A new report from the US Centers for Disease Control and Prevention (CDC) has found COVID-19 was the third leading cause of death in the US in 2021, after heart disease and cancer. Another new CDC report estimates nearly 60 percent of the entire US population had been infected with SARS-CoV-2 by February 2022.
The CDC’s provisional 2021 mortality report found COVID-19 to be the third leading cause of death in the country, for the second year running. The data indicates COVID-19 was the “underlying or contributing cause of death” for 460,513 people last year. This is up from 384,536 COVID-related deaths reported in 2020.
Overall, the report revealed 3,458,697 deaths were recorded in the US in 2021. Heart disease was still the number one cause of death in the country, accounting for 693,021 deaths, with cancer a close second at 604,553 deaths.
A recent pre-print study looking at excess deaths in 2020 and 2021 (those deaths above the expected average numbers) suggests the CDC’s official mortality figures are likely an underestimate of the real impact of COVID-19. That study, yet to be peer-reviewed and published in a journal, suggests more than 170,000 deaths in the country between March 2020 and December 2021 may be COVID-related but not officially reported as such.
Another striking new report from the CDC estimated the real number of COVID-19 cases in the United States is more than double the official case count. The research is what is called a seroprevalence study and it looks for traces of SARS-CoV-2 antibodies in blood samples from large groups of people.
Every month between September 2021 and February 2022 around 70,000 blood samples were tested for the presence of antibodies that signal a current or historic SARS-CoV-2 infection. The findings reveal the true impact of the Omicron wave, showing the overall infection rate in the country jumped from 33.5 percent in December to 57.7 percent in February.
The spike in infections was most pronounced in younger age groups. Seroprevalence spiked in those under the age of 18 from around 45 percent in December to a startling 75 percent in February.
"These findings illustrate a high infection rate for the Omicron variant, especially among children,” the report stated. “Seropositivity for anti-N antibodies should not be interpreted as protection from future infection. Vaccination remains the safest strategy for preventing complications from SARS-CoV-2 infection, including hospitalization among children and adults.”
In a briefing with reporters, Kristie Clarke, from the CDC’s Seroprevalence Task Force, said the data indicates only about one third of all infections have been officially recorded. Clarke also stressed it is still unknown how much immunity is generated from a single infection. Growing numbers of COVID-19 reinfections are being reported so a single infection may not necessarily protect a person from future infection, according to Clarke.
“Having infection-induced antibodies does not necessarily mean you are protected against future infection,” said Clarke. “We still do not know how long infection-induced immunity will last, and we cannot know from the study again whether all the people who tested positive for SARS-CoV-2 antibodies continue to have protection from their prior infection.”
The CDC said its seroprevalence study is designed to pick up SARS-CoV-2 antibodies from infections with any variant over the past two years. So this overall 57.7 percent figure encompasses all Americans infected since the pandemic started in 2020.
The prevalence of COVID-19 reinfections is still a mystery at this point in time. Another recent CDC report discussed 10 reinfection case studies, all occurring within 90 days of a first infection. Some reinfections have led to more severe disease than the first infection.
Source: CDC (Mortality Data, Seroprevalence Study)