NIH STUDY: 3 interventions had the most impact on COVID infections: closing schools, closing bars, wearing masks.
Here's Maryland where trajectory of case rate (green) hospitalizations (blue) and death (black) all change with a few days of lag time after closures
1/n
Here's Maryland where trajectory of case rate (green) hospitalizations (blue) and death (black) all change with a few days of lag time after closures

Researchers also looked at school closure, alone. Here's Georgia where school closure occurred prior to closing bars and appears to cut the rate of infections (green) in half, beginning 8-14 days post-closure. Rates of hospitalizations (blue) & death (black) also went down (2/n)
Mask mandates also led to a drop in the rate of infections (green); drops in the rates of hospitalizations (blue); and deaths (black) "Mandating masks is to drop the slopes about 2 fold". Here's New Jersey (3/n)
They found that post-opening surges seemed to be strongly correlate w/opening bars. Conversely, data suggests the simple combination of closing bars and wearing masks (see Red Arrows) was an effective way to clamp down rates. Here's Arizona (4/n)
Overall, school closings dropped infection rates in half; lockdowns dropped rates 3 to 4 fold; other actions (such as closing bars & mandating masks) brought the rates further down. Hospitalizations and deaths lagged, but paralleled cases. Preprint: (5/n) https://www.medrxiv.org/content/10.1101/2020.09.26.20202457v1