What the International Certificate of Vaccination or Prophylaxis is, who needs it, the 10-day rule, exemptions, replacements.
What it is
The World Health Organization's International Certificate of Vaccination or Prophylaxis (ICVP), commonly called the 'yellow card'. It is the only vaccination record permitted to be required by states under the International Health Regulations (2005). For yellow fever it is the standard proof of vaccination accepted at all ratifying ports of entry.
Who needs it
Every seafarer travelling to, from, or via a country with yellow-fever risk (most of sub-Saharan Africa, parts of South and Central America), and any seafarer joining a vessel calling at such a port. Some destinations require an ICVP even from passengers transiting briefly.
When it is checked
Airport immigration on entry to a yellow-fever-risk country.
Onboard at sign-on where the trading route requires it.
Port-state-control / port health authority checks at risk ports.
Common mistakes
Vaccination dated less than 10 days before travel — not yet valid; immigration may refuse entry.
Black-and-white photocopy submitted in place of the original — many ports require the colour original.
Yellow card lost — the vaccine itself is valid for life but the card must be replaced via the issuing clinic or national health authority.
Treating a written exemption letter as automatic acceptance — the destination country decides what it accepts.
Validity
WHO recognises yellow-fever vaccination as valid for life since 2016 (no booster required for international travel). The card itself remains valid for life unless a country specifies otherwise.
If lost or expired
Return to the issuing clinic / national authority for a replacement. Some countries can re-issue from immunisation records; others require a re-vaccination. Carry a phone photo of the card before flying.
Printable checklist
Original yellow-fever ICVP (yellow card) in colour, dated 10+ days before travel.
Phone photo + cloud backup of the card.
Vaccination cross-checked against the destination country's published requirement.