Guyana: a new infectious bacterium discovered

Guyana: a new infectious bacterium discovered

Sparouine’s anaplasmosis was diagnosed in a man 18 months after his infection. This is the only identified case of this animal-to-human transmitted disease to date.

Fever, muscle pain, headache, nosebleeds and severe anemia. Here are the symptoms suffered by a man in his 60s in a remote area of ​​Guyana. The amateur gold digger was infected with a previously unknown bacterium: anaplasmosis from Sparouine.

His diagnosis, however, is due to chance. The man had taken part in a campaign to study malaria in 2019. On that occasion, he had taken a blood sample that scientists were able to obtain when he fell ill. It was the team led by Olivier Duron, director of research at the CNRS in Montpellier on microbes in ticks, that worked on this case.

“Working with the Cayenne Hospital Center and the Pasteur Institute in Guyana sparked our interest in the samples they collected for malaria surveillance. We looked for any microbes they might have in those blood samples. And so we discovered a sample that was positive for a new bacterium,” explains the research leader.

Eighteen months after this first sample, the symptoms appeared. “The man must have had symptoms before, but since he lives in an area prone to malaria, that shouldn’t have alarmed him,” Olivier Duron suspects. In the hospital it is impossible to know what the amateur gold digger is suffering from. He is eventually released from the facility three weeks later after undergoing drug treatment.

Sparouine’s anaplasmosis was diagnosed two months after he was discharged from the hospital. The new bacterium, which comes from the Anaplasma family, inherited the name of the creek where the gold panner lived, the Sparouine creek.

Sparouine’s anamplasmosis is not transmitted from person to person. To become contaminated, a man must have had contact with a tick that carries the bacterium. The gold miner, who lived in a remote region of Guyana, had a greater chance of becoming infected. “This person, if they had been a city dweller, would not have been exposed to ticks. Ticks that fed on wild animals,” recalls Olivier Duron.

The first infected patient already had comorbidities. “This patient had his spleen removed. The spleen is an important organ because it filters red blood cells. A lack of it makes the patient more susceptible to such bacterial infections.”

To date, the sixty-year-old is the only case discovered. “Hospitals only test known diseases. And since there’s no test to detect this bacterium, we don’t know. (…) We must carry out “diagnostic tests” to find out if there are other cases in Guyana,” explains the CNRS researcher.

But in general, Sparouine’s anaplasmosis is not the only unknown infectious bacterium in Guyana. “Every day at the Cayenne hospital center you have a proportion of patients with infections that we have not identified,” recalls Olivier Duron.

The Montpellier CNRS is working closely with the Cayenne Hospital Center and the Guyana Pasteur Institute to identify bacteria of this genus. “Every year we go to Guyana to take samples.”

Anaplasma family bacteria have been found on sloths and cats in Brazil by other researchers.