Lethal Flu Gene (10.14.04) - New research on the deadliest flu virus ever shows how acquiring a single gene can transform a mild strain of flu into a killer.
Flu Shot Shortage Risk (10.06.04) - This year's sudden flu shot shortage may have some health consequences beyond just this year. Researchers have found that alternately getting and skipping flu shots may actually increase your chance of getting sick.
Scientists have found that a simple spray may be an effective way to fight the flu. As this ScienCentral News video reports, the idea of the aerosol is to try to keep people from giving their germs to others.
Just Breathe
Mom always told us to cover our mouths when we coughed or sneezed. Scientists have now found that, while mother was right, her advice may not be going far enough. Researchers at Harvard University have found that, for some people, just breathing appears to be an effective way to spread disease.
When a person exhales, tiny droplets from the fluids lining the lungs spray into the air— just as when a gust of wind hits the ocean and flings some water into the air. These droplets can carry disease-causing agents or pathogens, including the flu virus, SARS, and tuberculosis, as well as bacteria like bronchitis, E. coli, and even anthrax. "They can travel really for miles and miles without depositing," says David Edwards of Harvard University's Division of Engineering and Applied Sciences. "Obviously when one speaks or talks or coughs, larger particles come out too, and the larger particles tend to be more prone to settling by gravity and, therefore, are more of a concern on intimate contact."
A small study conducted at Harvard found that about half of the healthy people studied exhale far more of these droplets than the other half, and that an inhaled spray could control the number of pathogens they exhale, potentially decreasing the transmission of infectious diseases. "There is the opportunity to have a potentially over-the-counter treatment for either hospital environments or confined environments like prisons or even, frankly, homes," says Edwards.
image: ABC News
In the two-part study, researchers tested a saline spray— salty water similar to the fluids in the body— to determine if coating the inner lining of the lungs with a salty mist would reduce the number of pathogens people exhale when they breathe normally through their mouths. First, they found that six of 11 healthy men ("high producers") exhaled many more droplets into the air than the study's five other participants ("low producers")— hundreds and sometimes thousands of particles per liter for the high producers versus ten to 20 for the low producers.
In the second part of the study, Edwards' team had each group breathe in a dose of the spray through a device called a nebulizer and monitored the number of pathogens released over time. The spray reduced the amount of droplets exhaled by the high producers by 72 percent over a six-hour period. This reduction accounted for 98 percent of all the droplets released by the entire group. "Our idea was to deliver the saline…to affect the physical properties of the surface and to diminish the number of particles that are being created," Edwards explains. "More particularly, to make those particles bigger so that they would actually fall out in the lungs and not be expired."
The spray is designed to increase the surface tension of the lungs, tightly locking particles in place. It has a secondary effect of decreasing the viscosity, or fluid stickiness, inside the lungs. The result is that the tiny viruses and bacteria we all have in our lungs clump together and are less likely to take flight when we breathe. The particles that stay in the lungs are filtered into the body and destroyed by white blood cells.
Edwards adds that there may be some benefit from the spray for a person who already has the flu; the same breathing that causes pathogens to travel out of the lungs can also lodge them deep within our lungs. For example, influenza often begins in the upper respiratory tract. Breathing pushes the virus deep into the lungs. By increasing the surface tension and viscosity of the lungs' fluid lining, there's an overall decrease in pathogen travel throughout the respiratory tract. "If we're delivering a fluid which is diminishing the amount of particles coming out of the lungs, very likely we're diminishing the particles that are going deep," Edwards says. "The bottom line is that the treatment may also have a protective effect on the individual receiving the saline."
delicious
digg
magnolia
reddit
newsvine
netscape
netvibes
