Covid antigen spit (saliva) test for international flights to Ecuador

I was unable to get vaccinated based on my health history.

I need to make a trip to the US. Regarding my return flight to Ecuador, are antigen spit (saliva) tests currently being offered by labs in the US, with a 24 hour or less turnaround time. And will it be accepted by the airlines and Ecuador?

I prefer to avoid having a testing swab in my nose or throat

Many thanks,

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