Illinois State University faculty Assistant Professor of Microbiology Jan-Ulrik Dahl and Associate Professor of Infectious Disease Ecology Benjamin Sadd offer insights on the Omicron variant.

headshot of Dr. Jan-Ulrik Dahl
Dr. Jan-Ulrik Dahl
Man with a backpack with a rock formation in the background
Dr. Ben Sadd

Despite being relatively recent, both SARS-CoV-2 virus and its vaccines are being studied in detail by thousands of scientists and healthcare professionals around the world. New data are gathered, evaluated, and discussed, which is all part of the normal scientific process. Based on these data, responses are adapted accordingly.

As new information becomes available, public health officials want to be able to move quickly to keep communities safe and may change recommendations. With the spread of the highly transmissible Omicron variant, the focus continues to be on prevention.

What is known about the Omicron variant and why is it so transmissible?

  • As of today (January 7, 2022), the Omicron variant is the predominant SARS-CoV-2 strain found in >95% of COVID-19-positive patients in almost every state of the U.S.
  • Early data suggest that Omicron infections result in a significantly higher transmissibility compared to previous variants, which becomes evident with the recent surge in new cases.
  • Because of its extremely high transmissibility, Omicron presents a major threat for unvaccinated and immunocompromised people.
  • Preliminary data suggest that patients with Omicron infections require less intense respiratory support, a shorter length of hospital stay and likely experience an overall reduced disease severity compared to patients infected with previous virus variants, however, Omicron infections should not be dismissed as mild, particularly for those who remain unvaccinated.
  • The current vaccine boosters are very effective against the Omicron variant and protect against severe disease.
  • Researchers predict the variant will continue to spread and new variants will emerge. Preventing infections through vaccination and other recommended practices such as face coverings and proper hand hygiene are key to controlling the pandemic.

Why do new variants such as Omicron represent a major threat?

  • Like every living organism, viruses also undergo evolutionary change, which may enhance their infectivity. SARS-CoV-2 likely also continues to evolve to evade immunity.
  • Omicron carries 34 mutations in the spike protein (required for the attachment to the host cell), which potentially reduce the potency of antibodies raised against previous versions of SARS-CoV-2.

Why do “breakthrough infections” occur in fully vaccinated individuals?

  • It is important to distinguish between COVID-19 infection and disease: the term infection refers to the virus entering and being detectable in our body only, whereas the term disease refers to the virus entering, being detectable in our system AND making us sick.
  • Vaccines can reduce the likelihood of infection, but this has depended on the variant of SARS-CoV-2.
    • In many cases vaccines are not preventatives but act as “flame retardants” during a COVID-19 infection, thus, being infected with COVID-19 is still possible despite being fully vaccinated.
  • However, vaccines have been proven to be very efficient in preventing severe illness or worse.
  • The current vaccines are highly effective: compared to unvaccinated individuals, fully vaccinated individuals who have received an additional booster shot are 10 times better protected from a COVID-19 infection and at 61 times lower risk to die from a COVID-19 infection.
  • Initial studies revealed substantial protection of vaccinated individuals from long-lasting COVID symptoms (also known as long-COVID or post-COVID symptoms). These can occur 4 to 11 months following COVID-19 infections. Specifically, studies revealed a 50-80% reduction in 7 out of the 10 most common symptoms in vaccinated individuals.
  • Breakthrough infections in vaccinated individuals typically cause mild to moderate symptoms and likely shorten the length of illness for infected individuals.

Researchers are continuing to monitor these breakthrough cases and identify patterns or trends in:

    • Patients’ characteristics, such as age or underlying medical conditions,
    • The specific vaccine that patients received,
    • Whether a specific SARS-CoV-2 variant caused the infections.

How can I best protect myself against the Omicron variant?

  • Properly wearing a mask in all indoor settings as well as in crowded outdoor events will further decrease the risk of spreading the virus among students, staff, and faculty.
  • Cloth masks offer protection, but N95/KN95 masks offer better protection in comparison.
    • Illinois State University is procuring a stock of KN95 masks and will make them available to all faculty, staff, and students in the University community. More details related to distribution will be announced soon.
  • Handwashing, distancing, and isolating if you are sick further decreases the risk.
  • Maintaining physical distancing when feasible.

I have not yet received my booster, is it too late?

  • Having received a booster shot in addition to being fully vaccinated with one of the approved vaccines is the most important factor for reducing your risk of becoming infected with SARS-CoV-2.
  • It’s not too late to get vaccinated/boosted! Getting vaccinated is still the most effective way to protect yourself, your children, elderly family members, and your community.

      • Sign-ups for on-campus vaccine booster clinics are now available. Clinics will be operated by the State of Illinois and will be available 8:30 a.m.–4:30 p.m. January 20, 21 and 22 in the Prairie Rooms of the Bone Student Center. While the clinic is focused on boosters, they will also provide first and second doses. These clinics are limited to those who are at least 12 years of age. Minors must be accompanied by a parent or guardian.

How safe are the vaccines for children?

  • While generally milder in children, severe cases of COVID-19 leading to hospitalization and death have been reported. In fact, COVID-19 ranks as one of the top 10 causes of death for children aged 5 through 11 years. Additionally, children may experience short- and long-term complications after COVID-19 infections, including multisystem inflammatory syndrome.
  • The FDA has recently approved the vaccines for emergency use in children ages 5 and older. They have undergone rigorous review of clinical trial data and no serious safety concerns have been identified after vaccination. Side effects, if any, were mild and did not have any lasting effects. Experts continue to carefully evaluate new data to make sure the vaccines are safe and effective for all ages.

Illinois State University continues to gather information and adjust COVID-19 prevention and mitigation strategies based on the newest data and as recommended by the Illinois Board of Higher Education (IBHE), Illinois Department of Public Health (IDPH), and the Centers for Disease Control and Prevention (CDC).

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