Staphylococcal food poisoning

Overview

Staphylococcal food poisoning results from eating food contaminated with toxins produced by certain types of staphylococci, resulting in diarrhea and vomiting. The staphylococci bacteria grow in food, in which they produce their toxins. Thus, staphylococcal food poisoning does not result from ingesting the bacteria but rather from ingesting the toxins that are already present in the contaminated food. Typical contaminated foods include custard, cream-filled pastry, milk, processed meats, and fish. The risk of an outbreak is high when food handlers with skin infections contaminate foods that are undercooked or left at room temperature.

Symptoms

Symptoms usually begin abruptly with severe nausea and vomiting starting about 2 to 8 hours after the contaminated food is eaten. Other symptoms may include abdominal cramping, diarrhea, and sometimes headache and fever. Severe fluid and electrolyte loss may cause weakness and very low blood pressure (shock). Symptoms usually last less than 12 hours, and recovery is usually complete. Occasionally, staphylococcal food poisoning is fatal, especially in the very young, the very old, and people weakened by long-term illness. The most common symptoms of food poisoning include diarrhea, watery stools, abdominal cramps, nausea, vomiting, and fever. Most food poisoning symptoms are mild, however, and can safely be treated at home. Salmonella. Food poisoning caused by Salmonella bacteria gives victims flu-like symptoms for as long as a week. Botulism. The first symptoms appear abruptly, usually 18 to 48 hours after the food was eaten. These symptoms include nausea, dry mouth, vomiting, abdominal pain and blurring of vision. The toxin has a paralyzing effect on the nervous system; it prevents the nerves from conducting messages from the brain. Control of the muscles is lost, beginning with those around the face and neck. Loss of the ability to swallow makes it impossible to eat. It leads to choking and may introduce foreign materials into the lungs. The victim usually dies within several days. If medical aid is quickly obtained and the correct diagnosis rapidly made, death can be avoided. A serum may be injected which is sometimes able to neutralize a portion of the toxin and limit further paralysis. This serum cannot help the nerves that are already damaged. The speed with which symptoms appear depends largely on the amount of toxin-containing food that is eaten. Staphylococcal food poisoning. This type of food poisoning is associated with abdominal cramps, fever, vomiting and diarrhea. It appears about 6 hours after eating food contaminated with an enterotoxin formed by the staph bacteria. Dairy products, pastries and fish are common foods harboring this organism.

Causes

The Centers for Disease Control estimates that unknown agents cause 81 percent of all food-borne illnesses and hospitalizations. There are more than 200 known diseases that can be transmitted through food, however, and the known causes of food poisoning include infective agents and toxic agents. Infective agents include viruses, bacteria, and parasites. Toxic agents include poisonous mushrooms, improperly prepared exotic foods (such as barracuda), or pesticides on fruits and vegetables. Food usually becomes contaminated with these agents from poor sanitation or preparation. Food handlers who do not wash their hands after using the bathroom or have infections themselves often cause contamination. Improperly packaged food stored at the wrong temperature also promotes contamination. Three of the most important causes of food poisoning are the salmonella, clostridium botulinum and staphylococcal organisms.

Prevention

Careful food preparation can prevent staphylococcal food poisoning. Anyone who has a skin infection should not prepare food for others until the infection heals. Food should be consumed immediately or refrigerated and not kept at room temperature.

Diagnosis

The symptoms are usually all a doctor needs to make the diagnosis of gastroenteritis. A more specific diagnosis of staphylococcal food poisoning may be suspected when other people who ate the same food are similarly affected and when the disorder can be traced to a single source of contamination. To confirm the diagnosis, a laboratory analysis must identify staphylococci in the suspected food, but this analysis is not usually performed.

Treatment

Treatment usually consists of only drinking an adequate amount of fluids. A doctor may give a drug, either as an injection or as a suppository, to help control severe nausea and vomiting. Sometimes so much fluid is lost that fluids have to be given intravenously.The most common treatment for simple food poisoning is simply supportive care at home with clear liquids to stay hydrated, and after vomiting or diarrhea subside, the gradual return to eating beginning with a bland diet (such as rice, bread, potatoes and milk). The doctor should be consultedalled if the person has nausea, vomiting or diarrhea that lasts more than 2 days, a fever, dizziness or unconsciousness, or if the symptoms are occurring after recent travel to foreign countries, or if people who ate the same thing are also ill. A visit to the hospital should be made if the person experiences vomiting blood, a swollen abdomen, problems breathing, swollen joints, yellow eyes or skin, or sharp abdominal pain that lasts more than 15 minutes.