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.)