Carnival sneezes, Royal Caribbean and Norwegian Cruise catch colds

• Carnival Corp is lower 4.75% after a downgrade to Underweight from Morgan Stanley, whose survey of cruise travel agents showed neutral to negative booking trends for the important month of August, with agents for the first time noting the Zika virus as hurting business.
• Royal Caribbean (RCL -2.4%), Norwegian Cruise (NCLH -3.4%)
• Fading the moves of those giants, though, is Lindblad Expeditions (LIND +1.9%).