Some passengers have raised concerns that there are discrepancies in the outcome of such tests at the airport.
But the health authorities said the testing procedure meets all international standards and is constantly being monitored by the Foods and Drugs Authority (FDA).
The Health Service in a statement said
"Ms. Mavis Boateng in the viral video made a lot of allegations including the fact that she presented a negative PCR test from her country of origin and as such, she alma test positive on arrival."
"It is worth noting that a person can present a negative PCR test on arrival and still test positive at KIA because he or she may be incubating the virus. Also, your test result status is specifically with reference to the date of doing the test, so any risky activities alloy/anis can change your status."
It added: "she also made an allegation that test/result at KIA is fake. This is also not true because the test conducted at KIA meets all international standards and is constantly being monitored by the Food and Drugs Authority (FDA)."