Summer vacations are upon us, and a University at Buffalo professor is offering some advice to those planning to travel internationally: Be careful of the water.

“I tell our students who travel to these areas: ‘Do not put a drop of local water in your mouth,’ ” said John A. Sellick Jr., a member of the Infectious Diseases Division of the UB School of Medicine and Biomedical Sciences.

“Outside of the U.S., Canada, western Europe, Japan, Australia and New Zealand, hepatitis A and typhoid fever are present in much of the world,” said Sellick, who is also staff physician at the UB Student Health Services.

Both are typically spread by contaminated food and water.

He added, “Many providers will tell you that most international travel is no big deal and requires no special precautions, but I always have some students who come back to UB with infections after traveling abroad. Most are not life-threatening, but why take the chance?”

Sellick recommends that people contemplating international travel contact a travel clinic. The clinics specialize in providing appropriate immunizations and counseling about precautions and risks in specific regions of the world.

Even those traveling to major tourist destinations in the Caribbean and Latin America should check with a travel clinic, Sellick said.

Along with hepatitis A virus and typhoid bacteria, many other infectious agents are transmitted by water.

“Consume only boiled, bottled (major brand) or carbonated beverages,” Sellick said. Freezing does not kill infectious agents, so do not drink anything with ice.

Sellick sums it up: “Go on your vacation. Have a great time. Don’t come back sick.”