So you finally booked that Caribbean cruise. Splurged on a sexy new bikini. Picked up a paperback of that steamy best-seller.
While you're shopping for sunscreen, you also may want to consider a few items to help keep you on deck instead of in the sick bay: in particular, antiseptic wipes and anti-diarrheal medication.
Winter marks the height of cruise season, and coincidentally, a time when gastrointestinal illnesses make their rounds among people in close quarters.
After years of battling the problem, the U.S. Centers for Disease Control and Prevention (CDC) and the cruise industry have developed more aggressive sanitation measures to help keep passengers healthy.
Their biggest foe: a common stomach bug on cruise ships called norovirus (Norwalk-like virus), which causes diarrhea, stomach cramps and vomiting.
Although symptoms generally fade away in a day or two, the germs are highly contagious and can survive on inanimate surfaces for weeks at a time. In fact, the CDC tracked 13 outbreaks of norovirus aboard cruise ships in the first half of 2005 alone.
The illness can be transmitted by eating or drinking food or liquids infected with norovirus. But these days, passengers are more likely to carry the disease on board with them, says Dave Forney, chief of the CDC's Vessel Sanitation Program.
Forney's agency performs unannounced inspections of all cruise ships and records disease outbreaks on board. Norovirus, he says, "has really, seriously become a people problem. We are not tracing any illness lately to food or water."
Today's passengers generally plan their cruise long in advance, Forney says. And if they get sick just before sailing, they're more likely to take an over-the-counter anti-diarrhea medication and board the ship instead of canceling their trip.
The virus is shed through waste and "Americans are not good hand washers," Forney says, "so if you're the unlucky person who touches the same doorknob or handrail after the person who is sick," you may catch it, too.
Compounding the problem, passengers who get sick don't necessarily tell the ship's medical staff, who are required by law to log and report the number of passengers and crew with symptoms of gastrointestinal illness.
So the CDC also relies on cabin stewards to report incidents of vomiting and diarrhea. Investigators step in to help when 2 percent or more of passengers or crew become ill -- or if an unusual gastrointestinal pattern or characteristic is found.
"In 2002 or 2003 ... we could almost guarantee that if someone got sick on a cruise one week, more people would get sick during the next cruise," Forney says. "Now, by immediately initiating extra sanitation measures, usually the number of cases drops dramatically by the end of the cruise. That's the best evidence that it's working."
The CDC estimates that 23 million Americans -- one in every 12 -- contract norovirus each year, generally in close quarters such as dormitories and nursing homes. Of the 8 million passengers who cruise from U.S. ports annually, only one in 3,600 comes down with the symptoms, the agency estimates.
However, increasing outbreaks of norovirus aboard ships have been reported since 2001, in part because more passengers are sailing on more ships, the CDC reports.
By 2004, there were 192 cruise ships carrying 10.85 million passengers worldwide, according to the International Council of Cruise Lines, which represents 16 major cruise companies. Of those, about 105,000 embarked through Baltimore's cruise port in Dundalk.
Over the past three years, cruise lines have become even more vigilant in their cleaning efforts, according to Christine Fischer, a council spokeswoman.
Ship crews use an arsenal of cleaners that kill norovirus, including chlorine. They also use disinfectants on counters, bathroom surfaces, door handles, railings and grab bars, exercise equipment, video arcade equipment, vanities and TV remote controls.
Some crews go so far as to sanitize individual Scrabble game tiles and poker chips, and throw out playing cards after each evening in the casino.
To reduce the risk of spreading the virus, staff no longer shake hands at cocktail parties, and on some lines the days of self-serve buffets are over. Passengers now point to the food they want and staff members serve them.
In addition, on turn-around days, extra crewmembers are brought on board to disinfect the ship before new passengers board.
Cruise lines also have begun an aggressive communications effort on board ships to encourage passengers to wash their hands, Fischer says.
Local travelers have noticed these efforts.
Peg MacGloan, an Annapolis real estate agent, was leery of going on a Western Caribbean cruise in November with a group of more than 300 fellow real estate agents. But when a colleague pointed out that their Carnival cruise ship had a cleanliness ranking of 98 percent from the CDC, she "decided to go for it."