From Defense Media Network:

“Since 2009, the Department of the Navy has noticed a rise in hazard reports, known as HAZREPS, regarding physiological episodes in the Navy’s F/A-18 and EA-18G fleets,” Turner said.

“We’ve been informed that the Navy has organized a Physiological Episode Team,to investigate and determine the causes of these physiological episodes in aviators.  As symptoms related to depressurization, tissue hypoxia and contaminant intoxication overlap, discerning a root cause is a complex process.