Seniors, pregnant women, and those with immune deficiencies are at the biggest risk

The Centers for Disease Control and Prevention (CDC) is investigating a multi-state outbreak of listeria infections linked to meats sliced at deli counters. The outbreak has claimed two lives and sent 28 others to the hospital.

This is one of at least five listeria outbreaks so far this year.

Investigators have yet to pinpoint the exact source, but most people who fell ill reported eating turkey, liverwurst, and ham usually in the first two weeks after consuming the meat.

The meats were sliced mostly at supermarket and grocery store delis in Illinois, New York, New Jersey, Minnesota, Wisconsin, Missouri, Georgia, North Carolina, Virginia, Maryland, Pennsylvania, and Massachusetts. The CDC has not yet identified specific stores or brands where the contaminated meat was sold.

Here's who is most at risk

The CDC says that the outbreak is extremely dangerous for people aged 65 and over, pregnant women, people over 65, and those with weakened immune systems.

If you are in one of those groups, the CDC recommends you take the following steps:

Do not eat meats you get sliced at any deli counter, unless it is reheated to an internal temperature of 165F or until steaming hot. Let it cool before you eat it.

Meat stored in the fridge?Listeria can grow on foods kept in the refrigerator, but it is easily killed by heating food to a high enough temperature. If you had any deli meat in your refrigerator, make sure you clean therefrigerator, and any containers and surfaces that may have touched sliced deli meats.

Call your healthcare provider right away if you have any of these symptoms:

• People who are not pregnant usually have fever, muscle aches, and tiredness. They may also get a headache, stiff neck, confusion, loss of balance, or seizures.

• Pregnant people usually have fever, muscle aches, and tiredness. However, Listeria can cause pregnancy loss or premature birth. It can also cause serious illness or death in newborns.

The CDC asks for your help

The CDC is asking the public to helpidentify the products and where they were purchased.

"If you are sick with Listeria, local or state health officials may contact you to find out what you ate in the month before you got sick," the agency said."They may also ask for copies of receipts, your shopper card number, or leftover food for testing."