A Leader plans to visit several countries in a few days/weeks, one of the countries plans to contaminate certain food and drink (or utensils) served at the state dinner with hard-to-detect substance or organism whose effect will turn symptomatic days/weeks after ingestion.
Could the Leader's team prevent such detriment without breach of protocol?
If the Leader's team fails to prevent the detriment, could they figure out which country did it?