World Bulletin / News Desk
Yosemite National Park has begun trapping and killing deer mice whose growing numbers may have helped create the conditions that led to a hantavirus outbreak that has infected eight park visitors, killing three, public health officials said on Tuesday.
Yosemite officials in recent weeks have warned some 22,000 people who stayed in the park in California over the summer that they may have been exposed to the rodent-borne lung disease, which kills over a third of those infected.
The U.S. Centers for Disease Control and Prevention has also sounded a worldwide alert, saying visitors to the park's popular Curry Village lodging area between June and August may be at risk. Park officials have closed nearly 100 tent cabins in Curry Village infested with deer mice, which carry the virus.
"From an ecological perspective, it appears that there was an unnaturally high population of rodents in the area. We are being proactive and reducing the population," Danielle Buttke, a veterinary epidemiologist for the National Park Service, told Reuters.
Buttke said the mice were being trapped in several areas of the park for monitoring purposes but believed they were being killed only in the Curry Village area, using snap traps.
Seven of the eight people confirmed to have been infected are believed to have contracted the virus in the village, while one stayed elsewhere in the park.
Public health officials trapped three times as many deer mice in the park's Tuolumne Meadows last week than were caught in a 2008 period, indicating that the deer mice population has grown, said Dr. Vicki Kramer, chief of vector-borne diseases at the state Public Health Department.
Dr. Charles Chiu, an infectious disease specialist at the University of California, San Francisco, said the growing deer mice population might help explain the outbreak.
"This could be an explanation for why we're seeing this particular cluster," Chiu said. "What you may have is the perfect storm of conditions: increasing prevalence of deer mice and campers with the same or common exposure to (lodging) infested with deer mice."
Officials are concerned that more Yosemite visitors could still fall ill because the virus can incubate for up to six weeks after exposure. There is no cure for the syndrome but early detection and hospital care increase survival rates.
The virus can lead to severe breathing difficulties and death. Early flu-like symptoms include headache, fever, muscle aches, shortness of breath and coughing.
Last month, authorities began trapping rodents in Yosemite to examine whether deer mice there were more likely to be infected with the hantavirus than deer mice elsewhere, Buttke said, but found they were not.
When authorities first identified the Yosemite hantavirus outbreak, rangers balked at the idea of trying to exterminate the deer mice, arguing that the mice play an important role in the Yosemite ecosystem.
But when they realized the deer mice population had swelled, they decided to thin it in an effort to rebalance the ecosystem, Buttke said. She theorized that weather combined with visitors bringing in food led to Yosemite's abundance of deer mice.
Deer mice release hantavirus in their urine and droppings. People can contract the virus when they breath contaminated air. Children rarely contract the virus, probably because it is often transmitted when adults sweep or vacuum droppings or cut and stack wood.
People usually contract the virus in small, confined spaces with poor ventilation. They also can become infected by eating contaminated food, touching tainted surfaces or being bitten by infected rodents.
The disease has killed 65 Californians and some 600 Americans since hantavirus was identified in 1993, but it has never been known to be transmitted between humans.
The business side of the new operating system was debuted Tuesday. In the spring, Microsoft will reveal consumer capabilities.
Atlas will give marketers access to Facebook's user data that they can use for specific ad campaigns.
The European Aviation Safety Agency allowed European airlines to permit the use of electronic devices throughout the whole flight
Water found in Earth's oceans, in meteorites and frozen in lunar craters predates the birth of the solar system, a study shows
The mission makes India the first country in Asia to reach Mars, after an attempt by regional rival China failed to leave earth's orbit in 2011.
Turkish-made electric car traveled 2,500 kilometers (about 1553 miles) to six cities and cost only 37.5 Turkish liras (about $17) since September 15.
Web users will face criminal action for spreading "false" information aimed at discrediting the government, the official KPL news agency said.
"All are welcome, regardless of religion, nationality or occupation, to contact our organization -- Mossad -- to work for us or to be involved in activities which could bring great personal benefit," reads the new "Contact us" section of the Mossad website
MAVEN will study how the solar wind strips away atoms and molecules in the planet's upper atmosphere, a process that scientists believe has been underway for eons.
Chief prosecutor Gholam-Hossein Mohseni-Ejei accused Communications Minister Mahmoud Vaezi of failing to unplug social networking sites and apps "with immoral and criminal content."
Promising 500km on just four hours' charge, the 'T-1', designed and produced by staff and pupils at Istanbul University arrives in eastern city of Erzurum during nationwide tour.
Blind people say the KNFB Reader app will enable a new level of engagement in everyday life, from reading menus in restaurants to browsing handouts in the classroom.
A successful Mars mission would boost the global standing of India's state-run space agency.
The Senate Armed Services Committee's year-long probe found the military's U.S. Transportation Command, or Transcom, was aware of only two out of at least 20 such cyber intrusions within a single year.
The new study revealed the role of hunter-gatherers from the Siberian region who the scientists called "ancient north Eurasians."
The iPad is expected to have a 9.7 inch screen, while the new version of the iPad mini will have a 7.9 inch screen, Bloomberg earlier reported