News / Health

Scientists Try New Tactic Against Schistosomiasis

The re-introduction of indigenous prawns into this enclosed area in Lampsar village, in northern Senegal is reducing the rate of schistosomiasis infections. (VOA/J. Lazuta)
The re-introduction of indigenous prawns into this enclosed area in Lampsar village, in northern Senegal is reducing the rate of schistosomiasis infections. (VOA/J. Lazuta)
Jennifer Lazuta
Every year, more than 240 million people get a potentially deadly parasitic infection known as schistosomiasis, transmitted by fresh water snails.  Infection rates have risen to as high as 80 percent in some parts of Africa, where communities often rely on rivers and lakes for bathing, cooking and other household chores. In Saint-Louis, Senegal, aid workers are using another indigenous species, the prawn, to keep parasite levels in check in local rivers.

In mid-morning, Coumba Ngiané washes a bucketful of family dishes and clothes.
 
She says the tap water is often cut off in the village, and so the women must come to the river to do laundry and bathe. She says when it gets hot, the children come here to cool off and play. People get sick, she says, and they know it is from the water but they can’t stay away.  

Freshwater snails are the host for the microscopic parasite that gives you schistosomiasis.  That parasite gets in the water and the larvae can enter your body through a cut, or even just the pores of your skin.

The larvae then lay eggs in the body, leading to diarrhea, abdominal pain and fever.  It infects the intestines and if left untreated, can lead to organ failure and even death.  In children, it can stunt growth and brain development.

There is treatment, but that won’t stop you from being re-infected the next time you enter the water.

The disease isn’t new to the Saint-Louis region of Senegal.  But it got worse after the government built a dam on the Senegal River in 1986 to stop salt water from flowing onto farmers’ fields.  The indigenous prawns that eat the snails that carry the parasite were nearly wiped out.

Amit Savaia, an Israeli prawn specialist currently working in the Saint-Louis area, said the prawns need to move from fresh water to salt water in order to breed.

“The dam that was built prevented them from migrating," said Savaia who is from Ben Gurion University. "So upstream [from] the dam, the prawns were almost sure extinct.  And if the prawns are extinct, the snails have a very comfortable habitat to bloom and grow, and spread [schistosomiasis].”

Savaia says in some villages the rate of infection rose from less than 10 percent to more than 80 percent.

Now, “Projet Crevette,” or the “Prawn Project,” is trying to change that.

Every three months, the project releases between 50 and 100 prawns into enclosures at seven test sites in the area.

Project officer Nicolas Jouanard says the idea is to restore balance to the ecosystem.

“The idea with the prawns is that when they arrive they eat the snails that are in place and that are infected," said Jouanard. "You will get new snails because the prawns are not able to eat every snail, but the snails that you will have here will be small snails, a new generation of snails.  So for them it will take time to be infected again.  When they are young and small they cannot be infected.”

Scientists say dam construction has disrupted river ecosystems and increased schistosomiasis infection rates in several parts of the world, including China, Egypt and Ivory Coast, in recent decades.

The founder of the prawn project in Senegal, Elizabeth Huttinger, says their experiment with prawns is a first and the results of the 12-month testing phase are “very promising.”
 
“On the snail info, the very exciting thing is that there are no infected snails there anymore," said Huttinger. "But what is particularly interesting, is that the intensity of the infections at the prawn site are about 15 times lower than what they are at the control site.”
 
That means 15 times fewer people are getting sick in the areas where prawns have been re-introduced.  And chronic infections are 40 times lower, as compared to the areas with no shrimp.

Because the dam is still in place, to keep the project going, researchers are teaching villagers at the test sites how to raise and breed prawns in plastic barrels full of fresh water and salt water.  The villagers can then keep transferring prawns to the river to keep infection rates down.

Huttinger said they hope to replicate the project in other villages and, ultimately, apply the model worldwide.

You May Like

Lion Cecil's Killing Sparks 'Canned Hunting' Debate in S. Africa

Conservationists believe incident, which triggered worldwide outrage, will reshape debate about practice in which hunters are allowed to target animals bred for hunting More

US Urges Taliban to Stay With Afghan Peace Talks

Top US Afghan diplomat also meets with Pakistani, Afghan officials following news of Mullah Omar's death More

Environmentalists Issue Warning on Mekong Biodiversity

Scientists say decades of economic development, hydropower-dam construction, lax law enforcement and trafficking have taken their toll More

This forum has been closed.
Comment Sorting
Comments
     
by: Swambe Akim from: Dakar, Senegal
April 22, 2013 5:29 PM
God bless you beautiful angles of the House of Israel. in Africa we dance and cry in your honor. Thank you

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
Astronauts Train Underwater for Deep Space Missionsi
|| 0:00:00
...    
🔇
X
George Putic
July 30, 2015 8:59 PM
Manned deep space missions are still a long way off, but space agencies are already testing procedures, equipment and human stamina for operations in extreme environment conditions. Small groups of astronauts take turns in spending days in an underwater lab, off Florida’s southern coast, simulating future missions to some remote world. VOA’s George Putic reports.
Video

Video Astronauts Train Underwater for Deep Space Missions

Manned deep space missions are still a long way off, but space agencies are already testing procedures, equipment and human stamina for operations in extreme environment conditions. Small groups of astronauts take turns in spending days in an underwater lab, off Florida’s southern coast, simulating future missions to some remote world. VOA’s George Putic reports.
Video

Video Civil Rights Leaders Struggled to Achieve Voting Rights Act

Fifty years ago, lawmakers approved, and U.S. President Lyndon Johnson signed, the Voting Rights Act of 1965. The measure outlawed racial discrimination in voting, giving millions of blacks in many parts of the southern United States federal enforcement of the right to vote. Correspondent Chris Simkins introduces us to some civil rights leaders who were on the front lines in the struggle for voting rights.
Video

Video Booming London Property a ‘Haven for Dirty Money’

Billions of dollars of so-called ‘dirty money’ from the proceeds of crime - especially from Russia - are being laundered through the London property market, according to anti-corruption activists. As Henry Ridgwell reports from the British capital, the government has pledged to crack down on the practice.
Video

Video Hometown of Boy Scouts of America Founder Reacts to Gay Leader Decision

Ottawa, Illinois, is the hometown of W.D. Boyce, who founded the Boy Scouts of America in 1910. In Ottawa, where Scouting remains an important part of the legacy of the community, the end of the organization's ban on openly gay adult leaders was seen as inevitable. VOA's Kane Farabaugh reports.
Video

Video 'Metal Muscles' Flex a New Bionic Hand

Artificial limbs, including the most complex of them – the human hand – are getting more life-like and useful due to constant advances in tiny hydraulic, pneumatic and electric motors called actuators. But now, as VOA’s George Putic reports, scientists in Germany say the future of the prosthetic hand may lie not in motors but in wires that can ‘remember’ their shape.
Video

Video Russia Accused of Abusing Interpol to Pursue Opponents

A British pro-democracy group has accused Russia of abusing the global law enforcement agency Interpol by requesting the arrest and extradition of political opponents. A new report by the group notes such requests can mean the accused are unable to travel and are often unable to open bank accounts. VOA's Henry Ridgwell reports.
Video

Video 'Positive Atmosphere' Points Toward TPP Trade Deal in Hawaii

Talks on a major new trade agreement among 12 Pacific Rim nations are said to be nearing completion in Hawaii. Some trade experts say the "positive atmosphere" at the discussions could mean a deal is within reach, but there is still hard bargaining to be done over many issues and products, including U.S. drugs and Japanese rice. VOA's Jim Randle reports.
Video

Video Genome Initiative Urgently Moves to Freeze DNA Before Species Go Extinct

Earth is in the midst of its sixth mass extinction. The last such event was caused by an asteroid 66 million years ago. It killed off the dinosaurs and practically everything else. So scientists are in a race against time to classify the estimated 11 million species alive today. So far only 2 million are described by science, and researchers are worried many will disappear before they even have a name. VOA’s Rosanne Skirble reports.
Video

Video Scientists: One-Dose Malaria Cure is Possible

Scientists have long been trying to develop an effective protection and cure for malaria - one of the deadliest diseases that affects people in tropical areas, especially children. As the World Health Organization announces plans to begin clinical trials of a promising new vaccine, scientists in South Africa report that they too are at an important threshold. George Putic reports, they are testing a compound that could be a single-dose cure for malaria.
Video

Video 'New York' Magazine Features 35 Cosby Accusers

The latest issue of 'New York' magazine features 35 women who say they were drugged and raped by film and television celebrity Bill Cosby. The women are aged from 44 to 80 and come from different walks of life and races. The magazine interviewed each of them separately, but Zlatica Hoke reports their stories are similar.
Video

Video US Calls Fight Against Human Trafficking a Must Win

The United States is promising not to give up its fight against what Secretary of State John Kerry calls the “scourge” of modern slavery. Officials released the country’s annual human trafficking report Monday – a report that’s being met with some criticism. VOA’s National Security correspondent Jeff Seldin has more from the State Department.
Video

Video Washington DC Underground Streetcar Station to Become Arts Venue

Abandoned more than 50 years ago, the underground streetcar station in Washington D.C.’s historic DuPont Circle district is about to be reborn. The plan calls for turning the spacious underground platforms - once meant to be a transportation hub, - into a unique space for art exhibitions, presentations, concerts and even a film set. Roman Mamonov has more from beneath the streets of the U.S. capital. Joy Wagner narrates his report.
Video

Video Europe’s Twin Crises Collide in Greece as Migrant Numbers Soar

Greece has replaced Italy as the main gateway for migrants into Europe, with more than 100,000 arrivals in the first six months of 2015. Many want to move further into Europe and escape Greece’s economic crisis, but they face widespread dangers on the journey overland through the Balkans. VOA's Henry Ridgwell reports.
Video

Video Stink Intensifies as Lebanon’s Trash Crisis Continues

After the closure of a major rubbish dump a week ago, the streets of Beirut are filling up with trash. Having failed to draw up a plan B, politicians are struggling to deal with the problem. John Owens has more for VOA from Beirut.
Video

Video Paris Rolls Out Blueprint to Fight Climate Change

A U.N. climate conference in December aims to produce an ambitious agreement to fight heat-trapping greenhouse gases. But many local governments are not waiting, and have drafted their own climate action plans. That’s the case with Paris — which is getting special attention, since it’s hosting the climate summit. Lisa Bryant takes a look for VOA at the transformation of the French capital into an eco-city.

VOA Blogs