Melioidosis: Thailand’s unknown deadly disease

Ubon Ratchathani, Thailand –  By the time Bunsri Mamak, 50, arrived at Sappasit Prasong Hospital in Ubon Ratchathani city in Thailand’s northeast, he was delirious and a very sick man. He had spent several weeks visiting local clinics and hospitals trying to find out what was wrong with him when he first developed the symptoms – high fever and pain in his legs. The doctors he visited failed to diagnose his illness and provide the necessary treatment.

Ultimately, the district hospital advised him to visit the provincial hospital in the city, where he finally received a diagnosis – just in time to save his life.

He had spent 13 days in intensive care receiving intravenous antibiotics to treat the sepsis, the infection that had begun spreading through his blood. Afterwards, he was sent home to rest and complete a 20-week course of oral antibiotics.

Mamak was diagnosed with melioidosis, the little-known disease that is Thailand’s third most deadly infectious disease, after AIDS and tuberculosis. He was lucky to be alive.

A deadly disease

The United States Center for Disease Control and Prevention classifies  melioidosis as a microorganism that could be used as a “bioterrorism agent”, placing it in the same category as anthrax. Although it has never been used in bioterrorism, this classification gives insight into its dangers to humans.

Endemic to Thailand’s northeast, melioidosis is caused by a soil and water-dwelling bacteria, B pseudomallei, which is found around the world in tropical regions from East Asia to sub-Saharan Africa, as well as Latin America and the Middle East.

Every year, in the agriculturally intensive regions of Thailand, there are thousands of cases of melioidosis. Of those infected, approximately 40 percent die from the disease, even if they begin treatment. If the patient is not diagnosed and provided with effective antibiotics on time, the mortality rate is at a much higher 90 percent. 

Quick diagnosis increases the chances of survival, but it is the difficulty in diagnosing it that causes so many problems, as symptoms vary largely from patient to patient. 

The disease was first identified in 1911 in Yangon, but later gained attention, particularly from American doctors during the Vietnam War, when many wounded soldiers were infected through contact with the soil and water. The Americans had  dubbed  the disease the ‘Vietnam Time Bomb’ because exposed soldiers often didn’t develop symptoms until after they had arrived back home. 

Mamak was lucky to be living near Ubon Ratchathani, which has a specialised laboratory and melioidosis clinic and the 1,000-bed Sappasit Prasong Provincial Hospital with doctors well-attuned to spotting the disease.

Known as the Mahidol Oxford Tropical Medicine Research Unit (MORU), the lab was established through a long-time collaboration between Bangkok’s Mahidol University and the United Kingdom’s Oxford University and is funded by the Welcome Trust, which has been developing treatments and researching tropical infectious diseases since 1979. The research centre in Sappasit Prasong Hospital is at the forefront of field research into melioidosis.

Identifying and treating melioidosis

Dr Vipada Chaowagul is known as the “Mother of Melioidosis” among her colleagues. She has worked in the field for almost 40 years. 

Although she is the deputy director of administration at another hospital in the city, she comes to Sappasit Prasong Hospital every Tuesday. The province has such a high number of cases that the hospital started a special weekly melioidosis clinic for patients to receive test results and check-ups.

By lunchtime, she has seen almost 30 patients. Between her visits, she tells of the challenges she has faced in her career of treating the disease. While the lab became proficient at diagnosing the disease, effective treatment techniques took longer to develop. 

“For five years, I had been working on melioidosis and was finding that most of the serious cases die because conventional treatment was not working,” Dr Chaowagul tells Al Jazeera, adding that 95 percent of her patients were dying.

“The cases would come in on one day, and we would know the result of the culture after they were already dead. Because they came and died in 24 hours.” 

A chance meeting with British doctor Nick White of Oxford University during a medical conference in a neighbouring province changed everything. She told him about the disease and that conventional treatments weren’t working. She also shared her desire to start a comparative study with a new antibiotic that had been shown to be successful.

Dr White offered to help and wrote a proposal to receive funding and samples of the antibiotic, and with this, Dr Chaowagul was able to start her research. The results were staggering, and the research halved the fatalities.

MORU, the melioidosis research laboratory, was set up at Sappasit Prasong Hospital not long after. It is now a leading unit worldwide in clinical melioidosis research holding the largest collection of bacterial isolates linked to a patient database in the world. 

But as diagnosis and treatment techniques improved, the number of cases identified has increased.

Northeast Thailand now has more than 2,500 culture-confirmed cases of melioidosis per year. The  40 percent mortality figure makes the disease comparable to the number of Tuberculosis deaths and is much higher than those of malaria or dengue fever.

A personal battle

Gumphol Wongsuvan, 40, has worked in the research laboratories of MORU since graduating with a degree in public health from Mahidol University in Bangkok 13 years ago.

He sees a lot of cases of melioidosis, but in May 2016, the disease would come calling much closer to home. One day while at work, Wongsuvan received a call from his wife. His father, who had been diagnosed with leukaemia earlier that year, was running a very high fever. Wongsuvan immediately drove home and brought his father back to the hospital. 

Because of his quick reaction and knowledge of the disease, within 7 hours of the onset of the fever, his father was on a course of antibiotics treatment for melioidosis, although the family was baffled as to how the already-sick man had contracted the disease.

“There was one time when he went into the fields. He didn’t go to work but just went for a walk. Simply that,” says Wongsuvan.

Research conducted by MORU has shown that one of the reasons why melioidosis is so prolific in this province is because of the sheer concentration of that particular bacteria in the soil – on average, 10,000 bacterial cells that cause melioidosis are present in a gramme of soil.

Without the quick diagnosis, he believes his father would have died considering his body was already frail from the other illness.

Misdiagnosis and death

Misdiagnosis remains one of the biggest challenges facing those who are infected by the bacteria. Dr Direk Limmathurotsakul, the head of microbiology department at MORU Faculty of Tropical Medicine in Bangkok has been battling for 15 years to educate others about the incidence and mortality of melioidosis. He has been working for years to collect data and accurate figures on the disease.

Figures from research at Sappasit Prasong Hospital show that, in 2015, of the 378 melioidosis cases, 134 resulted in death.

“Most of them die without knowing that they die of melioidosis. They die quickly,” Dr Limmathurotsakul says. 

But terrifyingly, he adds, many patients who were suspected of contracting melioidosis were immediately administered antibiotics, even before laboratory confirmation. Yet, they still died.

Official figures show very different numbers, however. In 2013, 2014 and 2015, the hospital figures revealed over 100 deaths per year, but government figures put the number of deaths at four, 11 and five, respectively.

The difference may seem shocking, but it is explained by data collection and records keeping methodologies. The Thai Ministry of Public Health simply records what is reported on a notifiable disease form submitted by the hospitals.

“It has been found that fatal cases of melioidosis usually died very quickly, within one to three days following hospital admission, while it typically takes four to seven days for bacterial culture results to become available,” explains Dr Limmathurotsakul.

“This resulted in fatal cases of melioidosis not being reported by surveillance officers as part of the disease surveillance system maintained by the Ministry of Public Health.”

This contributes to the problem, says Dr Limmathurotsakul, because it misrepresents the scale of the problem on an institutional level.

“It is, therefore, important to educate and remind laboratory staff, clinicians, statisticians and epidemiologists to comply with the requirements of the existing surveillance system by including in their report every single case of melioidosis with B pseudomallei-positive cultures.”

This initiative is being implemented by the collaboration between Thailand Melioidosis Network and the health ministry, according to Dr Limmathurotsakul.

The understated numbers show the discrepancy in treatment available in the country and represent a dangerous cycle of inaccuracy that leads to a further lack of awareness.

“When public awareness is zero, do you think any doctor will write on the death certificate that you die of this disease?” asks  Dr Limmathurotsakul.

The tragedy is amplified, says Dr Limmathurotsakul, because local people could easily protect themselves by simply boiling water before drinking it and wearing rubber boots when they work in the fields, where most people still work bare-footed.

In a January 2016 report published in Nature magazine, a team of experts from around the world, including Dr Limmathurotsakul, collated global information about the disease.

The report estimates that melioidosis is severely underreported in the 45 countries in which it is known to be endemic. Furthermore, the report showed melioidosis is likely endemic in a further 34 countries that have never reported the disease. Using the data, they predicted that up to 165,000 cases could occur each year, with approximately 89,000 fatalities. 

There is an urgency to implement prevention campaigns and raise awareness, says Dr Limmathurotsakul.

“A vaccine could take 10 years to come and may not even come at all for 20 to 30 years. But should we wait and let 90,000 die each year while we wait?

“To me, that seems unfair and difficult for me to accept. What we can do now we should do. We must give education, give them boots to wear and teach them to drink clean water.”

For the last five years, Dr Limmathurotsakul and his team have been working alongside the health ministry in collecting data and addressing these issues.

“From the start, we have been doing it with [the ministry’s] system and trying very hard to identify what are the problems in their system and put the right data into their system rather than totally re-invent the wheel and just [say], ‘This is the right data, believe us,'” he explains.

At the end of this year, the public health ministry plans to release a report with an accurate data of deaths caused by melioidosis in Thailand. Everyone involved hopes that this report will reveal the true danger of this little-known disease, and the wheel of change will start turning.