In a study published in Retrovirology, Dimitrios Paraskevis and his team at the University of Athens tracked how tourists got infected with HIV whilst on holiday and how HIV piggybacks on migrants traveling from one country to another.

Significant HIV migratory pathways across Europe.
Arrowheads indicate the targets of migration shown in
different colours and styles by country of origin.

“Specifically, Greece, Portugal, Serbia and Spain, provide sources shedding HIV-1; Austria, Belgium and Luxembourg, on the other hand, are migratory targets, while for Denmark, Germany, Italy, Israel, Norway, the Netherlands, Sweden, Switzerland and the …