The defense contractor built warplanes at the Long Island plant for about six decades, while the Navy had an adjacent, Northrup Grumman-operated facility.
With the official withdrawal from the treaty, which allowed the U.S. and Russia overflight rights to inspect military facilities, only one arms-control pact is still in force between the former Cold War foes.
A study of Marine recruits found that despite these measures and strict quarantines before they started training, the recruits spread the virus to others even though hardly any of them had symptoms.