Heartland-virus

Coronavirus particles with their characteristic spiky halos.

Virus R Us

Initially, the recent death of a Saudi Arabian man from an unidentified viral infection renewed fears of another SARS panic, which swept around the world in 2003, infecting more than 8,000 people and killing almost 1,000.

It turns out, however, that while the mysterious virus superficially resembled SARS, it was in fact more closely related to coronaviruses that infect Southeast Asia bats. Coronaviruses get their name from their characteristic halo of projecting membrane proteins.

The identification, reported by Dutch virologists who managed to sequence the entire viral genome of 30,118 letters in less than a month, is reassuring in some ways: The virus doesn’t appear to be particularly virulent and hasn’t yet acquired the ability to jump from human to human. Researchers suspect the Saudi Arabian man was infected via an “amplifier” animal, such as a civet cat. When a virus jumps species, it typically doesn’t travel directly from originating host to humans. Amplifier animals get their name because they serve as intermediary steps, providing a place for viruses to replicate and increase in numbers, boosting their infectiousness.

On the other hand, the new viral threat is one of several recent reminders that the world is full of ever-changing potential microbial dangers. In Missouri, for example, researchers recently identified a new “Heartland virus.” In Central Africa, a new form of hemorrhagic fever has been discovered.

In the latter case, the term “new” is relative.  The virus was only recently reported in PloS Pathogens, but the three cases described are three years old. (Tissues samples from the patients – two of whom died – had languished in a freezer in Kinshasa, Zaire until a smart doctor realized what they were.)

Unusual Tick-Borne Virus Lurks In Missouri’s Woods

Last year, scientists got the chance to solve a medical mystery — well, at least half of it. This week the final puzzle pieces fell into place, as investigators tracked the newly identified virus to an eight-legged bug.

The mystery actually began with two Missouri farmers who came down with a strange illness in 2009. They had high fevers, diarrhea and nausea. Their platelet counts dropped dramatically, though they didn’t experience any abnormal bleeding.

Doctors thought it was a bacterial infection. But antibiotics didn’t help. So a quick-thinking physician at Heartland Regional Medical Center in St. Joseph, Mo., sent the men’s blood to the Centers for Disease Control and Prevention.

When virologists looked at the samples under the microscope, they discovered a virus that no one had ever seen before. They named it the Heartland virus, in honor of its origin and the Midwest.

Both farmers eventually recovered from the illness. But a piece of the puzzle was still missing. How did the men catch the virus? Where did it come from?

Now entomologists at the CDC have filled in the blanks. The bug specialists have identified the Heartland virus in ticks at a farm and in a park in northwest Missouri, near where the two farmers live.

“It’s the first time anyone has found it in the wild, in the environment,” says the study’s lead author, Harry Savage. “It means the virus is yet another tick-borne disease in the U.S. — and another reason to prevent getting bit.”

Both farmers had been bitten by ticks before getting sick. So Savage and his colleagues hunted for the virus in 12 locations around St. Joseph and the Missouri River. They collected more than 50,000 ticks during the summer of 2012, and even picked the bloodsuckers off horses and dogs on the patients’ farms.

The virus showed up in only one species: the lone star tick. And it wasn’t in the adult ticks — just the young ones, called nymphs.

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Unusual Tick-Borne Virus Lurks In Missouri’s Woods

Last year, scientists got the chance to solve a medical mystery — well, at least half of it. This week the final puzzle pieces fell into place, as investigators tracked the newly identified virus to an eight-legged bug.

The mystery actually began with two Missouri farmers who came down with a strange illness in 2009. They had high fevers, diarrhea and nausea. Their platelet counts dropped dramatically, though they didn’t experience any abnormal bleeding.

Doctors thought it was a bacterial infection. But antibiotics didn’t help. So a quick-thinking physician at Heartland Regional Medical Center in St. Joseph, Mo., sent the men’s blood to the Centers for Disease Control and Prevention.

When virologists looked at the samples under the microscope, they discovered a virus that no one had ever seen before. They named it the Heartland virus, in honor of its origin and the Midwest.