How are viral infections caused?
Disease description:
Recently, my child has had a fever for two consecutive days and it hasn't improved. After going to the hospital for a checkup, the doctor said it was a viral infection. I would like to ask, what causes a viral infection?
Doctor's answer (1)
Dr. Yang Ziqi
There are many types of viruses, including RNA viruses (such as influenza viruses, coronaviruses) and DNA viruses (such as HPV, hepatitis B virus). They can enter the human body through the following routes:
1. Contact transmission: Direct contact with bodily fluids (e.g., saliva, nasal mucus, blood) from an infected individual, or by touching surfaces contaminated with virus and then touching one's own mouth, nose, or eyes.
2. Airborne transmission: Certain viruses, such as influenza viruses, can spread through droplets released into the air when an infected person coughs or sneezes, which can then be inhaled by others.
3. Food and water: Consuming food or water contaminated with virus—for example, norovirus commonly spreads through this route.
4. Mother-to-child transmission: If a pregnant woman is infected with certain viruses (such as rubella virus or cytomegalovirus), the virus can be transmitted to the fetus through the placenta.
If symptoms of viral infection occur, prompt medical attention is recommended.
