Yes, you can get nail fungus have fake nails. The fungus that causes this condition is common, so all that can act as a trap, such as a false nail, or irritants, such as adhesive nail, can be a problem.
Causes
The gap between fake nails and nails can trap water, dirt and anything else. If fungus grows in a gap like that, will have no place to go, but in your nail.
Symptoms
Symptoms of nail fungus can include yellow nails, thick, rough or dilapidated that are painful and smelly.
Prevention / Solution
The best prevention is to not use fake nails. If you choose to get fake nails, there are steps you can take to try to prevent this condition.
Have your nails done by a nail technician specializing; are more likely to avoid gaps between the false nail and the nail. Keep your hands clean.
Treatment
Nail fungus under the fake nails is difficult to cure. The fungus has become and is protected from the nail. Because the nails grow slowly, any infected area tends to infect and reinfect the areas around it.
You may find topical treatments at the pharmacy, but according to the Mayo Clinic, do not work very well. The only proven treatment is to take a long course of oral antifungal.
Risks
Oral antifungal medication can be hard on your liver. If you have impaired liver function, for any reason, your doctor will prescribe the drug for you.