Flu Season
Influenza is a highly infectious disease that affects humans, birds and other mammals as well. It is caused by the Influenza virus, that is highly pathogenic in nature. The influenza virus can be divided into 3 classes viz. A, B and C. each of these classes is further subdivided into many subtypes and each of these subtypes contain many strains of the virus. As such a large number of viruses cause the disease, it is difficult to control the same using vaccines and medication.
Many pandemics of this disease have occurred in the past. Apart from them, many epidemics of the disease also occur each year. These are usually restricted to particular locations and within these locations, they occur at specific times in the year. This time of the year is commonly referred to as the flu season. Let us have a look at the reasons for such an occurrence.
Why do Flu Seasons occur?
Flu season usually occurs during cold periods in each hemisphere. It is characterized by a marked increase in the number of flu outbreaks. Usually, a particular flu season within the year can be associated with a particular type of influenza virus.
The reason for the increased activity of those viruses, at that period within the year is still unclear. However, some of the researchers have proposed the following reasons for the occurrence of the flu season:
- Individuals are usually indoors during winter. Thus, there is increased contact between them. This increases the chances of transmission of the influenza virus.
- Winter is also characterized by a marked decrease in humidity. This leads to the loss of moisture in mucus, thus reducing the capacity of individuals to keep the virus out of their body.
- Colder temperatures may help the virus in lingering longer on exposed surfaces like table tops, door knobs and other surfaces, that are constantly touched by a number of people.
- The winters are considered to be holiday season in most of the northern hemisphere. Thus, during winter, many individuals travel and visit their relatives etc. leading to an increased risk of the disease.
Some amount of research that has been carried out on guinea pigs shows, that the cold and dry weather supports aerosol transmission by the viruses. These aerosols are fine particles that get suspended in the air, that carry the virus. Inhaling them will give the virus access to a person's body. It has been found that humidity tends to degrade these aerosols and cold weather ensures that the host sheds them for a longer time. This might be another reason for the increase in the number of cases of flu in winter.
Another study that was carried out on the viruses found that the viruses have a coating made of some fat over their bodies. This provides them protection. The coating is hardened in winters and melts only when the viruses enter the respiratory tract. However, in summers the coating may melt in the outer environment, due to the higher temperature.
Some of the researchers have even suggested that the immune response of humans towards flu virus is reduced during winters. However, the truth of this claim is not known.
Precautions to be taken in the Flu Season
The WHO on its part decides the composition of influenza vaccines each year. They are distributed separately each year in the northern and southern hemispheres, just before the onset of the flu season. However, individuals can also take some precautions to protect themselves and their families from flu. These are as follows:
- To be safe, one can take the flu vaccine, especially if there are children in the house. This will significantly reduce the chances of flu.
- One should not ignore any cold or flu-like symptoms. If flu is detected early, it is always easier to cure it. Thus, in case of doubt, you should consult the doctor.
- Individuals should take care of hygiene and they can adapt measures like the ones adapted in Japan, where those infected with flu wear a gauze to prevent its spread.