"The only things we have to go by are the actual health data," said James Tamerius, a postdoctoral researcher in environmental health sciences at the Mailman School of Public Health at Columbia University. Based on this information, he noted, some patterns have started to emerge.

Tamerius explained that heavy fall and winter precipitation preceded previous spikes in valley fever by a year or so. He also noted that the disease tends to cluster near swaths of desert. "These big, open environments are what's necessary," he said. Cases also emerge as the dust is perturbed, often on construction sites and sometimes from dust storms that occasionally blanket the region.

As for the climate, Tamerius said it is hard to tell if warming temperatures are having an effect on the increases in the disease. "Some people think it has to do with changes in climate. Some people think it has to do with people moving in from out of state," he said, noting that previously unexposed people, like retirees settling down in Phoenix, may be at greater risk. The Centers for Disease Control and Prevention notes on its valley fever website that 30 to 60 percent of people who live in endemic regions are exposed to the fungi at some point in their lives. Better surveillance, awareness and reporting may also be pushing numbers higher.

Researchers are concerned because there is no reliable way to anticipate a surge or outbreak, or even increased risk for the disease. "There's not enough ecological data at the sub-meter scale to make those predictions," Tabor said. Valley fever's regional impacts also make it harder for local officials to garner national attention and research support.

For now, health officials are pinning their hopes on a vaccine to push back against dust clouds of infection. "This is a disease that's very hard to prevent because you can't tell people not to breathe," Tsang said.

Reprinted from Climatewire with permission from Environment & Energy Publishing, LLC. www.eenews.net, 202-628-6500

5 Comments

1. 1. donnawanna 03:46 PM 9/14/12

   Animals are affected too.

   Reply | Report Abuse | Link to this

2. 2. ErnestPayne 09:01 PM 9/14/12

   Without a national health care system the disease could be far more dangerous and under recorded.

   Reply | Report Abuse | Link to this

3. 3. Sisko 12:20 PM 9/17/12

   LOL--Climatewire promotes ever more mindless propaganda.

   Reply | Report Abuse | Link to this

4. 4. marjorum 02:47 AM 9/19/12

   Every summer Phoenix has haboobs--gigantic dust storms thousands of feet high and dozens of miles wide that roll out of the desert from the south. I have lived in the area since 1990 and cannot remember ever experiencing more than 5 per year. But not this year! So far in 2012, there have 30 or more (not sure of exact number, since I stopped counting at 22); in one 24-hour period, there were two of them. Last year the count was up, but nothing like this year. The Health Department was expecting an increase in Valley Fever cases; their expectations have been realized, and the haboob season is still ongoing.

   Reply | Report Abuse | Link to this

5. 5. marjorum in reply to ErnestPayne 03:13 AM 9/19/12

   ALL persons living in the desert southwest are presumed to be exposed, yet 60% of those, as evidenced by antibody titers, never become ill or experience only a mild respiratory-type sickness. It is transmitted by inhalation of spore-containing dust; it is not transmissable person-to-person.

   Reply | Report Abuse | Link to this