Cases rose threefold in the last several weeks compared to a 25% increase in hospitalization

[GoodTaste]

Cases rose threefold in the last several weeks compared to a 25% increase in hospitalizations due to COVID-19, said David Dowdy, MD, PhD.

Source: WebMD Another COVID Surge is Here, But It May Be Less Severe

Does "rose threefold" here mean "increased 75%" here?

 

[5jj]

I take it to be 300%

 

[emsr2d2]

It means there were three times as many cases.

If the original number of cases was 100, the number at the end of those "several weeks" is 300.
100 x 3 = 300

 

[Skrej]

See -fold suffix definition #1. However, you're multiplying by whatever the number of cases was several weeks prior (which isn't stated), not the 25% hospitalization increase.

The total number of cases increased threefold, not the hospitalization rate. Hospitalizations rose only 25% over the same period. That's the evidence to support that the latest surge isn't as severe.