Salmonella is a genus of rod-shaped Gram-negative enterobacteria that causes typhoid fever, paratyphoid and foodborne illness.

Disease causing salmonellae are in a class of species called salmonella enterica.

Salmonella enterica has numerous strains or serovars. Salmonella typhi is one of the well-known serovar. It causes typhoid fever.

Other salmonellae are frequent causes of foodborne illness, and can mainly be caught from poultry and raw eggs. They can also be caught from food that has been cooked or frozen, and not eaten straight away.

Salmonellosis or salmonella infection is the illness that can occur if live salmonella bacteria enter the human body. Salmonellosis is one of the most common bacterial food borne illnesses.

Children are the most likely to get salmonellosis. Young children, the elderly, and those with impaired immune systems are particularly susceptible to severe infections.

Salmonellosis is more common in the summer than winter and is contagious (can be spread from person to person).

Transmission of Salmonella

Salmonella live in the intestines of animals, birds and humans. Salmonella are transmitted to humans by eating foods contaminated with animal excrement.

Strains of the bacteria that cause no symptoms in animals can make people sick, and vice versa.

Contaminated foods are normally of animal origin and include beef, poultry, milk, and eggs. However, all foods including vegetables may become contaminated.

Food may also become contaminated by an infected food handler who did not wash his or her hands with soap after using the bathroom.

Contaminated food does not taste, smell, or appear different from uncontaminated food. Thorough cooking food kills the salmonella bacteria.

In addition to contaminated food, people are likely to get an infection through a reptile. Reptiles such as turtles, iguanas, lizards, and snakes often harbour salmonella.

You should always wash your hands immediately after handling a reptile even if the reptile is healthy. It is also important to ensure that children wash their hands after handling a reptile.

Salmonella Symptoms

Symptoms are usually gastrointestinal. The symptoms can be severe especially in the old and very young.

They appear 6-72 hours after ingestion of the bacterium and can last up to 7 days. These symptoms can include,

  • Nausea
  • Vomiting
  • Fever
  • Abdominal cramps
  • Diarrhoea
  • Headaches

    Salmonella Diagnosis

    Many types of illnesses can cause nausea, diarrhoea, fever, and other symptoms of salmonella. The determination that salmonella is the cause of the illness is dependent on laboratory tests.

    Salmonella can be identified if the laboratory is specifically instructed to look for the bacteria.

    Further testing can determine its type and the antibiotics that can treat it.

    Salmonella Treatment

    Most persons recover from salmonella without treatment.

    However, some patients may have severe diarrhoea and need hospitalisation due to dehydration.

    In such patients, the salmonella infection may spread from the intestines to the blood stream. It can then spread to other body sites and cause death unless the patient is treated promptly with antibiotics.

    Patients with severe diarrhoea require rehydration. Intravenous fluids are used for rehydration.

    Antibiotics may not be necessary unless the infection spreads from the intestines. It can then be treated with drugs such as ampicillin, gentamicin, trimethoprim/sulfamethoxazole, or ciprofloxacin.

    Some Salmonella bacteria have become resistant to antibiotics.

    Long-term Effects of Salmonella Infection

    A few individuals who get salmonella infection may experience Reiter's syndrome. Reiter's syndrome is characterised with pains in the joints, irritation of the eyes, and painful urination.

    It can last for months or years. This can cause long-lasting disabling effects such as arthritis.

    Chronic arthritis is difficult to treat. Antibiotic treatment of salmonella does not make a difference in whether or not the person later develops arthritis.

    Preventing Salmonellois

    There is no vaccine to prevent salmonellosis.

  • Given that foods of animal origin may be contaminated with Salmonella, you should not eat raw or undercooked eggs, poultry, or meat.

  • Poultry, meat and other products containing meat such as hamburgers, should be well cooked.

  • Do not consume raw or unpasteurized milk or other dairy products.

  • Do not eat or drink foods containing raw eggs.

  • Keep eggs refrigerated and throw away cracked or dirty eggs.

  • Produce should be thoroughly washed before consuming.

  • Cross-contamination of foods should be avoided. Uncooked meats should be kept separate from produce, cooked foods, and ready-to-eat foods.

  • Hands, cutting boards, counters, knives, and other utensils should be washed thoroughly after handling uncooked foods.

  • Hands should be washed before handling any food, and between handling different food items.

  • Wash hands, kitchen work surfaces, and utensils with soap and water immediately after they have been in contact with raw meat or poultry.

  • People who have salmonellosis should not prepare food under any circumstances.

  • People should wash their hands after contact with animal excrement.

  • People should immediately wash their hands after handling reptiles and birds since they are particularly prone to harbouring salmonella.

  • Reptiles are not appropriate pets for small children and should not be in the same house as an infant.

  • Be particularly careful with foods prepared for infants, the elderly, and the people with an impaired immune system.

  • Wash hands with soap after handling reptiles or birds, or after contact with pet excrement.

  • Avoid contact between reptiles and infants or people with weak immune systems.

  • Mother's milk is the safest food for young infants. Breast-feeding prevents salmonellosis and other health problems.

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