Numbing Agent

Why are so few people reporting negative health effects caused by radio frequency electromagnetic fields?

Because RF can, in fact, prevent nerves from telling the brain that the body is feeling pain.

From Wikipedia (for what it's worth):

RFA, or rhizotomy, is sometimes used to treat severe chronic pain in the lower (lumbar) back, where radio frequency waves are used to produce heat on specifically identified nerves surrounding the facet joints on either side of the lumbar spine. By generating heat around the nerve, its ability to transmit pain signals to the brain is destroyed, thus ablating the nerve. The nerves to be ablated are identified through injections of local anesthesia (such as lidocaine) prior to the RFA procedure. If the local anesthesia injections provide temporary pain relief, then RFA is performed on the nerve(s) that responded well to the injections. RFA is a minimally invasive procedure which can usually be done in day-surgery clinics, where the patient is sent home shortly after completion of the procedure. The patient is awake during the procedure, so risks associated with general anesthesia are avoided. An intravenous line may be inserted so that mild sedatives can be administered. The major drawback for this procedure is that nerves regenerate over time, so the pain relief achieved lasts for only a short duration (6–24 months) in most patients.

Those who respond unfavorably to RF exposure could be considered lucky because this "allergic reaction" is a helpful warning mechanism telling them DANGER, DANGER! Most people, in the presence of a cell phone, cordless phone, WiFi, or other device emitting a constant signal do not feel the effects because their nerves aren't working properly. In some ways, this is no different from the way other pain relievers work. As long as the "dose" is consistent and doesn't cause too much impairment, the end result is that an individual might actually prefer the RF exposure over no RF.

But what happens if the "dose" isn't consistent or stops completely?

That's when it usually hurts. That's why so many people are becoming electrosensitive after having a Smart Meter installed—not because it's a novel frequency (we've been using 915 Mhz in consumer devices for 25 years and in Industrial, Scientific and Medical applications much longer), or because the power is incredibly high (what's a few watts?).

It's due to the digital/pulsed/binary nature of the signals.

The question remains:

Why is it so hard for utilities and other SmartMeter stakeholders to understand why these strobing RF generators are such a hazard?