Flu's link to cardiovascular disease shows why vaccination is essential

"When most people think of influenza, they imagine a few days of fever, body aches and bed rest. Flu is often regarded as a threat to the very old, the very young or those with compromised immune systems. The rest of us are reassured we'll recover quickly. After all, 'it's just the flu'. Seasonal influenza doesn't appear in the top ten causes of death in the United States. During the 2023-24 flu season, there were an estimated 28,000 flu-related deaths."

"And the collective failure of the health community to understand that relationship has serious implications for patients, their families and the health systems that care for them. The evidence is compelling. A study in 2018 found that the risk of a heart attack jumps sixfold in the week after a confirmed flu infection. Another study, involving more than 80,000 adults hospitalized with influenza, found that nearly one in eight experienced an acute cardiovascular event."

"The connection between influenza and a host of cardiovascular conditions is not a surprise. Scientists have long known that the virus affects more than the respiratory tract. It triggers a powerful inflammatory response, sending the immune system into overdrive. This response can activate blood platelets, increasing the risk of blood-clot formation. Fever elevates heart rate and energy demands, and dehydration adds further strain. The result is a physiological storm that can tip vulnerable people - especially those with underlying cardiovascular disease - into crisis."

Seasonal influenza causes relatively fewer direct deaths but substantially raises risk of acute cardiovascular events and can precipitate heart attacks. Epidemiological studies found a sixfold increase in heart attack risk in the week after confirmed influenza and nearly one in eight hospitalized influenza patients experienced an acute cardiovascular event. Influenza triggers systemic inflammation, activates platelets and increases fever, heart rate and dehydration, producing physiological stress that can tip people with underlying cardiovascular disease into crisis. These interactions link infectious and chronic disease burdens and justify prioritizing influenza prevention and clinical vigilance for cardiovascular complications.

Read at Nature