Coronavirus: Hidden sign you might be infected

If you suddenly lose your sense of smell, you may be exhibiting the first sign of coronavirus, scientists believe.

Medical employees wait to carry out tests at a coronavirus test centre in Germany. Picture: AFP.

If you suddenly lose your sense of smell, you may be showing an early sign of coronavirus, according to medical specialists.

Ear, nose and throat surgeons say the virus causes swelling in the olfactory mucosa, which causes a loss of smell. The sign could be used as a key clinical indicator in otherwise symptom-free carriers of COVID-19.

As cases in Australia rose to 1887, with a rise of 149 in NSW alone, early detection, and detection in otherwise symptom free carriers is becoming increasingly urgent.

“It is these silent carriers who may remain undetected by current screening procedures, which may explain why the disease has progressed so rapidly in so many countries around the world,” Flinders University professor and ENT specialist Simon Carney said.

“While further research is required, loss of smell, or anosmia, has been reported in as many as one in three patients in South Korea and in Germany, this figure was as high as one in two.”

There is a major international effort to find a vaccine for coronavirus, with pharmaceutical companies co-operating in the race for vaccination as global deaths reach over 16,000. However the earliest date one could be available is a year to 18 months away.

Because the virus has come from animals before mutating to human to human transmission, we have no natural or acquired immunity to it, as we do with the common cold and the flu.

The known symptoms are similar to flu symptoms – a sore throat, runny nose and lethargy. But scientists are only just beginning to recognise other, hidden symptoms.

Experts remain puzzled as to why children don’t seem to suffer from the virus. Many believe they carry it and may have become super-spreaders. In Italy, one reason for the sudden rise in cases was that when schools closed, parents sent their children to be looked after by grandparents. The children unknowingly passed on the virus to their grandparents, who became sick in huge numbers.

Cases in Italy have finally begun slowing, with data released by Italy’s Civil Protection agency overnight (AEDT) showed 4,789 new cases from a day earlier, nearly 700 fewer than the figure reported Sunday. The number of deaths also did not rise by as much. There were just over 600 registered on Monday compared to 651 on Sunday.

However in Britain where cases are still rising, an ENT professor in London also reported a dramatic increase in patients with anosmia as their only symptom of COVID-19 infection.

Professor Carney said Australia was in a position to take advantage of these findings overseas to try and lower the rate of infection.

He said doctors and COVID-19 detection centres could use the subtle sign as part of their testing criteria and patients should also consider calling their GP if they notice this symptom.