People wearing face masks walk in Osaka, Japan, on April 4, 2021.Chiaki Ueda/The Associated Press
Japanese health authorities are concerned that variants of the coronavirus are driving a nascent fourth wave in the pandemic with just 109 days remaining until the Tokyo Olympics.
The variants appear to be more infectious and may be resistant to vaccines, which are still not widely available in Japan. The situation is worst in Osaka, where infections hit fresh records last week, prompting the regional government to start targeted lockdown measures for one month from Monday.
A mutant COVID-19 variant first discovered in Britain has taken hold in the Osaka region, spreading faster and filling up hospital beds with more serious cases than the original virus, according to Koji Wada, a government adviser on the pandemic.
“The fourth wave is going to be larger,” said Wada, a professor at Tokyo’s International University of Health and Welfare. “We need to start to discuss how we could utilize these targeted measures for the Tokyo area.”
How many coronavirus cases are there around the world?
COVID-19 is caused by a virus called SARS-CoV-2, and as it spread around the world, it mutated into new forms that are more quickly and easily transmitted through small water droplets in the air. Canadian health officials are most worried about variants that can slip past human immune systems because of a different shape in the spiky protein that latches onto our cells. The bigger fear is that future mutations could be vaccine-resistant, which would make it necessary to tweak existing drugs or develop a new “multivalent” vaccine that works against many types, which could take months or years.
Not all variants are considered equal threats: Only those proven to be more contagious or resistant to physical-distancing measures are considered by the World Health Organization to be “variants of concern.” Five of these been found in Canada so far. The WHO refers to them by a sequence of letters and numbers known as Pango nomenclature, but in May of 2021, it also assigned them Greek letters that experts felt would be easier to remember.
ALPHA (B.1.1.7)
- Country of origin: Britain
- Traits: Pfizer-BioNTech and Moderna vaccines are still mostly effective against it, studies suggest, but for full protection, the booster is essential: With only a first dose, the effectiveness is only about 66 per cent.
- Spread in Canada: First detected in Ontario’s Durham Region in December. It is now Canada’s most common variant type. Every province has had at least one case; Ontario, Quebec and the western provinces have had thousands.
BETA (B.1.351)
- Country of origin: South Africa
- Traits: Some vaccines (including Pfizer’s and Oxford-AstraZeneca’s) appear to be less effective but researchers are still trying to learn more and make sure future versions of their drugs can be modified to fight it.
- Spread in Canada: First case recorded in Mississauga in February. All but a few provinces have had at least one case, but nowhere near as many as B.1.1.7.
GAMMA (P.1)
- Country of origin: Brazil
- Traits: Potentially able to reinfect people who’ve recovered from COVID-19.
- Spread in Canada: B.C. has had hundreds of cases, the largest known concentration of P.1 outside Brazil. More outbreaks have been detected in Ontario and the Prairies.
DELTA (B.1.617 AND B.1.617.2)
- Country of origin: India
- Traits: Spreads more easily. Single-dosed people are less protected against it than those with both vaccine doses.
- Spread in Canada: All but a few provinces have recorded cases, but B.C.’s total has been the largest so far.
LAMBDA (C.37)
- Country of origin: Peru
- Traits: Spreads more easily. Health officials had been monitoring it since last August, but the WHO only designated it a variant of concern in June of 2021.
- Spread in Canada: A handful of travel-related cases were first detected in early July.
If I’m sick, how do I know whether I have a variant?
Health officials need to genetically sequence test samples to see whether it’s the regular virus or a variant, and not everyone’s sample will get screened. It’s safe to assume that, whatever the official variant tallies are in your province, the real numbers are higher. But for your purposes, it doesn’t matter whether you contract a variant or not: Act as though you’re highly contagious, and that you have been since before your symptoms appeared (remember, COVID-19 can be spread asymptomatically). Self-isolate for two weeks. If you have the COVID Alert app, use it to report your test result so others who may have been exposed to you will know to take precautions.
Need more answers? Email audience@globeandmail.com
Japan has twice declared a state of emergency that covered most of the country in the past year, most recently just after New Year as the pandemic’s third and most deadly wave struck. Officials are now opting for more targeted measures that allow local governments to shorten business hours and impose fines for noncompliance.
Osaka city cancelled Olympic Torch relay events there, but Prime Minister Yoshihide Suga has insisted Japan will carry out the Games as scheduled. Suga said on Sunday that measures employed in the Osaka area could be expanded to Tokyo and elsewhere if needed.
There were 249 new infections in Tokyo on Monday, still well below the peak of over 2,500 in January. In Osaka, the tally was 341, down from a record 666 cases on Saturday.
The true extent of the mutant cases is unknown, as only a small fraction of positive COVID-19 cases undergo the genomic study necessary to find the variants.
A health ministry report last week showed 678 cases of variants from Britain, South Africa, and Brazil had been discovered nationwide and at airports, with the biggest clusters in Osaka and nearby Hyogo prefecture.
Those three all have the N501Y mutation, and the latter two also have the E484K mutation. Authorities in Japan have found more than 1,000 cases that only have E484K.
That variant was present in about 70 per cent of coronavirus patients tested at a Tokyo hospital last month, Japanese public broadcaster NHK said on Sunday.
The rebound in cases came within weeks of the government lifting state of emergency measures, and the priority measures being rolled out now are intended to halt an unexpected rise in mutant cases, said Makoto Shimoaraiso, a Cabinet Secretariat official for Japan’s COVID-19 response.
“We take the criticism when people say that we have not been able to detect any variants,” he said.
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