Small luxury operators have tried strict testing requirements and capacity limits, but onboard outbreaks persist.
Authorities around the world halted voyages on large passenger ships in March after Covid-19 tore through scores of vessels, but cruising never really stopped.
Smaller cruise ships exempted from the suspension continued to sail selected routes. To keep the deadly virus off ships, these boutique operators experimented with a variety of new precautions.
The result: They mostly failed.