In the last few days, the virus has claimed nearly 40 lives in a string of major metropolitan areas.
But that number could go even higher, as doctors are increasingly seeing people in their 60s, 70s and 80s returning to the city from nursing homes.
The Centers for Disease Control and Prevention (CDC) has warned of an unprecedented pandemic, with more than 200,000 cases in the US and 1.4 million deaths.
The CDC is also warning that many people who remain in nursing homes or other institutions may be at risk of contracting the virus, which can cause fever, headaches, muscle aches and other symptoms.
This week, the CDC released a report that details the latest data on the virus.
Here are some things you need to know about the pandemic.