If this actually causes physical damage to a virus, it raises the question for me: what else do ultrasounds physically damage? Surely COVID 19 can’t be the only thing in our body with a resonance frequency in that range
Ultrasound is just sound above frequencies that humans can hear, which is a vast range from ~20khz up to practical physical limits, gigahertz at least. Your body has resonant parts that can be damaged by frequencies in the _audible_ range, the chief parts being in your ears but other parts, too, if the sound is sufficiently loud, e.g. a shockwave from a powerful explosion. So amplitude (volume) is clearly very important.
All that to say, I don't think there's any cause here to draw suspicion upon sonograms or other time-tested procedures.
Viruses are considerably smaller than cells, so that probably plays a part in damage. Though maybe we should study the effects on DNA and organelles within cells.
Also, the body regularly damages itself in attempts to eliminate infections. It then can heal. Ultrasound might damage other parts of the body, but it might not be worse than what the infection itself causes.
ultrasounds are done on people all the time, especially during pregnancy on relatively fragile fetuses. we'd likely know of any serious risks by now. ultrasound is more akin to microscopic shaking than a mysterious flux of (highly potent) energy.
also consider that the cov2 virus is particularly fragile, for instance, requiring the external support of water to remain intact. it's why you don't need masks in most common situations (just distance), because the virus disintegrates so easily.
some viruses, on the other hand, can essentially hibernate and revive themselves once inside a host. those are the ones that would require enough excess energy that damage to other cells and organelles might be a genuine concern.
The proposed ultrasound frequencies are 10-100 times as high as the ones usually used for imaging purposes, so the conclusion that it must be harmless does not naturally follow.
Agreed. You could substitute ultrasound waves with electromagnetic waves in this same conversation. We use EM waves every day for diagnotics -- at the 740-380nm range because that's visible light. 10x-100x frequency of that is ultraviolet, which is harmful. And as for resonant frequencies, it doesn't seem unreasonable to me that certain frequencies could denature certain proteins or have other effects.
i haven't delved into the specifics here, but note that a higher frequency doesn't necessarily mean a higher flux of energy, so that conclusion doesn't necessarily follow either.
It does not need a "higher flux of energy" to do damage. Exciting a system at its resonance frequency can increase the amplitude of its vibrations to the point that it gets damaged.
This does not take lots of energy, it does not take large amplitudes, just periodic input of power at the right frequency. Knowing that a system is fine at one frequency does not say (that) much about other frequencies.
yes, resonance can be significant, but that still doesn't necessarily mean that the energies here are significant, nor that the frequencies applied are the right frequencies, and resonant enough, for damage.
the underlying point is that unless we're capable of doing the relevant experiments ourselves, we need to trust that people in the field are cognizant enough to realize these obvious issues, test them, and report their findings. it's unlikely that lay people like us are going to find and gotcha the researchers in the field.
that's not to say that, in aggregate, we can't give researchers ideas about what to be researching. that, we can--and should--do, via conversations like this.
> yes, resonance can be significant, but that still doesn't necessarily mean that the energies here are significant, nor that the frequencies applied are the right frequencies, and resonant enough, for damage.
I did not claim that the proposed method has to be harmful. I stated that ultrasound imaging gives little to no insight in what happens at frequencies that are an order of magnitude or two higher than that. The second reply was an attempt to do away with the misconception that "higher flux of energy" was necessary for damage.
Great point. If you've never had an ultrasound, it's safe enough that the technician doing them (who may see dozens of patients in a day) isn't even wearing any shielding or protection.
Not only is it highly directed, ultrasonic acoustical frequencies disperse very quickly in air. At 1MHz, the energy absorption in air is ~160dB/meter, so a person sitting at arm's length away from the emitter (even if it weren't highly directed) would receive ~6*10^-17 of the power (if that weren't far below any possible noise floor, which it is).
> “We’ve proven that under ultrasound excitation the coronavirus shell and spikes will vibrate, and the amplitude of that vibration will be very large, producing strains that could break certain parts of the virus, doing visible damage to the outer shell and possibly invisible damage to the RNA inside,” says Tomasz Wierzbicki, professor of applied mechanics at MIT.
Why say they have proven it, when all they have done is a simulation and they have not demonstrated anything? It seems like they have a hypothesis, not that they have "proven" anything.
Also, at least as a layman, the RNA comment makes me a little worried about this technique leading to the accidental creation of a stronger mutant virus.
Might work wonders in being applied to air filters or disinfecting large spaces. Not sure if you could run this continuously especially when humans are around.
This is not very convincing, though of course it should be followed up on. Considerably more is known about the structure of the virus than the article seems to imply.
I'd like to see more about what they mean by simulations "in water". If they didn't simulate intermolecular forces at all, these results seem unlikely to be relevant.
The details really matter here. Many early visualizations of the spike protein only showed the protein amino acid residues, not any attached sugars (glycosylation). Turns out the sugars act as a reconfigurable armour that was preventing targeting of the spike protein by meds.
The theory that a bat virus would be damaged by the same type of sounds that bats produce non-stop for hours feels very strange to me. If true, this coronaviruses should be extinct since millions of years ago. No one single virus would stand the extra loudly bat colonies. Specially not rabies virus that has a much more fragile structure.
As this does not seem to happen, my bet is that will not work as expected. My instinct might be wrong, of course.
Fair point. And there is a difference also between one bat and a thousand bats clicking at the same time in a colony and overlapping the calls. Either the singing is perfectly synchronised or those 0,2MHz would be higher. If the claimed effect is real then, hypothetically, the bigger the colony the less virus that we should find on it.
This may happen or not. I don't have this data. Nobody studied it still from this point of view (If I'm not wrong).
...not really, no. The supposed mechanism of action here is resonance. You can't generate energy in the 25Mhz range by overlapping a bunch of 200Khz tones, any more than a crowd of humans can generate ultrasound by yelling.
