You’re considering taking your kids on a cruise but then you hear about yet another outbreak of intestinal disease aboard a large ship. Do you go? It’s your decision. Here are the facts. My recommendation is below.
1. About 14 million passengers, including 1.5 million children, sailed from American ports last year. And, as in previous years and in spite of the best efforts of the U.S. Centers for Disease Control (CDC) and the cruise industry, some passengers became ill with intestinal illnesses, mostly due to the norovirus. Young children appear more susceptible to this virus than adults.
2. On cruise ships, most cases of norovirus result from placing your fingers/hands in your mouth after touching virus-contaminated objects – other people’s hands and doorknobs, for example. A less likely source of norovirus on cruise ships is ingesting virus-contaminated food and water. The virus can survive for 12 hours on most surfaces and up to 12 days on contaminated fabrics. It takes relatively few viruses to make people ill, far fewer than for other intestinal illnesses.
3. Cruise ships are ideal places for outbreaks.Thousands of passengers and crew are confined in relatively close quarters for many days. They touch the same objects and eat food and drink water from the same sources. One infected individual can spread the virus widely. The virus is often brought aboard unwittingly by passengers or crew, often at ports where sanitation is poor and the virus more common. Once aboard ship, it is difficult to eradicate.
4. Outbreaks on cruise ships are widely reported. The medical staff must document passengers and crew who visit the ship’s infirmary with intestinal symptoms or who ask for medication for such illnesses. Since the symptoms of norovirus generally occur within two to three days of infection, most victims are still aboard ship when symptoms appear. If the number of ill individuals surpasses 3%, the outbreak is reported to the CDC immediately, special sanitizing programs are instituted on the ship, and the ship is inspected when it reaches port. Ships are also inspected twice yearly (often unannounced) and are barred from sailing if they receive a failing sanitary score. Outbreaks and scores are posted on the CDC’s website (see below) and often widely publicized by the media.
5. Cases of norovirus are far more common on land. Last year, in the U.S., there were 21 million reported cases of food-related intestinal illnesses. Of these, norovirus accounted for more than half. However, far more cases go unreported. Physicians need not report cases to health authorities, and almost never do. Moreover, when outbreaks occur at restaurants, diners scatter after meals, and the outbreak goes unreported.
6. The majority of norovirus cases are merely annoying. Symptoms generally include mild diarrhea and stomach discomfort for a day or two. Vomiting occurs occasionally, especially in children. Children who drink and eat normally and are happy and playful need not be treated, even when symptoms last a few days. But these children should be isolated to avoid spread. No swimming. No playgroups. Seek medical care if children have frequent vomiting and diarrhea, are cranky and listless, and refuse liquids.
7. Proper and frequent hand washing greatly reduces the chances of illness. The CDC recommends the following:
Wet hands with clean, running water (warm or cold). Turn off tap. Apply soap. Lather by rubbing hands together. Lather back of hands, between fingers, and under nails. Scrub for at least 20 seconds. (Hum “Happy Birthday” twice.) Rinse under clean, running water. Dry with clean towel or air dry.
8. Use soap and water if possible, not hand sanitizer, to clean hands. When soap and water are not available, use alcohol-based hand sanitizers that contain at least 60% alcohol. Compared to soap, sanitizers remove fewer types of disease-causing organisms, are less effective when hands are visibly dirty, and can cause alcohol poisoning when swallowed. Read instructions.
9. Choosing cruise ships by their sanitary score is not helpful in avoiding illness. Ships’ current and past sanitation scores are available at http://www.cdc.gov/nceh/vsp/surv/gilist.htm. However, there is little correlation between scores and risk of illness; outbreaks occur on ships with perfect scores. The same is true for avoiding leafy salads and shellfish, for example, foods associated with norovirus outbreaks on land.
10. My opinion: Most types of travel and many outdoor recreational activities – camping and swimming, for example – increase the incidence of intestinal diseases. Chances of illness aboard cruise ships are small and in most cases of illness, symptoms are mild. And there is “in-house” medical care available on ships. Even staying home has its pitfalls. Young children average two episodes of intestinal diseases yearly, more if they attend daycare or nursery school. So taking children on cruises is a reasonable travel decision. Bon voyage.
