Within 24 to 48 hours of the first detection of the virus, state and federal animal health officials work with farms to cull infected flocks to reduce the risk of transmission. That’s followed by extensive disinfection and months of surveillance and testing to make sure the virus isn’t still lurking somewhere on-site.

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This norovirus case marks the seventh gastrointestinal illness outbreak on cruises this year that reached the CDC's threshold for public notification.

Consumers are still facing egg shortages and price rises as the ramifications of Australia's largest bird flu outbreak continue to be felt.

“Due to ongoing issues with the supply of eggs, we are currently limiting egg purchases to one dozen per customer, per day, in all Trader Joe’s stores across the country,” a Trader Joe’s spokesperson told CNN. “These limits will help to ensure that as many of our customers who need eggs are able to purchase them when they visit Trader Joe’s.”

Egg prices are soaring across the country, largely because of avian influenza. Ohio remains the hardest-hit state.

Between November and December, the price of eggs has increased due to an egg shortage caused by the spread of avian influenza, or bird flu. According to the Bureau of Labor Statistics, as of February 7, the cost has nearly doubled from a year ago.

The price hike is largely due to the impact of bird flu on the U.S. The CDC says more than 156 million poultry birds have been affected. As consumers see the impact on their grocery bills, local producers are also affected due to a decline in profit and the loss of their animals.