An interesting piece today in the New Scientist, which reaffirms something we’ve discussed often in these pages often over the past few months.
We are basically seeing two novel H1N1 pandemics going on here: a mild one, and a severe one.
For the vast majority of people – probably 99 out of 100 - this novel H1N1 virus has (thus far) produced a mild-to-moderate illness that can be usually be weathered at home.
But for an unlucky 1% (or less), this pandemic virus has produced a rapidly developing-potentially life threatening illness, requiring aggressive medical intervention and sometimes extended ventilator support.
Exactly why the vast majority of people do okay with this virus, and a select few do not, isn’t known right now. It may simply be random chance, like hitting a lottery. But there are other possibilities as well.
Some of the most severely affected victims have had underlying conditions like asthma, diabetes, or pregnancy. But reports are that 30% or more of those hospitalized were regarded to have been good health prior to infection.
Doctors and scientists are also working to determine if there could be some genetic predisposition that makes one person more susceptible to severe lung damage from this virus than another.
Most likely, it is dependent upon a host of reasons.
While less than 1% of pandemic flu patients are likely to suffer severe illness, when you have tens of millions of people infected, the number of critically ill people who will need medical resources escalates quickly.
The fear right now is, that could put hospitals and ICU’s under enormous pressures over the next few months.
While it should help put things into perspective to know that 99% of those who are infected will recover without incident, that is likely to be little solace to the 1%, and their friends and family, who do not.
- 17:01 08 September 2009 by Debora MacKenzie
Swine flu has still not grown more severe, as many feared it would but as the pandemic's second, autumn wave begins in the northern hemisphere, the virus is posing a different threat. While H1N1 mostly causes mild disease, some people – estimates suggest fewer than 1 per cent – become deathly ill, very fast.
At a meeting last week in Winnipeg, Canada, experts warned that these cases could overwhelm hospitals. "These were the sickest people I've ever seen," says Anand Kumar, an intensive care expert at the University of Manitoba in Winnipeg.
Kumar helped manage a wave of severe cases in the city in June, mostly in young Canadian aboriginals, who required the most advanced care. "This pandemic is like two diseases," he says. "Either you're off work a few days, or you go to hospital, often to the intensive care unit. There's no middle ground."
In the southern hemisphere, 15 to 33 per cent of hospitalised cases went to ICU in the past two months. "That's very high for flu," says Richard Wenzel of Virginia Commonwealth University in Richmond. "When this flu is bad, it's very bad."