The Pentagon is drafting a memo asking military and civilian personnel to report any anomalous health symptoms that may be connected with "Havana Syndrome," a mysterious illness that a number of US diplomats, spies and military personnel have suffered from around the world, according to CNN.
"There's a sufficient amount of concern that with the number of cases that could affect our workforce that this might be a prudent step," a senior defense official said to CNN.
The State Department has already issued a memo on the issue, asking staff to immediately report any symptoms.
In multiple cases, officials reported symptoms alleviating after they changed location.
In one case, a junior White House staffer who had previously suffered from Havana Syndrome later noticed an SUV parked near her house and a man who seemed to be following her. When she stood across from him, she suddenly felt an intense pain in her head and heard a sharp ringing noise which was different than what she experienced in the first case.
Some of the victims experienced lasting symptoms.
The CIA and other government bodies have reportedly been skeptical about the reported illness, with victims' claims being largely dismissed in past cases. That attitude appears to be changing, as a Senate committee reported in April that the number of suspected cases appears to be rising, according to CNN.
On Wednesday, NBC reported that State Department staffers had sent a letter to the State Department leaders demanding that the State Department start taking reports of Havana Syndrome more seriously.
Aaron Reich contributed to this report.