This is SCIENCE IN THE NEWS in VOA Special
English. I'm Bob Doughty.
I'm Faith Lapidus. Summer is a busy time
for travel. Today, we discuss ideas
about how to stay healthy on a long trip.
people have wondered whether they are safe from germs when they travel in small,
enclosed areas. They worry about close
contact with others who may be sick.
current spread of a swine influenza virus has added to these concerns. Recently, the World Health Organization
raised its warning about the new H1N1 virus to its highest level. W.H.O. Director-General Margaret Chan declared
the sickness a pandemic – a disease that has spread to many nations. Given this information, many people want to
know how safe is it to travel?
answers people are getting may seem conflicting. For example, a W.H.O. statement urged nations not to close their borders or limit
trade and travel. Director-General Chan said
cases are generally mild for most people. Still, W.H.O. officials continue to report new cases across the world.
the past, the W.H.O. and experts with America's Centers for Disease Control and
Prevention noted guidance for disease spread on airplanes. The experts said you could get infected only
if you sit within two rows of someone who is sick. That would be a distance of up to three
meters from the sick person. And this
was true only if you sat there for more than eight hours.
But a travel-health expert says this
guidance may not be helpful for swine flu. Mark Gendreau works at the Lahey Clinic Medical Center in the American
state of Massachusetts. He suggests steps
that could help prevent getting swine flu on an airplane.
His advice includes keeping the airflow over your seat
on the "low" position. The doctor says
you should point the device so the flow of air is just in front of your
Infection can spread through
touching an infected surface and then touching your eyes, nose or mouth. Doctor Gendreau suggests cleaning your hands
with soap and water, or using hand-sanitizer wipes. These products should contain at least fifty
percent alcohol. In addition, he said
you may want to cover your face with a mask. Most importantly, avoid traveling when you are sick.
people do not get sick while taking long trips. But something else might interfere with your travel plans. You could be placed in medical isolation if
someone you traveled with on a plane is suspected of having swine flu.
The top official of an American city recently had this
experience. New Orleans Mayor Ray Nagin,
his wife and a security guard spent several days in a hospital-like center in
Shanghai, China. At the time, they were
on their way to Australia. Mayor Nagin
was preparing to speak there. But they
were detained because of someone who sat near them on their arriving flight. The person was suspected of having swine flu. The Nagins did not get sick.
from a high school in Maryland had a similar experience. On a recent visit to China, the students had
to spend several days in hotel rooms in the city of Kaili. They were barred from leaving their rooms
because someone on their flight was suspected of having the flu. Tests later proved that the suspicion was
The students lost several days of sight-seeing. But one girl said she was still glad she made
other people share her feeling. One man
from Maryland says he has planned a trip to Ireland for many years. He wants to visit the burial places of his
grandparents. He says it will take more
than a pandemic to keep him from making his trip.
Technology on most airplanes might make you feel safer
about air travel. The United States
Federal Aviation Administration says most large passenger planes now use HEPA
filters. The devices are designed to
remove dangerous particles from the air.
letters H-E-P-A represent the words High Efficiency Particulate Air. HEPA filters capture almost all particles in
the air that are zero point three microns in size or larger.
Atomic Energy Commission developed HEPA filters many years ago. The goal was to protect workers who were
developing the atomic bomb. The first
HEPA filters removed radioactive particles from the air. Today, the filters clean the air in planes.
Centers for Disease Control says HEPA filters are effective in clearing the air
of many particles that cause disease. Makers of the devices say they kill bacteria and viruses because they
help to remove the wetness that germs need to survive. But HEPA filters cannot remove
disease-causing particles smaller than zero point three microns. These will continue to move around in the air
and can infect people.
On a passenger cruise
ship, fresh air is available on decks and in other places above sea level. A spokesperson for the Cruise Lines
International Association says other air quality depends on the requirements of
the nation where a ship was built.
say people should know about other health concerns that can strike when
traveling by air. One of these is
hypoxia. It results from a lack of
oxygen to the brain. Experts say the
body begins losing oxygen minutes after an airplane leaves the ground.
air pressure in a plane during flight is lower than at sea level. This makes it more difficult for the body to
effectively use the same amount of oxygen as it would on the ground. Fewer oxygen molecules cross the tissues in
the lungs and reach the bloodstream.
The result is a five to twenty percent drop in the
amount of oxygen in the blood. This
reduces the amount of oxygen that reaches the organs of the body.
One effect of this lack of oxygen to the
brain is a headache. When this happens,
the heart attempts to fix the situation by beating harder and faster. This can make the traveler feel tired.
signs of hypoxia are not dangerous in a healthy person. But a drop in oxygen levels can cause a
health emergency in people with heart or lung problems. They might lose consciousness or even suffer
a heart attack.
say use of cigarettes and alcoholic liquids also reduces the body's ability to
use oxygen. So they suggest that people
not drink alcohol or smoke cigarettes either before or during a flight. They also say persons with heart or lung
problems should seek advice from their doctor before flying.
Another problem for travelers can be a condition called
deep vein thrombosis. A thrombosis is a
blood clot -- a condition in which some blood thickens and blocks the flow to
the heart. Blood clots can kill if they
move to the heart and lungs and stop needed oxygen from reaching those important
organs. This is known as a pulmonary
The World Health Organization says
passengers who sit still for four or more hours face a greater risk of
developing blood clots. But it says only
one in six thousand people develop deep vein thrombosis.
week, Harvard University researchers reported that people who travel are three
times more likely than others to develop deep vein thrombosis. The researchers examined information from
fourteen earlier studies. They found the
longer the trip, the greater the threat of deep vein thrombosis. They even found a measurable increase in the
condition for every two hours sitting in a car.
say the chance of a clot also increases if a person does not drink enough
water. They say passengers who sit for
hours need to drink plenty of water -- not liquids that contain alcohol or
caffeine. Passengers should also
increase blood flow to the legs. The
doctors suggest covering your legs with support stockings and walking every
hour or so during the trip. Or, at least
move your legs and feet.
Doctors say anyone with pain, swelling or red skin on a
leg during or after a long trip may have a blood clot. Anyone with such signs should see a doctor as
soon as possible. The condition many
times can be treated with drugs that thin the blood and stop the clot from
moving through the body.
This SCIENCE IN THE NEWS
was written by Nancy Steinbach and Jerilyn Watson. Our producer was Brianna Blake. I'm Bob Doughty.
And I'm Faith Lapidus. Read and listen to our programs at
voaspecialenglish.com. Join us again
next week for more news about science in Special English on the Voice of