Glanders And Melioidosis - Symptoms, Diagnosis, and Treatment

Introduction

Glanders and melioidosis are bacterial diseases caused by Burkholderia mallei and Burkholderia pseudomallei, respectively. They present with similar symptoms and are diagnosed and treated similarly; however, they differ with respect to their origin and spread. They have gained interest because of the study during world war I to use it as a possible biological warfare weapon conducted by the United States and other countries. Both organisms have been classified as category B priority pathogens by NIH (national institutes of health) and CDC (centers for disease control and prevention). They are considered potential warfare agents, especially in the aerosolized form, as they are highly infectious and are resistant to most antibiotics.

What Are Glanders?

Glanders is an infection caused by Burkholderia mallei and is commonly seen in horses. It may also be seen in donkeys, mules, goats, dogs, and cats; however, it is rare in humans. It may also be seen in people who stay in close contact with infected animals, such as veterinarians, animal caretakers, laboratory technicians, etc.

What Is Melioidosis?

Melioidosis, also known as Whitmore disease, is a bacterial infection caused by Burkholderia pseudomallei and is contracted by animals and humans through direct contact with contaminated water and soil. It is predominantly seen in places of tropical climate and in people who work in rice paddies fields. Although healthy people may get melioidosis, chronic medical conditions like diabetes, liver diseases, renal diseases, or immunocompromised patients have an increased risk of the disease.

How Are Glanders and Melioidosis Spread?

Glander is spread to humans when they come in contact with an infected animal's tissue or body fluids. It enters the body through cuts and wounds on the skin or the eyes, nose, and mouth.

Melioidosis is spread by direct contact with contaminated surfaces - contaminated soil and water, especially during the rainy season. It enters the body through inhalation of aerosols, ingesting contaminated substances, or abrasions on the skin.

What Are the Signs and Symptoms of Glanders and Melioidosis?

The symptoms of both glanders and melioidosis vary depending on the type of infection.

Localized Infection: When the bacteria enter the body through abrasions in the skin or the mucous membrane.

• Glanders: If the bacteria enter through abrasion on the skin, it may present as ulceration at the site, swollen lymph nodes, fever, muscle pain, and coughing. Other symptoms like eye tearing, light sensitivity, and diarrhea may also be seen. If the bacteria enter through the mucous membrane of the eyes, nose, and mouth, it will increase the mucous production in the site. Localized symptoms appear one to five days after the infection. If left untreated, it may spread to systemic or septicemic infections and occur one to four weeks after the infection.

• Melioidosis: Local infection often presents as ulcers, nodules, skin abscesses, pain, and swelling at the site of infection. Fever and muscle pain may also be seen. The other localized manifestations are headache, diarrhea, pus-filled skin lesions, muscle soreness, and confusion.

Pulmonary Infection: Pulmonary manifestations of glanders and melioidosis include bronchitis to severe pneumonia. Symptoms include fever, chest pain, cough, pulmonary abscess, headache, and pleural effusion.

In The Bloodstream: When a glanders infection spreads to the bloodstream, it is usually fatal within seven to ten days without treatment. The patient may have a fever, headache, respiratory distress, abdominal discomfort, joint pain, and disorientation in melioidosis.

The Mortality Rate of Melioidosis - bloodstream infection, can exceed 80%.

Chronic Infection: Chronic infection of both diseases may manifest as a re-activation of pneumonia or as multiple swellings or abscesses in the skin and muscles of the arm and leg or the spleen or liver. Glanders may present as small lumps, followed by ulcerations. Death may occur if left untreated for a few months.

Melioidosis may also spread to the bones, brain, lungs, and joints. Symptoms include fever, weight loss, chest pain, muscle and joint pain, stomachache, headaches, seizures, and central nervous system infections.

What Are the Complications of Glanders and Melioidosis?

Complications of glanders include multiple organ failure and death.

Complications of melioidosis include recurrent infection, organ failure, fluid build-up around the heart, and sepsis.

How Are Glanders and Melioidosis Diagnosed?

Both diseases can be diagnosed by culturing in a lab. Burkholderia pseudomallei can be diagnosed from the culturing of blood, sputum, and urine and a throat swab. Blood cultures are rarely positive when testing for Burkholderia mallei.

Indirect hemagglutination, direct immunofluorescence, and latex agglutination tests are done in some countries. In addition, computed tomography (CT) or ultrasound of the abdomen can help assess the abscesses of the liver, spleen, or prostate that may not present any clinical manifestations.

X-ray of the chest may show consolidations, cavitary lesions, effusions, and multiple lung abscesses and is performed routinely.

How Are Glanders and Melioidosis Treated?

Glanders is usually rare in humans; hence there are no evidence-based treatment guidelines for glanders. The treatment and management options are similar to that of melioidosis.

• Intravenous antibiotics initially for ten days to 14 days.

• Which is then switched to oral medication for 12 weeks to 20 weeks.

• To prevent relapse, it is necessary to continue the antibiotic treatment for several months.

• In case of severe conditions, they may require intensive care and hospitalization.

• Surgical drainage of abscesses.

How to Prevent Glanders and Melioidosis?

There is currently no vaccine for glanders and melioidosis; prevention would be to avoid the risk of exposure to the disease. Glanders can be prevented by identifying and eradicating infected animals and using appropriate personal protective equipment when dealing with potentially infected animals and in healthcare settings.

Melioidosis can be prevented by:

• People with an open wound or scar or having diabetes or chronic renal diseases should avoid touching the soil and standing water.

• Agricultural workers must wear protective boots while working to avoid infection on the feet and lower legs.

• Use of appropriate precaution guidelines when treating a patient with melioidosis.

Conclusion

Glanders and melioidosis are bacterial infections with similar symptoms and treatment options, caused by similar bacteria of the burkholderia species. Both diseases are considered bioweapon, as they are highly infectious, resistant to most antibiotics, and have a high mortality rate. Hence, it is vital to report any incident of infection immediately. However, it is possible to alleviate the disease with prompt treatment and management.