America: which are the countries most affected by covid?
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(CNN) —
The US Centers for Disease Control and Prevention (CDC) included two destinations in South America, a country in the Middle East and a nation in North Africa in its category of "high" risk to travel.
The CDC adds the Dominican Republic to the "high" risk list for covid-19
On Monday, four destinations were moved to Tier 3, or "high" risk:
• Peru
• Bolivian
• Lebanon
• Tunisia
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Peru, known for the culinary excellence of its capital and notable Inca ruins in the Andes, was previously listed as Tier 2, "moderate" risk.
Bolivia, Lebanon and Tunisia were also included in Tier 2 last week.
Top image: A view of the valley of the Pinkuylluna archaeological site in Peru.
(Anna Gorin/RF Moment/Getty Images)
The CDC revised its rating system to assess COVID-19 risk to travelers in April.
Level 3, or "high," is now the highest rung in terms of risk level and applies to places that have had more than 100 cases per 100,000 people in the past 28 days.
Level 2 and Level 1 are considered "moderate" and "low" risk, respectively.
There were about 115 Tier 3 destinations on July 11.
Tier 3 locations represent nearly 50% of the approximately 235 locations monitored by the CDC.
Level 4, previously the highest-risk category, is now reserved for only special circumstances, such as places with extremely high case counts, where a new variant of concern emerges, or where healthcare infrastructure collapses.
Under the new system, no Tier 4 destinations have been placed so far.
More about Level 3
Much of Europe has remained in Tier 3 for months with the summer travel season in full swing.
As of July 11, the following popular European destinations were in Tier 3:
• France
• Germany
• Greece
• Ireland
• Italy
• Netherlands
• Norway
• Portugal
• Spain
• United Kingdom
Those aren't the only high-profile places that are in Tier 3. Many other destinations around the world are in the "high" risk category, including the following:
• Mexico
• Brazil
• Costa Rica
• Canada
• Malaysia
• South Korea
• Thailand
• Turkey
The CDC recommends travelers be up-to-date on their COVID-19 vaccinations before heading to a Tier 3 destination. Being "up-to-date" means you've received not only your initial full vaccinations, but also any boosters for which be eligible.
Level 2
Destinations carrying the "Level 2: Moderate Covid-19" designation reported 50 to 100 cases of Covid-19 per 100,000 residents in the past 28 days.
The CDC listed only one place in this tier on Monday: Fiji.
Fiji was upgraded from Tier 1, "low" risk category.
There are 16 places in the "moderate" risk category this week.
You can view the CDC's risk levels for any global destination on the agency's travel advisory page.
In its broader travel guidance, the CDC recommends travelers be up-to-date on their vaccinations before traveling internationally.
Level 1
To be listed as "Tier 1: Low Covid-19," a destination must have had 49 or fewer new cases per 100,000 residents over the past 28 days.
Only one place was added to the category on July 11: Romania.
The move to Tier 1 is good news for Romania, which was in Tier 2 last week.
There are more than 40 places in the "low" risk category this week.
Some of the most popular places in the "low" risk category this week include Indonesia, India and the Philippines.
Unknown
Finally, there are the destinations that the CDC has deemed to be of "unknown" risk due to a lack of information.
Usually, but not always, these are small, remote places or places with ongoing wars or riots.
Four places were added to this category this week:
• Armenian
• Laos
• Liberian
• Mongolian
Armenia and Liberia were previously in Tier 1. Laos and Mongolia were in Tier 3.
The CDC advises against traveling to these places precisely because the risks are unknown.
Other destinations in this category that usually attract more attention from tourists are French Polynesia, Macau and the Maldives.
Medical expert assesses risk levels
Transmission rates are just "a guideline" for estimates of personal risk for travelers, according to Dr. Leana Wen, a CNN medical analyst.
We have entered "a phase of the pandemic where people need to make their own decisions based on their medical circumstances as well as their risk tolerance when it comes to contracting Covid-19," said Wen, who is a physician at emergency room and professor of health policy and management at the George Washington University Milken Institute School of Public Health.
There are other factors to consider besides transmission rates, according to Wen.
"Another is what precautions are required and followed where you're going and then the third is what do you plan to do once you're there," he said.
"Do you plan to visit a lot of attractions and go to closed bars? That's very different than going to a place where you plan to be on the beach all day and not interact with anyone else. That's very different. Those are very different levels of risk." .
Vaccination is the most important safety factor for travel, as unvaccinated travelers are more likely to get sick and transmit COVID-19 to others, Wen said.
And it's also important to consider what you would do if you end up testing positive away from home.
While US-bound travelers no longer have to provide a negative COVID-19 test to return home, the CDC still recommends testing before boarding flights back to the US and not traveling if you're sick .
"Of course, if people have symptoms or exposure while traveling, they should get tested, and if they test positive, follow CDC isolation guidelines," Wen told CNN Travel recently.
If you are concerned about a specific travel health situation unrelated to covid-19, check here.
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