News / Science & Technology

Gene Studies of Ebola in Sierra Leone Show Virus Mutating Fast

Reuters

Genetic studies of some of the earliest Ebola cases in Sierra Leone reveal more than 300 genetic changes in the virus as it leapt from person to person, changes that could blunt the effectiveness of diagnostic tests and experimental treatments now in development, researchers said on Thursday.

“We found the virus is doing what viruses do. It's mutating,” said Pardis Sabeti of Harvard University and the Broad Institute, who led the massive study of samples from 78 people in Sierra Leone, all of whose infections could be traced to a faith healer whose claims of a cure attracted Ebola patients from Guinea, where the virus first took hold.

The findings, published in Science, suggest the virus is mutating quickly and in ways that could affect current diagnostics and future vaccines and treatments, such as GlaxoSmithKline's Ebola vaccine, which was just fast-tracked to begin clinical trials, or the antibody drug ZMapp, being developed by California biotech Mapp Biopharmaceutical.

The findings come as the World Health Organization said that the epidemic could infect more than 20,000 people and spread to more countries. A WHO representative could not immediately be reached for comment on the latest genetic study.

Study coauthor Robert Garry of Tulane University said the virus is mutating at twice the rate in people as it was in animal hosts, such as fruit bats.

Garry said the study has shown changes in the glycoprotein, the surface protein that binds the virus to human cells, allowing it to start replicating in its human host. “It's also what your immune system will recognize,” he said.

In an unusual step, the researchers posted the sequences online as soon as they became available, giving other researchers early access to the data.

Erica Ollmann Saphire of the Scripps Research Institute in La Jolla, California, has already checked the data to see if it impacts the three antibodies in ZMapp, a drug in short supply that has been tried on several individuals, including the two U.S. missionaries who contracted Ebola in Sierra Leone and who have since recovered.

“It appears that they do not [affect ZMapp],” said Saphire, who directs a consortium to develop antibody treatments for Ebola and related viruses. But she said the data “will be critical to seeing if any of the other antibodies in our pool could be affected.”

Saphire said the speed with which Sabeti and colleagues mapped genetic changes in the virus gives researchers information that “will also be critical” to companies developing RNA-based therapeutics.

That could impact treatments under way from Vancouver-based Tekmira Pharmaceuticals and privately-held Profectus BioSciences of Tarrytown, New York.

Part of what makes the data useful is the precise picture it paints as the epidemic unfolded. Sabeti credits years of work by her lab, colleagues at Tulane and the Sierra Leone Ministry of Health and Sanitation in developing a response network for Lassa fever, a virus similar to Ebola that is endemic in West Africa.

Several of the study authors gave their lives to the work, including Dr. Sheik Humarr Khan, the beloved “hero” doctor from the Kenema Government Hospital, who died from Ebola.

The team had been doing surveillance for two months when the first case of Ebola arrived from Guinea on May 25. That case involved a “sowei” or tribal healer, whose claim of a cure lured sick Ebola victims from nearby Guinea.

“When she contracted Ebola and died, there were a lot of people who came to her funeral,” Garry said. One of these was a young pregnant woman who became infected and traveled to Kenema Government Hospital, where she was diagnosed with Ebola.

With the Lassa surveillance team in place, they quickly began testing samples.

“We've been able to capture the initial spread from that one person and to follow all of these contacts and everything with sequencing,” Garry said.

The team used a technique called deep sequencing in which sequences are done repeatedly to generate highly specific results, allowing them to see not only how the virus is mutating from person to person, but how it is mutating in cells within the same person.

What is not clear from the study is whether the mutations are fueling the epidemic by allowing the virus to grow better in people and become easier to spread. That will require further tests in the lab, Garry said.

You May Like

Brutality Eroding IS Financial Support

Director of National Intelligence James Clapper says IS's penchant for publicizing beheadings, other brutal forms of punishment hurts group’s bottom line More

Studies: Climate Change a Factor in Disasters in Syria, California

The studies point to the possibility of clear and present dangers from a threat often considered to be far in the future More

Video Afghan Refugees Complain of Harassment in Pakistan

Afghan officials and human rights organizations assert that Pakistani authorities are using deadly attack at school in Peshawar as pretext to push out Afghan refugees More

Featured Videos

Your JavaScript is turned off or you have an old version of Adobe's Flash Player. Get the latest Flash player.
Kerry Seeks Assurances of Russian Non-Interference in Ukrainei
X
March 03, 2015 3:11 AM
U.S. Secretary of State John Kerry has told his Russian counterpart, Sergei Lavrov, that his country could face further consequences to what he called its “already strained economy” if Moscow does not fully comply with a cease-fire in Ukraine. The two met, on Monday, on the sidelines of a U.N. Human Rights Council meeting in Geneva, where Kerry outlined human rights violations in Russian-annexed Crimea and eastern Ukraine. VOA State Department correspondent Pam Dockins reports from Geneva.
Video

Video Kerry Seeks Assurances of Russian Non-Interference in Ukraine

U.S. Secretary of State John Kerry has told his Russian counterpart, Sergei Lavrov, that his country could face further consequences to what he called its “already strained economy” if Moscow does not fully comply with a cease-fire in Ukraine. The two met, on Monday, on the sidelines of a U.N. Human Rights Council meeting in Geneva, where Kerry outlined human rights violations in Russian-annexed Crimea and eastern Ukraine. VOA State Department correspondent Pam Dockins reports from Geneva.
Video

Video Smartphones May Help in Diagnosing HIV

Diagnosing infections such as HIV requires expensive clinical tests, making the procedure too costly for many poor patients or those living in remote areas. But a new technology called lab-on-a-chip may make the tests more accessible to many. VOA’s George Putic reports.
Video

Video Afghan Refugees Complain of Harassment in Pakistan

Afghan officials have expressed concern over reports of a crackdown on Afghan refugees in Pakistan following the Peshawar school attack in December. Reports of mass arrests and police harassment coupled with fear of an uncertain future are making life difficult for a population that fled its homeland to escape war. VOA’s Ayesha Tanzeem reports from Islamabad.
Video

Video Ukrainian Volunteers Prepare to Defend Mariupol

Despite the ongoing ceasefire in Ukraine, soldiers in the city of Mariupol fear that pro-Russian separatists may be getting ready to attack. The separatists must take or encircle the city if they wish to gain land access to Crimea, which was annexed by Russia early last year. But Ukrainian forces, many of them volunteers, say they are determined to defend it. Patrick Wells reports from Mariupol.
Video

Video Moscow Restaurants Suffer in Bad Economy, Look for Opportunity

As low oil prices and Western sanctions force Russia's economy into recession, thousands of Moscow restaurants are expected to close their doors. Restaurant owners face rents tied to foreign currency, while rising food prices mean Russians are spending less when they dine out. One entrepreneur in Moscow has started a dinner kit delivery service for those who want to cook at home to save money but not skimp on quality. VOA's Daniel Schearf reports.
Video

Video US, Cuba Report Progress in Latest Talks to Restore Ties

The United States and Cuba say they have made progress in the second round of talks on restoring diplomatic relations more than 50 years after breaking off ties. Delegations from both sides met in Washington on Friday to work on opening embassies in Havana and Washington and iron out key obstacles to historic change. VOA’s Mary Alice Salinas reports from the State Department.
Video

Video Presidential Hopefuls Battle for Conservative Hearts and Minds

One after another, presumptive Republican presidential contenders auditioned for conservative support this week at the Conservative Political Action Conference held outside Washington. The rhetoric was tough as a large field of potential candidates tried to woo conservative support with red-meat attacks on President Barack Obama and Democrats in Congress. VOA Political Columnist Jim Malone takes a look.
Video

Video NYC's Restaurant Week: An Economic Boom in Fine Dining

New Yorkers take pride in setting world trends — in fashion, the arts and fine dining. The city’s famous biannual Restaurant Week plays a significant role in a booming tourism industry that sustains 359,000 jobs and generates $61 billion in yearly revenue. VOA's Ramon Taylor reports.
Video

Video Brookhaven at Cutting Edge of US Energy Research

Issues like the Keystone XL pipeline, fracking and instability in the Middle East are driving debate in the U.S. about making America energy independent. Recently, the American Energy Innovation Council urged Congress and the White House to make expanded energy research a priority. One beneficiary of increased energy spending would be the Brookhaven National Lab, where clean, renewable, efficient energy is the goal. VOA's Bernard Shusman reports.
Video

Video Southern US Cities Preserve Civil Rights Heritage to Boost Tourism

There has been a surge of interest in the American civil rights movement of the 1950s and '60s, thanks in part to the Hollywood motion picture "Selma." Five decades later, communities in the South are embracing the dark chapters of their past with hopes of luring tourism dollars. VOA's Chris Simkins reports.
Video

Video Deep Under Antarctic Ice Sheet, Life!

With the end of summer in the Southern hemisphere, the Antarctic research season is over. Scientists from Northern Illinois University are back in their laboratory after a 3-month expedition on the Ross Ice Shelf, the world’s largest floating ice sheet. As VOA’s Rosanne Skirble reports, they hope to find clues to explain the dynamics of the rapidly melting ice and its impact on sea level rise.
Video

Video Lao Dam Project Runs Into Opposition

A Lao dam project on a section of the Mekong River is drawing opposition from local fishermen, international environmental groups and neighboring countries. VOA's Say Mony visited the region to investigate the concerns. Colin Lovett narrates.

All About America

Circumventing Censorship

An Internet Primer for Healthy Web Habits

As surveillance and censoring technologies advance, so, too, do new tools for your computer or mobile device that help protect your privacy and break through Internet censorship.
More