A 57-year-old Singaporean woman has been diagnosed with dengue and Covid-19 at the same time.

This is the first such rare case to have emerged in Singapore, the Ministry of Health (MOH) said on Feb. 20.

All other patients who had been warded with the woman when she was admitted as a dengue patient are now quarantined at Ng Teng Fong General Hospital, as a result of the woman's subsequent coronavirus diagnosis.

The double-virus sufferer is case 82, MOH said.

What happened

The woman visited the hospital on Feb. 13 and Feb. 15.

She was admitted as a dengue patient in a general ward on the second visit.

There was no misdiagnosis, MOH said, and her symptoms and laboratory results were consistent with dengue.

She was tested for the coronavirus disease when she developed respiratory symptoms.

On Tuesday afternoon, Feb. 18, tests confirmed she had Covid-19, and was immediately transferred to an isolation room.

Difficulties in diagnosis

MOH said there is nothing in the literature so far to suggest having dengue and Covid-19 simultaneously can lead to complications.

It is understood that there are difficulties in diagnosing dengue from Covid-19 in the early stages of the diseases -- within the first few days -- as both are acute viral infections.

Both ailments can display symptoms that overlap.

MOH also pointed out that one does not cause the other.

A common characteristic is that the sufferer of dengue and Covid-19 would go down with a sudden persistent high viral fever that would not go away after three to five days.

But those with dengue usually have fever and rash, and will not develop respiratory symptoms.

Respiratory symptoms associated with the coronavirus disease include cough, runny nose and sore throat.

There are, at the moment, no specific treatments for the majority of common viral infections, with the exception of influenza, which kills more people than the new coronavirus.