JointHealth™ express   July 30, 2021

COVID-19 Update: What is the COVID-19 Delta variant, why is it spreading so fast, and are existing vaccines effective against it?

At the same time Canadian provinces slowly re-open, there is an alarming surge in coronavirus cases worldwide -- and health experts say a key factor in this latest wave is the highly contagious Delta variant.

According to the World Health Organization (WHO), the Delta variant is spreading about 60% faster than the “Alpha” strain first identified in the United Kingdom late last year. The Delta variant was discovered in India last December and has now become the most dominant strain of the COVID-19 virus in the world, spreading to at least 98 countries and causing outbreaks in areas of countries with low vaccination rates.

According to David Fisman, epidemiologist and professor at the University of Toronto: “The Delta variant is about 2.6 times more contagious than the original strain of COVID-19. This means it will cause larger pandemics and be more difficult to control.” He added: “We find that patients with the Delta strain are three times more likely to go to intensive care and twice as likely to die than patients with the original strain of COVID-19.”

The symptoms of a COVID-19 infection from the Delta variant do not appear to be the same as those from the initial strain of the virus. Loss of smell no longer seems to be one of the main symptoms.

“The symptoms are more like the flu, Fisman said. “Right now, in the northern hemisphere, there isn’t influenza, so if anyone has flu-like symptoms, it’s likely COVID-19.”

Does Delta cause different COVID-19 symptoms?

Maybe. Some doctors and public health departments have reported that people infected with Delta have different symptoms from the original, classic signs of COVID-19: cough, loss of taste or smell, and fever. Now, some of the more common symptoms appear to be runny nose, sore throat and headache, according to the ZOE COVID Study, an ongoing app-based research project based in the U.K.

Who is being affected by the Delta variant?

The hotspots for the Delta variant are generally in areas where vaccination rates are low. And health officials are once again urgently pressing unvaccinated people to get the COVID-19 shot.

"This is becoming a pandemic of the unvaccinated," said the U.S. Center for Disease Director Dr. Rochelle Walensky. "If you remain unvaccinated, you are at risk."

But if you're already vaccinated, how worried should you be? Are new precautions called for? Here's what to know about the fast-spreading variant and how to stay safe and protect others.

Should I go back to COVID prevention practices?

Many health experts say that wearing a mask again in public may be a smart move, especially for immunocompromised/immunosuppressed individuals who are fully vaccinated when they are going to be in indoor settings, like grocery stores, movie theatres and offices, with people who may be unvaccinated and unmasked.

Remember the primary way the Delta variant spreads, like earlier strains, remains being indoors with someone who is infected and breathing in their droplets or aerosols. With Delta, the difference is that the infected person will make many more copies of the virus, faster, which makes it easier to spread.

And keep in mind that children can get infected and spread Delta. Although children tend to have more mild cases of coronavirus, they are certainly susceptible to infection. Children remain the least protected age group, since the vaccine is not authorized for children under the age of 12.

If I'm vaccinated, can I get sick with the Delta variant?

Yes, but don't panic. Although there are breakthrough cases (when fully vaccinated person gets infected with the coronavirus), people who are fully vaccinated rarely become very sick. Experts say the shots are very good at reducing the risk of serious illness that leads to hospitalization or death.

A study, published in the New England Journal of Medicine on July 21, 2021, found two doses of Pfizer or AstraZeneca's COVID-19 vaccine are nearly as effective against the highly transmissible Delta coronavirus variant as they are against the previously dominant Alpha variant - though the study reiterated that one shot of the vaccines is not enough for high protection.

The British study found that two doses of Pfizer's shot was 88% effective at preventing symptomatic disease from the Delta variant, compared to 93.7% against the Alpha variant.

Two shots of AstraZeneca vaccine were 67% effective against the Delta variant, up from 60% originally reported, and 74.5% effective against the Alpha variant, compared to an original estimate of 66% effectiveness.

The most important thing you can do to prevent getting the Delta variant

Get vaccinated and encourage others who are not vaccinated to get the shot.

About 80 per cent of eligible Canadians have received at least one dose of a vaccine, and about 54 per cent are fully vaccinated. Polls suggest 10 per cent of Canadians are immovably opposed to vaccines, while 10 per cent are hesitant, or simply not in a rush. However, time is not on our side, according to Rodney Russell, a professor of immunology and virology at Memorial University of Newfoundland and editor-in-chief of the journal Viral Immunology: “This virus spreads so fast, and is so contagious that, if 20 per cent of the population is not vaccinated, that will be more than enough to keep this thing going and give it the opportunity to keep mutating.”