The FDA’s device center has resumed a more normal pace of warning letter issuance in recent months, and the latest batch posted to the warning letter website features warning letters to one device maker in Europe and three firms in Asia. One U.S. firm, Steiner Biotechnology LLC, of Henderson, Nev., also received a warning, however, which is the second the company has received since June 2017.

FDA warning letters to device makers have been conspicuous in their paucity in recent years, but they have been surfacing with greater frequency over the past few months.

The FDA's Center for Drug Evaluation and Research (CDER) issued 62% more warning letters under the first part of the Trump administration than it did during the last few years of the Obama administration. But the number of warnings for medical devices, food and tobacco products fell sharply under President Donald Trump, according to an investigative report being published in the July 5 issue of Science.

In the words of former FDA Commissioner Scott Gottlieb, the five-week government shutdown that ended Jan. 25 was "the most difficult operational challenge we have faced in modern times." While the full impact of that challenge could ripple through the FDA for a while, it made little difference in the number of warning letters the agency sent out between Dec. 23 and Jan. 25.