question about aids,and mosquitos?

The results of experiments and observations of insect biting behavior indicate that when an insect bites a person, it does not inject its own or a previously bitten person's or animal's blood into the next person bitten. Rather, it injects saliva, which acts as a lubricant so the insect can feed efficiently. Diseases such as yellow fever and malaria are transmitted through the saliva of specific species of mosquitoes. However, HIV lives for only a short time inside an insect and, unlike organisms that are transmitted via insect bites, HIV does not reproduce (and does not survive) in insects. Thus, even if the virus enters a mosquito or another insect, the insect does not become infected and cannot transmit HIV to the next human it bites.

There also is no reason to fear that a mosquito or other insect could transmit HIV from one person to another through HIV-infected blood left on its mouth parts. Several reasons help explain why this is so. First, infected people do not have constantly high levels of HIV in their blood streams. Second, insect mouth parts retain only very small amounts of blood on their surfaces. Finally, scientists who study insects have determined that biting insects normally do not travel from one person to the next immediately after ingesting blood. Rather, they fly to a resting place to digest the blood meal.

> Abstract: Public concern about the risk of HIV transmission from mosquito
>bites persists. However, research has shown that HIV does not survive or
>replicate in the arthropod vector, and arthropods are unable to transmit
>the virus from an infected host to an uninfected one. Additionally, an
>epidemiologic study found no relationship between HIV infection and
>exposure to mosquitoes. [Infect Med 14(5):353-354, 1997. © 1997 SCP
>Communications, Inc.]
[....]


>Within minutes of being fed blood contaminated with 5 x 104 TCID/mL of
>HIV, stable flies (Stomoxy calcitrans) regurgitated 0.2mcL of fluid
>containing ~ 10 TCID.[4] The minimum infective dose for humans
>contaminated in this manner is unknown, but under conditions such as those existing in tropical countries with large populations of biting insects
>and a high prevalence of HIV infection, transfer might theoretically be
>possible, although highly unlikely.