Global health challenges

Seasonal influenza

Seasonal influenza

Influenza or ‘flu’ is a contagious viral infection caused by smart viruses. It can cause mild to severe illness, and at times, death. We help preventing it.

Flu occurs annually, causing serious consequences among the high risk groups, such as the elderly, young children, and those with certain chronic conditions. According to the World Health Organization (WHO), it is estimated that 5-10% of adults and 20-30 % of children 10 to 20 % worldwide of the world population are affected each year.

There are three different ways to produce flu vaccines:

  • the egg-based flu vaccine which is the most common,
  • cell-based flu vaccine, and
  • recombinant flu vaccine.

Flu viruses are spread mainly by droplets made when people with flu cough, or catch it from contaminated surfaces. Disease spreads very quickly especially in crowds. The virus spreads fastest at low relative humidity and low temperatures, therefore seasonal epidemics tend to appear in winter. Influenza A strains result in greater contagion and deaths, while influenza B is usually associated with lower spread rates and milder disease cases. Occasionally, however, influenza B can cause serious epidemics, similar to type A viruses. Type B influenza can only affect humans, particularly children.

Seasonal epidemics influenza spreads quickly and causes high healthcare costs as well as seriously decreases people’s productivity. The incubation time for influenza can vary from one to five days and typically causes fever, cough, sore throat, muscle pain, runny nose, and loss of appetite.

Each year in September and February respectively, the WHO Global Influenza Program announces the influenza strains for production of the next seasonal vaccines. The disease season generally begins in May–June in the southern hemisphere and in November–December in the northern hemisphere. The identification of strains is based on surveillance data from the worldwide network of National Influenza Centres and WHO Collaborating Centres.

Here is precisely where our manufacturers get into the picture. They make the flu vaccines, in a fast-moving process that can take up to 30 weeks, since large quantities of vaccines are needed. Several quality controls are conducted on the way to the final vaccine. Flu vaccines cause antibodies to develop in the body about two weeks after vaccination. These antibodies provide protection against infection with the viruses that are in the vaccine.

Recent data confirms dip in flu vaccine uptake. This trend is alarming given the potential of flu vaccines to substantially reduce the annual disease burden and given their proven safety. The underuse of flu vaccines is a serious public health concern that needs to be addressed. Our flu vaccines work. The best way to prevent the flu is by getting vaccinated each year.

5 million

cases of severe illness yearly (WHO)

20 - 30 %

children affected yearly (WHO)

5 - 10 %

adults affected yearly (WHO)

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