The terms (ways) of infection are as following

Blood: A drop of blood going somehow into your bloodstream.Also the regurgitation of blood is a possibility as it would go into your eyes,mouth and possibly nose.

Bite: A bite from a zombie is the most well known term of infection. Commonly used in films and games such as Shawn of the Dead,resident evil,dawn of the dead,dead rising and other popular franc

Fluids: If you are fighting a zombie hand to hand, although highly inadvisable. If you split the skin on your knuckles and some sweat,blood or other type of bodily fluid goes into your skin you may as well turn a gun on yourself.


Resident Magnum

Many movies show that the infection can happen very quickly or very slowly depending on the person and the type of method for the infection

1. If a person dies from a wound or wounds then they become a zombie
2. Bite there are a few films out there that argue sometimes people can live and not turn from a bite while others argue that a bite is just as dangerous as dying and then becoming a zombie
3. Fluid not a bite but the blood of a zombie in some films the hero maybe covered head to toe in zombie blood but never turns while in a few films the fluid turns a victim very quickly
4. Gas or vapor, if the dead zombies are burned or if there is a canister that leaks it could kill the living then those infected would get back up and become zombies
5. Scratches this can sometimes turn people into zombies best to avoid being scratched

The evidence shows that if the zombie plague were a real plague not everyone would become a zombie regardless of infection and many others would turn even if breathed on. So if one is going to survive take precautions. use a gas mask it may filter the toxins from infected you or buy time, it will also block to a limited degree zombie vomit from infecting you. Wear heavy clothing to avoid being bitten or scratched.

Also regardless of infection amputation never works it only buys time and sometimes makes the victim die even quicker because of blood loss / shock / trauma / infection from normal diseases. Except if you have a zombie virus like the one in 28 days later and 28 weeks later than you can be infected and not turn into a zombie.

Also in all the movies those who survived for prolonged periods of time other than Frank West in Dead Rising,
no one ever lived longer than three days with out military training and/or superpowers or immunity. and don't expect to be immune.