The CDC considers a Level 4 category any country that has an infection incidence of over 500 per 100,000. Luxembourg, with its total population of roughly 635,000, and active infection cases of 2,041, joins the highest alert level alongside the Cayman Islands, Faroe Islands and Netherlands. Belgium, the UK, Switzerland and Austria also feature on the long list. 

Level 4 countries--80 worldwide as of 8 November--should be avoided, recommends the CDC. Those with a complete vaccination card, though less likely to catch the virus, according to the CDC’s website, also have to undergo a PCR test prior to returning to the US. 

Luxembourg has seen an increase of 14% of new infection cases over the last days, indicating, according to Jean-Claude Schmitt, Luxembourg’s chief medical officer, a potential 

s to fully vaccinated US visitors. The US had also just reopened its borders to EU citizens after 20 months.  

The US on 8 November announced that Luxembourg is considered a “very high risk” country. The Center for Disease Control and Prevention (CDC) recommends avoiding travel to the grand duchy or to be fully vaccinated.