hits particular populations hard - the young and people who are in the lower-socio economic group somehow have much more of a burden than people in a better socio-economic situation."

The study could act as a "fine brush" to defining which cohorts should be prioritised for assistance.

"It's become a very powerful platform to be able to assess the many different kinds of risk factors, environmental factors, clinical outcomes and management or treatment."

The study would also gauge the effectiveness of flu vaccine, whose virus strains were selected from those forecast to be circulating in 2013.

Blood samples would be taken in an effort to understand host immune response to the flu, while the differences in immune responses between hospitalised patients and those who experienced mild bouts would also be analysed.

Interest in the study's findings is not limited to our country. The United States, which awarded ESR $5 million over five years, looks to our flu season for clues to what might happen in theirs.

"They have learned they really need to look closely to the Southern Hemisphere data, and that's why they are willing to give us so much money for the study."

The Shivers Project
Q: What is it?

The Shivers Project is a collaborative five-year study led by ESR that gathers detailed information on influenza, using two hospitals and 19 GP clinics in Auckland as its survey area. The project is also designed to detect early and characterise Novel Coronavirus and potential pandemic influenza viruses such as the A(H7N9) strain which has been identified in China.

Seeing New Zealand as a useful sentinel site, the United Stateshas made a multimillion-dollar investment in the study.

Q: What does it mean for me?

Because the study breaks down its findings to specific societal groups - taking in age, income and ethnicity - the Government is better able to target who needs assistance most when it comes to flu prevention. Shivers research has already been used as justification by Pharmac to offer free immunisations for under-5s who have been hospitalised or have a history of respiratory illness.

The series
Today: The flu and us: The Shivers Project

Tomorrow: What lies beneath: Mapping our underground

Wednesday: Secrets of the ice part one: Life in Antarctica

Thursday: Secrets of the ice part two: Unlocking Antarctica's past

Friday: Our drone future: Miniature air vehicles