sharon sanders
Editor-in-Chief & President
May 5 (Bloomberg) -- The virulence of the swine flu that has sickened at least 1,124 people in 21 countries may reveal itself when the Southern Hemisphere faces its influenza season that begins this month, global health authorities say.
The World Health Organization said it?s bracing for the possibility the disease will worsen as the weather in those countries cools, despite reports symptoms are no more severe than seasonal flu. The outbreak is easing in Mexico, where it struck hardest, Health Minister Jose Cordova said yesterday.
The WHO will monitor the Southern Hemisphere during the flu season through to September, according to Keiji Fukuda, the agency?s assistant director-general for health, security and environment. Data from the region may help scientists develop a vaccine against the virus, formally known as influenza A (H1N1), amid concern it may mutate and become the dominant strain.
?Information from the Southern Hemisphere is going to be pivotal to strategies to be used for the coming Northern Hemisphere winter, and decisions as to vaccine production,? said Lance Jennings, an associate professor at the University of Otago in New Zealand. ?We are getting near the period where traditionally influenza viruses are spread efficiently.?
In Mexico, the onset of warmer temperatures may be helping quell the flu, said Miguel Angel Lezana, director of the National Center for Epidemiology Control. The swine flu was spreading at about the same rate as seasonal flu, with each new patient infecting, on average, about 1.5 people, said Lezana. The number is an early estimate and may change, he said.
?Benign Form?
?What we see now is a rather benign form of the virus, but it?s a young virus and we don?t know how it might develop,? Peter Cordingley, a spokesman with the WHO in Manila, said today by phone. ?The chances of mutation are very real.?
The three main seasonal flu strains -- H3N2, another form of H1N1, and type-B -- cause 250,000 to 500,000 deaths a year globally, according to the WHO. The new flu?s symptoms are similar: aches, coughing, and fever. (also diarrhea in 50% - Fla1)
?All assessments of this virus and what is likely to happen are really going to rely on improving our surveillance globally so we can keep track of it,? said Jennings, who advises New Zealand on pandemic-preparedness plans.
In the U.K., six students from Alleyn?s School in southeast London are receiving treatment for swine flu, and the establishment has been closed, the school said on its Web site.
Swine flu is suspected in people in 44 of the 50 U.S. states, and the infected may number in the thousands, U.S. health officials said. Even if symptoms are mild, the ease with which the new virus spreads among a world population with no natural immunity makes it a threat, according to the U.S. Centers for Disease Control and Prevention in Atlanta.
?Other Viruses?
?Here in the United States, we?re at the very end of our flu season,? Richard Besser, acting chief of the CDC, said in a conference call yesterday. ?There aren?t a lot of other flu viruses around that it?s competing with. What happens when it goes into countries where there are other viruses circulating??
While small outbreaks may occur in schools or other closed settings, community-wide spread of flu has never been seen in the Northern Hemisphere from May through August, said Ira Longini, a University of Washington statistician who advises the U.S. government on influenza. The burst of cases in Mexico in April may be winding down with the end of flu season, he said.
?Mild? Cases
?We?re cautiously optimistic this particular strain will not be more severe than a normal seasonal flu outbreak,? Janet Napolitano, the U.S. secretary for homeland security, told reporters in Washington yesterday. The ?large majority? of the cases are ?mild,? have not required hospitalization, and many of the patients have recovered, she said.
The WHO, the Geneva-based agency of the United Nations, yesterday added Colombia, El Salvador and Portugal to the list of countries with confirmed cases. The other nations are Austria, Canada, Costa Rica, Denmark, France, Germany, China (Hong Kong), Ireland, Israel, Italy, Mexico, the Netherlands, New Zealand, South Korea, Spain, Switzerland, the U.K., and the U.S.
In the U.S., H1N1 has been confirmed by laboratory tests in 286 patients in each of nine regions tracked by the U.S. census, the CDC reported. There are 101 cases in Canada, according to the WHO. Mexico said late yesterday it had confirmed 26 deaths among its 802 cases.
School Closures
Data so far suggest the virus is striking younger patients than is typical for influenza, and younger patients than usual are entering hospitals, said Anne Schuchat, a scientist at the CDC. ?Very few? patients with swine flu are older than 50, and the median age is 17. It?s possible that older people have greater immunity, she said in a conference call on May 3.
The U.S. strategy to close schools with suspected cases doesn?t effectively halt the virus?s spread once it becomes established in an area, Besser, of the CDC, said. The agency is evaluating whether to change its advice to schools, he said.
About 533 schools in 24 states in the U.S. were closed yesterday for the flu, shutting out about 330,000 students, according to the U.S. Department of Education.
While there is no vaccine against swine flu, shots are the most efficient and cheapest way to fight a pandemic, said Longini, the biostatistician who advises the government on flu. Closing schools, for example costs about 20 times more, mainly because of lost work hours and services, he said.
?No Idea?
The U.S. is hastening production of its annual flu shots based on strains identified before the H1N1 outbreak, said Kathleen Sebelius, who was confirmed as the U.S. Health and Human Services secretary last week. That will make capacity available if vaccines are needed for swine flu, she said.
Batches of seed virus are being developed for potential vaccine production, according to the WHO. Sanofi-Aventis SA of Paris, Baxter International Inc. of Deerfield, Illinois, and GlaxoSmithKline Plc of London, are talking with world health authorities about producing shots, the agency said.
Authorities advised hand-washing, hygiene and staying home if sick as the most effective ways to control the outbreak. The WHO and CDC said closing borders or killing animals are costly steps that wouldn?t slow the spread of flu.
?People who tell you what flu is going to do have no idea what they?re talking about,? said Michael Osterholm, a flu expert at the University of Minnesota. ?We have no idea.?
To contact the reporters on this story: Tom Randall in New York at trandall6@bloomberg.net; John Lauerman in Mexico City at jlauerman@bloomberg.net
http://www.bloomberg.com/apps/news?pid=20601103&sid=a.b25lN14A.I&refer=us
The World Health Organization said it?s bracing for the possibility the disease will worsen as the weather in those countries cools, despite reports symptoms are no more severe than seasonal flu. The outbreak is easing in Mexico, where it struck hardest, Health Minister Jose Cordova said yesterday.
The WHO will monitor the Southern Hemisphere during the flu season through to September, according to Keiji Fukuda, the agency?s assistant director-general for health, security and environment. Data from the region may help scientists develop a vaccine against the virus, formally known as influenza A (H1N1), amid concern it may mutate and become the dominant strain.
?Information from the Southern Hemisphere is going to be pivotal to strategies to be used for the coming Northern Hemisphere winter, and decisions as to vaccine production,? said Lance Jennings, an associate professor at the University of Otago in New Zealand. ?We are getting near the period where traditionally influenza viruses are spread efficiently.?
In Mexico, the onset of warmer temperatures may be helping quell the flu, said Miguel Angel Lezana, director of the National Center for Epidemiology Control. The swine flu was spreading at about the same rate as seasonal flu, with each new patient infecting, on average, about 1.5 people, said Lezana. The number is an early estimate and may change, he said.
?Benign Form?
?What we see now is a rather benign form of the virus, but it?s a young virus and we don?t know how it might develop,? Peter Cordingley, a spokesman with the WHO in Manila, said today by phone. ?The chances of mutation are very real.?
The three main seasonal flu strains -- H3N2, another form of H1N1, and type-B -- cause 250,000 to 500,000 deaths a year globally, according to the WHO. The new flu?s symptoms are similar: aches, coughing, and fever. (also diarrhea in 50% - Fla1)
?All assessments of this virus and what is likely to happen are really going to rely on improving our surveillance globally so we can keep track of it,? said Jennings, who advises New Zealand on pandemic-preparedness plans.
In the U.K., six students from Alleyn?s School in southeast London are receiving treatment for swine flu, and the establishment has been closed, the school said on its Web site.
Swine flu is suspected in people in 44 of the 50 U.S. states, and the infected may number in the thousands, U.S. health officials said. Even if symptoms are mild, the ease with which the new virus spreads among a world population with no natural immunity makes it a threat, according to the U.S. Centers for Disease Control and Prevention in Atlanta.
?Other Viruses?
?Here in the United States, we?re at the very end of our flu season,? Richard Besser, acting chief of the CDC, said in a conference call yesterday. ?There aren?t a lot of other flu viruses around that it?s competing with. What happens when it goes into countries where there are other viruses circulating??
While small outbreaks may occur in schools or other closed settings, community-wide spread of flu has never been seen in the Northern Hemisphere from May through August, said Ira Longini, a University of Washington statistician who advises the U.S. government on influenza. The burst of cases in Mexico in April may be winding down with the end of flu season, he said.
?Mild? Cases
?We?re cautiously optimistic this particular strain will not be more severe than a normal seasonal flu outbreak,? Janet Napolitano, the U.S. secretary for homeland security, told reporters in Washington yesterday. The ?large majority? of the cases are ?mild,? have not required hospitalization, and many of the patients have recovered, she said.
The WHO, the Geneva-based agency of the United Nations, yesterday added Colombia, El Salvador and Portugal to the list of countries with confirmed cases. The other nations are Austria, Canada, Costa Rica, Denmark, France, Germany, China (Hong Kong), Ireland, Israel, Italy, Mexico, the Netherlands, New Zealand, South Korea, Spain, Switzerland, the U.K., and the U.S.
In the U.S., H1N1 has been confirmed by laboratory tests in 286 patients in each of nine regions tracked by the U.S. census, the CDC reported. There are 101 cases in Canada, according to the WHO. Mexico said late yesterday it had confirmed 26 deaths among its 802 cases.
School Closures
Data so far suggest the virus is striking younger patients than is typical for influenza, and younger patients than usual are entering hospitals, said Anne Schuchat, a scientist at the CDC. ?Very few? patients with swine flu are older than 50, and the median age is 17. It?s possible that older people have greater immunity, she said in a conference call on May 3.
The U.S. strategy to close schools with suspected cases doesn?t effectively halt the virus?s spread once it becomes established in an area, Besser, of the CDC, said. The agency is evaluating whether to change its advice to schools, he said.
About 533 schools in 24 states in the U.S. were closed yesterday for the flu, shutting out about 330,000 students, according to the U.S. Department of Education.
While there is no vaccine against swine flu, shots are the most efficient and cheapest way to fight a pandemic, said Longini, the biostatistician who advises the government on flu. Closing schools, for example costs about 20 times more, mainly because of lost work hours and services, he said.
?No Idea?
The U.S. is hastening production of its annual flu shots based on strains identified before the H1N1 outbreak, said Kathleen Sebelius, who was confirmed as the U.S. Health and Human Services secretary last week. That will make capacity available if vaccines are needed for swine flu, she said.
Batches of seed virus are being developed for potential vaccine production, according to the WHO. Sanofi-Aventis SA of Paris, Baxter International Inc. of Deerfield, Illinois, and GlaxoSmithKline Plc of London, are talking with world health authorities about producing shots, the agency said.
Authorities advised hand-washing, hygiene and staying home if sick as the most effective ways to control the outbreak. The WHO and CDC said closing borders or killing animals are costly steps that wouldn?t slow the spread of flu.
?People who tell you what flu is going to do have no idea what they?re talking about,? said Michael Osterholm, a flu expert at the University of Minnesota. ?We have no idea.?
To contact the reporters on this story: Tom Randall in New York at trandall6@bloomberg.net; John Lauerman in Mexico City at jlauerman@bloomberg.net
http://www.bloomberg.com/apps/news?pid=20601103&sid=a.b25lN14A.I&refer=us