WHO investigating hantavirus outbreak on The Hondius ship after Antarctic voyage, passenger infected before departure. Antarctic tourism surged tenfold in 30 years, with 80,000 tourists in 2024. Crews and passengers scrub equipment to prevent invasive species, especially after bird flu incident. Claire Christian advocates stricter environmental protections at Antarctic Treaty Consultative Meeting. Hanne Nielsen predicts annual visits could quadruple to over 400,000 in next decade