Data Indicate Omicron is Milder, Better at Evading Vaccines

December 14, 2021by Andrew Meldrum, Associated Press
Data Indicate Omicron is Milder, Better at Evading Vaccines
A man gets vaccinated against COVID-19 at a site near Johannesburg, Monday, Dec. 13, 2021, a day after South African President Cyril Ramaphosa tested positive for COVID-19. (AP Photo/Denis Farrell)

JOHANNESBURG (AP) — The omicron variant appears to cause less severe disease than previous versions of the coronavirus, and the Pfizer vaccine seems to offer less defense against infection from it but still good protection from hospitalization, according to an analysis of data from South Africa, where the new variant is driving a surge in infections.

While the findings released Tuesday are preliminary and have not been peer-reviewed — the gold standard in scientific research — they line up with other early data about omicron’s behavior, including that it seems to be more easily transmitted.

A two-dose Pfizer/BioNTech vaccination appeared to provide just 33% protection against infection during South Africa’s current omicron wave, but 70% protection against hospitalization, according to the analysis conducted by Discovery Health, South Africa’s largest private health insurer, and the South African Medical Research Council.

The data were gathered from Nov. 15 to Dec. 7, during which time omicron was first spotted by scientists in South Africa and Botswana, and may change as time passes. Experts now say that omicron accounts for more than 90% of all new infections in South Africa, according to Discovery Health chief executive Dr. Ryan Noach.

Researchers around the world are rushing to figure out what omicron will mean for the coronavirus pandemic now well into its second year. More information came Tuesday from Pfizer, which announced that its experimental pill to treat COVID-19 — separate from it its vaccine — appears effective against the new variant.

The company also said full results of its 2,250-person study confirmed the pill’s promising early results against the virus: The drug reduced combined hospitalizations and deaths by about 89% among high-risk adults when taken shortly after initial virus symptoms. Separate laboratory testing shows the drug retains its potency against the omicron variant.

In the weeks since omicron was detected, South Africa has experienced rapid spread of the virus — concentrated in its most populous province, Gauteng. The seven-day rolling average of daily new cases in the country rose over the past two weeks from 8.07 new cases per 100,000 people on Nov. 29 to 34.37 new cases per 100,000 people on Dec. 13, according to Johns Hopkins University. The death rate hasn’t increased during that same period.

“The omicron-driven fourth wave has a significantly steeper trajectory of new infections relative to prior waves. National data show an exponential increase in both new infections and test positivity rates during the first three weeks of this wave, indicating a highly transmissible variant with rapid community spread of infection,” Noach said.

Although case numbers are rising, hospitalizations are not increasing at the same rate, leading the scientists to report that the risk of hospitalization from omicron is lower than delta or earlier variants. Hospital admissions for adults diagnosed with COVID-19 are 29% lower compared to the wave that South Africa experienced in mid-2020, after adjusting for vaccination status, according to the analysis.

The result shows that people who received two doses of the Pfizer vaccine had 33% protection against infection in the first weeks of South Africa’s current omicron-driven wave. That’s a significant drop from the 80% protection against infection afforded during earlier periods.

The researchers say it’s encouraging that the study shows that people fully vaccinated with Pfizer have 70% protection against hospital admission during the omicron surge. That’s still a drop from the 93% protection seen in South Africa’s delta-driven wave.

The study shows that significant protection against hospital admission even among older age groups, with 67% in people aged 60 to 69 and 60% for people aged 70 to 79.

The analysis was based on examining more than 211,000 positive COVID-19 test results, 41% of which were for adults who had received two doses of the Pfizer vaccine. About 78,000 of the positive results were attributed to omicron infections.

The South African analysis supports an earlier assessment by U.K. authorities.

The U.K. Health Security Agency said Friday that new data from the U.K. confirm that omicron is more easily transmissible than other variants. Other studies suggest that both the AstraZeneca and Pfizer vaccines are less effective in preventing symptomatic infections in people exposed to omicron, though preliminary data show that effectiveness appears to rise to between 70% and 75% after a third booster dose.

The study also found that omicron poses a higher risk of reinfection. For individuals who have previously had COVID-19, the risk of reinfection with omicron is significantly higher than that of earlier variants.

A+
a-
  • omicron
  • Pfizer
  • South Africa
  • vaccine
  • In The News

    Health

    Voting

    COVID-19

    February 13, 2024
    by Dan McCue
    CDC Said to Be Poised to Revise COVID-19 Isolation Recommendation

    ATLANTA — The Centers for Disease Control and Prevention is ready to toss its recommendation that individuals isolate themselves for... Read More

    ATLANTA — The Centers for Disease Control and Prevention is ready to toss its recommendation that individuals isolate themselves for five days following a positive test for the coronavirus. The pending change, which appears slated for an April announcement, was first reported by The Washington Post.... Read More

    Holiday Gatherings and a New Variant Have Driven Up COVID Cases Globally, the UN Health Agency Says

    GENEVA (AP) — The head of the U.N. health agency said Wednesday holiday gatherings and the spread of the most... Read More

    GENEVA (AP) — The head of the U.N. health agency said Wednesday holiday gatherings and the spread of the most prominent variant globally led to increased transmission of COVID-19 last month. Tedros Adhanom Ghebreyesus said nearly 10,000 deaths were reported in December, while hospital admissions during... Read More

    As Pandemic Unfolded, Deaths of Older Adults in Pennsylvania Rose Steeply in Abuse or Neglect Cases

    HARRISBURG, Pa. (AP) — Pennsylvania recorded a steep increase in the deaths of older adults following an abuse or neglect... Read More

    HARRISBURG, Pa. (AP) — Pennsylvania recorded a steep increase in the deaths of older adults following an abuse or neglect complaint the last few years, as COVID-19 ravaged the nation, complaints grew and agencies struggled to keep caseworkers on staff. The staggering increase shown in state... Read More

    States Trashing Troves of Masks and Pandemic Gear as Costly Stockpiles Linger and Expire

    When the coronavirus pandemic took hold in an unprepared U.S., many states like Ohio scrambled for masks and other protective... Read More

    When the coronavirus pandemic took hold in an unprepared U.S., many states like Ohio scrambled for masks and other protective gear. Supplies were so limited in 2020 that the state bought millions of medical gowns from a marketing and printing company and spent about $20 million to try... Read More

    Anthony Fauci to Testify Before Congress on COVID Origins and US Pandemic Response

    WASHINGTON (AP) — Anthony Fauci, former chief White House medical adviser, is expected to testify before Congress early next year... Read More

    WASHINGTON (AP) — Anthony Fauci, former chief White House medical adviser, is expected to testify before Congress early next year as part of Republicans' yearslong investigation into the origins of COVID-19 and the U.S. response to the disease. Fauci, who served as the nation's top infectious... Read More

    FDA Advisers Consider Changing COVID Vaccine to Target Latest Omicron Strain

    The COVID-19 vaccines are on track for a big recipe change this fall. Today’s vaccines still contain the original coronavirus... Read More

    The COVID-19 vaccines are on track for a big recipe change this fall. Today’s vaccines still contain the original coronavirus strain, the one that started the pandemic — even though that was long ago supplanted by mutated versions as the virus rapidly evolves. Thursday, the Food... Read More

    News From The Well
    scroll top