Influenzavírusok

Influenzavírusok, commonly known as influenza viruses, are a genus of RNA viruses that cause influenza, a highly contagious respiratory illness in humans and other animals. There are three main types of influenza viruses that infect humans: type A, type B, and type C. Type A viruses are the most common and can cause pandemics. Type B viruses are also common and cause seasonal epidemics, while type C viruses typically cause mild respiratory illness and do not cause epidemics.

Influenza viruses are constantly changing, a process called antigenic drift. This is why new influenza vaccines are developed each year. Occasionally, a major change can occur in the influenza A virus, called antigenic shift. This can lead to a pandemic because the human population has little or no immunity to the new virus.

Transmission of influenza viruses occurs primarily through droplets expelled when an infected person coughs, sneezes, or talks. These droplets can be inhaled by people nearby or land on surfaces, which can then be touched by others who then touch their mouth, nose, or eyes. Symptoms of influenza typically include fever, cough, sore throat, muscle aches, headache, and fatigue. While most people recover within a week or two, influenza can lead to serious complications such as pneumonia, bronchitis, sinus infections, and ear infections, and can be life-threatening for certain groups, including young children, older adults, pregnant women, and people with chronic medical conditions.

Preventive measures include vaccination, good hygiene practices such as frequent handwashing, and avoiding close contact with sick individuals. Antiviral drugs can be used to treat influenza, reducing the severity and duration of illness, and preventing complications.