There May be Another Epidemic

But Not as Severe as the Last

There May be Another Epidemic Of Asian Flu

The pandemic of influenza due to the Asian type of in fluenza A virus has now spread to all parts of the world, with the exception of perhaps a few islands and other isolated communities. For most areas the pandemic is over or is rapidly

decreasing.

HOWEVER, although the mortality rate has remained low, the actual number of deaths has >een by no means negligible, since n many areas a very high pro icrtion of the population has been ffected. This ranges from 20 to as ligh as 70 per cent.

Many people are now speaking nth concern about the possibilities f a “second wave” of the disease nd some fear that this might be lore severe than the first.

It may be useful, therefore, to

examines possibilities for the future.

First, it must be appreciated that every 10-15 years the influenza virus undergoes a major antigenic change, which means that people have little or no immunity to the new virus.

Since the influenza virus was dis covered in 1933 that has happened three times, the last time in 1947.

More Epidemics Forecast It is logical to expect that the Asian strain will replace the FMI group, which has been prevalent since 1947, and that it will be the predominant cause of influenza for the next decade or so.

It may also reasonably be an ticipated that epidemics of varying extent will occur every two or three years.

It may be as well to emphaise that the 1918 pandemic appears to have been an event without pre cedent in history and cannot be compared with any other pandemic of which we have record. There are grounds for believing that the Asian virus may be related to a virus pre valent in 1889 and subsequent years, since some people who lived through this period have antibodies to the Asian strain which younger persons have not.

This does not, of course, mean that what happens in 1889 and sub sequent years will necessarily repeat itself, but in view of our present lack of knowledge we must take history into account.

The 1889 pandemic did not cause a high mortality even though there were no antibiotics, and medical care was primitive compared to the pre sent day. In the two or three fol lowing years there were again ex tensive epidemics, and in some areas these were associated with a mod erate increase in mortality,

To be Watched Closely

HOWEVER unlikely it may be, we must watch carefully for any such mortality trend now.

This watch is being carried out by the WHO network of influenza centres, and many co-operating laboratories and hospitals all over world.

The network of laboratories was initiated by WHO ten years ago in

Many Pacific Territories, in common with the rest of the world, were hit by last year’s wave of Asian influenza. In this article, Dr. A. M. M. Payne „ chief of the Endemo-Epidemic Diseases Section of WHO’s Division of Communicable Diseases, discusses the newly discovered virus, and makes some predictions on what it is likely to do in the future.

anticipation of just such an event as took place last year.

Within three weeks of the first news of the epidemic reaching WHO the virus had been isolated, sent by air to the World Influenza Centre in London, identified as a new' strain and a warning issued W world-wide broadcast to health authorities that existing vaccines would be unlikely, to protect against the new virus, and that extensive spread was anticipated.

All experts agree that it is at pre sent impossible to check the spread of epidemic influenza, so that you may ask what is the use of such a warning. The first and by far the most important thing is that it gives time for the health authorities to organise medical care for the large number of people who will fall sick within a short time, and which otherwise might disorganise medical services and drug supplies.

The second purpose of the warn ing is to enable vaccine production to be initiated.

Vaccination can play a role in maintaining medical service, but it is not the major role since it is only roughly 50-70 per cent, effective and is expensive and by no means easy to produce. It is the organisa tion which matters in ensuring adequate relief for hard-hit areas.

Less Extensive

Should one anticipate a further epidemic this winter as extensive as the last? Personally, I don’t think so, although no one can be certain. A large part of the popula tion has acquired at least a basic immunity as a result of the pan oemic so it is not unreasonable to hope that if an epidemic occurs, which is not improbable since one is now under way in Japan, it will be less extensive and cause fewer complications than the pandemic Here I would stress that it may be misleading to speak of such an epidemic as a “second wave” since that carries the implication that it will be as extensive as the first. That, is, in my view, unlikely.

It would be wise to anticipate an epidemic but not a “second wave’" in the above sense.

Finally, can such an epidemic be prevented, for example, by quaran tine restrictions against countries where an epidemic is in progress?

The answer is No.