It's a bit tricky question.

Studies have shown that mosquitoes usually inoculate between 10^4 and 10^6 PFU (plaque forming units) of Virus into humans per bite. Assuming the virus is transmitted into human body through mosquito 10^4 PFU is the quantity of virus that can cause infection in humans (this may later on replicate during the incubation period). But keep in mind that wild virus particles less than this quantity (as low as < 100 virus particles may also lead to infection).

I think your technique should be highly senstitive enough to detect even 5 PFU of virus particles.