ATLANTA (NewsNation Now) — The number one tip to avoid phone scams is “don’t answer calls from unknown numbers,” according to the Federal Communications Commission, but amid the coronavirus pandemic, another federal agency is saying you may want to pay attention.

That’s because a state or local health department could be trying to tell you that you’ve been exposed to COVID-19, according to the Centers for Disease Control and Prevention.

Contact tracing is a way to notify people who were around someone diagnosed with COVID-19.

“If someone from the health department calls you, answer the call to help slow the spread of COVID-19 in your community,” the CDC said.

Those numbers may show up as an “unknown number.” The CDC said to at least be sure to check your voicemail from unknown callers.

According to the federal agency, contact tracing discussions are kept confidential and the information can only be shared with your doctor. In addition, if a contact tracer needs to call the people you’ve come in contact with, they will not disclose your name. The health department will only notify people who were within six feet of you for more than 15 minutes.

You still want to watch out for scams. The CDC warns that during contact tracing, a health department will not ask for: money, Social Security numbers, bank account information, salary information or credit card numbers.

Some states have partnered with Apple and Google to send you exposure notifications when you may have come in contact with someone who tested positive for the virus.

Currently, Alabama, Delaware, Nevada, North Dakota, Wyoming, Virginia and Guam have built apps that support exposure notifications. Apple said more states will be added soon.

According to the two companies, the data is shared by sending random numbers through a Bluetooth connection to other devices, the apps don’t track your location and Google, Apple and other users cannot see your identity.