Treyfish
Moderator
By Jason Gale
Aug. 31 (Bloomberg) -- An American tourist in China spread swine flu while talking to fellow bus passengers at close range, suggesting that virus-laden droplets expelled from the mouth are a key mode of transmission, scientists found.
The 40-year-old woman who traveled in early June from New York to Jiuzhaigou, a popular tourist spot in southwestern China, probably sparked an outbreak among 30 members of her holiday group, the researchers said in a study in the October edition of the journal Emerging Infectious Diseases.
The woman developed symptoms about a day after leaving the U.S. and spent almost 7 hours riding with the group on an air- conditioned bus. Those who chatted with her for at least 10 minutes within a 2-meter (6.6-foot) range, regardless of their seat or other forms of social contact, had a greater risk of infection, the authors said. The finding suggests preventing transmission by droplets may foil the spread of the pandemic bug.
?Our data show that this outbreak was caused by talking with the index case-patient at close range, which indicates droplet transmission,? wrote Ke Han, a researcher with the Chinese Center for Disease Control and Prevention in Beijing, and colleagues. ?Conversely, other kinds of contact, such as dining at the same table and receiving chewing gum from the index case-patient, played no role during this outbreak.?
The researchers, who included officials from provincial disease-control centers, studied the outbreak to identify the source of infection, mode of transmission and risk factors.
?Distinctive Hairstyle?
The index case had ?a highly distinctive hairstyle, which made her easy to remember,? the authors wrote.
Nine of the 16 tourists who spoke with the infected woman, or index case, at close range for 2 minutes or more caught the new H1N1 influenza virus, whereas none of the 14 tourists who didn?t talk to her became ill, according to the study.
Tour group members who talked to the woman for at least 10 minutes were almost five times as likely to become ill than those who spoke with her for 2 to 9 minutes, they said.
During this outbreak, the woman had a fever while traveling on three flights, and a person who subsequently became infected also flew while feverish, they said. A third patient caught a flight while suffering from a headache.
The fevers weren?t detected by thermal scanning at airports, according to the study. All three passengers didn?t truthfully inform health authorities of their symptoms in health questionnaires they were required to complete, the report said.
?These data suggest that thermal scanning and health questionnaires at the airports were not effective for detecting pandemic (H1N1) 2009 infections,? the authors said. :tiphat:http://www.bloomberg.com/apps/news?pid=20601080&sid=aUPeH8T6FYgg
Aug. 31 (Bloomberg) -- An American tourist in China spread swine flu while talking to fellow bus passengers at close range, suggesting that virus-laden droplets expelled from the mouth are a key mode of transmission, scientists found.
The 40-year-old woman who traveled in early June from New York to Jiuzhaigou, a popular tourist spot in southwestern China, probably sparked an outbreak among 30 members of her holiday group, the researchers said in a study in the October edition of the journal Emerging Infectious Diseases.
The woman developed symptoms about a day after leaving the U.S. and spent almost 7 hours riding with the group on an air- conditioned bus. Those who chatted with her for at least 10 minutes within a 2-meter (6.6-foot) range, regardless of their seat or other forms of social contact, had a greater risk of infection, the authors said. The finding suggests preventing transmission by droplets may foil the spread of the pandemic bug.
?Our data show that this outbreak was caused by talking with the index case-patient at close range, which indicates droplet transmission,? wrote Ke Han, a researcher with the Chinese Center for Disease Control and Prevention in Beijing, and colleagues. ?Conversely, other kinds of contact, such as dining at the same table and receiving chewing gum from the index case-patient, played no role during this outbreak.?
The researchers, who included officials from provincial disease-control centers, studied the outbreak to identify the source of infection, mode of transmission and risk factors.
?Distinctive Hairstyle?
The index case had ?a highly distinctive hairstyle, which made her easy to remember,? the authors wrote.
Nine of the 16 tourists who spoke with the infected woman, or index case, at close range for 2 minutes or more caught the new H1N1 influenza virus, whereas none of the 14 tourists who didn?t talk to her became ill, according to the study.
Tour group members who talked to the woman for at least 10 minutes were almost five times as likely to become ill than those who spoke with her for 2 to 9 minutes, they said.
During this outbreak, the woman had a fever while traveling on three flights, and a person who subsequently became infected also flew while feverish, they said. A third patient caught a flight while suffering from a headache.
The fevers weren?t detected by thermal scanning at airports, according to the study. All three passengers didn?t truthfully inform health authorities of their symptoms in health questionnaires they were required to complete, the report said.
?These data suggest that thermal scanning and health questionnaires at the airports were not effective for detecting pandemic (H1N1) 2009 infections,? the authors said. :tiphat:http://www.bloomberg.com/apps/news?pid=20601080&sid=aUPeH8T6FYgg
