The CDC is warning travelers about visiting 5 countries because of coronavirus. Here's the US government's guidance for Americans.

The following countries and territories have increased guidance from the CDC:

The CDC cautions that if any traveler returning from one of these areas feels sick with a fever, cough, or shortness of breath, they should immediately seek medical help, call ahead before going to the doctor, avoid travel, avoid contact with others, and exercise increased sanitation.

The following countries or territories have reported cases of the coronavirus but the CDC has not issued specific travel notices for them:

Afghanistan
Australia
Bahrain
Belgium
Cambodia
Canada
Egypt
Finland
France
Germany
India
Iraq
Israel
Kuwait
Lebanon
Malaysia
Nepal
Oman
Philippines
Russia
Singapore
Spain
Sri Lanka
Sweden
Taiwan
Thailand
United Arab Emirates
UK
US
Vietnam

In some cases, the US embassies in these places have issued further guidance. You can check for that on the State Department's website, and some alerts are linked above.

Furthermore, "CDC recommends that all travelers reconsider cruise ship voyages to or within Asia."

Some cruises have had their itineraries changed or canceled. You can find out if your cruise has been affected by the coronavirus by checking social media, your cruise line's website, or your email. Business Insider's Mark Matousek compiled full instructions here.

The CDC issued its highest health notice for mainland China — Level 3, Avoid Nonessential Travel.

Due to widespread transmission of the coronavirus in China, the CDC and US State Department recommends that travelers should avoid all travel to the People's Republic of China.

The US State Department encourages anyone in China to depart the country by commercial means, and recommends that US citizens remaining in China should spend as much time at home and away from public gatherings.

At least 73 airlines have canceled flights to China amid coronavirus fears, and the US government evacuated some US citizens from the country.

The CDC also warns that older adults and people with chronic medical conditions have an increased risk of the disease. Furthermore, the agency outlined that those arriving in the US from China will undergo health screenings, and travelers who have been to China within the past 14 days must enter through specific airports and participate in monitoring by health officials until 14 days after they left China.

The White House has barred foreign nationals from China, Hong Kong, and Macau from entering the US, is quarantining Americans who recently traveled to China's Hubei province, and is asking Americans who visited other parts of China to "self-quarantine."

By Monday, February 24, China had reported more than 77,000 cases and at least 2,500 deaths from the disease.

The CDC issued its second-highest health notice for South Korea — Level 2: Practice Enhanced Precautions.

The CDC and US State Department warn that South Korea is experiencing an increase in transmission of the coronavirus, and recommend that older adults and those with chronic medical conditions should consider postponing nonessential travel.

The State Department also warned: "If suspected to have Coronavirus in South Korea, you may face travel delays, quarantine, and extremely expensive medical costs."

By Monday, February 24, South Korea had reported more than 800 cases and eight deaths from the disease.

The CDC also issued a Level 2: Practice Enhanced Precautions for Japan.

The CDC and US State Department warn that Japan is experiencing an increase in transmission of the coronavirus, and recommend that older adults and people with chronic medical conditions should consider postponing nonessential travel.

By Monday, February 24, Japan had reported more than 150 cases and one death from the disease.

The CDC issued its least severe health notice for Italy — Level 1: Practice Usual Precautions.

The number of coronavirus cases in Italy has spiked in the last few days, but the CDC lists the country as a Level 1 threat, and at this time does not recommend canceling or postponing travel.

The US State Department said the US Consulate General in Milan will suspend routine visa services until March 2 due to reduced staff.

Routine and emergency services for Americans in Italy will continue at the Consulate General in Milan, and full services are available at the Embassy in Rome and the Consulates General in Florence and Naples.

By Monday, February 24, Italy had reported more than 200 cases and six deaths from the disease.

The CDC also issued its lowest threat for Hong Kong — Level 1: Practice Usual Precautions.

The CDC does not suggest travelers cancel or postpone trips to Hong Kong at this time, listing it as its lowest "watch" level.

The US State Department reported that in early February, the Hong Kong government began enforcing a 14-day quarantine for anyone arriving in Hong Kong who has visited mainland China within the previous two weeks.

By Monday, February 24, Hong Kong had reported 79 cases and two deaths from the disease.

The CDC has issued its lowest threat for Iran — Level 1: Practice Usual Precautions.

The number of coronavirus cases in Iran has increased recently, but the CDC lists the country as threat Level 1, and does not recommend canceling or postponing travel to the country.

But the US State Department classifies Iran as a "Level 4: Do not travel" due to the high risk of kidnapping, arrest, and detention of US citizens.

Because the US government does not have diplomatic relations with the Islamic Republic of Iran, they are unable to provide emergency services to US citizens, and strongly recommend avoiding all travel to the country for security reasons.

By Monday, February 24, Iran had reported 61 cases and 12 deaths from the disease.