The COVID-19 pandemic spread to many military ships. The nature of these ships, which includes working with others in small enclosed areas and a lack of private quarters for the vast majority of crew, contributed to the rapid spread of the disease, even more so than on cruise ships.

Due to the nature of operations security, national militaries may have policies in place that prevent or restrict reporting of SARS-CoV-2 infections and COVID-19 deaths, so although the cases listed below may have been widely reported in reliable sources, confirmation by official spokespeople of the respective militaries is not systematic.

Summary of confirmed cases + Military ship incidents with confirmed positive cases § Ship Crew Tests Cases Dead Docking date Docking location Dock Country § 2 none Naval Base San Diego US § ≥3 § 1 none Naval Station Everett USA § ~60 9 none Naval Base San Diego USA § 1 none Puget Sound Naval Shipyard USA § USS Theodore Roosevelt 5000 5000 1156 1 27 March 2020 Guam USA § 1 27 March 2020 Zeebrugge Belgium § 16 none Yokosuka Naval Base Japan § HNLMS Dolfijn 58 15 8 3 April 2020 Den Helder Netherlands § 2 none Pier 90 USA § 2 none Puget Sound Naval Shipyard USA § 7 none Port of Los Angeles USA § Charles de Gaulle 1760200 ≥2010 1046≥35 12 April 2020 Arsenal de Toulon France § ≥630 ~24 none Pascagoula USA § ROCS Pan Shi 337 337 31 15 April 2020 Zuoying Naval Base Taiwan § ~330 ~330 ≥96 28 April 2020 Naval Base San Diego USA § ~50 52 2 none Boston USA § ~400 100% ≥2 none JEBLCFS USA § 65 3 15 June 2020 Port of Subic Bay Philippines § 5 none Naval Base San Diego USA § ≥1 none Norfolk Naval Shipyard USA

Belgium

Leopold I

On 25 March, Belgian Defense reported that a crew member of the Belgian frigate had tested positive. The sailor had been evacuated via air to Den Helder on 20 March after he began showing symptoms, and was quarantined at home when the test returned positive on 24 March. As a precaution, the ship broke off from its operation with the French carrier battle group led by Charles de Gaulle and returned to Zeebrugge, its home port, on 27 March, about a month earlier than planned.

France

Carrier battle group of Charles de Gaulle

Because about 40 crew members were beginning to show symptoms, the French aircraft carrier returned to its home port in Toulon earlier than planned, as reported on 8 April 2020 by the Ministry of Armed Forces. Other ships that were part of the carrier battle group also began to return to their home ports.

After 66 sailors aboard Charles de Gaulle were tested, the ministry announced on 10 April that 50 tests had returned positive. Three sailors were evacuated by air to .

The carrier had been on a months-long mission leading a carrier battle group when its first coronavirus case was reported. Another ship participating in the mission, Belgium's Leopold I, had broken off to return to port weeks earlier due to a case of coronavirus being found on board.

On 12 April 2020, the Marine Nationale reported that Charles de Gaulle and accompanying air-defense frigate had returned to Toulon, while command and replenishment tanker and anti-submarine frigate had returned to Brest. The 1,700 sailors of Charles de Gaulle and 200 sailors of Chevalier Paul were subsequently quarantined for two weeks.

On 15 April, the Ministry of Armed Forces reported that, out of the 1,767 tests that had been conducted on the members of the carrier battle group so far, 668 had returned positive. The vast majority of these cases were aboard Charles de Gaulle, and the remainder of the cases were reported to be aboard Chevalier Paul.

On 17 April, , Central Director of the Military Health Service, reported to the that all 2,300 sailors of the carrier battle group had been tested upon their return to Toulon, and so far, 940 had tested positive while 645 had tested negative. On the same day, Florence Parly, Minister of the Armed Forces, reported to the National Assembly's that 2,010 sailors of the carrier battle group had been tested, with 1,081 tests returning positive so far. The Navy clarified that, on Charles de Gaulle itself, the final number was 1,046 positive cases out of 1,760 tested.

In total, 545 sailors had shown symptoms and 24 had been hospitalized at the Saint Anne Army Teaching Hospital, including 2 admitted to the ICU.

On 29 April 2020, the Navy stated that 19 sailors aboard Chevalier Paul had tested positive upon arrival at Toulon.

On 11 May 2020, Florence Parly reported to the National Assembly the conclusions of two investigations into the outbreak on board the carrier, stating that the virus had first arrived before a stopover made in Brest, and that although the command and medical team aboard the carrier had "excessive confidence" in their ability to deal with the virus, the investigations did not consider them at fault.

Parly further explained that the introduction of the virus on board the carrier happened sometime between when it left Limassol, Cyprus, on 26 February 2020, and when it arrived at Brest on 13 March 2020. During this time, personnel had been brought on board via air from either Cyprus, Sicily, the Balearic Islands, Spain, or Portugal. The spread of the virus, however, was exacerbated by the stopover at Brest. Social distancing and other measures were taken after the stopover, but they weighed heavily on crew morale, so after enforcing the strict measures for a fortnight, they were relaxed, and a concert on board was authorized for 30 March.

Parly also noted that all soldiers aboard Charles de Gaulle have since recovered from the disease except for one sailor, who was still hospitalized after leaving the ICU.

Netherlands

HNLMS Dolfijn

On 30 March 2020, the Ministry of Defence reported that eight crew members of the Dutch submarine had tested positive. Out of 58 crew members, 15 sailors with mild symptoms were tested. The submarine changed course near Scotland to return to the Netherlands two weeks early, arriving in Den Helder on 3 April.

Philippines BRP Jose Rizal

On , Navy Chief Vice admiral Giovanni Bacordo announced that one of the 65 crew members of the Philippine Navy missile frigate tested positive for COVID-19, causing the postponement of the ship's commissioning. The frigate had sailed from Hyundai Heavy Industries' shipyard in Ulsan, South Korea with its crew on 18 May. It had arrived at the Subic Bay anchorage area on 23 May and remained there to fulfill mandatory quarantine and swab testing requirements. The ship docked at the Port of Subic Bay in Zambales on but the whole crew had to undergo 14 days of additional quarantine from the time the ship's sole case tested positive. The ship was eventually commissioned on in a ceremony that was remotely attended by President Rodrigo Duterte.

On , the Philippine News Agency reported that, following the commissioning ceremony, two crew members of BRP Jose Rizal had tested positive for the virus and had been evacuated to a quarantine facility on shore.

Taiwan

ROCS Pan Shi

On 18 April 2020, Minister of Health and Welfare Chen Shih-chung reported that three Republic of China Navy cadets, interning on one of the ships of the , had tested positive for coronavirus. All three cadets were in their 20s, with one case showing symptoms as early as 12 April before seeking medical attention on 15 April, when the ship returned to Taiwan. There were 337 people aboard the same ship as the cadets. Over 700 sailors serving in the three-ship fleet have been placed in quarantine.

A Dunmu fleet is formed annually, and this iteration of the Dunmu fleet was formed on 20 February 2020 consisting of the following three ships: ROCS Pan Shi (磐石), a fast combat support ship and the flagship of the fleet, , a frigate, and , a frigate. The three cadets had boarded the ship on 21 February, and the fleet left Zuoying Naval Base on 5 March 2020 for a goodwill visit with Palau. The fleet stayed at Palau from 12 to 15 March 2020, although the size restrictions at the port in Palau meant that only Kang Ding entered the port. After departing Palau, the fleet remained at sea for roughly a month before returning to Zuoying Naval Base on 15 April.

On 19 April, Taiwan announced that a further 21 sailors of the Dunmu fleet had tested positive. More cases from Pan Shi continued to be identified, eventually reaching a total of 36. On 26 May, Chang Shan-chwen, an adviser to the Central Epidemic Command Center, stated that the index case on the Pan Shi was likely to have been infected in Taiwan.

The goodwill mission has been criticized for pictures of sailors not wearing masks appearing on social media. Vice Admiral Mei Chia-shu, Navy Deputy Commander, stated that as Palau had no reported cases of coronavirus at the time, such a decision was made after consulting with Taiwan's embassy in Palau.

United States

On 23 April 2020, the United States Navy reported that at least one coronavirus case had been found on 26 of its battle force ships. In addition, on 28 April 2020, the Navy reported that "[o]f the more than 90 U.S. Navy ships at sea around the world today, none have active COVID-19 cases".

USS Boxer

The coronavirus pandemic was reported to have spread to the American amphibious assault ship when its first presumptive positive case was reported on 15 March 2020. This was reported as the first case for a sailor aboard a United States Navy ship. The sailor subsequently quarantined at home. A second sailor tested positive on 17 March 2020 and also quarantined at home.

USS Essex

The coronavirus pandemic was reported to have spread to the crew of the American landing helicopter dock when its first case was reported on 17 March. The sailor had been attending a course at Naval Base San Diego since 6 February 2020 when the test returned positive on 14 March. The student subsequently self-isolated at home.

USS Ralph Johnson

On 17 March 2020, United States Pacific Fleet reported that a crew member of the American destroyer had tested positive the previous day. USS Ralph Johnson was at its home port in Everett, Washington at the time, and the sailor self-isolated at home. USS Coronado

On 17 March 2020, United States Pacific Fleet reported that a crew member of the American littoral combat ship had tested positive that day. USS Coronado was at its home port in San Diego, California at the time, and the sailor self-isolated at home.

By , nine sailors had tested positive, and more than thirty sailors, or roughly half of the crew, had their movements restricted.

USS Carl Vinson

The coronavirus pandemic was reported to have spread to the crew of the American aircraft carrier when its first case was reported on 23 March 2020. At the time, the ship was in dry dock at Puget Sound Naval Shipyard, and it was reported that "the sailor did not board the vessel and had no contact with any shipyard personnel".

USS Theodore Roosevelt

The coronavirus pandemic was reported to have spread to the American aircraft carrier when its first three cases were reported on 24 March 2020. As of 5 May 2020, 1,156 crewmembers have tested positive, with one fatality. The Navy has said they will no longer report public tallies of coronavirus cases on the USS Theodore Roosevelt. Initial testing was completed by 27 April 2020, at which point, 969 crew members had tested positive, and 14 of those 969 had recovered. By 29 April 2020, the bulk of the ship had been cleaned, and sailors that were previously quarantined on Guam began moving back to the ship.

This was the first instance of coronavirus being found aboard an American naval ship that had been deployed.

USS Ronald Reagan