the rats on the boat carried the fleas that carried the plague while on the ship, contaminating everybody aboard the ship, this later resulted in a bigger, and faster spread of the plague
food was decent lets find a hotel to get some Z's
yo this food slaps
this is where it goes wrong, all of the people on the ship get off and go into town, WHILE INFECTED they do not know they are infected though because the incubation time for the plague was 1-6 days.
what a long day of bartending, i cant wait to see the family!
this is when the men are walking into town to look for some food after the long trip, they go into multiple restaurants looking for food, in this process they put they're hands on multiple things and touch many people, causing the spread of the disease.
of course kiddo! wheres my hug?
they find a restaurant to eat at, they tell the workers to get them whatever they want and that they had just arrived from a long trip from Europe, the workers then insist they have somebody show them around the area, this causes more spread of the plague
the contaminated workers then go home and give the plague to everybody they see in that time, still not knowing that they have a deadly disease because of the incubation time.
this is the husband, kid, wife, and other kid all leaving the house for school the next day, they find out grandma showed up at there house extra early, they give grandma big kisses and hugs contaminating her, she goes back to the elderly home and gets them all sick.
Bye Grandma! it was great seeing you before school.