in what ways could the virus have been passed to other peoplefrom the time monet lefthis house untill he arrived at nairobi hospital

Basically Monet is described as a human Marburg virus bomb. Basically anything expelled from his body was filled with virus that could be transmitted to others. 

The human virus bomb explodes…The victim has “crashed and bled out.”…He becomes dizzy and utterly weak, and his spine goes limp and nerveless and he loses all sense of balance….He leans over, head on his knees, and brings up an incredible quantity of blood from his stomach and spills it onto the floor with a gasping groan. He loses consciousness and pitches forward onto the floor. The only sound is a choking in his throat as he continues to vomit while unconscious. Then comes a sound like a bedsheet being torn in half, which is the sound of his bowels opening and venting blood from the anus. The blood is mixed with intestinal lining. He has sloughed his gut. The linings of his intestines have come off and are being expelled along with huge amounts of blood. Monet has crashed and is bleeding out.”