The American Israel Public Affairs Committee warned Congress, the Trump administration and activists among others that at least two people who attended the lobby’s policy conference have tested positive for the coronavirus.

The conference, which ran from Feb. 28-March 2, drew 18,000 activists to Washington.

On Twitter, AIPAC said an email was going out to all attendees as well as to congressional and administration offices. The conference routinely attracts Congress members and their staffers, as well as top administration officials, in the most recent case, Vice President Mike Pence and Secretary of State Mike Pompeo. Additionally, on the last day of the conference, activists visit virtually every congressional office to lobby.

The AIPAC statement posted late Friday on Twitter said the two people who tested positive are from New York. The outbreak has been especially hard on the Orthodox Jewish community in Westchester County, and AIPAC listed the county’s health department as among the authorities with which it is in communication.

The others are the New York Health Department, national health authorities and the District of Columbia Health Department. The statement also said the lobby was consulting with Edward Septimus, a professor of internal medicine at Texas A&M University.

Important Update: Coronavirus

As emailed to Policy Conference attendees, participants, speakers, administration and Hill offices.https://t.co/0mkWeuRErA pic.twitter.com/EHl694pkgJ

— AIPAC (@AIPAC) March 6, 2020