ASU scientist: Swine flu study requires revised public health strategies


July 1, 2009

Findings in New England Journal of Medicine point to younger populations

There is no way to know how the newest strain of the H1N1 influenza virus will behave in the future. But scientists, notably those working at the intersections of epidemiology, mathematics, modeling and statistics, are monitoring it closely to identify anomalies on its pattern of spread while evaluating ways of mitigating its impact. Download Full Image

"Public health officials have the ability to track confirmed cases and hospitalizations in real-time with modern data collection approaches and the aid of modeling as well as the ability to quickly identify new strains and track their evolution," says mathematical epidemiologist Gerardo Chowell-Puente, an assistant professor at Arizona State University's School of Human Evolution and Social Change in the College of Liberal Arts and Sciences.

Chowell-Puente is co-author of a new study of the A(H1N1) influenza pandemic strain circulating around the world. The study's findings reveal an age shift in the proportion of cases toward a younger population when compared with historical patterns of seasonal influenza in Mexico. The findings are published June 29 online in the New England Journal of Medicine. Other authors of "Reported severe respiratory disease and deaths concurrent with atypical A(H1N1) influenza circulation of swine origin in Mexico, 2009" include Stefano Bertozzi and Arantxa Colchero, Mexico's National Institute of Public Health; Hugo Lopez-Gatell, Celia Alpuche and Mauricio Hernandez, Mexico Ministry of Health; and Mark A. Miller, National Institutes of Health Fogarty International Center,

"The data show that the vast majority of cases of severe pneumonia and deaths occurred among those ages between 5 and 59, which is atypical when compared with the age pattern supported by seasonal flu," says Chowell-Puente. "If resources or vaccine supplies are limited, focusing prevention efforts on these age classes must be considered."

Specifically, according to the findings, 87 percent of the deaths and 71 percent of the cases of severe pneumonia occurred in persons aged 5-59, compared to an average 17 percent and 32 percent, respectively, for influenza seasons from 2006 through 2008. "These findings suggest relative protection for those persons exposed to H1N1 influenza viruses during childhood prior to the 1957 pandemic," Chowell-Puente says.

Chowell-Puente and other mathematicians and biostaticians attending a swine flu workshop at Arizona State University June 25-28, note that vaccines and anti-viral medications are in limited supply.

"Because achieving high vaccination rates before the fall is not feasible with current technologies, effective distribution of a limited vaccine and antiviral stockpiles will be crucial to mitigate a potential second pandemic wave. The seasonal influenza vaccination strategy focuses on the very young and the very old - the most vulnerable populations. This is not necessarily the case for pandemics as we showed in our study."

According to Chowell-Puente, the key to containing pandemic flu is closely tied in to the ability to quickly produce a good stockpile of vaccines and following a reactive distribution plan that targets the appropriate age cohorts of the population. The first wave of the current strain has not been particularly deadly, but subsequent waves may be more virulent, though it is too early to tell, he notes.

"For the 1918 ("Spanish flu") influenza pandemic, this was the pattern - first a mild wave, and then a severe one with higher case fatality rates," notes Chowell-Puente.

The features of the A(H1N1) epidemic, according to the findings, are "somewhat similar to past influenza pandemics in that circulation of a new influenza virus is associated with an unseasonal wave of disease affecting a younger population."

It is the hope of Chowell-Puente that making this data available will help politicians make science-based decisions on how to optimize the use of limited resources to manage this and future epidemics.

In addition to this latest research, Chowell-Puente also was a co-author on a recent study of the flu in Japan. "Here we looked at the public health strategies they used that essentially stopped the spread of the disease in its tracks," he says.

The researchers found that in Japan, more than 90 percent of the cases were in school-aged children and teens. Quick action was taken to contain the disease through school closures and other social distancing measures, such as avoiding use of public transportation and the use of face masks. In addition, Japan employed active surveillance at airports, using recently developed sensors to detect passengers with fevers for additional screening. The disease was contained within two-to-three weeks, with only about 500 cases and no fatalities. Findings from this study appeared in the June 4 issue of Eurosurveillance in an article titled "Transmission potential of the new influenza A(H1N1) virus and its age-specificity in Japan."

Other authors on the Japanese study include: Hiroshi Nishiura, University of Utrecht, the Netherlands; Carlos Castillo-Chavez, Arizona State University; and Muntaser Safan, Mansoura University, Egypt.

Reducing the spread of the disease is key to preventing deaths, according to Chowell-Puente. "As transmissibility grows, timely implementation of control measures is key to reduce epidemic impact on the population."

Carol Hughes, carol.hughes">mailto:carol.hughes@asu.edu">carol.hughes@asu.edu
480-965-6375
College of Liberal Arts and Sciences

Jodi Guyot, jodi.guyot">mailto:jodi.guyot@asu.edu">jodi.guyot@asu.edu
480-727-8739
School of Human Evolution and Social Change

Weber named a Playboy All-American for the second straight year


July 1, 2009

Arizona State University junior place kicker Thomas">http://thesundevils.cstv.com/sports/m-footbl/mtt/weber_thomas00.html">Th... Weber (Downey, Calif.), has been named to the 2009 Playboy Magazine College Football All-American team, the magazine announced today. The members of the team will be announced in September when the issues hits the newsstands.

This is the second straight year that Weber has earned membership on the prestigious Playboy Magazine All-American team, having made it in 2008 as well following a fantastic freshman campaign. In the history of Sun Devil football, Weber becomes only the second player to be named to the Playboy All-America team twice. Cornerback Mike Richardson, who was a second-round draft pick (33rd selection overall) of the Chicago Bears in 1983, made the team in 1981 and 1982. Download Full Image

Weber becomes the 14th Sun Devil to be named to the Playboy All-America team. It is the 16th time an ASU player has been named to the squad (Weber and Richardson twice). Former Sun Devil head coach Bruce">http://thesundevils.cstv.com/sports/m-footbl/mtt/snyder_bruce00.html">Bruce Snyder was named to the team in 1997 as the National Coach-of-the-Year.

In 2008, Weber connected on 19 of 25 field goals, including a long of 49 yards. Three of his field goal tries were blocked. He his 29 of 30 extra points and scored 86 points to lead ASU. He also handled the punting duties, punting 59 times for a 41.4-yard average. He had a long punt of 61 yards.

In two years as a Sun Devil, Weber has hit 43 of 50 field goals, including a career-long 53-yarder. He has scored 204 points and sports a 40.5 yards per punt average on 106 punts. Weber is 33 of 36 on field goals inside 40 yards in his career.

Weber won the 2007 Lou Groza Award, which is presented annually to the nation's top place kicker, and was named to the 2008 Associated Press First-Team All-American squad.