Alternate Names : Influenza
What can be done to prevent the infection?
An injection of flu vaccine every year
can provide protection for people who want to avoid the flu. The flu vaccine is
produced roughly 9 to 12 months ahead of the flu season. The formula used is
based on what experts believe will be the most common strains of flu virus in
the coming season. The vaccine has a 60% to
70% success rate in preventing the different types of influenza viruses each
The vaccine is recommended for people considered
to be at high risk. These include:
people over age 50
children and adults with
heart disease and lung disease, including asthma
people who live in nursing homes or other institutional settings
people who have a chronic disease such as diabetes, asthma, anemia, or
people who can transmit the flu to others at high risk. This group
includes healthcare workers and employees at facilities caring for people
at high risk.
women who will be in the second or
third trimester of pregnancy during
the flu season
people whose immune system is weakened because of chemotherapy
people with HIV or AIDS
A recent study showed that the flu vaccine may also be effective in preventing
second heart attacks in people who have already had a heart attack. In the study, people who received the flu
vaccine had a 67% lower incidence of a second heart attack than the people who
were not vaccinated that year.
Elderly individuals who are vaccinated against the flu have a significantly
lower incidence of hospitalization for respiratory disease, congestive heart failure, and death from any
About 25% of adults who receive the flu vaccine report mild soreness at
the site of the injection. Young children may develop fever after a flu
vaccine. There is also a slight risk of an allergic reaction to the vaccine. A nasal vaccine for the flu
is being tested and may soon be available.
What are the long-term effects of the infection?
While most people recover from the flu without problems, others can develop
complications such as:
pneumonia, an acute lung infection
that can be caused by a virus or bacteria
acute bronchitis, an infection of
secondary bacterial infections, which are infections caused by other germs
besides those causing the flu infection
congestive heart failure
Influenza and its complications can cause serious disease or even death.
What are the risks to others?
The influenza virus is highly contagious. It is transmitted through respiratory
secretions. Sneezing and coughing can
spread these droplets. The virus can also be passed on when an individual with
the flu touches his or her nose and then handles an object that another person
later touches. The second person can then pick up the virus from the object and
transfer it into his or her own respiratory tract by touching the