Countries that require a yellow fever certificate

Three rules, and why they exist

Yellow fever entry rules come from the International Health Regulations, which allow a country to ask for proof of vaccination to keep the virus out. A country where the virus circulates often asks every visitor, to protect travelers and to limit spread. A country without the virus but with the Aedes mosquito that can carry it, as in much of Asia, the Middle East and the Caribbean, asks only travelers who come from a country with risk, since only they could bring the virus in. A few countries publish their own list of the countries they check rather than refer to the WHO list. None of these rules says anything about whether the vaccine is useful for the trip; that is CDC's recommendation, a separate line on each country page.

The full list

The table lists every destination whose CDC page states a yellow fever entry requirement, grouped by rule. The age column is the minimum age the rule states, and the transit column marks rules that count a stay of more than 12 hours in an airport of a risk country. The last column is CDC's own vaccine advice for the country, which can point the other way.

Countries that name their own list

5 countries do not refer to the general list of countries with risk but name the ones they check: Costa Rica (Trinidad and Tobago, French Guiana (France), Mauritania, Venezuela and 39 more); Dominican Republic (Brazil); Ecuador (Democratic Republic of the Congo, Colombia, Bolivia, Brazil and 2 more); Paraguay (Venezuela, Bolivia, Brazil, Peru); Venezuela (Brazil). A traveler arriving from a country that is not named needs no certificate there, even if that country has some yellow fever risk. Those lists change more often than the general rule, after outbreaks or diplomatic decisions, which is a reason to read the CDC page close to departure and to confirm with the embassy. In the table, the number in brackets is the count of countries the rule names; the checker above applies the list itself.

For 2 territories, the CDC page states a requirement in terms the site could not reduce to one of the three rules; the table sends to the CDC text for them.

When the rule and the advice disagree

88 countries ask some arrivals for a certificate although CDC does not recommend the vaccine for a visit there, India, Thailand and Tanzania among them. The reverse also happens: Kenya, where CDC recommends the vaccine for most areas, asks for the certificate only from travelers arriving from a risk country, so a traveler flying in from Europe or North America may enter without one and still be advised to have it. The two questions are answered separately, and the trip checker on the home page shows both for each stop of an itinerary.

The order of the stops

Because most rules depend on where the traveler arrives from, the order of an itinerary matters. A safari in Kenya followed by a beach week in Zanzibar can call for a certificate at the Tanzanian border; the reverse order may not. A connection of more than 12 hours in Nairobi or Addis Ababa on the way to Asia can trigger the rule of a country such as Thailand or India. A traveler without a valid certificate who meets a rule can be refused entry, vaccinated at the border, or quarantined; India, for example, can isolate travelers for up to six days. The ten days the certificate needs after vaccination make the timing part of the plan.

Exemptions and waivers

Most rules exempt infants below the age they state. A clinician can also sign a medical waiver on the certificate when the vaccine is contraindicated, for instance in pregnancy or with a weakened immune system. Countries usually accept it but are not obliged to, and some ask for a letter on letterhead as well. The yellow fever vaccine page covers who should not receive the vaccine, and the price page what it costs in the United States.