Study sheds new light on river blindness parasite

Jan 12, 2011

The team found that a bacterium inside the worm acts as a 'disguise' for the parasite, resulting in the immune system reacting to it in an ineffective way. The bacteria protect the worm from the body's natural defences, but once the bacteria are removed with antibiotics, the immune system responds appropriately, releasing cells, called eosinophils, that kill the worm.

Antibiotics are successful against the parasite, but the long treatment regime means that it has limited use across whole communities. These new findings suggest that if medics could prime the to recognise the worm, a shorter duration of antibiotic treatment may be sufficient to overcome its bacterial defences.

River Blindness is caused by black flies that breed in rivers and deposit the of a worm into the person they bite. The infection leads to severe itching of the skin and lesions of the eye which can result in blindness. It affects millions of people in developing countries, particularly in West and Central Africa. A closely related parasite also infects cattle, which causes lumps to appear on the animal's skin but does not cause blindness or other illness.

Dr Ben Makepeace, from the University's Institute of Infection and Global Health, explains: "Our team has already shown that removing the with results in the death of the worm, but until now we were unaware of how the bacteria protected the parasite in the first instance. Antibiotics can rid the parasite of the bacteria, allowing the immune system to respond properly, but it is a long treatment process, lasting up to six weeks.

"Now we can begin to look for a way to 'prime' the body into reacting to the parasite more efficiently. Currently there is no vaccine for , but if a candidate could be identified this may help boost the immune system ahead of antibiotic treatment and reduce the length of time patients have to take the drug. It is essential that whole communities are cured of the infection and the more we know about the mechanisms the parasite uses to survive in the body, the further we can progress with finding a practical treatment that kills adults worms and not just the larval stages."

Explore further: Blocking a fork in the road to DNA replication

More information: The research is published in Proceedings of the Royal Society B.

add to favorites email to friend print save as pdf

Related Stories

New drug resistance found in river blindness

Jun 15, 2007

A 20-year effort to control the spread of onchocerciasis, or river blindness, in African communities is threatened by the development of drug resistance in the parasite that causes the disease, a study by McGill University ...

How the parasitic worm has turned

Jun 14, 2010

(PhysOrg.com) -- Parasites in the gut such as whipworm have an essential role in developing a healthy immune system, University of Manchester scientists have found.

The onchocerciasis parasite showing signs of resistance

Jan 31, 2008

Onchocerciasis is an infection caused by Onchocerca volvulus, a parasite nematode worm transmitted to humans by a species of black fly of the Simulium genus whose larvae develop in fast-flowing rivers. Infected subjects suffer ...

Recommended for you

Researchers capture picture of microRNA in action

19 hours ago

Biologists at The Scripps Research Institute (TSRI) have described the atomic-level workings of "microRNA" molecules, which control the expression of genes in all animals and plants.

Blocking a fork in the road to DNA replication

21 hours ago

A team of Whitehead Institute scientists has discovered the surprising manner in which an enigmatic protein known as SUUR acts to control gene copy number during DNA replication. It's a finding that could shed new light on ...

Cell division, minus the cells

23 hours ago

(Phys.org) —The process of cell division is central to life. The last stage, when two daughter cells split from each other, has fascinated scientists since the dawn of cell biology in the Victorian era. ...

A new method simplifies the analysis of RNA structure

Oct 30, 2014

To understand the function of an RNA molecule, similar to the better-known DNA and vital for cell metabolism, we need to know its three-dimensional structure. Unfortunately, establishing the shape of an RNA ...

User comments : 0

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.