Melioidosis

Though Melioidosis has existed for more than 100 years, health officials and policy makers are paying attention only now. In 2015, Melioidosis killed 53% of infected people. This is almost equal to annual global mortality from Measles and greater than deaths from leptospirosis or dengue. Both measles and leptospirosis or dengue are rated as health priorities for many international health organizations. Furthermore, Melioidosis can become a potential agent for biological warfare and biological terrorism. Naturally Melioidosis is gaining priority attention.

What is Melioidosis?

Pathologist Alfred Whitmore and his assistant C.S. Krishnaswami first described Melioidosis in 1911 in Rangoon. Melioidosis is an infectious disease caused by bacteria. It is also known as Whitmore's disease. Melioidosis is caused by the bacteria Burkholderia Pseudomallei. This is a gram-negative bacterium mostly found in water, soil and on plants. Melioidosis affects humans and animals.

How do people get Melioidosis?

The infection is acquired when an individual comes in direct contact with contaminated soil and surface water. The modes of infection are ingestion, inhalation and inoculation (through local cuts and wounds on the skin). The latter appears to be most common. The disease does not spread from one person to another but may occur through contact with blood fluids of the infected person. Neonatal cases have been reported. It suggests either perinatal transmission or transplacental. Laboratory-acquired infections may rarely occur, especially if procedures produce aerosols.

Is Melioidosis region specific ?

Certain factors, environmental and climate support the microbe to thrive well when introduced. Till recently, the disease was considered to be restricted to Southeast Asia and Northern Australia. Philippines is considered to be endemic country of Melioidosis in Southeast Asia.

In United States, Melioidosis is reported to be rare. But Florida, Louisiana and Texas in United States and Okinawa and Kagoshima prefectures in Japan are rated as Melioidosis compatible based on climate and environmental factors. These regions have similar environmental factors like Caribbean islands and Taiwan. The microbe if introduced in these regions can thrive well.

What is the clear trend about Melioidosis ?

• Diabetic people are more susceptible to Melioidosis.
  
  
• No clear-cut gender bias observed so far.
  
  
• AIDS and intravenous drug users are more susceptible.
  
  
• Renal failure increases chances of Melioidosis.

What are the symptoms of Melioidosis ?

Symptoms are site-specific as symptoms vary depending on the site of infection. The infection can form a cavity of pus (abscess). The infection usually starts in the lung or in the skin and then spreads to other parts of the body. As it spreads Melioidosis can affect lungs, kidneys, liver, heart and circulatory system.

The pulmonary form of infection takes place when bacteria in aerosol form enters the respiratory tract. Symptoms of lung infection include shortness of breath, cough, chest pain, high fever, headache or anorexia and abnormal lung sounds.

Localized form of Melioidosis takes place when the bacteria enters the skin through a laceration or abrasion. This can lead to skin wounds with pain and swelling, fever, ulceration or abscess. There can be increased mucus production in the affected areas.

On entering the blood stream, symptoms differ. Associated symptoms include fever, headache, respiratory difficulties, abdominal pain or discomfort, joint pain, muscle tenderness etc. Disseminated infections of Melioidosis include fever, weight loss, stomach or chest pain, muscle or joint pain, headache and seizures.

When are Melioidosis symptoms noticeable ?

The incubation period of the bacterium is not clearly defined. The anticipation established is 1 to 21 days. On the other hand, there is a possibility of remaining asymptomatic from 10 days to many years after contracting the bacterium. But, when the symptoms begin, it can be sudden or gradual.

Being informed about Melioidosis is the key to seeking timely medical attention. Melioidosis can be fatal if not treated promptly. If you suspect Melioidosis infection, seek medical attention immediately.

How is Melioidosis diagnosed ?

Misdiagnosis can result in deaths. Distinguishing Melioidosis from pulmonary TB is challenging. The clinical manifestations are similar. Early diagnosis and effective treatment prevents casualties. Expert micro-biologists supervise Melioidosis diagnosis. Healthcare professionals recommend blood culture, skin-lesion sample, urine or sputum examination aided by microscopic evaluation in a laboratory.

Chances of infection are high if the blood test shows an elevated white blood cell count. In cases involving lung infection, chest x-ray is required to study presence of cavitating lesions resembling tuberculosis.

How is Melioidosis treated ?

Melioidosis is a treatable disease. Hospital admission is required only in severe cases. Treatment is entirely dependent on the location of Melioidosis. Treatment involves administering antibiotic therapy that includes intravenous microbial therapy for 10-14 days followed by oral antimicrobial therapy for 3-6 months. If required, surgical drainage of pus is beneficial.

Are there ways to prevent Melioidosis ?

Prevention through vaccination is not available currently. Preventive measures reduce risk of Melioidosis especially in areas where the risk of infection is high.

• Individuals with open wounds, diabetes and renal disease should avoid contact with soil and contaminated water.
  
• Workers in agricultural lands especially in endemic areas should wear boots to prevent infection through foot and legs.
  
• Health care workers should adhere to precautionary measures (protective rubber gloves, protective foot wear or waders) when attending to infected persons.