bekky <smeggin at ihug.com.au> wrote in message
news:7kg9hb$jm7$1 at toto.tig.com.au...
> Hello,
> Can any one tell me why H.I.V or hepatitis ect is not spread
by
> mosquitos?
> Thanks, Ben
>>> Generally for a virus to be transmitted by a mosquito it must replicate in
the host mosquito cells to a high titre to ensure effective infection of the
next host after the mosquito bite.
For instance, the yellow fever virus replicates in the gut of the mosquito
vector and then passes to the salivary gland of the mosquito. It is then
transmitted to the new host as the mosquito injects saliva during the bite
to ensure an effective blood flow.
In the case of HIV and Hep B the virus cannot replicate in the mosquito. In
that case transmission can only occur if the mosquito acts as a flying
hypodermic. HIV is very labile and will become inactive after a short time
outside the body. Hep B is more stable but as a mosquito will not feed
again for some time after a blood meal (if at all - it is only female
mosquitoes that bite - they need the extra nutrients in the blood to produce
eggs) it is unlikely that any active virus would be present during the next
meal.
Any further questions? Please do not hesitate to call.
Regards,
Geoff Crawford
--
Dr Geoff Crawford
Access Academix
89 Dellfield Drive
Templestowe VIC 3106
Australia
Phone +61 3 981 272 80
Mobile +61 412 599 649
Email access_academix at optusnet.com.au
