COPENHAGEN - The World Health Organization (WHO) on Thursday reiterated its warning that children can also be affected by the new coronavirus, which has claimed the lives of several young people.

"The very notion that 'COVID-19 only affects older people' is factually wrong," the head of the WHO's European branch, Hans Kluge, told reporters during an online briefing from Copenhagen.

"Age is not the only risk for severe disease," Kluge insisted.

Severe cases have been reported among teens and young adults, with some requiring intensive care and several deaths, he said.

In Europe, the youngest victim is a 12-year-old girl who died in Belgium. In the United States, a six-week-old baby has died from the virus.

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Some 10 to 15 percent of cases detected in people under the age of 50 were a moderate to serious infection, according to the WHO.

However, Kluge noted that "people who age healthily are less at risk."

"There are reports of people over the age of 100 who were admitted to hospital for COVID-19 and have now since made a complete recovery."

The WHO's Europe branch said there were 464,859 confirmed cases of COVID-19 and 30,098 deaths in the 53 countries that make up its region.

Some 80 percent of those who died from the virus had at least one underlying illness, in particular cardiovascular disease and diabetes.

Kluge said it was of utmost importance "for every age group" to respect hygiene guidelines.

"It is not only an act of solidarity with others, in particular with those most likely to be severely affected, but also vital for your own health and safety."