We just did a 28 day cruise of Indonesia and Australia. We didn't get Covid, and have never had it. Most people on our ship did not wear masks; it was at times required and at other times recommended on tenders and buses; most did not comply, some put on a mask to get on the tender but then immediately took it off when they sat down. In Indonesia there was daily PCR testing and an unknown small number of passengers were in isolation. In Australia, no testing was done, and there was a lot of coughing on board. We avoided Covid by 1) getting the bivalent booster in September, 2) wearing well fitting N95 masks when around people, 3) always eating outside on deck, and avoiding high indoor spaces like elevators whenever possible, and, of course, 4) being lucky, considering the current high case numbers in Australia. The most risky environment on the trip were bus rides and especially airports. Really good N95 masks, like 3M masks, that fit properly, work far better than surgical masks, but you have to be pretty obsessive about wearing them. And there is emerging evidence that the bivalent booster is more effective against current Covid strains, which makes total sense since the virus has changed so much since January of 2020, and that if boosting is recent, you're more likely to have neutralizing antibodies titers sufficient to reduce the risk of infection. About 1/2 the people that we personally know to been on cruises in 2022 have gotten Covid during or immediately after the trip. Hand washing is good for preventing transmission of Norovirus, but does little to prevent Covid.
