Manila: The highly contagious respiratory disease Mers-COV has arrived in the Philippines and health authorities are moving quickly to prevent the possible spread of an illness that has killed more than 250 people worldwide.

Health department officials have asked passengers on a recent flight from Saudi Arabia to submit themselves for testing for Middle East Respiratory Syndrome Coronavirus (Mers-COV), after reports that a nurse afflicted with the disease managed to enter the country.

“The Department of Health (DOH) is exerting all efforts to locate all passengers on board a Saudi Airlines flight, including [one who boarded a] domestic flight to South Cotabato,” Health Secretary Enrique Ona said.

He likewise called on all returning overseas Filipino workers who develop symptoms of Mers-COV to cooperate with the government to prevent the spread of the potentially fatal disease.

Reports said two nurses arrived aboard Saudia Airlines flight SV870 from Dammam on August 29. One of them, identified only as “AP” had gone on to fly to her province in South Cotabato aboard Cebu Pacific flight SJ 997 after staying for two days in Metro Manila. The other was identified as CB.

Prior to leaving for the Philippines, both had undergone mandatory testing for fatal disease in the Middle East kingdom. AP, it was found out later on by Philippine health authorities, had tested positive for having the Mers-COV but was still allowed to leave Saudi Arabia as she did not exhibit symptoms of the illness.

Authorities fear that the carrier, AP, could contaminate other people.

The DOH said AP and CB had been fetched by 10 relatives, including two grandchildren.

The entry of the virus in the Philippines could have gone undetected had CB not told authorities.

“Nurse AP stayed with nurse CB until her scheduled flight to her home on August 31. But on September 2, the nurse CB and her two grandchildren developed fever. This prompted the three as well as the others who had welcomed them last August 29, to consult experts and all eventually tested negative for the disease,” DOH said.

CB informed the DOH that AP had earlier tested positive for the respiratory illness in Saudi Arabia. This prompted the DOH to seek AP’s whereabouts. On September 2, AP was reported admitted to the Southern Philippines Medical Centre in South Cotabato.

“She was asymptomatic upon admission. Her specimen was sent to the Research Institute for Tropical Medicine for further testing and confirmation,” the DOH said, adding that the department is not taking any chances.

Asymptomatic means that the disease may not show symptoms.

Until recently, the Philippines has no known local cases of Mers-COV although a Filipina nurse had died in April from the respiratory illness.

According to the DOH, Mers-COV “is a highly fatal respiratory illness presenting an influenza-like illness characterised by fever, cough, and often with diarrhoea.”

Worldwide, reports said some 250 people had died from the disease in some 20 countries.