A world-leading professor of immunobiology and developmental biology believes COVID-19 could become a seasonal virus, like influenza or the common cold, without a vaccine or therapeutic drugs to lessen its spread.

Speaking to Emma Keeling, from CGTN Europe's RAZOR program, Akiko Iwasaki of the Yale School of Medicine said she expected a secondary post-summer coronavirus spike later in the year when temperatures fall.

"The upcoming winter is going to be another period that we really need to be cautious about," she said.

This is because of the relative humidity of the air we breathe. Viruses don't like humidity, so when we bring cold outside air into our warmer homes in wintertime, the relative humidity drops to 20 or 30 percent. 

This creates ideal conditions for diseases like COVID-19 to thrive, as well as impacting the host's immune response, which works best at humidity levels between 40 and 60 percent.

"That is what allows these respiratory viruses to succeed in transmitting between people during the winter months," said Iwasaki.

The development of vaccines and prophylactic drugs to treat the virus, along with a staggered lifting of social distancing measures, will be vital to avoiding second or even third spikes, even during summer months when COVID-19 can still be transmitted through direct contact or touching hard surfaces.

She added: "I don't see this virus really going away without any interventions. It might ultimately become annual, like seasonal virus infections."

With testing just as vital to suppressing the pandemic, Iwasaki has also developed saliva tests for COVID-19. These are much less invasive than the nasal swabs currently used, which also require healthcare workers to wear PPE while collecting the swabs.

"Saliva is a wonderful specimen for this," she said. "It's so easy to collect that patients can do it themselves. It's also much more sensitive than the nasal swab, so it's more reliable."

Video editor: Pedro Duarte

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