Researchers said the cholera bacterium today is more deadly than its previous types, urging that vaccines should be considered even after an outbreak starts, according to media reports Friday.
Some Haitian are seen at a cholera treatment center of Medecins Sans Frontieres MSF (Doctors Without Borders) in Port-au-Prince Jan. 15, 2011. (Xinhua File Photo)
In a package of studies reported in the journal Public Library of Science (PLoS), researchers noted that a hybrid strain of cholera underwent two major changes in the last 20 years, causing longer outbreaks of the disease with increased fatalities.
The first mutation resulted in the bacterium infecting patients thought to be immune because of previous exposure to an older strain. The second made it more dangerous, according to Edward Ryan, a researcher at Massachusetts General Hospital and Harvard University in the United States.
"Cholera caused by the hybrid strain may be more clinically severe and ... may explain why we are seeing case fatality rates of 1 to 5 percent in recent outbreaks as opposed to under 1 percent historically accepted as the goal for response teams," Ryan wrote in an editorial.
Authors of the studies said mass vaccinations should be considered as a solution even after outbreaks have begun.
Experts have differed over the usefulness of cholera vaccine once an outbreak has occurred. Many experts agreed taht resources in an outbreak should focus on rehydrating the sick and providing safe water and improved sanitation.
The debate has been reignited by a recent epidemic in Haiti, where more than 2,000 died of cholera and at least 105,000 people fell ill in the cholera epidemic that followed an earthquake killing more than 250,000 in January 2010.
VietNamNet/Xinhuanet
