Hi Fatima. Seems to me that people with compromised immune systems will be more likely to get sick than those with good immune systems. If this man only visited for 30 minutes and ends up having Ebola, maybe he has AIDS or some other disease.
As a fomer infectious disease nurse your assumption is simply incorrect.
First it is unlikely he has ebola. Second this virus is transmitted through infected body fluids, so basically it would come down to him being unlucky enough to having touched something that had infected fluids on it and then the virus either entering through broken skin or mucous membranes ( for example rubbing his eyes or nose, or say going to lunch after his apartment visit without washing his hands first)
All of this talk of space suits, expensive respirator masks, goggles etc is a bit misleading. First line of defense should always be proper hand washing something Americans stink at. Every time you come home from going out, every time you use the bathroom and always before you eat and prepare food. Use a good bacterial soap and scrub all surfaces of hands through two renditions of “happy birthday” Kills ebola and influenza too! Incidentally hand sanitizer does not kill viruses only makes it more difficult for them to “stick” to your skin.
Also interesting reading is the story of a senior nursing student in Liberia who single handedly treated successfully ( i.e. they lived) three out of four family members with ebola and never contracted it herself. Her secret.... meticulous infection control practices. She used trash bags, a cheap plastic rain coat and regular old cheap paper hospital masks... no fancy hazmat suits just excellent universal precautions. All the fancy outfits can’t protect you ( ask the spanish nurse) if you touch your nose or eyes with your (contaminated ) gloves.