Summarize the following:
Fever, muscle aches, nausea and diarrhea are all common symptoms of listeriosis. In more severe cases, the infection may spread to your nervous system, leading to a stiff neck, a headache, loss of balance, convulsions, and/or an altered level of consciousness.  If you notice any of these more severe signs that indicate a possible spread to your nervous system, seek medical help immediately. When Listeria infects the nervous system, it could be meningitis (which simply means an infection of the central nervous system, specifically of the meninges) which always requires emergency medical care. If you have only the basic symptoms of fever, muscle aches, nausea, and/or diarrhea, you can most likely recover without the help of a physician — unless you are in the high-risk category (e.g. pregnant women, very young or very old, immunocompromised), in which case you must seek prompt medical attention. If you do not fall into any of the high-risk categories and appear to have only a mild listeriosis infection (which is the case for the vast majority of people), your doctor will likely advise that you rest and allow your immune system to naturally fight off the infection. It should resolve itself within a few days time, as your body fights it off just like it would any other mild infection. As with all infections, taking it easy and getting plenty of rest gives your body the best chance to recover quickly and without complications. Resting, and staying home from work or school, allows your body to devote all of its energy to healing (and when your immune system works to fight off an infection it takes more energy than you might expect!) Fighting off an infection also predisposes you to becoming dehydrated, so drinking plenty of fluids is key. Water and/or electrolyte beverages (such as Gatorade or other sports drinks) are best. Electrolyte beverages can help to increase your hydration because the salt content helps your body to readily absorb more water. Consuming vitamin C may also help to boost your immune system when you are sick. Echinacea tablets or teas and zinc may also help as natural ways to boost your immune system; however, neither have been validated in official medical trials.

Summary:
Recognize the signs and symptoms of a Listeria infection. Allow your immune system to combat the infection naturally. Get plenty of rest. Drink plenty of fluids. Boost your immune system.