Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Newly discovered virus implicated in deadly Chinese outbreaks

23.03.2011
Tick-borne disease identified as emerging threat

Five years ago, large numbers of farmers in central China began falling victim to an mysterious disease marked by high fever, gastrointestinal disorder and an appalling mortality rate — as high as 30 percent in initial reports.

Investigators from the Chinese Center for Disease Control and Prevention hurried to the scene of the outbreak. On the basis of DNA evidence, they quickly concluded that it had been caused by human granulocytic anaplasmosis, a bacteria transmitted by tick bites.

Now, though, subsequent studies have shown that original conclusion was incorrect, and that a previously unknown and dangerous virus has been responsible for seasonal outbreaks of the disease in six of China's most populated provinces.

"We expected to find a bacterial infection behaving in an unexpected way — human anaplasmosis has a less than one percent fatality rate in the U.S., and it rarely causes abdominal pain or vomiting or diarrhea," said Dr. Xue-Jie Yu of the University of Texas Medical Branch at Galveston, lead author of a paper on the discovery now appearing in the "online advance" section of the New England Journal of Medicine. "Instead, we found an unknown virus."

Researchers have dubbed the newly discovered pathogen Severe Fever with Thrombocytopenia Syndrome virus, and placed it in the Bunyaviridae family, along with the hantaviruses and Rift Valley Fever virus. Later investigation has placed its mortality rate at 12 percent, still alarmingly high.

Yu, a specialist in tick-borne bacteria like the species responsible for HGA, first suspected that a virus might be responsible for the outbreaks after close examination of patients' clinical data showed big differences from symptoms produced by HGA, and blood sera drawn from patients revealed no HGA or HGA antibodies.

Yu became certain that a virus was at fault after sera taken from patients retained its ability to kill cells, despite being passed through a filter that blocked all bacteria. Still, initial genetic tests failed to generate a match with a known pathogen.

"Clearly, we had a virus, but what virus?" Yu said. "I told the people I was working with that they needed to be even more careful, because we were working with an unknown."

That caution seemed appropriate when electron microscope studies of deactivated virus particles revealed what appeared to be a hantavirus — associated in Asia with hemorrhagic fever and in the Americas with a deadly pulmonary syndrome. But when Yu and his colleagues managed to extract the virus' entire genetic code, they found that it didn't match any other known virus.

When researchers from the Chinese Center for Disease Control and Prevention led by study author Dr. Yu Wang analyzed sera taken from 241 symptomatic patients from Henan, Hubei, Shandong, Anhui, Jiangsu and Liaoning provinces, they found 171 contained either the previously unknown virus itself or antibodies against it. In addition, the scientists found the virus in 10 out of 186 ticks collected from farm animals in the area where the patients lived.

"This seems to be a tick-borne disease, and the disease comes out when the ticks come out, from late March to late July," Yu said. "Fortunately, even though the full life cycle is not clear, we know that for the virus humans are a dead end — we don't have human-to-human transmission as we did with SARS."

Other authors of the New England Journal of Medicine paper include UTMB Health visiting scientist Dr. Yan Liu, professor Vsevolod Popov, professor Dr. David Walker and research associate Dr. Lihong Zhang; Dr. Qun Li, Wen-Wu Yin, Hang Zhou and Dr. Zi-Jian Feng of the Chinese Center for Disease Control and Prevention; Dr. Mi-Fang Liang, Jian-Dong Li, Dr. Yu-Lan Sun, Quan-Fu Zhang, Chuan Li, Dr. Yan-Ping Zhang, Wei Wu, Qin Wang, Shi-Wen Wang, Jing-Dong Song, Tao Wan, Li-Na Sun, Dr. Tao Hong and Dr. De-Xin Li of the State Key Laboratory for Molecular Virology and Genetic Engineering, National Institute for Viral Disease Control and Prevention; Shou-Yin Zhang, Dr. Rong Hai, Biao Kan, Kang-Lin Wan, Dr. Huai-Qi Jing, Dr. Jin-Xin Lu, Jin-Rong He, Jing-Shang Zhang and Xiu-Ping Fu of the State Key Laboratory for Infectious Disease Control and Prevention, National Institute for Communicable Disease Control and Prevention; Fa-Xian Zhan, Xu-Hua Guan and Dr. Jia-Fa Liu of the Hubei Province CDC; Dr. Xian-Jun Wang and Zhen-Qiang Bi of the Shandong Province CDC; Dr. Guo-Hua Liu of the Henan Province CDC; Dr. Jun Ren of the Anhui Province CDC; Dr. Hua Wang of the Jiangsu Province CDC; Dr. Zhuo Zhao of the Liaoning Province CDC; and Dr. Yu Zhang of the Hubei Province Department of Health.

The China Mega-Project for Infectious Diseases, the Western Regional Center of Excellence for Biodefense and Emerging Infectious Diseases and the Chinese Recruitment Program of Global Experts provided support for this research.

ABOUT UTMB Health: Established in 1891, Texas' first academic health center comprises four health sciences schools, three institutes for advanced study, a research enterprise that includes one of only two national laboratories dedicated to the safe study of infectious threats to human health, and a health system offering a full range of primary and specialized medical services throughout Galveston County and the Texas Gulf Coast region. UTMB Health is a component of the University of Texas System.

The University of Texas Medical Branch at Galveston
Public Affairs Office
301 University Boulevard, Suite 3.102
Galveston, Texas 77555-0144

Jim Kelly | EurekAlert!
Further information:
http://www.utmb.edu

More articles from Life Sciences:

nachricht Cells communicate in a dynamic code
19.02.2018 | California Institute of Technology

nachricht Studying mitosis' structure to understand the inside of cancer cells
19.02.2018 | Biophysical Society

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: In best circles: First integrated circuit from self-assembled polymer

For the first time, a team of researchers at the Max-Planck Institute (MPI) for Polymer Research in Mainz, Germany, has succeeded in making an integrated circuit (IC) from just a monolayer of a semiconducting polymer via a bottom-up, self-assembly approach.

In the self-assembly process, the semiconducting polymer arranges itself into an ordered monolayer in a transistor. The transistors are binary switches used...

Im Focus: Demonstration of a single molecule piezoelectric effect

Breakthrough provides a new concept of the design of molecular motors, sensors and electricity generators at nanoscale

Researchers from the Institute of Organic Chemistry and Biochemistry of the CAS (IOCB Prague), Institute of Physics of the CAS (IP CAS) and Palacký University...

Im Focus: Hybrid optics bring color imaging using ultrathin metalenses into focus

For photographers and scientists, lenses are lifesavers. They reflect and refract light, making possible the imaging systems that drive discovery through the microscope and preserve history through cameras.

But today's glass-based lenses are bulky and resist miniaturization. Next-generation technologies, such as ultrathin cameras or tiny microscopes, require...

Im Focus: Stem cell divisions in the adult brain seen for the first time

Scientists from the University of Zurich have succeeded for the first time in tracking individual stem cells and their neuronal progeny over months within the intact adult brain. This study sheds light on how new neurons are produced throughout life.

The generation of new nerve cells was once thought to taper off at the end of embryonic development. However, recent research has shown that the adult brain...

Im Focus: Interference as a new method for cooling quantum devices

Theoretical physicists propose to use negative interference to control heat flow in quantum devices. Study published in Physical Review Letters

Quantum computer parts are sensitive and need to be cooled to very low temperatures. Their tiny size makes them particularly susceptible to a temperature...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

2nd International Conference on High Temperature Shape Memory Alloys (HTSMAs)

15.02.2018 | Event News

Aachen DC Grid Summit 2018

13.02.2018 | Event News

How Global Climate Policy Can Learn from the Energy Transition

12.02.2018 | Event News

 
Latest News

Contacting the molecular world through graphene nanoribbons

19.02.2018 | Materials Sciences

When Proteins Shake Hands

19.02.2018 | Materials Sciences

Cells communicate in a dynamic code

19.02.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>