Transcript for Cruise ship quarantined amid measles outbreak
We turn now to the hundreds of passengers and crew reportedly trapped on a cruise ship this morning because of a measles emergency. That ship has now been quarantined on the caribbean island of St. Lucia after authorities confirm someone on board has the measles and others have likely been exposed. ABC's Victor Oquendo is live at the port of Miami. What can you tell us? Reporter: Well, good morning, David. St. Lucia's chief medical officer guiding not to take chances and following it in the United States and deciding to keep it quarantined and docked. A cruise ship with 300 people on board is under quarantine after a case of the measles was found. We got information early this morning through two sources, two reputable sources that there was a confirmed case of measles on board a cruise ship which visited our island. Reporter: The government of ain't Lucia ordering crew and passengers to stay on the ship while it investigates. The CDC is already tracking the worst spike in the U.S. In decades. More than 700 cases across 22 states. The outbreak mostly hitting people who are unvaccinated. First starts with cold symptom, fever, cough, runny nose and sometimes red eyes and that can last for about three to four days before the rash comes on, so if you haven't been vaccinated and you have what seems like a bad cold it actually might be measles. Reporter: One of the most highly contagious viruses in the wore. If an unprotected person is exposed they have a 90% chance of contracting the disease. It's a very, very contagious virus. It's probably the most contagious virus that humans Reporter: The quarantined ship the latest in an outbreak that officials are fighting to contain. Now an investigation is under way but in the meantime, no one is allowed to leave that ship. Robin. Understandable. Now to a scary bounce house
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