News|Articles|May 29, 2024

Mortality Rate During Pre-Vaccination Period was 44% for COVID-19 ICU Inpatients

Deaths varied greatly depending on the age group, with the oldest population having the highest rates.

Nearly half of all Americans who were hospitalized for COVID-19 and placed in the intensive care unit died in the period of time (May 1–December 1, 2020), prior to the authorization of vaccines.

This data comes from a study published in the Centers for Disease Control and Prevention’s (CDC) Emerging Infectious Diseases journal.

Specifically, the investigators found that 18% of overall hospitalized patients, and 44.2% of those admitted to the ICU died.

“This analysis presents case-hospitalization and case-fatality rates by age group, sex, and racial and ethnic groups before the introduction of vaccinations targeting SARS-CoV-2,” the investigators wrote.

Study Parameters and Results
Data was collected from 56 United States jurisdictions from information collected by state and territorial epidemiologists who submitted COVID-19 case reports to the CDC using a standard COVID-19 form during the aforementioned time period.

This investigators estimated rates in large populations that included 2.4 million COVID-19 cases for measuring hospitalization rates and 4.7 million cases for fatality rates.

As can be seen by the numbers in the table listed below, variables such as age was the biggest risk factor for mortality. Specifically, those who were 85 years of age and older were at 23.6% mortality rate and conversely those who were ages 1-14 years of age, had a .05% mortality rate.


Although males (1.9%) had a similar mortality rate as females (1.5%), males did have a higher hospitalization rate—Male: 6.2% vs Female: 5.2%—which then leads to more male mortality. The exception was in the 15–24- and 25–34-year age groups in terms of hospitalization rates.

In terms of race, the Black not Hispanic population had the highest hospitalization rate with 14.0% adjusted; this was followed by the Asian or Pacific Islander, not Hispanic population who were at 11.2% adjusted; and then the White, not Hispanic: 6.8% adjusted. The mortality rates were highest for the Asian or Pacific Islander, not Hispanic population at 3.0% (4.4% adjusted); followed by the Black, not Hispanic: 2.8% (4.0% adjusted); and then White, not Hispanic: 2.7% (1.5% adjusted).

Takeaways
Although the investigators did not look forward with data regarding to mortality during a post-vaccination period, they did communicate the importance of vaccination for reduction efforts.

“The introduction of vaccinations and the presence of new strains of SARS-CoV-2 altered those rates," the investigators wrote.

"Our results document the severity of SARS-CoV-2 infections early in the pandemic, provide a baseline for future comparisons, and highlight the importance of preventing severe illness in high-risk populations (e.g., through vaccination, early identification of symptoms, testing, and isolation to prevent transmission)."
 



Reference
Griffin I, King J, Lyons B, et al. Estimates of SARS-CoV-2 Hospitalization and Fatality Rates in the Prevaccination Period, United States. Emerging Infectious Diseases. 2024;30(6):1144-1153. doi:10.3201/eid3006.231285.





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