"All of us have our fingers crossed, and everyone acknowledges that with every day that passes, the risk diminishes," said Dr. William Schaffner, chair of preventive medicine at Vanderbilt University in Tennessee. "Although at 42 days, I'm sure people are taking a deep breath, but the reality is that they're not completely out of the woods yet."
Going forward, the CDC is encouraging people who have received the tainted shots to be vigilant about keeping track of their symptoms, and to seek medical help if necessary, Chiller said.
But even the people who got meningitis and were treated are not in the clear. The CDC has now learned that those patients are coming back with abscesses filled with fungus and pus located near the injection site.
"The new finding is that patients during treatment or reaching the end of their treatment may actually relapse and come back with new symptoms," said Schaffner, who used to be president of the National Foundation for Infectious Diseases.
Schaffner said that the abscesses, which are located just outside the spinal casing, or dura, can grow and make their way into the dura, causing a meningitis relapse.
In some patients, the abscesses are present when they receive their first meningitis diagnosis, Chiller said. In others, the abscesses form several weeks later. These pockets of infection are often treated with oral antifungal medications or surgically drained, he said.
"This has been an unprecedented event," Chiller said. "It's a new entity to us, and we're trying to engage experts in the fungal and clinical word."