Economy 17 August 2021, 12:35pm

Vaccines effective against Delta variant, ensures Hungarian virus expert Rusvai

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The currently available vaccines offer good protection against the Delta variant of coronavirus. Once you are vaccinated, chances are low that you contract the virus and die or require mechanical ventilation, said virus expert Miklós Rusvai.

Rusvai told commercial broadcaster RTL Klub late on Monday that if 100 people inoculated with Pfizer-BioNTech’s vaccine get infected with the Alpha (UK) variant, then 92 of them will beat the infection with mild symptoms or no symptoms at all, while 8 of them could run a fever and have runny noses.

If they are infected with the Delta variant, none of them will die or get so sick that will need artificial ventilation, but about 15 of them will have symptoms, added Rusvai.

Vaccines vs. Delta variant

The vaccines developed by Pfizer-BioNTech, Moderna and Johnson & Johnson are all proven to be effective in varying degrees against the original variant of the coronavirus, SARS-CoV-2, that causes COVID-19.

However, since the Delta variant emerged, scientists have been trying to establish whether these vaccines are as effective against it.

You find a breakdown of the current data here, but new research could mean this data will change over time.

The estimated effectiveness of these three vaccines against the Delta variant with two doses (except at single-shot J&J)

Pfizer-BioNTech --- 42 to 96%
J&J --- 67-85%, but More comprehensive studies are needed to reach a definitive answer.
Moderna --- similar protection level as Comirnaty (Pfizer), but a pre-print study suggests around 76%, although this was dismissed by Dr. Anthony Fauci, chief medical adviser to U.S. President Joe Biden and director for the National Institute of Allergy and Infectious Diseases, saying the study, conducted by the Mayo Clinic, was “preprint” and needed to be “fully peer-reviewed” before its findings could be more widely accepted. “I don’t doubt what they’re seeing, but there are a lot of confounding variables in there, about when one was started, the relative amount of people in that cohort who were Delta vs Alpha,” he added.

Another study published in the New England Journal of Medicine (NEJM) found that the effectiveness of two doses of Pfizer-BioNTech’s COVID-19 vaccine was 93.7% among persons with the Alpha variant and 88.0% among those with the Delta variant. With the vaccine of Oxford-AstraZeneca, the effectiveness of two doses was 74.5% among persons with the Alpha variant and 67.0% among those with the Delta variant.

“Only modest differences in vaccine effectiveness were noted with the delta variant as compared with the alpha variant after the receipt of two vaccine doses. Absolute differences in vaccine effectiveness were more marked after the receipt of the first dose. This finding would support efforts to maximize vaccine uptake with two doses among vulnerable populations,” the study concluded.

Five facts about the Delta variant

1. It is more contagious than the other virus strains.

“It’s actually quite dramatic how the growth rate will change,” Dr. Perry Wilson told Yale Medicine last week, commenting on Delta's spread in the U.S. in June. Delta was spreading 50% faster than Alpha, which was 50% more contagious than the original strain of SARS-CoV-2, he says.

“In a completely unmitigated environment—where no one is vaccinated or wearing masks—it’s estimated that the average person infected with the original coronavirus strain will infect 2.5 other people,” Dr. Wilson says. “In the same environment, Delta would spread from one person to maybe 3.5 or 4 other people.”

2. Unvaccinated people are at risk.

Children and young people are a concern as well.

“A recent study from the United Kingdom showed that children and adults under 50 were 2.5 times more likely to become infected with Delta,” said Dr. Inci Yildirim, a Yale Medicine pediatric infectious diseases specialist and a vaccinologist.

3. Delta could lead to 'hyperlocal outbreaks.'

Instead of a three- or four-year pandemic that peters out once enough people are vaccinated, an uptick in cases would be compressed into a shorter period of time. “That sounds almost like a good thing,” Dr. Wilson says. “It’s not.” If too many people are infected at once in a particular area, the local health care system will become overwhelmed, and more people will die, he says. While that might be less likely to happen in the U.S., it will be the case in other parts of the world, he adds. “That’s something we have to worry about a lot.”

4. There is still more to learn about Delta.

Will it make you sicker than the original virus? (A study from Scotland showed the Delta variant was about twice as likely as Alpha to result in hospitalization in unvaccinated individuals, but other data has shown no significant difference.)
How does Delta affect the body? (It seems like cough and loss of smell are less common, while headache, sore throat, runny nose, and fever are present based on the most recent surveys in the U.K., where more than 90% of the cases are due to the Delta strain.)
Could Delta cause more breakthrough cases? (So far, vaccines show high efficacy against Delta.)
Will vaccinated people need booster shots to protect against Delta? (Some experts say its too soon to know whether we will need a booster modified to target the Delta variant—or to bolster protection against the original virus. But both Pfizer and Moderna are working on boosters.)

6. Vaccination is the best protection against Delta.

What can you do?

Face masks can provide additional protection and the WHO has encouraged mask-wearing even among vaccinated people. The CDC updated its guidance in July to recommend that both vaccinated and unvaccinated individuals wear masks in public indoor settings in areas of high transmission to help prevent Delta’s spread and to protect others, especially those who are immuno-compromised, unvaccinated, or at risk for severe disease. The agency is also recommending universal indoor masking for all teachers, staff, students, and visitors to K-12 schools.

“Like everything in life, this is an ongoing risk assessment,” says Dr. Yildirim.

If it is sunny and you’ll be outdoors, you put on sunscreen. If you are in a crowded gathering, potentially with unvaccinated people, you put your mask on and keep social distancing. If you are unvaccinated and eligible for the vaccine, the best thing you can do is to get vaccinated.

The vaccination campaign has been going extremely slowly in Hungary for a while. The 14-day rolling average of new daily shots is 5,418, and the 14-day rolling average of new daily second doses is 6,756.