influenza

Frustrated scientists argued Wednesday that making nasty viruses even worse in the lab provides crucial insight into preventing pandemics. Others say it just ups the risk a lab germ will start one.

It's still too soon to say whether this is a historically bad flu season. But it's already clear that emergency rooms around the country are filled with feverish throngs that are much larger than during the last flu season.

As students return to class from winter break, campus health official are trying to avert an outbreak. Colleges in Boston are especially worried after the mayor's declaration last week of a public health emergency in the city.

Vaccination is still the best way to avoid getting sick, but it's not 100 percent protective. Some people may get infected with a strain of flu that isn't covered by this year's vaccine. For others, the shots just don't work.