Can mosquitoes transmit Human Immunodeficiency Virus (HIV)?

Mosquitoes Cannot Transmit HIV

Mosquitoes cannot transmit HIV (Human Immunodeficiency Virus) to humans. 1 The scientific evidence conclusively demonstrates that HIV transmission via mosquito bites is virtually impossible.

Why Mosquitoes Cannot Transmit HIV

There are several biological and epidemiological reasons why mosquitoes cannot serve as vectors for HIV:

1. No Viral Replication in Mosquitoes

   • HIV cannot replicate inside mosquitoes, bed bugs, fleas, or other blood-sucking insects 1
   • The virus requires human T4 lymphocytes to replicate, which are absent in mosquito cells 1
   • Studies with bedbugs (Cimex hemipterus) and mosquitoes (Toxorhynchites amboinensis) show no evidence of HIV replication after exposure to the virus 2

2. Limited Virus Survival

   • HIV has very short survival time in mosquitoes - the virus does not persist long enough to allow transmission 1
   • In experimental studies, HIV survived in Cimex lectularius (bedbugs) for only up to 4 hours and in Aedes aegypti mosquitoes showed no survival at all 3

3. Biological Barriers

   • Unlike viruses that are transmitted by mosquitoes (such as Yellow Fever Virus), HIV does not infect mosquito salivary glands 4
   • Mosquito-transmitted viruses like Yellow Fever require specific biological cycles within the mosquito that HIV cannot undergo 4

4. Low Concentration in Blood

   • HIV appears in much lower concentrations in human blood compared to viruses that are successfully transmitted by mosquitoes 1
   • The low viral titer makes mechanical transmission extremely unlikely 1

Comparing to Known Mosquito-Transmitted Viruses

Viruses that are successfully transmitted by mosquitoes, such as Yellow Fever Virus (YFV), have specific characteristics that HIV lacks:

• YFV can replicate in mosquitoes and infect their salivary glands 4
• YFV establishes specific transmission cycles between mosquitoes and vertebrate hosts 4
• YFV produces high levels of viremia in humans, making them infectious to mosquitoes 4

Experimental Evidence

Multiple laboratory studies have attempted to demonstrate HIV transmission via insects and all have failed:

• Experiments with bedbugs fed on HIV-infected blood showed that while the virus could be detected for up to 8 days, no viral replication occurred 2
• Four separate attempts to transmit HIV by interrupted feeding of bedbugs from infected to uninfected blood all failed 3
• Mechanical transmission of HIV by bedbugs could not be demonstrated even in controlled laboratory conditions 2

Conclusion

Based on multiple lines of scientific evidence, the risk of HIV transmission via mosquito bites is effectively zero. The biological requirements for either mechanical or biological transmission of HIV by mosquitoes are not met. This conclusion is supported by epidemiological patterns of HIV spread, which correspond to known routes of transmission (sexual contact, blood exposure, and mother-to-child transmission) rather than patterns typical of mosquito-borne diseases.