You should explore the data yourself and draw your own conclusions. The numbers presented in that article don't seem abnormal when you look at the broader data set. For example, the change in heart disease deaths week-to-week for those same dates but in the previous year (2019)...
4-13 -923
4-20 +318
4-27 -736
There are weeks in 2019 when the numbers jump up or down by 1200 or more. Which is probably why the author of that article chose to cherry pick 3 weeks in the table of cause of death fluctuations.
You should explore the data yourself and draw your own conclusions. The numbers presented in that article don't seem abnormal when you look at the broader data set. For example, the change in heart disease deaths week-to-week for those same dates but in the previous year (2019)...
4-13 -923
4-20 +318
4-27 -736
There are weeks in 2019 when the numbers jump up or down by 1200 or more. Which is probably why the author of that article chose to cherry pick 3 weeks in the table of cause of death fluctuations.