Flu A is generally considered more severe than Flu B due to its greater potential for intense symptoms and complications, though both can be serious depending on individual health factors.

Symptom Comparison

Flu A often hits harder with rapid-onset high fevers, severe body aches, persistent coughs, and stronger upper respiratory issues that escalate quickly. In contrast, Flu B symptoms tend to develop more gradually and feel milder overall, with less intense fevers and aches, though young children may still face tough bouts. Gastrointestinal upset is rarer in both but can appear mildly in Flu A among vulnerable groups.

Severity in Studies

A CDC analysis of over 24,000 hospitalized adults across eight seasons found no major differences in ICU admissions, hospital stays, or death rates between Flu A and B infections. However, Flu A subtypes like H3N2 have historically driven more hospitalizations and fatalities, especially in kids and seniors. Recent insights echo that Flu A poses broader risks for pneumonia or bronchitis in older adults and immunocompromised people.

Who’s at Risk?

  • High-risk for Flu A : Older adults, pregnant individuals, and those with weak immunity often suffer worse outcomes and complications.
  • High-risk for Flu B : Children under 5 and sometimes seniors, where it can mimic Flu A severity despite milder averages.

Both types demand the same antiviral treatment approach—don’t downplay Flu B clinically.

Prevention Tips

Annual flu shots cover major strains of both A and B, offering the best defense amid shifting seasonal dominance. Handwashing, masking in crowds, and staying home when sick curb spread—Flu A’s wider animal reservoir makes it trickier to predict.

TL;DR : Flu A edges out as "worse" for most due to severity and reach, but Flu B isn’t a lightweight—vaccinate regardless.

Information gathered from public forums or data available on the internet and portrayed here.