Unvaccinated people at higher risk of needing ICU for Omicron

Vaccinated adults with COVID-19 had less severe illness during the omicron surge, compared with unvaccinated adults ­– who were more likely to need intensive care

The Omicron variant of the SARS-CoV-2 virus has become the dominant strain across numerous countries. It is highly contagious and has spiked hospitalisations for those with COVID-19, since December 2021.

According to a new study by Cedars-Sinai and the Centers for Disease Control and Prevention (CDC), patients who are vaccinated have a better time surviving the Omicron variant, whereas those who are unvaccinated frequently require intensive care for more serious conditions.

The research indicates the serious need for adults at risk of the virus to get vaccinated, to better protect themselves and others against any strain of COVID-19.

Invasive mechanical ventilation is the only option

Taken from from July to September of 2021, researchers took data from a single-hospital study analysing 339 patients hospitalized with COVID-19 in Los Angeles during the surge of the Delta variant.

They then took that data and compared it with a group with 737 patients admitted with COVID-19 during December 2021 to January 2022, when the Omicron variant was most prevalent.

Taking information of the patients from their electronic health records, the study and then evaluated by a team of investigators, revealing that a greater portion of the patients hospitalised during omicron were vaccinated as compared to patients hospitalized during the summer of 2021 when the Delta variant predominated, likely reflecting the higher percentage of the populations that were vaccinated during Omicron.

Researchers found that during the Omicron period fewer patients died while hospitalised (4.0%), compared with those admitted when the Delta variant was dominant (8.3%), showing that although the Omicron variant is more contagious, the death rate luckily is lower.

However, this again demonstrates the success of the vaccinations, as more people were vaccinated during Omicron’s surge.

Matthew Modes, MD, a pulmonologist at Cedars-Sinai and co-first author of the paper, said: “Overall, the omicron-period group had a lower likelihood of being admitted to the intensive care unit (ICU) and were also less likely to require invasive mechanical ventilation compared with the delta-period group.

Peter Chen, MD, senior author of the study and director of Pulmonary and Critical Care Medicine at Cedars-Sinai, added: “In addition to the protection that vaccination offered people admitted to the hospital when omicron dominated, we saw that the addition of a booster dose appeared to be particularly important in reducing the severity of illness, especially among older adults.”

Unvaccinated patients also at higher risk of respiratory failure

Chen continued: “Unvaccinated patients hospitalised with COVID-19 during the Omicron variant dominance still had a higher chance of being admitted with serious complications and appeared to be at higher risk for the development of respiratory failure, compared with vaccinated patients.”

The large number of patients in hospitals during the entirety of the pandemic has put extreme strain on health systems throughout the country, and the world.

Vaccination, including a booster dose for those who are fully vaccinated, remains critical for mitigating the risk of severe illness associated with SARS-CoV-2 infection.

Due to the severity of the COVID-19 pandemic, many people with diseases who require intensive care for conditions such as cancer, or organ failure, do not receive the vital treatment necessary because most hospital resources and workers are focused on treating those with COVID-19.

Therefore, vaccinations are essential to bringing down the hospitalisation rate, so hospitals can again treat other conditions in need too.

Michael Melgar, MD, a co-first author of the study and a medical officer with the CDC, finalised: “A clear pattern emerges if you take just the omicron-period patients and compare their vaccination status against the percentage of them who ended up in the ICU.

“The more vaccinated someone is–from unvaccinated, partially vaccinated, fully vaccinated without a booster dose to fully vaccinated with a booster dose−the better the outcome for the patient.”