I emplore you to really read up on your bloodborne pathogens and universal precautions because the information is a huge way to lower your risks...some risks are not under your control, but informing yourself is under your control and your biggest defense! You should know this stuff if you are going into healthcare, or even if your not...everyone should know it in my opinion. (it isn't like non medics don't find themselves in situations where bodily fluids are involved...like car accidents, CPR need, helping a friend with a laceration, etc.).
You will never find a safe enviroment as long as you work with humans when it comes to bloodborne paths! Comes with the territory, and a risk all healthcare folks take daily. Best to be as informed as you can be...rationally informed mind you...some folks get overly scared reading the info...you must be rational! But all in all it is the defense you chose that lowers or increases your risks!
Say you have a patient that has been vomiting for quite some time and now has blood in their vomit (this can happen in any specialty!). What precautions should you use? Gloves are a given, and are typically what most people rely on, but how about mask and eye protection or even a disposable cover for your uniform? Being informed and knowing the situation will help you to chose...like me, I know that vomit can be projected pretty well in small droplets so I will be protecting my own mouth, nose, eyes since they will be the closest to the patient..gloves a given for me..and protection for my uniform because I will be in contact with surfaces and others and should be alert to what I may spread to others! That will not only lower my risk to exposure, but others too...and that is what a good medic takes into consideration! And washing exposed skin...you betcha! (hair too...watch your hair or any dangling objects like lanyards or jewelry).
If you are overly scared of these things, you may choose to really learn about it in school so you are best prepared! I took on things that I feared or was intimidated with during nursing school so that I got accustomed to them...I guess that is why the ED wound up being my favorite!!!! You mentioned oncology...ask your dad about the risks there...you have radiation risks from implanted therapies, lots of vomiting and incontenence, lots of pain issues which can mean shots and iv's, high risk of exposure from YOU or others towards your patients who are comprimised on immunity, etc! So here too you have your risks..best to be informed and strive to lower your own risks via education and information!
All and all..the safest field of nursing if you are worried about these issues...well, not to get into it at all
...since that won't work...learn as much as you can about it...and be a proactive person too by teaching others!
Now that is a win win!