Glanders is an infectious disease that is caused by the bacterium Burkholderia mallei. While people can get the disease, glanders is primarily a disease affecting horses. It also affects donkeys and mules and can be naturally contracted by other mammals such as goats, dogs, and cats. It is also called as Farcey.
Glanders is caused by the bacterium Burkholderia mallei which is also known as Pseudomonas mallei. The bacteria can be found only in the infected susceptible host and it cannot be found in the water, soil and plants. Normally humans acquires glanders from equids via direct contact with the broken skin or mucous membranes. The bacteria can also be transmitted through the intact skin. The secondary mode of transmission is through the droplets from the infected equid or patients.
Once in the host synthesis and release of certain toxins can occur. The amount of the toxins released is insignificant and no clinical disease process is ensured. The symptoms depends upon the amount o the toxins released by the organisms. The toxin released by the bacteria is called as pyocyanin a blue green pigment that interferes with the terminal electron transfer system, lecithinase which might result in the cell lysis by degrading lecithin in certain cell membranes, collagenase, lipase and hemolysin. Melioidosis is an infectious disease caused by B. pseudomallei ( Formerly P pseudomallei). The organism is widely present in the soil and water of the tropical region. It is spread to the humans via direct contact with the contaminated source, mainly during the rainy seasons. The disease more commonly occurs in the person who has other comorbidities such as diabetes, hypertension, alcoholism , immunosuppression and renal failure.
B.pseudomalle is considered as a biological weapon which can be used in the bioweapons. It is highly potentially to become bacteremic thereby increasing the chances of morbidity and mortality rates. The incubation period in naturally acquired infections can vary from days to months to years. The incubation period after an aerosol attack is expected to be from 10-14 days. Glanders is similar to the melioidosis such that the both produces the similar infections.
Bacteria enter the skin through a laceration or abrasion or by breakage in mucous membrane, and a local infection with ulceration develops. The incubation period is 1-5 days. Swollen lymph glands may develop. Bacteria that enter the host through mucous membranes can cause increased mucus production in the affected areas.
When bacteria are aerosolized and enter the respiratory tract via inhalation or hematogenous spread, pulmonary infections may develop. Pneumonia, pulmonary abscesses, and pleural effusions can occur. The incubation period is 10-14 days. With inhalational melioidosis, cutaneous abscesses may develop and take months to appear.
When bacteria is transmitted in the bloodstream in glanders, it is usually fatal within 7-10 days. The septicemia that develops affects multiple systems, and cutaneous, hepatic, and splenic involvement may or may not occur. With melioidosis, bacteremia is observed with chronically ill patients (eg, patients with HIV, patients with diabetes). They develop respiratory distress, headaches, fever, diarrhea, pus-filled lesions on the skin, and abscesses throughout the body. Septicemia may be overwhelming, with a 90% fatality rate and death occurring within 24-48 hours.
Chronic form
The chronic form involves multiple abscesses, which may affect the liver, spleen, skin, or muscles. This form is also known as farcy in glanders disease. Melioidosis, in addition to this chronic form, can become reactive many years after the primary infection.
The most common source of infection is ingestion of contaminated food or water. Contaminated aerosols (produced by coughing and sneezing), and contaminated fomites brought to the animals via grooming equipment and tack may also be a source of infection.
The bacteria can also enter the body through contact with lesions or abrasions of the skin or through mucosa. In this case, a local infection with ulceration may develop spreading to other parts of the body in the course of the disease.
Poor husbandry and feeding conditions as well as animal transport can be predisposing factors. Unsanitary conditions and over-crowded stables are risk factors.
Difficulty in breathing
Wheezing cough
Sneezing
Rapid breathing
Difficulty in speech
Pressure on the chest
Swollen lymph nodes
Microbiology:
The gram stain reveals small , gram negative bacilli, which might show irregular pattern with the methylene blue stains or wright stains.
They tends to show safety pin appearance. The organisms can be cultured from the abscess, secretions, sputum, blood and urine with the standard culture media. Primary isolation of the virus requires 48 to 73 hours.
The ash downs stain medium also provides correct evaluation of the bacterium and it is considered as the selective medium.
Blood culture often shows positive results. And the presence of positive urine culture shows prostatitis or renal abscesses. In septicemia blood culture results might be negative just before death.
Meat nutrient agar or the addition of 1-5% of glucose may accelerate growth of the bacteria.
PCR aid in the detection of the bacterial DNA.
Chest Xray:
The chest x ray predicts any abnormal area in the lungs
Computed tomography:
It reveals the slice of the lung. It uses both the combination of x ray and computer aided device.
It helps to analyse the size, shape and position of any lung tumour and also it helps in the detection of enlarged lymph nodes.
It also looks for any masses in the adrenal gland, liver, brain and other organs.
CT guided needle Biopsy:
CT scan might be used to guide a biopsy needle into this area to get the tissue for lung cancer.
MRI scan:
It uses the soft tissue image of the organ. It uses the both the magnet and radiowaves.
It often reveals whether the cancer cells has spread to the brain or spinal cord.
Serologic test:
Serologic agglutination test can be used to view the hemagglutination test.
A four fold increase in the titre suggest the disease
The mortality rate is 90-95% when it involves the lung and if it is untreated and 45% when it is treated.
Washing hands carefully with soap and water after contact with the blister-like lesions, after handling nose and throat discharges, and after contact with faeces such as with toileting and nappy changing.
Using separate eating and drinking utensils.
Avoid sharing items of personal hygiene (e.g. towels, washers and toothbrushes) and clothing (particularly shoes and socks).
Thoroughly wash and clean any soiled clothing and surfaces or toys that may have been contaminated.
Teach children about cough and sneeze etiquette, immediate disposal of tissues, and to wash hands afterwards.
