Monday, August 18, 2008

Influenza's One-Two Punch

 

 

#  2237

 

 

For the past few years many scientists have subscribed to the idea that the unusually high fatality rate during the 1918 Spanish Flu was due, at least in part, to it having been a novel virus that provoked a devastatingly strident immune response in healthy victims.

 

 

This so-called `cytokine storm', where the body unleashed antibodies and cytokines at an unrecognized virus, was believed to have overwhelmed the victim and resulted in their deaths.  

 

 

This, it was felt, helped explain why young healthy adults (many in their mid-20's) fell victim to the virus.    

 

 

While the cytokine storm theory hasn't completely fallen out of favor, recent research has indicated that secondary bacterial pneumonias were one of the major factors in the high fatality rates seen in the 1918-1919 pandemic.

 

 

According to recently published research by Brundage and Shanks, 5% of the deaths attributed to the 1918 pandemic occurred in the first 3 days of infection, while the majority of them occurred after about 2 weeks.  

 

 

 

Clinical Courses of Fatal Cases Highly Variable and Often Prolonged


In most affected populations, <5% of deaths occurred within 3 days of illness onset, median time from illness onset to death was 7–10 days, and significant numbers of deaths occurred >2 weeks after initial symptoms.

 

 

This, they believe, indicates that bacterial pneumonias, and not an over active immune response, were the leading cause of death during the 1918 pandemic.

 

 

While the availability of common antibiotics far exceeds that of antivirals, today many of the common pneumonia's no longer respond to the the older tier of antibiotics.   

 

As Dr. Fauci points out, new antibiotics are needed.   But of course, that takes time.  Years, in fact.

 

 

This from the Los Angeles Times.

 

 

 

 

 

 

 

New strategy for flu pandemic

Bacterial infections killed most victims of 1918 flu, scientists say

By MARY ENGEL, Los Angeles Times
First published: Monday, August 18, 2008

 

Most deaths in the 1918 influenza pandemic were caused not by the virus alone, but by common bacterial infections that overwhelmed victims' weakened immune systems, according to two new studies that could change the strategy against the next pandemic.

 

"We have to realize that it isn't just antivirals that we need," said Dr. Anthony S. Fauci, director of the National Institute of Allergy and Infectious Diseases and co-author of one of the studies.

 

"We need to make sure that we're prepared to treat people with antibiotics," said Fauci, whose study will be released online this month by the Journal of Infectious Diseases.

 

In both studies, scientists analyzed a trove of historical documents from around the world, examining firsthand accounts, medical records and autopsy reports.

 

Writing about the 1918 influenza outbreak in the August issue of the journal Emerging Infectious Diseases, researchers reported that few of the deaths were swift.

 

Instead, they found that most of the deaths occurred a week to two weeks later -- indicating opportunistic bacterial infections.

 

Most of the samples collected from patients, dead or alive, were bacteria common to the noses and throats of healthy people, according to co-authors Dr. John F. Brundage, a medical epidemiologist at the U.S. Armed Forces Health Surveillance Center in Silver Spring, Md., and Dr. G. Dennis Shanks, director of the Australian Army Malaria Institute in Queensland, Australia.

 

So far, public health officials around the world have focused on producing and stockpiling vast quantities of antiviral drugs to combat future pandemic flu strains.

 

Fauci said scientists also need to develop new antibiotics and vaccines against bacteria, especially against a virulent strain of Staphylococcus aureus that has been linked to seasonal flu deaths worldwide and is resistant to many antibiotics.

(Continue . . .)