VOA常速英语:Doctors, Researchers on Lookout for New Flu Outbreak

Within the past 10 years, two serious pandemics have raised public health alarms around the world. The first was a respiratory infection known as SARS; the second, a virulent swine flu virus known as H1N1. Isolated cases of H1N1 continue to crop up. And as concerns grow about other potential threats, including the H5N1 or avian flu virus, international health officials are taking precautions to prevent any new pandemics.

The H1N1 influenza virus infected about 61 million people during the 2009 pandemic. Dave Cornwell was one of them. “I had a fever, I was achy, you know, flu-like symptoms," he described. "And while I was in the emergency room for several hours, someone finally came in and said it looks like piggy flu.”

H1N1 -- also known as swine flu -- claimed about 18,000 lives worldwide. What began in April 2009 in North America quickly spread around the world. Seven years earlier, it was an epidemic of Severe Acute Respiratory Syndrome, or SARS, which originated in Southeast Asia.

"There were about 8,000 cases of SARS in 2002-3, although it was severe but not extensive. And H1N1 wasn’t severe but very widespread around the world," said Dr. Kevin De Cock. He is the director of the Center for Global Health at the Centers for Disease Control and Prevention in Atlanta, Georgia.

“We can’t always depend on severity and extent of spread being separated like that. We are prepared, but there is still a lot of work to be done," De Cock stated. "We cannot take anything for granted.”

Dr. Isabelle Nuttall is a top World Health Organization official in Geneva. She says a lot of progress has been made... in preparing for another epidemic, but not nearly enough, despite commitments to be ready for a serious outbreak by 2012.

"Countries committed to work to implement surveillance systems, to be able to have good laboratories in place, to be able to report and inform their population, containment measures if need be, to be able to stop the spread of diseases," said Nuttall. "I do realize it’s a lot of work but we are not there yet.”

Outbreaks are common around the world. Dr. De Cock at the CDC says people should be vigilant, but not unduly worried, and he points to H5N1 virus, or avian influenza, as an example. “It seems not to be transmissible from person to person; nonetheless, infectious diseases can change in their epidemiology," he explained.

Earlier this year, an outbreak of influenza in Mexico prompted people to line up en masse to get vaccinated. Ninety percent of the reported 1,600 cases of flu were from the H1N1 strain, which has also been on the upsurge in northwestern India.

WHO has set up the Global Outbreak Alert and Response Network, and, at its Geneva headquarters, a Strategic Health Operation Center. In this high-tech facility, experts from all medical fields regularly gather to monitor and analyze the latest data on global disease outbreaks -- ready to act at the first sign of the next epidemic.