The Black Death moved from region to region carried by fleas which then infected animals such as marmots, rats, and camels, who themselves became carriers.
-The Mongol Storm, Nicholas Morton
Camels carried other things as well, Rukāb, Riders, we were called- Ticks, Lice, and Men- and in some cases a camel carried a rider ridden by another rider, a drover riding a camel and a flea riding the drover.