A new study conducted by the U.S. Centers for Disease Control and Prevention (CDC) has found that COVID-19 infection is much deadlier than the flu for hospitalized patients.

The study also found that hospitalized COVID-19 patients were five times more likely to die than hospitalized patients with the flu.

Furthermore, the CDC study found that COVID-19 patients were at greater risk of developing 17 additional, serious medical complications, including pneumonia, acute respiratory distress syndrome (ARDS), and blood clots than flu patients.

However, the study cannot directly compare the mortality rates between the COVID-19 and flu infections because the study was conducted only on hospitalized patients.

Recently, President Donald Trump was criticized for posting on Twitter that COVID-19 infection is “far less lethal” than the flu. He was quickly slammed for spreading misinformation about COVID-19, according to NBC News.

The CDC study was published Tuesday in the CDC journal Morbidity and Mortality Weekly Report (MMWR).

The study researchers compared COVID-19 complications with flu complications using data from Veterans Health Administration hospitals across the nation.

They found that more than 20% of hospitalized COVID-19 patients died compared with only 4% of hospitalized flu patients. They also found that COVID-19 patients were at higher risk of being admitted to the ICU than flu patients.

Furthermore, hospitalized COVID-19 patients were found to be at higher risk of developing dozens of health complications.

When compared with flu patients, COVID-19 patients were roughly 20 times more likely to develop ARDS, a serious lung complication that causes low blood oxygen levels. COVID-19 patients were also found to be at risk of inflammation of the heart muscle (myocarditis), deep vein thrombosis, pulmonary embolism, and intracranial hemorrhage than flu patients.

The researcher wrote, overall, the findings “illustrate the increased risk for complications involving multiple organ systems among patients with COVID-19 compared with those with influenza.”

“Clinicians should be vigilant for symptoms and signs of a spectrum of complications among hospitalized patients with COVID-19 so that interventions can be instituted to improve outcomes and reduce long-term disability,” they added. The article was originally published on Live Science.