Medical sleuths have been trailing the elusive cold and flu viruses for more
than a century. Now they finally might be onto something. A universal flu
vaccine could be on the horizon -- and even more effective treatments for the
common cold. Wayne Marasco, MD, PhD, is one of the most ardent sleuths. His
perp -- the flu virus -- has caused the deaths of more than 36,000 Americans,
and that’s just in one year.
Marasco is an associate professor of medicine at the Dana-Farber Cancer
Institute and Harvard Medical School. His work means that a universal flu
vaccine could be within reach -- one that would protect against all flu strains
over a lifetime, just like existing vaccinations for diseases like measles and
smallpox. Up to now, a universal flu vaccine has been elusive, because the
virus's constant ability to change has made it a hard target to combat. "The
virus undergoes a process we call antigenic drift, which means that it
continuously evolves so that it escapes the immune system," he explains. "We've
been kind of chasing our tails and immunizing every season to keep up with
The hepatitis A vaccine can prevent hepatitis A -- a serious, sometimes fatal, liver disease, which can require hospitalization. The hepatitis A virus, present in the stool of infected people, spreads through:
Close personal contact, such as household or sexual contact, with an infected person
Contaminated water or ice
Contaminated raw shellfish, fruits, vegetables, or other uncooked foods
If you get hepatitis A as an adult, you are more likely to have signs and symptoms than young...
Even though only two different types of flu virus -- A and B -- are
responsible for most human flu cases, each type has several subtypes, and the
virus can change from season to season. That's why researchers can never seem
to keep up.
The 1918 Flu Pandemic
Compounding the problem is that people are always on the move. Hundreds of
years ago, Europeans first carried the flu to North America on ships, infecting
Native Americans who had previously been flu-free. Today, air travel can speed
flu viruses (including the H1N1, or swine, flu) around the world even faster.
Last year swine flu was reported for the very first time among the Matsigenka
tribe deep in the Amazon jungle, proving that no place is too remote to escape
a flu bug.
Even before the age of commercial air travel, the flu virus was able to get
around. In 1918, after the influenza A virus jumped from birds to humans,
soldiers in World War I spread the disease as they moved around the European
front. By the time the worldwide pandemic had ended a year later, a quarter of
Americans had become sick and 50 million people worldwide had died from the
illness, which was named the Spanish flu.