Why does IATA's Timatic (https://www.iatatravelcentre.com/) ask for the countries visited over the past 6 days when searching for a destination?
I understand that immigration officers sometimes need to look at the recent travel history when deciding whether to grant entry, but I wonder why choosing 6 days and not some other amount of days.
Some countries—notably India and Singapore—require arriving travelers to present a Yellow Fever Vaccination Certificate if they have been in a country where yellow fever transmission is endemic within the past six days. Other countries with this requirement are a bit vaguer about the exact timing, but six days seems a reasonable rule of thumb even in such cases.
