That would depend on how you define "frequent masturbation" and "reduced sperm count." I'll start with the long-term concern. In the long run, no, masturbation is no different than intercourse in terms of effects on sperm count or quality. In men, sperm are continuously produced, so even if you were to have a sufficient number of ejaculations in a day to noticeably deplete your sperm count, there will be more within 24 hours.
When fertility clinics check sperm count, they will ask the man to abstain from both intercourse and masturbation for a few days to get an accurate assessment. This gets at another part of your question...what is sperm count. The way most people mean sperm count refers to the number of live, normally motile sperm (don't have any extra heads or tails...with millions generated every day, there are defective sperm in every man's semen, but the percentage of these is usually very low if everything is healthy) in a volume of semen (usually in a milliliter). More frequent ejaculation (again, regardless of whether it is through masturbation or intercourse or any other means) will not increase the amount of sperm produced in a day, but neither is this amount decreased. That number produced WILL be diluted more with more frequent ejaculation, so the number of sperm per volume of ejaculate (the measure of sperm count I described above) will decline measureably (though not anywhere near zero) if you are ejaculating frequently (more than once or twice per day), but with a brief period of abstinence, all will be normal again. So, again, it is not permanent at all.
The only time the reduction in sperm per ejaculate becomes an issue, clinically, is if a couple is attempting to conceive and having difficulty, in which case the first suggestion a physician will make is for the man to abstain from masturbation between sessions of intercourse if there is any concern that this is contributing to the fertility problems.