Half the people who catch COVID may suffer long-term changes to their senses, according to preliminary studies, Daily Mail reported.

Researchers at the Karolinska Institute in Stockholm ran tests on 100 people who had lost their sense of smell after a bout of COVID in March 2020 and found that 18 months on, almost one in 20 had regained nothing whatsoever, the report said.

Previous research suggested a similar number were still suffering this deceptively unpleasant symptom six months after recovering from their initial illness. But the newly published findings indicate that, in a significant minority, it may endure even longer.

Along with a fever and cough, it is one of the defining and most surprising characteristics of COVID19: the loss of your sense of smell. It's usually accompanied by an inability to taste anything, as the two senses are intrinsically linked. In many cases the problem resolves itself in a matter of weeks, the report said.

Loss of smell or taste is not an uncommon symptom for people suffering from respiratory viruses such as colds and flu. This is partly because swelling in the throat and nose can disrupt smell and taste receptors. But sometimes the viruses can also damage small nerves in the nasal passage, drastically reducing sensation even after the virus has left the body.