Many people think of the flu as just a terrible cold. But the two are different in terms of cause, symptoms and treatment. There are some 200 viruses to cause colds and their symptoms are local: a runny nose, coughs, phlegm or sore throat. But flu is caused by influenza viruses. They affect the whole body, causing the familiar fatigue and aches. Colds don't require any special treatment and go away naturally in two to five days, but for flu there are treatment and vaccines.

Immunization

Jabs do not guarantee 100 percent protection from flu. They prevent flu in 70-90 percent of healthy young adults, but the figure goes down to 30-40 percent in those over 65. Immunization, however, weakens symptoms when you do get flu, reducing mortality by complications by 80 percent in those over 65.

Everyone needs to get vaccinated

Flu is not much of a problem for those between 20 and 50. They may have to spend several days in bed, but they rarely come down with fatal complications. In fact, the World Health Organization recommends immunization for only one-third of the total world population. Korea depends on imports for its flu vaccines, and healthy young adults don't need to get immunized, doctors say.

Babies

Immunization is all too important for children between six month and two years old. Newborns under six months maintain immunity they got from their mother and don't need to get immunized, but after that they become vulnerable to flu as their natural immunity disappears and their immune system remains undeveloped. This is why infants between six and 24 months are the first to get vaccinated. Some 80.5 percent of children between thee and five now get their jabs, but the rate plummets to 46.2 percent for children between six months and 24 months old in Korea.

Jabs during pregnancy

Women in an early phase of pregnancy tend to avoid immunization because they worry about the effects on the unborn baby. But the U.S. Centers for Disease Control and Prevention in a report published in July said it immunized some 2,000 pregnant women and found out that the injections did not harm their unborn babies.” But the risk is greater when pregnant women don't get immunized as frequent coughs and high fevers caused by flu prevent their fetus from getting enough oxygen, raising the risk of complications and miscarriage.

Timing

Many believe that flu spreads only in winter, but there are many flu patients in the spring too. The flu virus is the most active in temperatures between 4-10 degrees Celsius and when it is dry. If high-risk groups including the elderly haven't been immunized in the prime time of October and November, they need to do so by February or March the next year.

When to Avoid Vaccination

Those with chronic diseases such as diabetes, chronic lung disease and heart trouble should be the first to be immunized. Diabetics also need to get immunized because their high level of blood glucose reduces the ability of leucocytes to stop germs and viruses from invading their body

(englishnews@chosun.com )