LONDON: A Japanese expert on Wednesday called on people to stay vigilant against a possible second wave of new coronavirus infections in which the viruses are likely to become more virulent.

“Continued human-to-human transmission promotes the survival of viruses that easily increase inside human bodies,” Hiroshi Kida, distinguished visiting professor at Hokkaido University’s Research Center for Zoonosis Control, said in an online seminar held by Jiji Press’ London bureau. “There is a possibility that the viruses become highly pathogenic.”

Kida is known as a leading expert of influenza studies.

“It has almost become common scientific knowledge that influenza viruses causing pandemics, such as the so-called Spanish flu, turn more virulent in second and third waves of infections or after they become seasonal,” Kida said.

Noting that the number of people contracting COVID-19 is surging in South America and India, Kida said, “There are no national borders for infectious diseases.”

“We need to remain alarmed as long as there is a virus outbreak anywhere on Earth,” Kida added.

Kida has also been serving as head of the World Health Organization’s Collaborating Center for Zoonoses Control since 2011.

JIJI Press