DOES EXERCISE BUILD IMMUNITY?
What can we do to stay healthy this flu season besides hand and cough hygiene, avoid large crowds and eat well? What about exercise as a way to beat the flu! Two experiments addressed this issue and were written about recently in the NY Times.
The first was from the publication Brain, Behavior, and Immunity, where researchers divided mice into two groups. Over achievers – take notice! (I am also speaking about myself) One rested comfortably in their cages. The other ran on little treadmills until they were exhausted. This continued for three days. The mice were then exposed to an influenza virus.
The second experiment (published in the same journal) had scientists from the University of Illinois and other schools first infect laboratory mice with flu. One group then rested; a second group ran for a leisurely 20 or 30 minutes, an easy jog for a mouse; the third group ran for a taxing two and a half hours. Each group repeated this routine for three days, until they began to show flu symptoms. The flu bug used in this experiment is devastating to rodents, and more than half of the sedentary mice died. But only 12 percent of the gently jogging mice passed away.
Is this good news or bad? This is a particularly relevant question as two important human events converge: the peaking of the fall marathon and other sports seasons and the simultaneous onset of the winter cold and flu term. Scientists are diligently working to answer that question, perhaps because they are as interested as the rest of us in avoiding or lessening the severity of colds and the flu.
In this model, the risk both of catching a cold or the flu and of having a particularly severe form of the infection “drop if you exercise moderately,” says Mary P. Miles, PhD, an associate professor of exercise sciences at Montana State University and the author of an editorial about exercise and immunity published in the most recent edition of the journal Exercise and Sport Sciences Review. But the risk both of catching an illness and of becoming especially sick when you do “jump right back up” if you exercise intensely or for a prolonged period of time, surpassing the risks among the sedentary. (Although definitions of intense exercise vary among researchers, most define it as a workout or race of an hour or more during which your heart rate and respiration soar and you feel as if you are working hard.)
Why exercise should affect either your susceptibility to catching an illness or how badly a particular bug affects you is still unclear. It appears that intense workouts and racing suppress the body’s immune response for a period of time immediately after you’ve finished exercising and that “the longer the duration and the more intense” the exercise, “the longer the temporary period of immunosuppression lasts — anything from a few hours to a few days has been suggested,” says Nicolette Bishop, an associate professor of sport and exercise sciences at Loughborough University and the author of a review article about exercise and immunity published in January.
Exercise stress increases susceptibility to influenza infection http://www.ncbi.nlm.nih.gov/pubmed/18616997
Acute and chronic effects of exercise on markers of mucosal immunity. http://www.ncbi.nlm.nih.gov/pubmed/19273362
TRUCK CARRYING FLU VACCINE SUPPLY IS STOLEN
The H1N1 vaccine which, is very difficult to find, has become a coveted commodity all over the country. It appears that someone in Milwaukee decided one way to get it was to steal a refrigerated truck that was hauling 930 doses.
The doses were being returned to Milwaukee’s main storage facility on Thursday evening after a public vaccination clinic when one or more people took off in the truck, which had been left idling and unattended only for moments, the authorities said.
The police found the truck 40 minutes later, and said the crime appeared to have been inspired more by the easily available vehicle than by the H1N1 vaccine inside. In fact, the vaccine was all found, apparently untouched and perhaps even unnoticed. The doses will now be sent back to their manufacturers, although Milwaukee, like seemingly every other city, has plenty of people hoping to get one. “Given that it was out of our chain of custody, we cannot validate the integrity of that vaccine,” said Bevan K. Baker, the city health commissioner.
As prosecutors considered charges against a man suspected in the theft, there was other fallout: the department will no longer employ the transport company involved, Mr. Baker said, and trucks bearing H1N1 doses will now be escorted by a police squad car. “We’re prepared to give this precious cargo its appropriate resting place” — in arms and noses, he said