Passage How Mobile Telephony Turned into a Health Scare

A not using them continuously 
B turning them off when not in use 
C mounting a mast on the building where you live or work 
D keeping healthy and getting enough sleep 
Passage 2. Some Facts and Theories about Flu 
 
The flu, more properly known as influenza, takes its name from the fact that it is so easily transmitted from person 
to person (influenza is the Italian word for ’influence’). Usually, contamination occurs through direct contact with 
secretions from an infected person. Its spread is 
also possible from contaminated airborne particles, such as those that occur when someone coughs or sneezes. 
However, it should be made clear that the risk is not great from simply being in the same room as an infected person, 
since the flu virus, unlike other respiratory viruses, does not dissolve in the air. Within 4-6 hours of someone catching 
the flu, the virus multiplies in infected cells and the cells burst, spreading the virus to other cells nearby. 
The spread continues for up to 72 hours, the exact length of time depending on the body’s immune system response 
and the strength of the particular strain of flu. The range of human responses to the flu virus has been of interest to 
scientists for many years. This is because the effect can vary from no infection to a rapid and deadly spread of the 
virus to many people. One area of study that has received particular attention is the immune system response of the 
individual. Where a 
person’s immune system is healthy, the virus is attacked as it enters the body, usually in the respiratory tract. This 
lessens the severity of the illness. In contrast, people with compromised immune systems (typical in the young, where 
it is not fully developed, or in the old and the sick, where it is not working efficiently), often suffer the worst effects. 
One of the body’s responses to flu is the creation of antibodies which recognise and destroy that particular strain of 
flu virus. What fascinates most researchers in the field is that the human body seems capable of storing these 
antibodies over a whole lifetime in case of future attack from the same or similar strains of flu. It was while 
researching these antibodies that scientists turned their attention back to what was possibly the worst ever flu 
pandemic in the world. The actual number of deaths is disputed, but the outbreak in 1918 killed between 20 and 50 
million people. It is also estimated that one fifth of the population of the world may have been infected. 
Through tests done on some of the survivors of the 1918 outbreak, it was discovered that, 90 years later, they still 
possessed the antibodies to that strain of flu, and some of them were actually still producing the antibodies. Work is 
now focused on why these people survived in the first place, with one theory being that they had actually been 
exposed to an earlier, similar strain, therefore developing immunity to the 1918 strain. It is hoped that, in the near 
future, we might be able to isolate the antibodies and use them to vaccinate people against further outbreaks. 
Yet vaccination against the flu is an imprecise measure. At best, the vaccine protects us from the variations of flu that 
doctors expect that year. If their predictions are wrong in any particular year, being vaccinated will not prevent us 
from becoming infected. This is further complicated by the fact that there are two main types of flu, known as 
influenza A and influenza B. Influenza B causes less concern as its effects are usually less serious. Influenza A, 
however, has the power to change its genetic make-up. Although these genetic changes are rare, they create entirely 
new strains of flu against which we have no protection. It has been suggested that this is what had happened 
immediately prior to the 1918 outbreak, with research indicating that a genetic shift had taken place in China. 
In 2005, another genetic shift in an influenza A virus was recorded, giving rise to the H5N1 strain, otherwise known 
as avian flu, or bird flu. Typical of such new strains, we have no way of fighting it and many people who are infected 
with it die. Perhaps more worrying is that it is a strain only previously found in birds but which changed its genetic 
make-up in a way that allowed it to be transmitted to humans. Most of the fear surrounding this virus is that it will 
change again, developing the ability to pass from human to human. If that change does happen, scientists and doctors 
can reasonably expect a death rate comparable to that which occurred in 1918 and, given that we can now travel more 
quickly and more easily between countries, infecting many more people than was previously possible, it could be 
several times worse. 

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