2013
JF-Expert Member
- Aug 2, 2011
- 11,358
- 6,059
Mosquitoes suck whole blood together with all its contained viruses, bacteria and other pathogens, including HIV. Luckily for humans, the HIV virus cannot be spread by mosquitoes.
This is because of several reasons accounting for the inability of mosquitoes to transmit HIV.
First of all, the feeding mechanism of mosquitoes does not promote transmission, it is not like a hypodermic needle injecting blood .
The sucking "snout" of a mosquito has six mouthparts. Four of these are used for piercing the skin that the mosquito is biting. The other two mouth parts consist of two tubes. One tube sends saliva into the host and the other sends blood up into the mosquito.
This two tube system does not allow for mixing. It is one major reason why mosquitoes are unable to transmit HIV. Only saliva is injected into humans when a mosquito bites and thus HIV positive blood that a mosquito may have previously ingested is never transmitted to other humans.
In addition, unlike with mosquito borne diseases, HIV is unable to replicate within the mosquito's gut. This is because the receptors that HIV requires to replicate are not present in mosquitoes. In humans, HIV must bind to CD4 T cells and the CCR5 or the CXCR4 co-receptors to begin replicating. No such cells and co-receptors exist inside the mosquito's gut. Thus, the virus has no way of replicating or migrating to the mosquito's salivary glands. Instead, HIV particles are digested by the mosquito alongside its blood meal. During this digestion process, HIV particles are completely destroyed.
Finally, mosquitoes suck only 0.0005 ml of blood per meal. There is very little virus in that volume. Coupled with the unique feeding mechanism of mosquitoes described above, it would take about ten million mosquito bites to transmit one unit of HIV.
Kwa kiswahili tafsiri isiyorasmi ni kwanini Mbu haambukizi virusi vya UKImwi.
1. Mbu hana mdomo mfani wa sindano hizi za kuchomea binadamu.
Mbu ana sehemu 6 za midomo yake zilizojitenga. 4 kazi yake ni kutoboa ngozi ya binadamu. Zilizobaki 2, zipo kama tyubu, moja inatoa 'mate' na nyingine ina nyonya damu. Haziruhusu kuchanganyika. Kinachoingizwa kwa binadamu ni Mate pekee.
2. HIV hawawezi kuzaliana wakaongezeka kwenye mfumo wa tumbo la mbu. Kwasababu vipokezi(Receptors) vya kirusi havipo kwenye mwili wa Mbu.
Kwa binadamu HIV inashikana na CD4 T cells na CCR5 au CXCR4 co-receptors ili kuweza kutengeneza virusi zaidi. Hakuna seli kama hizo na vipokezi visaidizi (co-receptors) kwenye mfumo wa chakula wa mbu.
Hivyo HIV haziwezi kwenda kwenye tezi za mate za mbu. mbu anavimengenyana vipande vya HIV pamoja na damu kama mlo na kuviharibu kabisa.
3. Mwisho. Mbu ana nyonya damu mililita 0.0005 za damu kwa mlo mmoja. Kuna virusi kidogo sana katika ujazo wa damu hii. Itawahitaji mbu milioni 10 ili kuweza kusafirisha uniti moja ya HIV.
This is because of several reasons accounting for the inability of mosquitoes to transmit HIV.
First of all, the feeding mechanism of mosquitoes does not promote transmission, it is not like a hypodermic needle injecting blood .
The sucking "snout" of a mosquito has six mouthparts. Four of these are used for piercing the skin that the mosquito is biting. The other two mouth parts consist of two tubes. One tube sends saliva into the host and the other sends blood up into the mosquito.
This two tube system does not allow for mixing. It is one major reason why mosquitoes are unable to transmit HIV. Only saliva is injected into humans when a mosquito bites and thus HIV positive blood that a mosquito may have previously ingested is never transmitted to other humans.
In addition, unlike with mosquito borne diseases, HIV is unable to replicate within the mosquito's gut. This is because the receptors that HIV requires to replicate are not present in mosquitoes. In humans, HIV must bind to CD4 T cells and the CCR5 or the CXCR4 co-receptors to begin replicating. No such cells and co-receptors exist inside the mosquito's gut. Thus, the virus has no way of replicating or migrating to the mosquito's salivary glands. Instead, HIV particles are digested by the mosquito alongside its blood meal. During this digestion process, HIV particles are completely destroyed.
Finally, mosquitoes suck only 0.0005 ml of blood per meal. There is very little virus in that volume. Coupled with the unique feeding mechanism of mosquitoes described above, it would take about ten million mosquito bites to transmit one unit of HIV.
Kwa kiswahili tafsiri isiyorasmi ni kwanini Mbu haambukizi virusi vya UKImwi.
1. Mbu hana mdomo mfani wa sindano hizi za kuchomea binadamu.
Mbu ana sehemu 6 za midomo yake zilizojitenga. 4 kazi yake ni kutoboa ngozi ya binadamu. Zilizobaki 2, zipo kama tyubu, moja inatoa 'mate' na nyingine ina nyonya damu. Haziruhusu kuchanganyika. Kinachoingizwa kwa binadamu ni Mate pekee.
2. HIV hawawezi kuzaliana wakaongezeka kwenye mfumo wa tumbo la mbu. Kwasababu vipokezi(Receptors) vya kirusi havipo kwenye mwili wa Mbu.
Kwa binadamu HIV inashikana na CD4 T cells na CCR5 au CXCR4 co-receptors ili kuweza kutengeneza virusi zaidi. Hakuna seli kama hizo na vipokezi visaidizi (co-receptors) kwenye mfumo wa chakula wa mbu.
Hivyo HIV haziwezi kwenda kwenye tezi za mate za mbu. mbu anavimengenyana vipande vya HIV pamoja na damu kama mlo na kuviharibu kabisa.
3. Mwisho. Mbu ana nyonya damu mililita 0.0005 za damu kwa mlo mmoja. Kuna virusi kidogo sana katika ujazo wa damu hii. Itawahitaji mbu milioni 10 ili kuweza kusafirisha uniti moja ya HIV.
