A new thing for the media to fixate on…
The nation is heading toward the worst outbreak of West Nile disease in the 13 years that the virus has been on this continent, federal health authorities said Wednesday.
But it is still unclear where and how far cases will spread. Dallas declared an emergency last week, and West Nile deaths have been concentrated in Texas and a few nearby states, including Louisiana, Mississippi and Oklahoma, as well as South Dakota.
So far this year, there have been 1,118 cases and 41 deaths reported to the Centers for Disease Control and Prevention, Dr. Lyle R. Petersen, director of the agency’s division of vector-borne diseases, said Wednesday in a telephone news conference.
“That’s the highest number of cases ever reported to the C.D.C. by the third week of August,” he added. “And cases are trending upward.”
Only about one infection in 150 becomes serious enough for the patient to need hospitalization — usually when the virus gets into the brain and spinal cord. But 10 percent of those hospitalized die, and other patients are left paralyzed, comatose or with serious mental problems. A recent study by doctors in Houston found kidney disease high among survivors.
There is no vaccine, and no drug that specifically targets the virus, so health authorities advise people to avoid getting bitten.
(click here to continue reading West Nile Outbreak Shaping Up as Worst Ever in U.S., Authorities Say – NYTimes.com.)
The numbers may be small, but death is pretty serious, especially since there is no vaccine for West Nile. Illinois is gearing up as well:
The mosquito responsible for the West Nile virus flourished during the summer’s record heat and drought. Now, officials are concerned about emerging signs that a widespread outbreak may be on the horizon in Illinois.
Updated figures from the state Department of Public Health show extremely high numbers of the Culex pipiens species have tested positive for the disease — 71 percent in DuPage County and nearly 60 percent in Cook, the health department reported.
Although the 27 cases of West Nile virus in Illinois don’t represent a particularly high number, experts start to get anxious when just 10 percent of samples of virus-carrying mosquitoes test positive.
The reason, said Linn Haramis, program manager of vector control for the health department, is that history suggests that the 10 percent infection rate is a strong indicator the percentage is going to accelerate rapidly over the summer.
The rate of Culex pipiens mosquitoes statewide that had the West Nile virus stood at 25 percent Tuesday, Haramis said. Last year, that percentage was 8 percent, he added.
(click here to continue reading West Nile: Banner year for West Nile – chicagotribune.com.)
and it appears to be a mostly unremarked side effect of global planet change:
Mosquito activity is highly weather-sensitive. Cooler temperatures and heavy rain reduce the number of Culex pipiens, experts said. Downpours can wash away larvae growing in places such as catch basins and gutters. That didn’t happen this summer.
But high temperatures allowed the virus to replicate quicker, building to dangerous levels inside the mosquito, which infect people through its saliva, experts said.
Even the warmer winter may have helped. The mild weather then and in the early spring, combined with the hot summer, might have fostered conditions favorable to spread the virus, according to CDC officials.
“It’s a banner year for West Nile,” said Richard Pollack, a public health entomologist with the Harvard School of Public Health. “Not such a good year for people.”
Cases usually flare in the summer because the illness is most often transmitted from infected birds to people by mosquitoes.
Wear long sleeve clothing when walking in dusk and evening, avoid pools of standing water, and make sure your last will and testament is current. What more can you do?
More on the global change aspect from Scientific American:
According to the Centers for Disease Control, there have been over 1100 reported cases of West Nile virus disease in the US this year, including 42 deaths. If these numbers seem high, they are – in fact, it’s the highest number of reported cases since West Nile was first detected in the US in 1999, and West Nile season has just begun. Given that the peak of West Nile epidemics generally occurs in mid August, and it takes a few weeks for people to fall ill, the CDC expects that number to rise dramatically. But why now?
Though the CDC doesn’t have an official response to that question, the director of the CDC’s Vector-Borne Infectious Disease Division said that ‘unusually warm weather’ may be to blame. So far, 2012 is the hottest year on record in the United States according to the National Climatic Data Center, with record-breaking temperatures and drought a national norm. It’s likely no coincidence that some of the states hit hardest by West Nile are also feeling the brunt of the heat. More than half of cases have been reported from Texas alone, where the scorching heat has left only 12% of the state drought-free. Fifteen heat records were broken in Texas just last week on August 13th.
The heat waves, droughts and other weather events are the direct effects of climate change say leading scientists. As NASA researcher James Hansen explained in a recent Washington Post editorial, “our analysis shows that, for the extreme hot weather of the recent past, there is virtually no explanation other than climate change.” He says that the European heat wave of 2003, the Russian heat wave of 2010 and catastrophic droughts in Texas and Oklahoma last year are all the repercussions of climate change. Confidently, he adds that “once the data are gathered in a few weeks’ time, it’s likely that the same will be true for the extremely hot summer the United States is suffering through right now.”
The fact that the worst US West Nile epidemic in history happens to be occurring during what will likely prove to be the hottest summer on record doesn’t surprise epidemiologists. They have been predicting the effects of climate change on West Nile for over a decade. If they’re right, the US is only headed for worse epidemics.
While the CDC is hesitant to blame this year’s West Nile outbreak on climate change directly, the science is clear. Record-breaking incidences of West Nile are strongly linked to global climate patterns and the direct effects of carbon dioxide emissions. Climate change isn’t just going to screw with the environment, it will continue to have devastating public health implications. In addition to better mosquito control and virus surveillance, we need to focus our efforts on reducing and reversing climate change if we want to protect our health and our well-being.
(click here to continue reading Is Climate Change To Blame For This Year’s West Nile Outbreak? | Science Sushi, Scientific American Blog Network.)