Researchers encounter rare chlorella infection

by Rob Payne
Symbiotic relationships: The protozoa, Paramecium bursaria (pictured) appears green due to several hundred symbiotic Chlorella dispersed throughout its cytoplasm. Credit: Proyecto Agua

A 30-year-old Western Australian man has become the second ever in the world to be diagnosed with a Chlorella wound infection.

The finding was published recently by researchers from PathWest Laboratory Medicine WA, Bunbury Regional Hospital and The University of Western Australia.

A unicellular algae of the family Chlorellacaea, Chlorella are found in fresh water, salt water and soil and have been known to infect sheep and cattle, generally through the intake of stagnant water contaminated with sewage or pastures irrigated with raw sewage.

The only previous case of in a human involved a 30-year-old woman in the United States who had a recent surgical wound infected after canoeing in a river in Nebraska.

Dr Julie Hart from PathWest says the WA patient presumably had Chlorella inoculate into a laceration on his knee which he received when jumping off his bicycle into a freshwater dam.

Initial treatment involved cleaning and suturing the wound, but two days later it had developed swelling, redness and a serious discharge.

This is consistent with Chlorella commonly inducing a strong granulomatous reaction, in which the immune system attempts to wall off substances perceived to be foreign but which it is unable to remove.

When the wound was opened up, doctors found a green-brown pus and evidence of necrotic fat.

They undertook a treatment of wound debridement and negative pressure and commenced the antibiotic ciprofloxacin when deep-tissue specimens grew Aeromonas hydrophilia, a heterotrophic Gram-negative bacterium.

Further incubation of specimens resulted in bright green colonies of unicellular organisms consistent with Chlorella.

Dr Hart says the infection is considered opportunistic.

This could be attributed to Chlorella's life cycle being characterised by endosporulation, a form of reproduction involving long periods of dormancy.

Still, the infection offers clinicians and the public a reminder to be aware.

"There are many bacteria in fresh water that could more commonly cause infection of a wound, for example, Aeromonas species, Pseudomonas species, Pleisiomonas species and Edwardsiella tarda," Dr Hart says.

"For clinicians, Chlorella should be considered in contaminated with fresh water from rivers and dams.

"Both human cases appear to have responded to surgical debridement and wound management, so these strategies should be the main focus of -contaminated wound management, to prevent and treat infections with unusual environmental organisms, such as Chlorella."

The patient saw his wound heal following three weeks of treatment, with no further complications noted.

More information: onlinelibrary.wiley.com/doi/10… 002/nmi2.50/abstract

add to favorites email to friend print save as pdf

Related Stories

Recommended for you

Second bird flu case confirmed in Canada

12 hours ago

The husband of a Canadian who was diagnosed earlier this week with bird flu after returning from a trip to China has also tested positive for the virus, health officials said Friday.

What exactly is coronavirus?

19 hours ago

The conflicts in Syria and Iraq are straining public health systems and public health efforts meant to prevent and detect the spread of infectious diseases. This is generating a "perfect storm" of conditions for outbreaks. Among the infections raising concern is Middle East Respiratory Syndrome, caused by a type of coronavirus, which emerged in 2012. ...

Scientists find Ebola virus is mutating

20 hours ago

(Medical Xpress)—Researchers working at Institut Pasteur in France have found that the Ebola virus is mutating "a lot" causing concern in the African countries where the virus has killed over eight thous ...

User comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.