Cases of the Omicron variant of the coronavirus popped up in countries on opposite sides of the world Sunday and many governments rushed to close their borders even as scientists cautioned that it’s not clear if the new variant is more alarming than other versions of the virus.
The variant was identified days ago by researchers in South Africa, and much is still not known about it, including whether it is more contagious, more likely to cause serious illness, or more able to evade the protection of vaccines. But many countries rushed to act, reflecting anxiety about anything that could prolong the pandemic that has killed more than 5 million people.
Israel decided to bar entry to foreigners, and Morocco said it would suspend all incoming flights for two weeks starting Monday, among the most drastic of a growing raft of travel curbs being imposed by nations around the world as they scrambled to slow the variants spread. Scientists in several places, from Hong Kong to Europe to North America, have confirmed its presence. The Netherlands reported 13 Omicron variant cases on Sunday, and both Canada and Australia each found two.
Noting that the variant has already been detected in many countries and that closing borders often has limited effect, the World Health Organization called for frontiers to remain open.
Dr. Francis Collins, director of the National Institutes of Health in the United States, meanwhile, emphasized that there is no data yet that suggests the new variant causes more serious illness than previous COVID-19 variants.
Collins echoed several experts in saying the news should make everyone redouble their efforts to use the tools the world already has, including vaccinations, booster shots and measures such as mask-wearing.
The Dutch public health authority confirmed that 13 people who arrived from South Africa on Friday have so far tested positive for omicron. They were among 61 people who tested positive for the virus after arriving on the last two flights to Amsterdam’s Schiphol airport before a flight ban was implemented. They were immediately put into isolation, most at a nearby hotel.
Canada’s health minister says the country’s first two cases of omicron were found in Ontario after two individuals who had recently traveled from Nigeria tested positive.
Authorities in Australia said two travelers who arrived in Sydney from Africa became the first in the country to test positive for the new variant. Arrivals from nine African countries are now required to quarantine in a hotel upon arrival. Two German states reported a total of three cases in returning travelers over the weekend.
Many countries are introducing such bans, though they go against the advice of the WHO, which has warned against any overreaction before the variant is thoroughly studied.