Illness during vacation is costly.

If you ever have planned meticulously for that perfect vacation only to have it ruined by a nasty bout of sunburn or, worse, motion sickness, you're not alone. According to "Rx for Travel Health," a national survey of 1,000 travelers sponsored by Novartis Consumer Health, Inc., Summit, N.J., 63% reported they or a companion have gotten sick while on vacation. Adding insult to injury, a vast majority of the illnesses were preventable. The most common ailments included sunburn (62%), motion sickness or seasickness (34%), allergies (34%), diarrhea (23%), and food poisoning (12%).

Besides missed activities and disrupted sightseeing, there is a substantial financial downside to becoming ill while on vacation. Respondents who did not get sick spent an average of $1,021 on their last vacation; those who...