ISG warns influenza more contagious than most Australians realise 78.26 Kb

Influenza in younger at-risk groups costs Australia $130m annually, new report finds

4 April 2006 - Australian medical specialists today warned that influenza is much more contagious than many people believe; surviving in the environment for up to eight hours1 after someone with influenza coughs or sneezes.

"Influenza travels up to two metres every time an infected person coughs or sneezes and then can stay in that environment for up to eight hours, meaning that many people can become infected. Another contributing factor is the fact that infected people can be spreading the disease before they start to feel ill," said Mr Alan Hampson, Expert Advisor to the WHO and Convenor of the ISG. Influenza is highly contagious. After an infected person coughs or sneezes the virus can survive for:

• Up to an hour in the air in enclosed environments²
• More than eight hours on hard surfaces such as stainless steel and plastic¹
• Up to five minutes on hands after transfer from other surfaces¹

"There is a renewed interest in influenza following the emergence of H5N1 avian influenza, creating concern about a future human pandemic. What many people forget is that annual influenza is also very serious. In fact, in the last century more people died from annual seasonal influenza than in the three influenza pandemics, including the ‘Spanish flu'," Mr Hampson added.

Dr David Smith, Clinical Director of Microbiology and Infectious Diseases at PathWest Laboratory Medicine in Western Australia, said that there are a number of things people can do to protect themselves against influenza, whether it's a future influenza pandemic or this winter's seasonal influenza. "Vaccination is the best way of helping protect yourself against influenza. Simple measures like regular hand washing and avoiding touching your nose or mouth with unwashed hands will also protect you," Dr Smith said.

"If you become ill with influenza you can help protect others by staying at home so that you don't spread the virus, or if you have to go out ensure you cover your mouth when coughing or sneezing, and wash your hands afterwards," Dr Smith explained.

"In some situations antiviral treatments can be used to lessen the impact of infection. ‘Remedies' such as vitamin C, zinc and echinacea have not been shown to be effective in properly-conducted trials and are not recommended for preventing or treating influenza," Dr Smith added.

Dr Rod Pearce, SA GP and member of the ISG Executive, said: "It's been a few years since we had a serious influenza season in Australia, and many people tend to forget what it feels like to get the disease."

He explained that after infection even healthy young people may not be able to get out of bed for several days and not return to full health for two-three weeks. This may mean that people miss out on work, social events and also regular responsibilities such as caring for others.

"Influenza can be even more serious for people with diabetes, heart disease, a weakened immune system or a lung disease such as asthma, emphysema or chronic bronchitis," Dr Pearce added. "For these people, even if they feel fit and well, influenza can weaken their immune system and compromise their ability to manage their underlying medical condition as well as normal. This often results in hospitalisation and can even result in death."

A new report by the National Institute of Clinical Studies estimates that influenza in Australians under the age of 65 with underlying risk conditions costs the nation approximately $130m each year and generates 80,387 GP visits through illness, at a time when healthcare resources are often stretched to the limit.³

Influenza infections typically start to increase in June, peaking between July and September. However, outbreaks sometimes start earlier and it takes two weeks for full immunity to develop after vaccination.

"The ISG recommends anyone who is concerned about the impact which influenza may have on them this winter, particularly those with underlying medical conditions, to speak with their doctor about vaccination - it is the best thing that you can do to protect yourself against the disease," said Dr Pearce.

Editor's notes:

• Full copies of the National Institute of Clinical Studies' reports are available at: www.fightflu.com.au
• In addition to his role on the ISG, Mr Hampson is a consultant to the Australian Government, member of the Australian National Influenza Pandemic Action Committee and Expert Advisor to the WHO. Mr Hampson is a Consultant Virologist, and consults through Interflu Pty Ltd.

References

1. Bean B, Moore BM, Sterner B et al. Survival of influenza virus on environmental surfaces. J Infect Dis July 1982;146(1):47- 51

2. Knight V. Viruses as agents of airborne contagion [chapter V]. Annals of the New York Academic Sciences 1980;353:147- 156

3. Colgan S, Tay-Teo K, Shih S et al. NICS Evidence Report: Influenza Vaccination for ‘At-Risk' Australians Aged Between 18-64. February 2006. Found at: www.fightflu.com.au

Content Updated ( Tuesday, 04 April 2006 )