Brucellosis is a common zoonotic infection caused by bacterial genus Brucella. Brucellosis is an old disease known by various names including undulant fever or Mediterranean fever. This is one of the infectious diseases transmissible between animals and humans.
Global distribution of Brucellosis-
This infection is more common in Mediterranean areas, the south and the center of America, Africa, Asia, Arab peninsula, Indian subcontinent and the Middle East. The maximum incidence in the world had been reported in Syria.
Brucellosis, undulant fever, Mediterranean fever, Cyprus fever, and goat fever.
- ‘Malta fever’ is a bacterial disease caused by various brucella species, which mainly infect cattle, swine, goats, sheep and dogs.
- Malta fever is transmitted to humans through direct and indirect contact with infected animals.
- Infection is most likely caused by ingesting unpasteurized milk or cheese from infected goats or sheep.
- It causes flu-like symptoms, including fever and lethargy.
- There is no human vaccine to prevent Malta fever, but it is important to take precautions to avoid it.
Malta fever is a bacterial disease caused by various brucella species. Infection is transmitted to humans through direct and indirect contact with infected animals. It mostly affects individuals who work in the livestock sector. The consumption of raw milk and cheese made from raw milk (fresh cheese) is the major source of infection in man; however, human-to-human transmission is very rare. On the other hand, Malta fever remains a problem globally, because it is the most common bacterial infection spread from animals to humans around the world, as animals may be carrying the bacteria without showing any symptoms of illness.
Types of Brucella bacteria:
Types of brucella bacteria:
There are 8 known species of the brucella bacteria, but only four of them cause brucellosis in humans:
- Maltese Brucellosis (B. melitensis): This type is the most common and most severe, and is found in lambs.
- Pig Brucellosis (B. suis): This type infects individuals who come in contact with animals. It has a severe impact on humans.
- Brucella abortus (B. abortus): It infects cows and is moderately severe.
- Canine Brucellosis (B. canis): It infects individuals who come in contact with dogs and is moderately severe.
Other animals are also considered a primary source of the Brucella bacteria, including wild animals.
Brucellosis is the result of being infected with the brucella bacteria.
- Humans contract brucellosis by consuming unpasteurized dairy products and undercooked or raw meat of infected animals.
- Direct contact with an infected animal or its bodily discharge (such as tissues, blood, urine, vaginal discharge, aborted fetuses, and placentas), via cracked skin, can also occur.
- The disease can also be transmitted to humans through inhaling airborne agents in barns, stables, and sometimes laboratory and slaughterhouse.
Rare Means of Transmission:
- From mother to fetus through the placenta
- Sexual contact
- Blood transfusion or marrow transplant from a person infected with Brucella
- Few cases result from accidental pollination of an animal with brucellosis.
Symptoms usually appear within 5 to 60 days, and sometimes they takes several months to appear.
Who is at risk?
- Livestock farmers
- Slaughterhouse workers
- Medical lab workers
Malta fever can cause several symptoms. Some of them last for a long period of time. Initial symptoms include:
- Loss of appetite
- Muscle, joint, and back pain
- Fatigue and lethargy
When to see a doctor?
When a rapid rise in temperature, muscle pain or unusual weakness and persistent fever occurs. It is also crucial to see your doctor if you are among the groups at a higher risk of contracting the disease.
- Endocarditis (an infection of the endocardium, which is the inner lining of the heart or valves)
- Orchitis (inflammation of the testicles)
- Spleen or liver inflammation
- Central nervous system inflammation.
- Clinical examination
- Laboratory tests: They involve searching for the bacteria in samples of blood, bone marrow, or other body fluids.
Treatment aims to relieve symptoms and prevent complications. It depends on the timing and severity of the disease. The disease may take a few weeks to several months to be cured. Patients take antibiotics for at least six weeks.
There is no human vaccine that can prevent Malta fever, so it is important to take precautions to prevent it with the following steps:
- Make sure to cook meat well at a temperature of 63-74°C.
- Do not drink or eat unpasteurized dairy products, including milk and cheese.
- Take safety precautions at workplaces (e.g. during handling samples in laboratories).
- Wash your hands before and after handling animals.
- Wear rubber gloves and protective clothing and glasses if you work in a field where you come in contact with animals.
- Ensure that wounds are covered with a bandage.
- How long do brucella bacteria live outside the body?
- Brucella bacteria are resistant to natural conditions, and they can survive for several hours up to over 60 days if the surrounding environment is moist.
- How long should meat be cooked?
- Meat and liver should be well cooked at 63°C for half an hour.
Women who are pregnant and have been exposed to Brucella should consult with their obstetricians/healthcare provider for evaluation. Prompt diagnosis and treatment of brucellosis in pregnant women can prevent complications including miscarriage.