CBC

Fri Nov 3, 6:46 am

Killer flu on the way

As many as 300-thousand Canadians could die when, not if a killer flu strikes this country. Health officials across the country are trying to prepare for the flu, with experts in places like Atlanta's Centre for Disease Control expecting the pandemic within the next 10 years. Alberta's deputy health officer is appealing to more disaster experts to get involved in the planning for an outbreak that will likely make 40 percent of all Canadians sick. Speaking to a disaster conference in Edmonton, Dr. Karen Grimsrud says efforts to update this country's medical disaster plans started three years ago after an outbreak of that so-called "bird flu" in Hong Kong and Alberta has been working on its own plan for the past year and-a-half. She says like other provinces, Alberta would face a crushing shortage of health care workers during a new flu outbreak that would likely overwhelm most health care systems in Canada.

-- Rachel Gibson (rgibson@hotmail.com), November 03, 2000

Answers

I just want to make clear to anyone skimming quickly through this news item: it concerns the *future* possibility of a repeat 1918- style "Spanish 'flu." The 1918 influenza epidemic ("pandemic" because it was widespread worldwide) killed far more people than World War I. The headline of this news item might suggest that such a massive influenza outbreak is being specifically predicted for the current season (2000-2001) but that's not the case. This is merely a statement on the mathematical modeling of the impact of such a pandemic, a necessary step in trying to prepare for a response by any healthcare system.

Other major epidemics of 'flu have ocurred, generally at intervals of about 11 years, but the last were in 1957 and 1968 and don't come anywhere close to the impact of the 1918 event. No one knows when such a disater might recur, but that a deadly pandemic 'flu will someday recur is accepted as a given by most people in the field, myself included.

As a related aside, a demographer has just presented a credible suggestion that the unexpected very high mortality of the 1918 influenza pandemic, especially in 20- to 40-year olds (who are not normally at high risk of death from 'flu), can be explained by high rates of tuberculosis in that age group. See the article from Population and Demographic Review at: http://demog.berkley.edu/~andrew/1918/ . If supported by other work, this paper implies that the 1918 pandemic virus was not by itself more virulent than other influenza viruses. (This is also consistent with recent laboratory data on the 1918 virus.)

Let me briefly try to explain this: It is clear that more people than usual around the globe were infected by the virus because it represented a major genetic shift by the virus, and people didn't have good immunity from prior infection with similar influenza viruses. But why the unusual death statistics? Was the virus super- strong? No, the demographer says. Rather, the virus operated on a population at greater risk of a severe outcome (i.e. death).

If true, this in turn implies--at least in the industrialized world today--that there is less risk of massive mortality among healthy adults in the prime of their lives, the most striking aspect of the 1918 experience.

"Unfortunately" there has been an increase in population size of the aged, who are indeed at greater risk of death from influenza, as are the many more people nowadays who are immunosuppressed for any reason. And tuberculosis remains a major problem in many parts of the world. So we should not be calm about the impact of a repeat 1918 'flu pandemic, even though there is alot less TB in the industrialized world today.

Anyhow, thought I'd offer you all a little perspective.

-- Andre Weltman, M.D., M.Sc., public health physician (aweltman@state.pa.us), November 03, 2000.

Thank you Andre for your perspective. It is very much appreciated that you revelled why there was so many deaths in 1918, by explaining the context of the times. This has been the hallmark of the people that frequent this forum, a desire to explain the events (potential events) in light of the context of our times.

-- Phillip Maley (maley@cnw.com), November 03, 2000.

Thanks for the great response.

-- David Williams (DAVIDWILL@prodigy.net), November 03, 2000.