Not long ago, when infectious-disease specialist Connie Price saw a patient hospitalized with flu at Denver Health Medical Center, she had a powerful weapon at hand: a drug that could shorten the course of the illness and lessen its misery.
Now, the strength of that weapon, Tamiflu, has been undermined by a widely circulating flu strain, type A H1N1, that has developed the ability to resist the drug.
Even as this year's flu season winds down, doctors say the implications of the spread of drug-resistant flu strains could resonate in seasons to come, affecting treatment and highlighting the need for faster flu tests, new drugs and global monitoring of flu viruses.
TAMIFLU: Virus growing resistant to key weapon
Tamiflu, whose medical name is oseltamavir, is one of two drugs in a relatively new class of anti-flu medications that reduce the duration and severity of flu. Because it is easily taken in pill or liquid form, it quickly became the antiviral of choice for treating both seasonal flu and potential pandemic flu strains, such as H5N1, known as bird flu. Another drug in the same class is Relenza, or zanamavir, which has similar flu-fighting effects but is taken as an inhaled powder, which makes it difficult for some people to use, especially people who have lung problems such as asthma.
In recent years, because of rising concern about the potential for a flu pandemic, governments around the world have been stockpiling millions of doses of Tamiflu, along with smaller amounts of Relenza and older antivirals, amantadine and rimantadine.
Tamiflu still is effective against bird flu in most cases, though some variants show signs of reduced sensitivity, says Frederick Hayden of the Infectious Disease Society of America's Pandemic Flu Task Force. "It's important that we monitor susceptibility patterns, not only in humans but also in avian viruses."
Meanwhile, for doctors treating patients with regular flu, this season has been dizzyingly complicated. Type A H1N1 flu, the predominant strain circulating now, is the one resistant to Tamiflu; the two others in circulation, type A H3N2 and type B, are not.
Patients who have H1N1 flu can be treated with Relenza if they can inhale the medicine. If not, they can take amantadine or rimantadine. But if they have either of the other two flu strains, they can take only Tamiflu or Relenza, because H3N2 flu is resistant to amantadine and rimantadine, and those drugs don't work against type B flu.
The trouble is, most doctors don't know which flu strain is infecting their patients. The symptoms are the same. Rapid flu diagnostic tests may be able to tell if it's influenza A or B, but can't identify type A subtypes, such as H1N1 or H3N2. The gold-standard test, a viral culture, takes about a week to produce results.
Difficult choices
Price says that given the inability to quickly know exactly what flu strain is present, she issued a "blanket recommendation" for doctors treating patients with flu at her hospital. She advised them to use Relenza, if possible, and if not, to always combine Tamiflu with one of the older drugs, such as rimantadine.
That is "never desirable," she says, because it means some patients will be overmedicated and subject to drug side effects, such as nausea, loss of appetite, nervousness or dizziness.
The sickest patients who could benefit most from antiviral treatment, she says, are often those who are elderly or who have underlying health problems that put them at higher risk for flu complications. "Now, to give them two more drugs that may interact with other therapies, it makes it more complicated," to treat, Price says.
The U.S. Centers for Disease Control and Prevention says this has been a milder flu season than in previous years. But the most recent report shows flu is widespread in 30 states, and 32 children have died because of the flu since the season began last September. In the 2007-08 season, 88 children died of illnesses associated with flu.
Drugmakers are working on new antivirals, including a potent injectable that could be used for hospitalized patients. The drug, peramivir, developed by BioCryst with $102.6 million from the Department of Health and Human Services, "is a major public health priority," says Bill Sheridan, chief medical officer. Clinical trials are underway in Japan and the USA, but testing at least through next flu season is needed before the drug can be considered by the Food and Drug Administration.
Other medications are being developed, but they're not expected to be available for years, which leaves annual flu vaccination as the best defense, says Hayden, a flu researcher at the University of Virginia. "Make sure you get vaccinated," he says, "and use common sense in terms of reducing exposure to the virus."
http://www.usatoday.com/news/health/2009-03-22-flu-resistance_N.htm?loc=interstitialskip
ANCHORAGE, Alaska — Alaska's Mount Redoubt is rumbling again and geologists at the Alaska Volcano Observatory increased the official alert level to orange, the stage just before eruption.
A significant eruption did not appear imminent, geologists said Sunday, but they cautioned that conditions could evolve rapidly.
The 10,200-foot Redoubt Volcano is about 100 miles southwest of Anchorage.
Ash from the volcano could harm engines and is especially dangerous for aircraft. Ash blown to cities also can cause respiratory problems.
Residents of south-central Alaska have kept a close eye on Redoubt since the observatory on Jan. 25 warned that an eruption could occur at any moment. The alert level was downgraded last week after nearly two months.
Just after 1 p.m. Sunday, however, seismic activity picked up again.
"We got a return of this stuff we call volcanic tremors," said geologist Chris Waythomas. "Think of the phenomenon that produces sound in an organ pipe."
Instead of sound waves in a pipe, geologists detect movement of magma within cracks and fractures of the mountain that resonates and produces a distinct signal.
"We think it's associated with the hydrothermal system there. It's being reinvigorated," Waythomas said.
The tremors lasted about four hours and then settled down.
An observatory flight Sunday reported that a steam and ash plume rose as high as 15,000 feet (4,600 meters) above sea level and produced minor ash fall on the upper south flank of the mountain. Later reports indicated the plume had changed into mostly steam.
Ash emission had not been seen before, Waythomas said, and until samples are taken, geologists will not know whether it's new magma or, more likely, old ground-up material from previous episodes.
Other signs that a volcano could erupt are deformities in the landscape and the mix of gases escaping from vents on the side of the mountain.
Alaska volcanos typically explode and shoot ash upward, sometimes to 50,000 feet (15,000 meters), high into the jet stream. An eruption of Redoubt on Dec. 15, 1989, sent ash 150 miles (240 kilometers) away into the path of a KLM jet, stopping its engines. The jet dropped more than two miles (three kilometers) before the crew was able to restart engines and land safely at Anchorage.
http://frc4u.org/phpbb/index.php?topic=519.0
UK team builds robot fish to detect pollution
LONDON (Reuters) - Robot fish developed by British scientists are to be released into the sea off north Spain to detect pollution.
If next year's trial of the first five robotic fish in the northern Spanish port of Gijon is successful, the team hopes they will be used in rivers, lakes and seas across the world.
The carp-shaped robots, costing 20,000 pounds ($29,000) apiece, mimic the movement of real fish and are equipped with chemical sensors to sniff out potentially hazardous pollutants, such as leaks from vessels or underwater pipelines.
They will transmit the information back to shore using Wi-Fi technology.
Unlike earlier robotic fish, which needed remote controls, they will be able to navigate independently without any human interaction.
Rory Doyle, senior research scientist at engineering company BMT Group, which developed the robot fish with researchers at Essex University, said there were good reasons for making a fish-shaped robot, rather than a conventional mini-submarine.
"In using robotic fish we are building on a design created by hundreds of millions of years' worth of evolution which is incredibly energy efficient," he said.
"This efficiency is something we need to ensure that our pollution detection sensors can navigate in the underwater environment for hours on end."
The robot fish will be 1.5 meters (nearly 5 feet) long -- roughly the size of a seal.
http://www.reuters.com/article/technologyNews/idUSTRE52J1RY20090320
U.N. panel says world should ditch dollar
LUXEMBOURG (Reuters) - A U.N. panel will next week recommend that the world ditch the dollar as its reserve currency in favor of a shared basket of currencies, a member of the panel said on Wednesday, adding to pressure on the dollar.
Currency specialist Avinash Persaud, a member of the panel of experts, told a Reuters Funds Summit in Luxembourg that the proposal was to create something like the old Ecu, or European currency unit, that was a hard-traded, weighted basket.
Persaud, chairman of consultants Intelligence Capital and a former currency chief at JPMorgan, said the recommendation would be one of a number delivered to the United Nations on March 25 by the U.N. Commission of Experts on International Financial Reform.
"It is a good moment to move to a shared reserve currency," he said.
Central banks hold their reserves in a variety of currencies and gold, but the dollar has dominated as the most convincing store of value -- though its rate has wavered in recent years as the United States ran up huge twin budget and external deficits.
Some analysts said news of the U.N. panel's recommendation extended dollar losses because it fed into concerns about the future of the greenback as the main global reserve currency, raising the chances of central bank sales of dollar holdings.
"Speculation that major central banks would begin rebalancing their FX reserves has risen since the intensification of the dollar's slide between 2002 and mid-2008," CMC Markets said in a note.
Russia is also planning to propose the creation of a new reserve currency, to be issued by international financial institutions, at the April G20 meeting, according to the text of its proposals published on Monday.
It has significantly reduced the dollar's share in its own reserves in recent years.
GOOD TIME
Persaud said that the United States was concerned that holding the reserve currency made it impossible to run policy, while the rest of world was also unhappy with the generally declining dollar.
"There is a moment that can be grasped for change," he said.
"Today the Americans complain that when the world wants to save, it means a deficit. A shared (reserve) would reduce the possibility of global imbalances."
Persaud said the panel had been looking at using something like an expanded Special Drawing Right, originally created by the International Monetary Fund in 1969 but now used mainly as an accounting unit within similar organizations.
The SDR and the old Ecu are essentially combinations of currencies, weighted to a constituent's economic clout, which can be valued against other currencies and indeed against those inside the basket.
Persaud said there were two main reasons why policymakers might consider such a move, one being the current desire for a change from the dollar.
The other reason, he said, was the success of the euro, which incorporated a number of currencies but roughly speaking held on to the stability of the old German deutschemark compared with, say, the Greek drachma.
Persaud has long argued that the dollar would give way to the Chinese yuan as a global reserve currency within decades.
A shared reserve currency might negate this move, he said, but he believed that China would still like to take on the role.
http://www.reuters.com/article/newsOne/idUSTRE52H2CY20090318
China calls for new reserve currency
By Jamil Anderlini in Beijing
Published: March 23 2009 12:16 Last updated: March 24 2009 00:06
China’s central bank on Monday proposed replacing the US dollar as the international reserve currency with a new global system controlled by the International Monetary Fund.
In an essay posted on the People’s Bank of China’s website, Zhou Xiaochuan, the central bank’s governor, said the goal would be to create a reserve currency “that is disconnected from individual nations and is able to remain stable in the long run, thus removing the inherent deficiencies caused by using credit-based national currencies”.
Analysts said the proposal was an indication of Beijing’s fears that actions being taken to save the domestic US economy would have a negative impact on China.
“This is a clear sign that China, as the largest holder of US dollar financial assets, is concerned about the potential inflationary risk of the US Federal Reserve printing money,” said Qu Hongbin, chief China economist for HSBC.
Although Mr Zhou did not mention the US dollar, the essay gave a pointed critique of the current dollar-dominated monetary system.
“The outbreak of the [current] crisis and its spillover to the entire world reflected the inherent vulnerabilities and systemic risks in the existing international monetary system,” Mr Zhou wrote.
China has little choice but to hold the bulk of its $2,000bn of foreign exchange reserves in US dollars, and this is unlikely to change in the near future.
To replace the current system, Mr Zhou suggested expanding the role of special drawing rights, which were introduced by the IMF in 1969 to support the Bretton Woods fixed exchange rate regime but became less relevant once that collapsed in the 1970s.
Today, the value of SDRs is based on a basket of four currencies – the US dollar, yen, euro and sterling – and they are used largely as a unit of account by the IMF and some other international organisations.
China’s proposal would expand the basket of currencies forming the basis of SDR valuation to all major economies and set up a settlement system between SDRs and other currencies so they could be used in international trade and financial transactions.
Countries would entrust a portion of their SDR reserves to the IMF to manage collectively on their behalf and SDRs would gradually replace existing reserve currencies.
Mr Zhou said the proposal would require “extraordinary political vision and courage” and acknowledged a debt to John Maynard Keynes, who made a similar suggestion in the 1940s.
http://www.ft.com/cms/s/0/7851925a-17a2-11de-8c9d-0000779fd2ac.html
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