COVID-19 in its current form is significantly less deadly than it was during the first two years of the pandemic, but it remains a serious illness that causes more harm than most people realize. For hospitalized patients, outcomes now look similar to severe influenza in most age groups, with one notable exception: adults aged 18 to 49 still die from COVID at higher rates than from the flu. Beyond the acute infection, the virus carries risks to the heart, brain, and lungs that accumulate with repeated infections.
How Severe Is a Typical Case Now?
Most people who catch COVID today experience a few days of fever, body aches, sore throat, and fatigue that resolve within a week or two. The shift from earlier pandemic waves is dramatic. CDC data comparing hospitalized patients with Omicron-era COVID to those with seasonal flu found similar rates of ICU admission, supplemental oxygen use, and mechanical ventilation between the two diseases. For adults over 50, the in-hospital death rate was statistically indistinguishable from influenza.
That said, roughly 91% of people hospitalized with COVID had at least one underlying condition that raised their risk, such as obesity, diabetes, heart disease, or a weakened immune system. If you’re otherwise healthy and have some immune history from vaccination or prior infection, your odds of a mild illness are high. But “similar to the flu” still means tens of thousands of hospitalizations each year and a real risk of complications for vulnerable people.
The Virus Doesn’t Just Attack Your Lungs
One reason COVID is more dangerous than a typical respiratory virus is what it does beyond the airways. The virus targets cells lining blood vessels throughout the body. Research published through the American Heart Association showed that even the spike protein alone can damage these cells, impairing their ability to produce nitric oxide, a molecule that keeps blood vessels relaxed and healthy. This disruption triggers oxidative stress and shifts how cells generate energy, essentially forcing them into a less efficient metabolic state.
This vascular damage helps explain why COVID can cause heart inflammation, blood clots, kidney injury, and neurological symptoms in people who never had severe respiratory illness. Hospitalized COVID patients were more likely than flu patients to need medication to support blood pressure and to require treatment for kidney failure, even during the milder Omicron era. The virus is a respiratory infection that behaves like a vascular disease.
Repeated Infections Compound the Risk
One of the most important findings since the pandemic began is that each COVID infection adds risk rather than building tolerance. A large study from Washington University tracking health outcomes found that people reinfected with COVID were 3.5 times more likely to develop lung problems, 3 times more likely to develop heart conditions, and 1.6 times more likely to experience brain-related complications compared to those infected only once. Repeat infections also increased the risk of hospitalization and death.
This is a meaningful departure from how many people think about the virus. Getting it once doesn’t make the next round harmless. The cumulative damage to blood vessels, organs, and the immune system appears to build over time, which makes prevention still relevant even for people who have already recovered from one or more infections.
Long COVID Remains Common
As of 2023, about 6.4% of U.S. adults reported experiencing long COVID at the time they were surveyed. That’s defined as symptoms lasting three months or longer that weren’t present before infection. Common complaints include persistent fatigue, brain fog, shortness of breath, and exercise intolerance.
The economic toll has been substantial. Across OECD countries, long COVID reduced the labor force by nearly 1% in 2021. In the U.S., a study tracking over 150 million workers through 2024 found a 12.9% increase in health-related work absences and a 13.1% rise in people leaving the workforce entirely, compared to pre-pandemic levels. Among people with severe long COVID, roughly 18% exit the labor force completely. This isn’t just a medical problem. It reshapes careers, household income, and the broader economy.
How COVID Affects Children
Children generally handle COVID well, with most experiencing mild or even asymptomatic infections. The most serious pediatric complication, Multisystem Inflammatory Syndrome in Children (MIS-C), has declined by 98% from its peak in late 2020 and early 2021. In 2023, the incidence dropped to 0.11 cases per million person-months.
MIS-C remains serious when it occurs. Among the 117 cases identified in 2023, half required intensive care, about a third experienced shock, and over a quarter had cardiac dysfunction. The typical hospital stay was four days. But the steep decline in cases, likely driven by widespread immunity in the pediatric population, means this is now a rare event rather than a common concern.
How Well Does Immunity Hold Up?
If you’ve been both vaccinated and previously infected, you have what researchers call hybrid immunity, and it provides strong, durable protection against the worst outcomes. A systematic review published in The Lancet Infectious Diseases found that hybrid immunity still prevented hospitalization or severe disease about 97% of the time at 12 months after the last vaccination or infection.
Protection against catching the virus again fades within months, which is why reinfections are common. But protection against ending up in the hospital stays high for much longer. For people with hybrid immunity, researchers suggested that waiting six months between booster doses and the last infection or vaccination is reasonable, since the shield against severe illness holds well over that window.
Treatment Options for High-Risk Cases
Antiviral treatment taken within five days of symptom onset cuts hospitalization rates roughly in half for adults diagnosed with COVID. That benefit held across age groups and even among people who had already received three vaccine doses. The greatest reduction in hospitalization was among adults aged 50 to 64, with a 60% lower rate compared to those who didn’t receive treatment.
Antivirals are most valuable for people at higher risk: older adults, those with chronic conditions, and immunocompromised individuals. For a healthy 30-year-old with mild symptoms, the benefit is smaller because the baseline risk of hospitalization is already low. If you test positive and have risk factors, starting treatment early makes a measurable difference in outcomes.
The Bottom Line on Severity
COVID in 2024 and beyond is not the crisis it was in 2020, but calling it “just a cold” understates the reality. It still hospitalizes and kills people at rates comparable to a bad flu season, causes lasting symptoms in roughly 1 in 16 adults who catch it, and inflicts cumulative damage with each reinfection. For most healthy, vaccinated people, any single infection will likely be manageable. The broader concern is what happens over years of periodic reinfections, particularly to the heart and brain, where the evidence points to risks that add up quietly over time.