system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: why can't we alter/use mosquitoes to spread vaccines instead of diseases?

Im not thoroughly versed in the sciences, but if we can engineer viruses and have been able to sequence our own genetic code, why is this not possible, or if it is how could it be done?

first post, Im pretty new to the reddit center of the interwebs.
gpt
Vaccines require a bit more payload than a mosquito can carry, and it isn't likely to be something a mosquito is capable of producing biologically anyway. Furthermore we wouldn't want people to be continually re-exposed to vaccinations every day. If your arm aches after the flu shot imagine how you would feel after being mobbed around the campfire.

Mosquitos also tend to feed from other animals as well. Do we really want your cat to be vaccinated? How about your infant? Random deer and other wild animals? It is easy to see unintended side effects, and without a reliable method of recalling them it would be wildly irresponsible.