Scientists have discovered how bird flu adapts in patients, offering a new way to monitor the disease and prevent a pandemic, according to research published in the August issue of the Journal of General Virology. Highly pathogenic H5N1 avian influenza virus has spread through at least 45 countries in 3 continents. Despite its ability to spread, it cannot be transmitted efficiently from human to human. This indicates it is not fully adapted to its new host species, the human. However, this new research reveals mutations in the virus that may result in a pandemic.
"The mutations needed for the emergence of a potential pandemic virus are likely to originate and be selected within infected human tissues," said Professor Dr Prasert Auewarakul from Mahidol University, Thailand. "We analyzed specific molecules called haemagglutinin on viruses derived from fatal human cases. Our results suggest new candidate mutations that may allow bird flu to adapt to humans."
Viruses with a high mutation rate such as influenza virus usually exist as a swarm of variants, each slightly different from the others. These are called H5N1 bird flu quasispecies. Professor Dr Auewarakul and his colleagues found that some mutations in the quasispecies were more frequent than others, which indicates they may be adaptive changes that make the virus more efficient at infecting humans. Most of these mutations were found in the area required for the virus to bind to the host cell.
"This study shows that the H5N1 virus is adapting each time it infects a human," said Professor Dr Auewarakul. "Such adaptations may lead to the emergence of a virus that can cause a pandemic. Our research highlights the need to control infection and transmission to humans to prevent further adaptations."
The research has provided genetic markers to help scientists monitor bird flu viruses with pandemic potential. This means they will be able to detect potentially dangerous strains and prevent a pandemic. The research also gives new insights into the mechanism of the genesis of a pandemic strain.
"Our approach could be used to screen for mutations with significant functional impact," said Professor Dr Auewarakul. "It is a new method of searching for changes in H5N1 viruses that are required for the emergence of a pandemic virus. We hope it will help us to prevent a pandemic in the future."
Source : Society for General Microbiology
Showing posts with label pandemic preparedness. Show all posts
Showing posts with label pandemic preparedness. Show all posts
Sunday, August 24, 2008
Tuesday, June 12, 2007
We're near top of killer bug table
By Anne-Marie Walsh
Saturday June 09 2007
Irish hospitals come seventh in a league table of incidents of the deadly infection across 29 countries, according to new EU figures.
The research confirms that patients are highly exposed to the hospital-based bacteria and the rate of infection has not improved since 2001.
Only six other countries, Romania, Cyprus, Malta, Portugal, the UK and Greece (in that order), have a higher rate of the antibiotic-resistant infection.
However, a spokesperson for the ECDC pointed out that the Irish figures could be misleading.
"One of the reasons that Ireland and the UK have relatively high levels of MRSA is that they are quite active in monitoring it," he said.
"Some other EU countries may not be looking as hard or monitoring it as well."
But he added: "Compared with Ireland, the Netherlands and Scandinavia have been quite successful in preventing MRSA.
The level of MRSA in Ireland has risen in the last 10 years and has levelled off."
The investigation by the EU Centre for Disease Prevention and Control (ECDC) shows that the rate of MRSA went up by 1pc in the latest available year's data.
It is at the same level it was at in 2001, and 3pc higher than the 1999 rate of 39pc, suggesting that Government initiativeson eradication have had little impact.
The ECDC warned last night that the spread of hospital-acquired infections was now the main disease threat in Europe.
It said that, if the present "rapid negative development" was not halted, mankind would soon lose one of its most important weapons against infectious disease - antibiotics.
MRSA (methicillin-resistant staphylococcus aureus) is one of the bugs in the staphylococcus aureus family of bacteria that cannot be treated with drugs.
It made up 42pc of the 1,360 detected infections in this family of bacteria in Ireland in 2005.
This represented 571 people, according to the authors of the pioneering report from the ECDC.
The rest of the cases infected with the staphylococcus aureus bacteria could be treated with drugs.
MRSA is among the forms of superbugs from the staphylococcus aureus family of bacteria that are resistant to antibiotics.
They can live on the skin and in the nose and cause a variety of illnesses including meningitis and septicaemia.
If the bacteria enters the bloodstream, it can be extremely dangerous and is potentially fatal if it belongs to the variety that is resistant to antibiotics.
The ECDC report on infectious diseases ranked countries based on the proportion of S-aureus infections found to be antibiotic-resistant.
Romania topped the table with the highest proportion of the superbug, at over 60pc.
Every year, around 3m people in the EU catch a healthcare-associated infection, of whom around 50,000 die.
One in every 10 patients admitted to hospital in the EU will catch an infection there.
"One of the biggest challenges we face is the emergence of new microbes against which our defences are weak, or even non-existent," said Markos Kyprianou, European Commissioner for Health.
"Pandemic preparedness is, and must remain, a priority for the EU."
- Anne-Marie Walsh
Saturday June 09 2007
Irish hospitals come seventh in a league table of incidents of the deadly infection across 29 countries, according to new EU figures.
The research confirms that patients are highly exposed to the hospital-based bacteria and the rate of infection has not improved since 2001.
Only six other countries, Romania, Cyprus, Malta, Portugal, the UK and Greece (in that order), have a higher rate of the antibiotic-resistant infection.
However, a spokesperson for the ECDC pointed out that the Irish figures could be misleading.
"One of the reasons that Ireland and the UK have relatively high levels of MRSA is that they are quite active in monitoring it," he said.
"Some other EU countries may not be looking as hard or monitoring it as well."
But he added: "Compared with Ireland, the Netherlands and Scandinavia have been quite successful in preventing MRSA.
The level of MRSA in Ireland has risen in the last 10 years and has levelled off."
The investigation by the EU Centre for Disease Prevention and Control (ECDC) shows that the rate of MRSA went up by 1pc in the latest available year's data.
It is at the same level it was at in 2001, and 3pc higher than the 1999 rate of 39pc, suggesting that Government initiativeson eradication have had little impact.
The ECDC warned last night that the spread of hospital-acquired infections was now the main disease threat in Europe.
It said that, if the present "rapid negative development" was not halted, mankind would soon lose one of its most important weapons against infectious disease - antibiotics.
MRSA (methicillin-resistant staphylococcus aureus) is one of the bugs in the staphylococcus aureus family of bacteria that cannot be treated with drugs.
It made up 42pc of the 1,360 detected infections in this family of bacteria in Ireland in 2005.
This represented 571 people, according to the authors of the pioneering report from the ECDC.
The rest of the cases infected with the staphylococcus aureus bacteria could be treated with drugs.
MRSA is among the forms of superbugs from the staphylococcus aureus family of bacteria that are resistant to antibiotics.
They can live on the skin and in the nose and cause a variety of illnesses including meningitis and septicaemia.
If the bacteria enters the bloodstream, it can be extremely dangerous and is potentially fatal if it belongs to the variety that is resistant to antibiotics.
The ECDC report on infectious diseases ranked countries based on the proportion of S-aureus infections found to be antibiotic-resistant.
Romania topped the table with the highest proportion of the superbug, at over 60pc.
Every year, around 3m people in the EU catch a healthcare-associated infection, of whom around 50,000 die.
One in every 10 patients admitted to hospital in the EU will catch an infection there.
"One of the biggest challenges we face is the emergence of new microbes against which our defences are weak, or even non-existent," said Markos Kyprianou, European Commissioner for Health.
"Pandemic preparedness is, and must remain, a priority for the EU."
- Anne-Marie Walsh
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