Diagnostic Ultrasound Could "Break" Envelopes of Viruses Like SARS-CoV-2 and H1N1

SARS-CoV-2 and H1N1 viruses, exposed to ultrasound between 3 and 20 MHz, showed collapsed and fragmented envelopes in laboratory tests. This promising technology aims to destroy viruses without harming human tissue, offering new hope in the fight against infections.

The battle against viruses is constant; today's treatments may be ineffective tomorrow, and developing new antivirals takes years. Existing physical methods like ultraviolet radiation or heat destroy viruses but unfortunately also damage human body tissues, preventing their direct use as medical therapies.

Facing this challenge, a team of researchers wondered if diagnostic ultrasound, a tool already common in hospitals worldwide, could directly affect the structure of viruses. The key was to destabilize and destroy the envelopes of viruses like SARS-CoV-2 and H1N1, without altering the temperature or chemistry of their environment.

To test this hypothesis, scientists took samples of SARS-CoV-2, including its Wuhan, Gamma, and Delta variants, along with influenza A (H1N1) virus. They exposed these to ultrasound in a range of 3 to 20 MHz for periods varying from 1 to 30 minutes, using clinical diagnostic imaging equipment—the same devices found in any healthcare facility.

To observe the effects, they employed scanning electron microscopy, which provides highly detailed images of the viral surface, and atomic force microscopy, capable of measuring the shape and stiffness of particles at the nanometer scale. These tools offered an unprecedented view of the structural changes.

The images revealed a dramatic impact: treated viral particles exhibited irregular surfaces, collapsed envelopes, and clear fragmentation. SARS-CoV-2 particles, initially measuring around 107 nanometers, were reduced to fragments of just 1.5 and 4.9 nanometers after ultrasound exposure, an unequivocal sign that the virus had disintegrated.

SARS-CoV-2 particles, initially measuring around 107 nanometers, were reduced to fragments of just 1.5 and 4.9 nanometers after ultrasound exposure, an unequivocal sign that the virus had disintegrated.

For H1N1, the destruction was even more extensive, with particles disappearing completely from the detection range. Crucially, throughout the process, scientists monitored the temperature and pH of the medium, confirming that neither parameter changed. This rules out indirect thermal or chemical effects as the mechanism of action for the ultrasound.

To confirm that the structural damage had biological consequences, researchers used the treated viral samples to infect cells in the laboratory. The infectivity of SARS-CoV-2 was markedly reduced, with significantly lower viral loads in cells exposed to the weakened virus.

The mechanism behind this phenomenon is called acoustic resonance. At specific frequencies, sound waves couple with the physical structure of the virus, causing its envelope to vibrate until it breaks. This process depends on the virus's size and shape, not its chemical composition.

The study's authors suggest this technology could serve as a complement to existing antiviral treatments, as damaging the viral envelope would enhance the action of drugs. They also propose exploring its application for disinfection in clinical environments, opening a range of possibilities.

The primary limitation is that all experiments were conducted in the laboratory, outside the human body. It remains unknown how this method would behave in living tissues or its effects on healthy cells within a real organism. Therefore, researchers recommend moving towards testing in animal models and organoids, structures that mimic human organs, to validate its safety and efficacy before considering direct clinical applications.