A flurry of scientific gatherings and panels across federal science agencies were canceled on Wednesday, at a time of heightened sensitivity about how the Trump administration will shift the agencies’ policies and day-to-day affairs.

Several meetings of National Institutes of Health study sections, which review applications for fellowships and grants, were canceled without being rescheduled, according to agency notices reviewed by STAT. A Feb. 20-21 meeting of the National Vaccine Advisory Committee, a panel that advises the leadership of the Department of Health and Human Services on vaccine policy, was also canceled. So was a meeting of the Presidential Advisory Council for Combating Antibiotic-Resistant Bacteria that was scheduled for Jan. 28 and 29.

The scope of the cancellations was unclear. It was also unclear whether they were related to the Trump administration’s freeze on external communications until Feb. 1.

“Peer review via study sections is required by law in order for the NIH to disburse most of the $40 billion annual extramural budget,” said Norman E. Sharpless, a former director of the National Cancer Institute, part of the NIH. “If study sections and advisory council meetings are postponed for more than even a brief period, this will likely lead to interruptions in grant funding, which is bad for U.S. biomedical research.”