Saturday
May022009
Pandemic Or What?
Coffee Brown MD, University of New Mexico, Talk Radio News
There are three main differences between a normal flu and a pandemic flu, as described by the Department of Homeland Security: incidence, virulence, and demographics.
Incidence refers to how many of us will get it. In a normal year, about 15 percent of 300 million Americans, or about 45 million people will get infected. In a pandemic, rates rise to 25-50 percent, or 75-150 million cases.
Virulence refers to how many of us will die of the infection. In a normal year, that’s about 0.07 percent, or about 35 thousand out those 45 million. In 1918, mortality was about 2.5 percent, which would be about 7.5 million deaths, given today’s population.
Demographics refers to which of us are at most risk. In a normal year, nearly all deaths occur in people over 65 years old. In 1918 and 1957, mortality was highest among school-aged children and young adults.
This summary, with some calculations, comes from information provided by DHS and presented at GlobalSecurity.Org
Let’s compare the 2009 A-H1N1 Flu. “Atypical flu” may be a handier name. “Swine flu” is passe’.
Incidence: As of 05/02/09: There have been 615 confirmed cases in 15 countries. Attack rates so far are too low and data too incomplete to meaningfully calculate.
Virulence: Mortality in Mexico, the country hardest hit so far, is 16 out of 397 cases: about 4 percent, which works out to four thousand per hundred thousand (a common way of expressing this type of number).
The one U.S. death might properly have been considered a Mexican death, since that child contracted the disease there. If calculated as U.S. data: one death out of 141 cases: about point seven percent. If that fatality is not charged to the U.S. account, the mortality rate outside of Mexico is zero percent as of this writing.
Demographics: Reports say that the Mexican victims were young, but I have not been able to locate details to confirm that. The World Health Organization says that more study would be needed to confirm that younger people are more at risk.
Other: The other elements of this flu that merit precautions are that it is genetically unique, meaning we may have no immunity, and that it is slightly out of season, meaning that it exhibits at least some unpredictable behavior.
We are still at phase 5, so clusters of cases in multiple countries, which would define phase 6, have not yet been confirmed.
Per the WHO, there no travel advisories at this time.
Do masks help? Yes, no, and maybe. Yes: as tiny as viruses are, they could slip right through any screen that we could breathe through, but the virus is carried in droplets of exhaled moisture, and those droplets do stick to the mask. No: But the masks dry, and it’s not clear whether the virus survives and detaches into the inhaled air. Maybe: the real test would be whether people with masks get fewer infections (though such people probably also take more precautions in general), and the Centers for Disease Control and Prevention says that data is not yet available.
There are three main differences between a normal flu and a pandemic flu, as described by the Department of Homeland Security: incidence, virulence, and demographics.
Incidence refers to how many of us will get it. In a normal year, about 15 percent of 300 million Americans, or about 45 million people will get infected. In a pandemic, rates rise to 25-50 percent, or 75-150 million cases.
Virulence refers to how many of us will die of the infection. In a normal year, that’s about 0.07 percent, or about 35 thousand out those 45 million. In 1918, mortality was about 2.5 percent, which would be about 7.5 million deaths, given today’s population.
Demographics refers to which of us are at most risk. In a normal year, nearly all deaths occur in people over 65 years old. In 1918 and 1957, mortality was highest among school-aged children and young adults.
This summary, with some calculations, comes from information provided by DHS and presented at GlobalSecurity.Org
Let’s compare the 2009 A-H1N1 Flu. “Atypical flu” may be a handier name. “Swine flu” is passe’.
Incidence: As of 05/02/09: There have been 615 confirmed cases in 15 countries. Attack rates so far are too low and data too incomplete to meaningfully calculate.
Virulence: Mortality in Mexico, the country hardest hit so far, is 16 out of 397 cases: about 4 percent, which works out to four thousand per hundred thousand (a common way of expressing this type of number).
The one U.S. death might properly have been considered a Mexican death, since that child contracted the disease there. If calculated as U.S. data: one death out of 141 cases: about point seven percent. If that fatality is not charged to the U.S. account, the mortality rate outside of Mexico is zero percent as of this writing.
Demographics: Reports say that the Mexican victims were young, but I have not been able to locate details to confirm that. The World Health Organization says that more study would be needed to confirm that younger people are more at risk.
Other: The other elements of this flu that merit precautions are that it is genetically unique, meaning we may have no immunity, and that it is slightly out of season, meaning that it exhibits at least some unpredictable behavior.
We are still at phase 5, so clusters of cases in multiple countries, which would define phase 6, have not yet been confirmed.
Per the WHO, there no travel advisories at this time.
Do masks help? Yes, no, and maybe. Yes: as tiny as viruses are, they could slip right through any screen that we could breathe through, but the virus is carried in droplets of exhaled moisture, and those droplets do stick to the mask. No: But the masks dry, and it’s not clear whether the virus survives and detaches into the inhaled air. Maybe: the real test would be whether people with masks get fewer infections (though such people probably also take more precautions in general), and the Centers for Disease Control and Prevention says that data is not yet available.
tagged 
A-H1N1 flu, Atypical Flu, Centers for Disease Control and Preventio, Coffee Brown MD, Department of Homeland Security, GlobalSecurity.Org, Incidence, University of New Mexico, Virulence, WHO, demographics, dhs, pandemic, swine flu, talk radio news, world health organization in News/Commentary
A-H1N1 flu, Atypical Flu, Centers for Disease Control and Preventio, Coffee Brown MD, Department of Homeland Security, GlobalSecurity.Org, Incidence, University of New Mexico, Virulence, WHO, demographics, dhs, pandemic, swine flu, talk radio news, world health organization in News/Commentary
Got Dengue Fever? Blame Climate Change
As if melting glaciers, higher sea levels and unpredictable weather weren't enough, because of global warming, the human race faces the potential spread of infectious diseases. A panel of climate experts on Monday discussed the possibility of this occurring in North America.
“Climate change will likely alter the current distribution of vectors and/or pathogens,” said Mary Hayden, a scientist with Centers for Disease Control. “Two major climate factors that promote the reproduction of infectious mosquitos are precipitation and temperature.”
Hayden predicts that by 2050, Aedes aegypti, the yellow fever mosquito, will likely migrate from areas in Mexico to U.S. cities along the Eastern seaboard. Additionally, outbreaks of Dengue fever have already been reported in Key West, Florida.
“Unfortunately, we’re seeing that Dengue Fever is increasing in number and severity. In Mexico alone, since 2005, there has been a 600 percent increase in cases, with no known vaccine,” said Hayden.
The panel used years of data that shows correlations between increased rainfall accumulations in Africa and the reproduction of water-thriving mosquitoes, with the spread of diseases including Dengue Fever, Malaria, Cholera and Hantavirus.
According to the World Health Organization's website: “Change in world climate would influence the functioning of many ecosystems and their member species. Likewise, there would be impacts on human health. Some of these health impacts would be beneficial. For example, milder winters would reduce the seasonal winter-time peak in deaths that occurs in temperate countries, while in currently hot regions a further increase in temperatures might reduce the viability of disease-transmitting mosquito populations. Overall, however, scientists consider that most of the health impacts of climate change would be adverse.”
The panel on Monday urged Congress to develop a comprehensive disease control and monitoring system that will help combat the onset of diseases that have increased in recent years.
“I believe Congress should be focused on our ability to monitor and track diseases generally, but particularly with diseases related to climate change,” said panelist Lynn Goldman, a professor at the Johns Hopkins University Bloomberg School of Public Health. “Right now we are doing a good job, but certainly monitoring can be very much improved.”