A 2nd Navy sailor on a US warship has tested positive for the coronavirus - this time aboard a destroyer

U.S. Navy photo by Mass Communication Specialist 3rd Class Anthony Collier

A sailor stands port-lookout aboard the guided-missile destroyer USS Ralph Johnson.

• The coronavirus has spread to another US Navy sailor aboard a warship, this time a guided-missile destroyer.
• Following the announcement that a sailor aboard the amphibious assault ship USS Boxer had tested presumptive positive, the Navy said Tuesday that a sailor aboard the USS Ralph Johnson also had been infected.
• Protecting Navy warships, tight spaces filled with military personnel, from the coronavirus poses a daunting challenge for the service.
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The coronavirus that causes the illness COVID-19 and first appeared in China but has since become a global pandemic has infected another US Navy sailor aboard a warship - this time a destroyer, the Navy said Tuesday.

A sailor assigned to the USS Ralph Johnson, a guided-missile destroyer at port in Everett, Washington, tested positive for the virus Monday, according to the Navy.

The destroyer is undergoing an extensive cleaning to prevent further spread, and the sailor is isolated at home.

The first US Navy sailor to test positive for the virus is assigned to the amphibious assault ship USS Boxer but is currently quarantined at home in San Diego, as are individuals identified as having had close contact with the sailor. Military health professionals are investigating whether or not others were exposed.

Both California and Washington have hundreds of coronavirus cases and have experienced dozens of related deaths.

The coronavirus has spread to nearly 6,000 people and killed almost 100 in the US. The number of US military personnel who have tested positive is lower, with the total presently around 20, but the virus continues to spread.

For the Navy, its warships are a serious concern.

Last year, the USS Fort McHenry, a Whidbey Island-class dock landing ship carrying both sailors and Marines, experienced an unusual viral outbreak. Mumps hit the ship hard, infecting 28 people despite efforts to quarantine the infected and disinfect the vessel.

That was a vaccine-preventable illness. There is no vaccine for the coronavirus, which has infected to nearly 200,000 people and killed 7,800 worldwide. Sailors live in close proximity aboard Navy ships, and communicable diseases are easily transmittable.

Navy ships are filled with personnel and are not exactly conducive to social distancing. The Boxer, for instance, can carry up to 1,200 sailors and 1,000 Marines.

Pacific Fleet is begging sailors to stay off ships if they feel unwell.

"We don't want sick sailors on our ships right now," Cmdr. Ron Flanders, Naval Air Forces spokesman, told The San Diego Union-Tribune on Monday. "If sailors are feeling ill, they should notify their chain of command."

Some questions have been raised about the Navy's response to infections aboard warships.

Shortly after the revelation that a sailor aboard the Boxer had tested "presumptive positive" for the virus, military leaders gathered around 80 crew members into a small room for a half-hour meeting to discuss the importance of social distancing and other preventative practices, ProPublica reported Monday.

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