watch the country of origin when buying fish

Those sickened are being held in isolation in medical facilities in Wuhan. Their main symptom is fever, according to the World Health Organization. But some patients have also experienced trouble breathing, and chest X-rays have shown invasive lesions in both lungs.

Though Wuhan health officials are closely monitoring 163 people who had close contact with those sickened, there's no evidence so far that the illness is spreading from person-to-person. No medical staff members have become ill in the outbreak, either. Those are both promising signs for containing the outbreak and stamping out the disease.

Wuhan officials report that the outbreak erupted in the latter half of December. Among the cases identified so far, the earliest onset of symptoms was pinned to December 12 and the latest illness began December 29.

Survey data collected during that window indicated that some patients with the mysterious pneumonia were working at the Wuhan South China Seafood City. The market sold seafood, but also chickens, bats, marmots, and other wild animals. According to The Washington Post, it was a 1,000-booth bazaar that state media reports labeled as "filthy and messy."