(CNN) – The 2021 summer travel season started full of hope and promise, but every day, two words threaten to bring it all down: delta variant.
This more transmissible variation of the new coronavirus was first detected in India in February, just as the United States and some other places in the world were beginning to really prepare their vaccination efforts. It turned out to be a race against time: vaccines against the delta variant. And like all the other waves of the pandemic, travel feels the impact of the fast and strong covid.
From new travel advisories, issued this week, to Google searches on the subject in the last 24 hours, it is clear that the delta variant is causing increasing concern and disruption for governments and would-be travelers.
New US Travel Advisories
The Alfama neighborhood can be seen in Lisbon. The United States moved Portugal to a “Level 4: Do Not Travel” advisory on Monday. Photo: Patricia de Melo Moreira / AFP via Getty Images
On Monday, the US State Department and the Centers for Disease Control and Prevention (CDC) issued new warnings for five countries, citing the increase in COVID-19 cases:
– Cyprus (Level 4: Do not travel)
– Israel (Level 3: Reconsider traveling)
– Kyrgyzstan (Level 4: Do not travel)
– Portugal (Level 4: Do not travel)
– Spain (Level 4: Do not travel)
The warning not to travel to Spain is particularly significant as it is one of the most popular destinations in the world.
However, as of Tuesday, those five places were still allowing American tourists to enter if they meet certain restrictions, according to the State Department listings. This occurs even as the United States is dealing with its own outbreak of the delta variant.
Other places that advise not to visit

The pandemic has hit São Paulo and the rest of Brazil hard. Shutterstock
Spain and Portugal join a growing list of popular travel destinations in the “Level 4: Do Not Travel” category, which is the highest on the State Department scale. Level 4 is also the highest alert for the CDC.
Some of the other places on Level 4 starting Tuesday that are traditionally popular with travelers from around the world:
– Argentina (which has been closed to most international tourism during the pandemic)
– Brazil (which has had a liberal policy towards visits despite being one of the countries most affected by the pandemic)
– Maldives (these tourism-dependent Indian Ocean islands allow most visitors minus some South Asian countries)
– The Netherlands (which opened its doors to American travelers on June 24 and welcomes most of Europe – see a full list of “safe countries” from Netherlands here.)
– South Africa (many nations will not allow visitors if they have recently been to South Africa)
– United Kingdom (the CDC warn that even if you are fully vaccinated, you may be at risk of contracting and spreading variants of the new coronavirus)
You can view the full notice lists of the Department of State and of the CDC from Level 4 to Level 1 (low risk) here.
White House: Existing restrictions will remain for now
More evidence of growing concern and its effect on travel:
On Monday, the White House decided to keep existing coronavirus travel restrictions in place, Press Secretary Jen Psaki said.
“We will maintain the existing travel restrictions at this point for a few reasons. The most transmissible delta variant is spreading both here and around the world,” Psaki told reporters. “Driven by the delta variant, cases are increasing here at home, particularly among those who are not vaccinated and it seems likely that they will continue in the coming weeks.”
The announcement came as the Biden administration has come under increasing pressure from the travel industry and US allies.
People who have been to Brazil, China, the European Schengen Area, Iran, India, Ireland, South Africa and the United Kingdom in the past 14 days are denied entry to the United States.
What people want to know: at least on Google

Mexico has maintained a fairly liberal travel policy during the pandemic. This is a general view of the archaeological area of the Templo Mayor, a popular tourist spot in Mexico City. Ronaldo Schemidt / AFP / Getty Images
If you want to know what’s on people’s collective minds, just check Google searches. The delta variant is an upward trend.
Global searches: Around 1:30 pm Miami time on Tuesday, Google Trends posted a 100% increase in searches for the term “delta variant travel restrictions” in the last 24 hours worldwide.
Other increasing searches around the world focused on restrictions for particular locations: Victoria (Australia) and Mexico led the way.
In the state of Victoria, Australia, they are expected to end their fifth lockdown this Wednesday, including as they narrow the border with neighboring New South Wales, according to the newspaper. The Guardian. (Victoria has the city of Melbourne, while Sydney is in New South Wales).
Australia has maintained some of the strictest travel restrictions in the world since the pandemic began, only opening to New Zealand on April 19. But that “travel bubble” has been fragile and collapsed again on July 23.
Mexico, on the other hand, has had the opposite response. It has been, and continues to be, one of the easiest countries to visit.
Its land border with the United States has been closed for more than a year, but air traffic has been flowing in from around the world. You don’t even have to provide a negative PCR test result or quarantine upon arrival. Mexico was at “Level 3: High” on the CDC advisers list.
People around the world were also looking to the US for guidance on broader concerns with searches for “US International Restrictions.” o “CDC restrictions” that also increased in the last day.
Searches in the US: Search queries originating in the United States are primarily oriented abroad. At this time, very few US states have national travel restrictions despite the sharp increase in infections among the unvaccinated.
There was a 450% increase in search in 24 hours for the term “Spain travel warning”, spurred by Monday’s announcement. And also big spikes for more general international searches, like “Can US citizens travel to Europe?”
The answer to that second question varies by country and day, as restrictions are constantly changing. But most of Europe, including heavyweights such as France and Germany, was opened to American citizens earlier this summer and remained open Tuesday despite the fact that the United States’ travel ban continues to block many Europeans.

Greece is a growing search term on Google in the UK. And it is open for people who want to visit places in Greece like Santorini. Shutterstock
Searches in the UK: In the United Kingdom, the United States and Greece were those of greatest international interest.
For travelers from the United Kingdom eager to visit the United States, the ban remains in effect for them.
As for Greece, it was one of the first European countries to reopen. It is open to travelers from the UK and many others around the world. The countries of the EU and the Schengen Area can visit, in addition to places like Canada, China, Japan, the United States and the United Arab Emirates.
Domestically in the UK, there has been a large increase in search interest, over 2,600%, over Scotland’s plan to offer free bus rides for young. It would be for people under the age of 22 as of January 31, according to the BBC.
CNN’s Jeremy Diamond and Kate Sullivan contributed to this story from previous reports.