Having mostly dodged the COVID-19 pandemic until now, Papua New Guinea reported Thursday it had detected three new cases in the previous 24 hours, bringing the total to 30 -- up from just 11 on Sunday.

With limited coronavirus testing and many positive cases found in health workers, there are fears the virus may have a stronger foothold than those detected cases may indicate.

National pandemic response controller David Manning expressed "serious concerns on the alarming rate of increase of COVID-19 cases in Port Moresby and the likely spread to the other provinces", saying there was a "high likelihood of expanded community transmission".

Papua New Guinea is one of the poorest countries in the Pacific. Its rickety health system is already under severe pressure from the widespread transmission of malaria, tuberculosis and HIV/AIDS, as well as one of the world's few remaining outbreaks of polio.

Manning added that the WHO was in the process of mobilizing international emergency medical teams to deploy to the country.

He said in a statement there was "an urgent need" for emergency health workers to help the country manage a surge in cases and administer isolation facilities.

"We are also discussing with the PNG Defense Force to assist... the Health Department. We have always said we don't have adequate facilities."

Manning admitted testing had been "very limited" in areas outside the capital, and "while there is no evidence of hospitals being overwhelmed", that could "be due to delayed reporting or poor health checking behavior".