What is Glanders and Melioidosis?
Glanders and Melioidosis are both infectious diseases caused by specific bacteria. Glanders is caused by a type of bacteria called Burkholderia mallei, while Melioidosis is caused by another bacteria known as Burkholderia pseudomallei. Both types of bacteria can cause illness in animals and humans.
The bacteria causing Glanders and Melioidosis are very similar to each other. Glanders was traditionally a common disease in horses, donkeys, and mules. On the other hand, Melioidosis was first identified in 38 patients in Rangoon, Burma, by a scientist named Alfred Whitmore in 1912.
What Causes Glanders and Melioidosis?
Glanders is a rare disease seen in humans that usually affects animals like horses, donkeys, and mules. People who are in close contact with these infected animals may become sick. The bacteria can get into the body through the eyes, nose, mouth or any cuts and scrapes in the skin. The bacteria responsible for this disease, known as Burkholderia mallei, is a kind of bacteria that specifically affects mammals and needs to cause the disease in order to spread from one host to another.
Another disease similar to glanders, called Melioidosis, could show up in a short span of one day to three weeks, which is referred to as the acute form. However, sometimes, you might be carrying this disease for years without showing any symptoms, which is known as latent Melioidosis.
Melioidosis is often seen in individuals who have other health conditions, such as diabetes, kidney disease, abuse alcohol, and thalassemia (a blood disorder), but even healthy people can contract this disease. The bacteria that cause Melioidosis, known as Burkholderia pseudomallei, are found in soil and water. People usually get this disease from being exposed to mud or standing water.
Risk Factors and Frequency for Glanders and Melioidosis
Glanders disease has been eradicated in the United States, however, it still exists in Africa, Asia, the Middle East, Central America, and South America. Melioidosis, another similar disease, is commonly found in southeast Asia and northern Australia, but it has also been reported in South America, Central America, Africa, and the Middle East.
In 2016, studies projected that there would be roughly 165,000 new melioidosis cases globally. These findings also suggested that the disease is not reported enough. One crucial factor contributing to this illness is its presence in soil and water, which means weather events such as floods and typhoons can trigger outbreaks of melioidosis.
Unfortunately, there is no available vaccine for either of these diseases. For glanders, humans can contract it by coming into contact with infected animals, even if the animals do not show any apparent symptoms. You can get glanders if you touch your mucous membranes, inhale it, or if it comes in contact with open wounds on your skin. Finally, it’s rare, but both glanders and melioidosis can be passed from person to person.
Signs and Symptoms of Glanders and Melioidosis
Glanders and melioidosis are two diseases with different incubation periods and symptoms. Glanders can incubate in the body for anywhere from 1 to 21 days, and in rare cases, even months or years. The first sign of glanders is usually a fever, which then progresses to pneumonia, pustules, and abscesses. The acute version of this disease often results in death within 7 to 10 days of the first symptoms showing up. Chronic glanders can also occur, leading to death within a few months. Survivors of chronic glanders remain carriers of the disease.
On the other hand, the incubation period of melioidosis can be incredibly variable, ranging from just 2 days to several years. Acute melioidosis symptoms include:
- Fever
- Cough
- Pleurisy
- Arthralgia
- Myalgia
- Headache
- Loss of appetite
- Night sweats
Melioidosis can present in many ways, from acute or chronic localized infections to sepsis. Abscesses (collections of pus) in the liver, spleen, prostate, and parotid glands are common. It is possible for infections in the abdomen to occur without any obvious pain. The abscesses often appear in a ‘honeycomb’ pattern on CT scans. Chronic melioidosis is considered when symptoms continue for longer than 2 months and occurs in roughly 10% of patients.
Testing for Glanders and Melioidosis
Glanders and melioidosis are diseases that can be identified in a lab. The bacteria that causes these diseases, called Burkholderia pseudomallei, can be detected with a blood test, a spit test, a urine test, or a throat swab. But in glanders, caused specifically by Burkholderia mallei, blood tests don’t usually show the bacteria. It’s important to note that running these tests should be done with high safety measures (known as BSL-3 precautions). Some countries also offer other tests, like indirect hemagglutination, latex agglutination, and direct immunofluorescence tests.
Melioidosis can’t be confirmed with imaging tests like X-rays or scans. But doctors still recommend a CT scan or ultrasound of your belly to look for signs of infection, like abscesses (pockets of infection) in your liver, spleen or prostate that might not show symptoms. In addition, a chest X-ray is often done. This can help determine if the infection has spread to your lungs, causing issues like consolidations (parts of the lung filled with fluid), cavitary lesions (holes in the lung tissues), effusions (extra fluid around the lungs), empyemas (pus in the lung area), or multiple lung abscesses.
Treatment Options for Glanders and Melioidosis
If a patient is severely affected with lung complications, their condition might worsen and lead to breathing failure, where they would require a machine to help them breathe. They might also face blood-related complications or body-wide infection, known as sepsis and coagulopathy respectively. In one case, the treatment for glanders, a bacterial infection, using certain types of antibiotics was successful in a lab worker who became infected. A CT scan after the treatment showed improvements in the condition of the individual’s spleen and liver.
Without treatment, glanders can be fatal in 95% of the cases, leading to death within 7 to 10 days after symptoms appear. Even with treatment, the mortality rate is quite high, around 50%. The septicemic form of melioidosis, another bacterial infection, has a mortality rate exceeding 90%. However, if the infection is not complicated and is managed early with appropriate antibiotics, the mortality rate may go as low as 10%.
Surgeries are recommended for the treatment of abscesses, pockets of pus, formed in the prostate gland or in and around the joints due to melioidosis. However, surgeries are generally not recommended for abscesses in the liver and spleen. The treatment for acute melioidosis primarily involves the use of certain strong antibiotics. In the acute phase of the disease, patients are treated with such antibiotics through an IV, for at least 2 weeks. This is followed by a 20-week course of other types of antibiotics to completely get rid of the disease. Abscesses in most organ systems often resolve after antibiotic therapy but abscesses in the prostate usually require surgical removal.
In instances of critically ill patients with melioidosis, a treatment involving certain antibiotics and a compound to stimulate white blood cell production has been found to significantly reduce mortality in Australia. However, it’s worth noting that up to 20% of patients may experience a recurrence of melioidosis, but odds can be reduced to as little as 4% with a specific antibiotic therapy.
Given the risks associated with these diseases, lifelong follow-up is recommended. Currently, there are no vaccines available for glanders or melioidosis. Similarly, there are no approved preventative antibiotic treatments for these diseases. However, one study has shown that using a specific antibiotic as a pre-exposure or post-exposure prophylaxis (preventive treatment) within 24 hours of exposure to the bacteria Burkholderia pseudomallei resulted in a 100% survival rate in mice.
What else can Glanders and Melioidosis be?
These are some infectious diseases that may need to be considered for diagnosis:
- Anthrax
- Bacterial pneumonia
- Plague (CBRNE)
- Smallpox (CBRNE)
- Malaria
- Mycoplasmal pneumonia
- Typhoid fever
- Viral pneumonia
What to expect with Glanders and Melioidosis
The death rate for the skin form of systemic and untreated glanders, a rare infectious disease, is quite high, ranging from 90% to 95%. However, with appropriate treatment, this rate is significantly reduced to 50%.
Possible Complications When Diagnosed with Glanders and Melioidosis
Septic shock, abscesses in the liver, spleen, and prostate, and potentially even death are some of the severe ramifications that may occur.
- Septic shock
- Abscesses in the liver
- Abscesses in the spleen
- Abscesses in the prostate
- Potential death
