(CNN)More than 20 Covid-19 cases have been identified aboard an Australian navy ship sailing to disaster-hit Tonga, complicating aid efforts to the virus-free Pacific island nation as Japan halted its relief mission due to a separate outbreak among crew members.
Tonga has only reported a single coronavirus case since the start of the pandemic and is making every effort — including insisting on contactless delivery — to keep Covid-19 out as it receives aid from its Pacific neighbors following a massive volcanic eruption and tsunami nearly two weeks ago.
Australia’s Defense Minister Peter Dutton told a news conference Tuesday that 23 cases have been detected on the HMAS Adelaide, from a crew of more than 600 people. The ship left Brisbane on January 21, carrying humanitarian aid and medical equipment, and was due to arrive in Tonga this week.
The infected crew are in isolation and aren’t showing severe symptoms, Dutton said, adding the ship will deliver its supplies quickly given permission to dock in Tonga.
“We can do that in a contactless way, spray the equipment, so the chance of passing on the virus is obviously negligible,” he said.
It comes as Japan’s Defense Ministry said Tuesday it had suspended an aid mission to Tonga after four Air Self-Defense Force members stationed in Australia tested positive for Covid-19, according to public broadcaster NHK.
NHK reported that a member of the relief unit tested positive for the virus on Monday after Japan delivered the first batch of drinking water to Tonga on Saturday. Three more crew members tested positive Tuesday, NHK said, citing the ministry.
Japan is now unable to transport supplies from Australia to Tonga and is considering sending replacements for more than 30 crew members now in isolation, NHK reported.
The eruption of the underwater Hunga-Tonga-Hunga-Ha’apai volcano on January 15 left much of the Tongan archipelago covered in thick ash, and triggered a tsunami that sent waves crashing into islands. At least three people were killed in the disaster.
The first contactless aid flights arrived in Tonga from Australia last week as part of efforts to prevent Covid-19 spreading in the nation.
Tonga, which has a population of more than 100,000 people, has fully vaccinated more than 80% of its eligible population, according to the World Health Organization.
“Under no circumstance will we compromise the health and wellbeing of those Tongans who have already had a concerted effort against the virus by protecting themselves, and the virus is not present on the island,” Australian Defense Minister Dutton said Tuesday.
Other countries including New Zealand have also sent supplies to the remote nation, which was almost entirely cut off from the world in the immediate aftermath of the blast due to damage to a key underwater cable.
Aid agencies and Tongan politicians have warned of water contamination and potential food shortages after crops were ruined by the ash.
Rescue workers are working to deliver safe drinking water to the islands, as communications gradually resume and cleanup efforts continue.