Norovirus Sickens 98 Aboard FL-Bound Cruise Ship, CDC Says

MIAMI, FL — A norovirus outbreak sickened nearly 100 people on a Royal Caribbean cruise ship en route from California to Miami, the Centers for Disease Control and Prevention said.

The Serenade of the Seas set sail from Sept. 19 in San Diego and was scheduled to make stops in the Mexico Riviera, Costa Rica, Colombia and Panama Canal before arriving Thursday in Miami.

Of the 98 people sickened with the virus, the CDC said Tuesday four of them were crew members. The more prevalent symptoms experienced were diarrhea and vomiting.

The CDC received notice of the outbreak on Sunday. The CDC's Vessel Sanitation Program is monitoring the outbreak.

Royal Caribbean expanded its cleaning and disinfection efforts, gathered stool samples for testing, isolated the passengers and crew members who were sick and consulted with the VSP regarding norovirus cases and sanitation cleaning measures due to the outbreak, the CDC said.

"The health and safety of our guests, crew, and the communities we visit are our top priority," Royal Caribbean Group said in a statement to NBC News. "To maintain an environment that supports the highest levels of health and safety onboard our ships, we implement rigorous cleaning procedures, many of which far exceed public health guidelines."

Norovirus is highly contagious and is spread through direct contact with someone who is sick, sharing food or utensils with them, touching surfaces contaminated with the virus and then touching their face or mouth, or by consuming contaminated foods or liquids.

Outbreaks are common in restaurants and catered events, schools and daycare centers, health care facilities, cruise ships, jails and any other place where people are close together.

Symptoms usually arise within 12 or 48 hours of becoming infected. The most common symptoms are diarrhea, vomiting, nausea and stomach pain, but also may include fever, headache and body aches.

There is no antiviral medication for norovirus. The most important thing is to make sure people who have it get plenty of liquids. People who have norovirus may vomit or have diarrhea several times a day and are at risk of dehydration — especially in young children, older adults and people with other illnesses.

Symptoms of dehydration include:

• Decreased urination
• Dry mouth and throat
• Feeling dizzy when standing up
• Crying with few or no tears
• Unusual sleepiness or fussiness

The best way to prevent norovirus is to wash hands in hot, soapy water for 20 seconds after using the toilet, changing diapers and before eating, preparing or handling food. Hand sanitizer isn’t particularly effective at controlling the spread of the virus.

Also, thoroughly wash fruits and vegetables, and to cook shellfish to an internal temperature of 145 degrees Fahrenheit to prevent norovirus contamination.