A ship that carried at least two malaria victims moved Thursday from Belle Chasse to the Port of New Orleans.
As the ship got closer to the city, parish officials consulted with mosquito experts to see if there was any threat.
The It is a ship's arrival Wednesday in Belle Chasse prompted a response from the Centers for Disease Control after two passengers were found to have malaria and two others with mild symptoms.
The vessel Marine Phoenix had made stops in the Congo and Central America. It was checked out, and while Ebola has been ruled out, parish leaders worry that the presence of malaria, which is spread by mosquitoes, could pose a different threat.
"[The are] a lot of questions about whether the mosquito that bit that man could've been transported onboard the ship," said Plaquemines Parish President Billy Nungesser.
That would be extremely rare. Only one in 20 mosquitoes is the species that carries the disease, and given the ship's schedule and an incubation period of about 15 days, transmission is highly unlikely.
"The likelihood is they got the disease prior to getting on the boat," said Steven Pavlovich, with Mosquito Control Inc.
City leaders are paying attention.
"It's highly unlikely that there will be any transmission, and the public is safe. We will continue to monitor," said New Orleans mayor Mitch Landrieu. Parish officials have consulted with Mosquito Control Inc., which is stepping up spraying in Jefferson Parish.
"The stepped-up efforts can't hurt, but really the general mosquito control we're taking should alleviate any concern about that," said Pavlovich.
Mosquito control officials say the bigger risk is if the malaria-carrying mosquito, bit one of the victims in New Orleans.
"The way it would be transmitted is by an anopheles mosquito biting someone infected from the disease, going through incubation, then transmitting to a human," said Pavlovich.
For now, officials say the proper precautions have been taken, and the risk of a spread of malaria is extremely small. Worldwide, there are about 300 million cases of malaria each year, and about one in 500 patients die.
The Centers for Disease Control and Prevention was formed in the 1940s with a primary focus on dealing with malaria. By 1951, thanks to in large part to DDT spraying efforts, the CDC declared that malaria had been eliminated in the United States.