The Pro Swim Series meeting set for April 16-19 in Mission Viejo, California, was cancelled Monday as USA Swimming extended its moratorium on events because of coronavirus concerns.
The federation sent a letter to members on Monday advising them of the cancelation, and postponement of the Open Water National Championships scheduled for Fort Myers, Florida, April 4-6.
"Throughout the entire country there is a very real and intense effort to stem the spread of the coronavirus (COVID-19)," the emailed memo said. "As responsible leaders, we need to continue to take appropriate steps and ensure that every decision we make is one with a focus on the health and safety of our athletes, members, staff and volunteers."
The Mission Viejo meeting was the penultimate stop in the elite Pro Swim Series.
As of Monday, the Pro Swim event in Indianapolis May 6-9 remained on the schedule. That would be the last pro event before the scheduled June 21-28 Olympic Trials in Omaha, Nebraska.
The federation has now called a halt to all of the camps, conferences and events requiring individuals to travel and gather that it organises through April 30.
"This will continue to be re-evaluated as further information becomes available," USA Swimming said.
The federation has also asked clubs to limit practices and trainings as recommended by their local health authorities.