Brucellosis - Symptoms, Complications, Diagnosis, and Treatment

What Is Brucellosis?

Brucellosis is an extremely contagious bacterial infection caused by a group of bacteria belonging to genus Brucella. It is also known as Mediterranean fever, undulant fever, or Malta fever. The disease is named after the discoverer of the bacterium “David Bruce” in 1887. The name “Malta fever” is derived from the geographic endemic region where the fever is originally described. Animals are primarily infected from this bacteria, but the infection can spread to humans and can potentially affect almost all the organs of the body. This bacteria mainly infects cattle, sheep, dogs, camels, pigs, and goats. Humans commonly get infected by eating uncooked or undercooked meat and unpasteurized milk obtained from infected animals. The species Brucella melitensis is responsible for most of the cases of human brucellosis. The bacteria can also enter through an open cut or wound, or you can inhale it through the air. Veterinarians, butchers, and people who work with animal carcasses are at higher risk of brucellosis.

It is rare in developed countries like the United States, but brucellosis outbreaks are reported globally in most other countries. The symptoms include influenza-like symptoms and weight loss. This infection is treated with the help of antibiotics, but the symptoms of brucellosis can recur after months or years. Medicine does not cure it forever. So the best way to protect yourself is by avoiding the consumption of raw meat and unpasteurized milk products. Wear protective clothing when working with live or dead animals.

How Is Brucellosis Transmitted?

Many wild and domestic animals, such as cattle, sheep, goats, pigs, wild hogs, bison, camels, moose, hunting dogs, deer, etc., can get infected. The common seal, aquatic mammals that look like dolphins (porpoises), and some whales also get infected with Brucella species. Humans can get infected by:

1) Raw Meat or Unpasteurized Dairy Products:

Consuming undercooked or raw meat of infected animals, or drinking their milk without pasteurizing it first, are the primary ways through which this contagious bacteria spreads. Milk from infected goats, cows, sheep, or camels contain Brucella, and drinking it without boiling it long enough to kill the pathogens can infect you. Making cheese and other milk products without pasteurizing the milk first can also spread the bacteria. Remember to cook meat long enough for the core temperature to reach 145 to 165 ℉. Anything under this temperature is too low to kill the pathogenic organism present in it.

2) Inhalation:

You can also inhale the bacteria as Brucella easily spreads through the air. This puts people who work closely with animals, such as veterinarians, butchers, hunters, and laboratory workers, at risk of getting infected.

3) Skin Wounds or Cuts:

While handling infected animals, the bacteria can enter your body through any cuts or wounds that are uncovered or exposed. Infected animals’ urine, blood, semen, milk, saliva, aborted fetuses, birthing tissues, and all other bodily fluids contain Brucella, which puts people who take care of domestic animals and assist them during birth at high risk.

4) Human-to-Human:

Brucellosis does not usually spread from one person to another, but newborns can get infected through mothers during delivery or breastfeeding. Sexual transmission is rare. It is possible to get infected through blood transfusion or organ transplantation, but it is extremely rare.

Who Is at Risk of Getting Infected With Brucellosis?

Brucellosis is an occupational hazard for people who are in contact with animals, such as:

1. Dairy farmers.

2. Butchers or slaughterhouse workers.

3. Meat-packing employees.

4. Hunters.

5. Ranchers.

6. Microbiologists.

7. Veterinarians.

8. Laboratory workers.

Brucellosis affects individuals of all ages and both sexes. This infection is common in:

1. Africa.

2. The Middle East.

3. Southern and Eastern Europe.

4. Mexico.

5. South America.

6. Asia.

7. The Caribbean.

What Are the Symptoms of Brucellosis?

Brucellosis can infect any organ, and may present with a variety of symptoms, depending on the infected organ. Patients typically present with a fever that can be acute (<2 months), subacute (2 to 12 months), or chronic (>1 year). The fever is typically normal during the early part of the day and rises during the night so called 'swinging pyrexia.’ Brucellosis is one of the common causes of pyrexia of unknown origin.

Other symptoms include:

• Chills.

• Sweats.

• Loss of appetite.

• Back and body pain.

• Weakness.

• Fatigue.

• Headaches.

• Abdominal pain.

• Joint pain.

• Weight loss.

Joint and back pain may be the first manifestations of brucellosis, and is seen in up to 40 % of cases. In most cases, the symptoms disappear for weeks or months and then recur. And in some, the symptoms last for years, even with treatment, called chronic brucellosis. Chronic brucellosis can lead to many complications, which can also be fatal. As brucellosis mimics the flu, it is hard to differentiate the symptoms during the early stages.

How Is Brucellosis Diagnosed?

Consult a doctor if you are experiencing prolonged flu-like symptoms and if you work closely with livestock. Brucellosis is diagnosed preliminarily by the patient's history of exposure to likely sources of Brucella and the patient's clinical symptoms. Confirmation of the diagnosis is made by culturing Brucella from the patient. In addition, there are serological tests for the organisms done on the patient's blood specimens. These tests look for IgM or IgG antibodies directed against the bacteria. However these tests are confirmed by a Brucella-specific agglutination test. These tests help differentiate brucellosis from other diseases that may produce similar symptoms. If needed, you might also have to get:

1. X-rays - to check for changes in the bones and joints.

2. CT scan (computerized tomography) or MRI (magnetic resonance imaging) - to look for inflammation of the brain or spinal cord.

3. Cerebrospinal fluid (CSF) culture - CSF, which is the fluid that surrounds the brain and spinal cord, is collected and checked for infections.

4. Echocardiography - to check for signs of infection or heart damage.

How Is Brucellosis Treated?

Treatment is usually done with a combination of Doxycycline and Rifampin for an extended period (about six to eight weeks). The aim of treatment is to relieve symptoms and avoid complications. It is possible that the symptoms may not go away totally even after treatment.

What Are the Complications of Brucellosis?

Long-term or chronic brucellosis can affect the heart, brain, reproductive system, and almost all other organs in the body. The common complications of brucellosis are:

1. Arthritis - Brucella can infect joints and result in pain and inflammation. The joints that are commonly affected are knees, ankles, hips, and spine, which results in joint stiffness and pain.

2. Epididymo-Orchitis - The inflammation of the testicles or testes, which can also result in infertility. Epididymis, the tube that connects the vas deferens and testicles, can get infected by Brucella, spreading to the testicles, resulting in pain and swelling.

3. Spondylitis - Inflammation of the vertebrae, which are the joints between the bones in the spine.

4. Endocarditis - Infection of the inner lining of the heart, which can be potentially fatal as the heart valves might get destroyed. It is the most serious complication of brucellosis.

5. Hepatosplenomegaly - Inflammation and enlargement of the spleen and liver. This affects the liver functions and can lead to jaundice.

6. Meningitis and Encephalitis - Inflammation of the brain, spinal cord, and the surrounding membranes, which can be fatal.

Do’s and Don’Ts for Brucellosis?

As there is no human vaccine against brucellosis, the only and the best way to prevent this infection is by:

1. Avoiding contact with domestic and wild animals while traveling to countries or places where brucellosis outbreaks are common.

2. Wearing protective clothing while working with animals.

3. Covering up any wounds or cuts with plaster before touching animals.

4. Cooking meat until the internal temperature reaches 63 to 74 ℃.

Do not:

1. Drink unpasteurized milk.

2. Eat dairy products, such as cheese and ice cream, made from raw milk.

3. Eat raw or undercooked meat.

4. Forget to vaccinate domestic animals.

For more information on brucellosis, consult a doctor online now.