Updated

With the egg recall reaching 380 million and still spreading from state to state, Americans are paying special attention to a microscopic invader that can wreak havoc on the human body_ Salmonella.

It's rare to see a recall of this magnitude in the United States, but when we do, consumers are reminded that food-borne illnesses are more common than we think and we have to pay special attention to the way our meals are handled and prepared.

I've been getting a lot of e-mails about this recall, so I decided to answer some of your questions.

What is salmonella?

Salmonella refers to a group of bacteria that can cause salmonellosis in humans. There are more than 2,000 varieties of the bacterium, about a dozen of which are responsible for making us sick. Most often, salmonella infections cause gastroenteritis, or severe diarrhea. But in some cases, salmonella bacterium can also cause typhoid fever - a potentially deadly disease that is seen more in developing countries.

Salmonella bacteria have been known to cause illness in humans for over 100 years. Today, it is the most common form of bacterial food poisoning infecting millions of Americans each year, according to estimates from the Centers for Disease Control and Prevention (CDC) - with millions more cases going unreported.

How do people catch salmonella?

Salmonella bacteria live in the intestinal tracts of humans, birds and other animals. Most people become infected with salmonellosis by eating foods that are contaminated by feces, raw or undercooked meat, poultry or eggs. After they are ingested, the microscopic organisms begin to multiply in the digestive tract of the unsuspecting host within about 12 to 72 hours causing diarrhea.

This most recent outbreak involves eggs, so it's important for consumers to remember that while an egg's shell may seem like great protection from contamination, infected chickens can produce eggs that contain salmonella before the shell is even formed.

Who is at risk for catching salmonella?

Stomach acid is our bodies' natural defense against bacteria we ingest. But some people are at higher risk for developing a bacterial salmonella infection:

--People with stomach or bowel disorders --People taking antibiotics or antacids --People who own reptiles or birds --People with compromised immune systems --Young children and the elderly --People who travel internationally and to developing countries --People living in large groups

How do I know if I'm infected?

Salmonella can be diagnosed with a simple stool sample test. Sometimes it may go undiagnosed because the patient may have expelled all traceable amounts of the bacteria in the stool by the time they make it to the doctor for testing. If your doctor suspects a salmonella infection has entered your bloodstream, he or she may take a blood test.

The incubation period for the infection can be anywhere between 12 and 72 hours, and symptoms can include: --Abdominal cramping --Vomiting --Diarrhea --Fever/chills --Headache --Blood in the stool

Salmonella infections usually clear up on their own within about a week of the onset of symptoms, with lots of rest and a healthy amount of fluids to avoid dehydration and other secondary complications. Over-the-counter antidiarrheal medications can help calm the stomach, but doctors may prescribe antibiotics to kill bacteria in the bloodstream.

How can I protect myself from this salmonella outbreak?

Since eggs are the culprit with this most recent salmonella outbreak, it's important you take precautions when preparing them. Be sure to cook your eggs at temperatures of 72 degC/160 degF or more to kill salmonella bacteria that may be present in them.

Until the recall is over, health officials suggest avoiding foods like homemade Hollandaise sauce, Caesar and other homemade salad dressings, tiramisu, homemade ice cream, homemade mayonnaise, cookie dough, and frostings. They are also advising consumers to check the end of their egg cartons batch numbers 1026, 1413 and 1946, with date codes ranging from 136 to 225.

Which brands of eggs are currently involved in the recall?

Health officials linked eggs from Wright County Egg in Galt, Iowa, to several illnesses in the three states. The eggs were distributed around the country and packaged under the names Lucerne, Albertson, Mountain Dairy, Ralph's, Boomsma's, Sunshine, Hillandale, Trafficanda, Farm Fresh, Shoreland, Lund, Dutch Farms and Kemp.

Eggs affected by the expanded recall were distributed to food wholesalers, distribution centers and food service companies in California, Colorado, Minnesota, Arkansas, Arizona, Georgia, Illinois, Iowa, Oklahoma, Oregon, Missouri, Nebraska, Nevada, Texas, Utah, Washington and Wisconsin.