Infection patterns suggest a link between warm winters followed by more severe outbreaks
By Summit Voice
FRISCO — After study waves of flu sickness going back to about 1997 and matching them against climate records, researchers say that the warmer winters expected with global warming could lead to earlier and more severe flu seasons.
The researchers said data from the Centers for Disease Control, indicates a pattern for both A and B strains: Warm winters are usually followed by heavy flu seasons.
“It appears that fewer people contract influenza during warm winters, and this causes a major portion of the population to remain vulnerable into the next season, causing an early and strong emergence,” said Sherry Towers, research professor in the Mathematical, Computational and Modeling Sciences Center at Arizona State University. “And when a flu season begins exceptionally early, much of the population has not had a chance to get vaccinated, potentially making that flu season even worse.”
The current flu season, which is still in high gear in parts of the nation, began early and fiercely. It followed a relatively light 2011 season, which saw the lowest peak of flu since tracking efforts went into effect, and coincided with the fourth warmest winter on record. According to previous studies, flu transmission decreases in warm or humid conditions.
If global warming continues, warm winters will become more common, and the impact of flu will likely be more heavily felt, say the study’s authors.
The study could help public health officials prepare for flu oubreaks, said epidemiologist Gerardo Chowell-Puente, an associate professor in the School of Human Evolution and Social Change in the College of Liberal Arts and Sciences.
“The expedited manufacture and distribution of vaccines and aggressive vaccination programs could significantly diminish the severity of future influenza epidemics.”
The research was published online Jan. 28 in PLOS Currents: Influenza.