Salmonella enteritidis infections from consuming eggs can cause serious illness in susceptible people.

Those hens laid 550 million eggs tainted with a toxic strain of Salmonella enteritidis, which in turn ended up on grocery store shelves.

However, 50 percent of infections resistant to the fluoroquinolone drug nalidixic acid were caused by Salmonella enteritidis, the most common salmonella type.