Traveling overseas sometimes means the specter of infectious disease, such as the case of two Japanese men who died of rabies, one in November and the other in December, from separate dog bites in the Philippines.

Medical experts say there are five major areas of concern when traveling abroad. Most conspicuous is enteritis caused by Escherichia coliform bacillus, salmonella and norovirus. It is also called traveler's diarrhea because of its symptoms.

"About 10 percent of Japanese staying overseas for a week suffer from the disease. You should be on alert not only in developing but also in advanced countries," said Atsuo Hamada, acting director general of the Japan Overseas Health Administration Center at the Japan Labor Health and Welfare Organization.