How do mosquitoes get sick?

Mosquitoes do not "bite" us, but put their long "straw" like mouthparts into the blood vessels under our skin, and then suck our blood, just like we drink a drink. The reason why we feel itchy is that mosquitoes will inject their saliva into the blood vessels preparing to suck blood while sucking blood. Saliva contains a large number of ingredients. The anticoagulant substances in the saliva can prevent blood from coagulating due to vascular damage. Some ingredients can also dissolve blood cells to facilitate mosquitoes to absorb proteins, so that mosquitoes can have a safe and full meal.

After the mosquito "eats", the immune system in the body will release a protein called "histamine" to fight against foreign substances, and this immune response triggers an allergic reaction at the bite site, so we feel itchy. When blood flows to the bite to speed up tissue recovery, "histamine" will cause the swelling of the tissue around the bite, so there will be a "red envelope". The intensity of this allergic reaction varies from person to person, and some people have a more severe allergic reaction to mosquito bites.

Mosquitoes can serve as transmission vectors for many viral and parasitic diseases. If the mosquito body contains viruses and parasites, the mosquito will inject the pathogen directly into the blood through saliva, making us infected. The main vectors of dengue fever are Aedes aegypti and Aedes albopictus, and Culex tritaorhynchus is the main vector of Japanese encephalitis. For example, after a mosquito with Japanese encephalitis virus bites a person, the virus enters the human body, first proliferates in the mononuclear-phagocyte system, and then enters the blood circulation to form viremia, passes through the blood-brain barrier, invades the central nervous system, and causes brain parenchymal lesions.

In the buzzing season of mosquitoes, if there are many traces of bites on the body, coupled with various recent discomforts, you must pay more attention to whether you have a mosquito-borne infectious disease and consult a regular Junior College doctor.