Cruise Critic contacted the CDC for some clarification on blood donation issues and travel to Mexico as a result. Here's what we've learned:
If you visit the following areas, the waiting period applies: Playa Del Carmen, Calica, Mazatlan, Costa Maya and Puerto Chiapas.
Urban areas that are sprayed regularly are not at risk. Places of note without issue: Puerto Vallarta, Cancun, Cozumel, Acapulco and Cabo San Lucas (Guerrero, the Mexican state where Acapulco is located is labeled as "lower risk").
It is unlikely that cruisers stopping in a Mexican port for the day are really at risk to the same extent as the local population. The source of Malaria transmission is the female Anopheles mosquito, a nocturnal night-biting mosquito, and port calls are nearly unilaterally day-time affairs. All parties involved, however, including the Mexican Ministry of Health, the CDC and the Red Cross have decided on a very conservative approach to the situation.
The regulations are subject to change based on joint findings by the Mexican Ministry and the World Health Organization studies. We'll keep you posted.
--by Dan Askin, Editorial Assistant