Four prescription drug providers told Warren and Casey that delivery times this summer have increased by half a day or more, on average, compared with earlier this year or similar time frames in 2019, according to the Senate report, which was shared early with The Washington Post. Deliveries that might typically take two or three days were instead taking three to four, the lawmakers said, and one pharmacy in particular saw a “marked increase” in the number of shipping delays at or exceeding seven days.

“These delays are unacceptable outcomes under any circumstances, but are made even worse by the ongoing pandemic, which has increased demand for mail-order drugs as many Americans are affected by stay-at-home orders or choose to stay at home in order to remain safe,” the senators wrote in a letter to the Postal Service’s Board of Governors.

The medicine delays, in some cases, appear to have started around May, when DeJoy had been tapped for the job but before he officially took the reins. The timeline raises the possibility that the coronavirus outbreak may have contributed to slowdowns for mailed prescription drugs, particularly as patients put new strain on the system by shifting away from in-person pick-up to delivery.