Mosquitoes only suck blood from healthy people.

Mosquitoes can spread diseases in two ways: biological transmission and mechanical transmission. The so-called biological transmission means that pathogens go through various stages of development and proliferation in mosquitoes and then spread to people. For example, after Japanese encephalitis virus is inhaled into mosquitoes with blood, it first proliferates in their intestines, then moves to salivary glands and spreads to people or animals after biting. HIV does not develop or multiply in mosquitoes, so it is impossible to spread by biological means. The mechanical transmission of AIDS is not feasible. Because before sucking blood, mosquitoes spit saliva from the saliva tube (as a lubricant for sucking blood), and then suck blood from another tube-esophagus. The blood is inhaled in one direction and will not be spit out by the esophagus after inhalation. Some people worry that the blood left on the mouth of mosquitoes may carry HIV, which will be transmitted to people. However, some studies have found that the blood left on the mouth of mosquitoes is only 0.00004 ml. According to this calculation, it takes 2800 bites to carry enough virus to cause HIV infection. Moreover, when the blood with HIV is inhaled by mosquitoes, HIV will be digested, destroyed and completely disappeared by mosquitoes within 2-3 days. But once mosquitoes have sucked enough blood, they won't bite until they are completely digested. Therefore, no matter from which aspect, the possibility of mosquitoes spreading AIDS can be said to be non-existent. So far, there are no reports of HIV infection due to mosquito bites. Mosquitoes can spread diseases in two ways: biological transmission and mechanical transmission. The so-called biological transmission means that pathogens go through various stages of development and proliferation in mosquitoes and then spread to people. For example, after Japanese encephalitis virus is inhaled into mosquitoes with blood, it first proliferates in their intestines, then moves to salivary glands and spreads to people or animals after biting. HIV does not develop or multiply in mosquitoes, so it is impossible to spread by biological means. The mechanical transmission of AIDS is not feasible. Because before sucking blood, mosquitoes spit saliva from the saliva tube (as a lubricant for sucking blood), and then suck blood from another tube-esophagus. The blood is inhaled in one direction and will not be spit out by the esophagus after inhalation. Some people worry that the blood left on the mouth of mosquitoes may carry HIV, which will be transmitted to people. However, some studies have found that the blood left on the mouth of mosquitoes is only 0.00004 ml. According to this calculation, it takes 2800 bites to carry enough virus to cause HIV infection. Moreover, when the blood with HIV is inhaled by mosquitoes, HIV will be digested, destroyed and completely disappeared by mosquitoes within 2-3 days. But once mosquitoes have sucked enough blood, they won't bite until they are completely digested. Therefore, no matter from which aspect, the possibility of mosquitoes spreading AIDS can be said to be non-existent. So far, there are no reports of HIV infection due to mosquito bites.