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Two Reports About the Havana Syndrome: Which Should We Believe?

Photo by Natasha Connell on Unsplash

Written by Brad Roth

In 2016, staff in the US embassy in Havana, Cuba reported a variety of medical symptoms, including ringing in the ears, fatigue, and dizziness. The condition suffered by these officials is now known as the Havana syndrome. Two government reports, one by an elite group of scientists called JASON [1] and the other by the National Academies of Sciences, Engineering, and Medicine [2] reached different conclusions about the most likely cause of the Havana syndrome. Which should we believe?

The JASON Report

In 2018, JASON­ conducted an investigation into the Havana syndrome. JASON was created soon after the Sputnik launch to provide technical advice related to defense. The group includes eminent scientists from many fields; several members have won the Nobel Prize. In September 2021, the news organization Buzzfeed obtained a redacted copy of JASON’s Havana syndrome report through the Freedom of Information Act. [3]

One claim of many people suffering from the Havana syndrome is that they heard strange sounds coinciding with the onset of symptoms. In their report, JASON examined cell phone recordings of these sounds. They were loud, but not so loud that they were painful; the victims didn’t cover their ears to block the noise. The sound didn’t seem to be localized to a beam, but did emanate from a specific location. The sound recorded by the phone was similar to that heard in person. WiFi and TV reception was not disrupted when the sound was present.

In their report, JASON concluded that “the recorded sounds are mechanical or biological in origin, rather than electronic. The most likely source is the Indies short-tailed cricket, Anurogryllus celerinictus.” After examining the frequency content of the recorded sounds, the report concluded that the call of these crickets matched the recordings “in nuanced detail.”

One possible cause of the Havana syndrome is that the embassy officials were attacked by directed microwave (radio frequency, RF) or acoustic weapons. However, JASON concluded that “the recorded audio signal is, with high confidence, not produced by the nonlinear detection of high power radiofrequency or ultrasound pulses.” Those arguing in support of a microwave weapon have suggested the Frey effect [4] (a mechanism by which microwaves produce acoustic waves inside the head, which are then detected by the inner ear) is responsible for the noises that victims heard. However, JASON judged as “unlikely the notion that pulsed RF mimics acoustic signals in both the brain (via the Frey effect) and in electronics (through RF interference pickup).” In other words, if the sound arises from the Frey effect, which occurs inside a person’s head, then the sound isn’t associated with an acoustic wave in the air. Cell phones wouldn’t record such sounds unless it was through electronic interference. But victims claimed that the sounds recorded on their cell phone were like those that they heard during the “attack.” It is highly improbable that sound arising from electronic interference would sound just like the noise heard via the Frey effect.

The National Academies Report

The Department of State asked the National Academies to review the evidence surrounding the Havana syndrome and make recommendations. The National Academies is a non-profit organization founded by Congress in 1863, charged with providing independent, objective advice to the nation on matters related to science and technology.

A 19-person committee chaired by David Relman, a Stanford microbiologist, prepared the National Academies report. It was published in 2020, and considered four possible explanations for the symdrome: chemical exposure, infectious disease, psychological issues, and directed pulsed radio frequency energy. The committee found no evidence for chemicals such as insecticides or for infectious agents such as the Zika virus. Those causes would affect not only the embassy diplomats, but also the local staff working at the embassy. Furthermore, it contended that the sudden onset of symptoms was not consistent with a psychological cause (a conclusion not held by everyone [5]). Because the sounds that victims heard seemed to be associated with a particular direction and location, the report suggested that radio frequency energy was the most plausible explanation for the symptoms. The committee did not seem to be aware of the JASON report, which was completed two years earlier but was classified and therefore not readily available.

The National Academies report noted that victims did not feel any warming, nor was there any thermal damage evident in medical images. It therefore excluded intense radio frequency energy that is associated with heating. The report next addressed nonthermal mechanisms associated with weak electromagnetic fields. At this point, it cited individual articles supporting nonthermal biological responses to radio frequency radiation. The scientific literature regarding the biological effects of electromagnetic waves is enormous and inconsistent. You can make arguments either for or against the biological effects of radio frequency radiation depending on which references you choose. The report did not cite many review articles or meta-analyses that critically assessed much of this research, nor did it address the lack of plausible biophysical mechanisms underlying radio frequency effects.

Instead, the report cited reviews of radiotherapy [6–8], despite its use of x-rays and other ionizing radiation, which is completely unlike the nonionizing radiation of radio frequencies and microwaves. It cited a discussion of microwave therapy applied through a catheter to destroy tissue [9], despite that being an obviously thermal effect. It cited microwave studies at very high frequencies [10] without noting that the electromagnetic skin depth would prevent these waves from penetrating into the body [11]. It cited the blood brain barrier work by Leif Salford [12] without mentioning that these results were inconsistent with other studies [13]. It cited a review of electromagnetic hypersensitivity [14], a phenomenon in which a person claims to be affected by weak electromagnetic fields, even though medical research suggests that electromagnetic hypersensitivity is not real [15]. It cited the coherent vibrations postulated by Herbert Fröhlich [16] without mentioning the theoretical limitations of such a mechanism [17]. Finally, when discussing voltage gated calcium channels, it cited two papers by Martin Pall [18,19], a researcher who promotes a relationship between 5G radiation and Covid-19 [20] and whose ideas about voltage gated calcium channels have been refuted [21].

Next the report considered the Frey effect [4], suggesting that it could explain why the victims of the Havana syndrome heard noises. It claimed that a “Frey-like” effect might induce responses similar to those created during transcranial magnetic stimulation to treat depression. Magnetic stimulation, however, is based on a well-understood mechanism: a strong rapidly changing magnetic field induces an electric field in the brain that is sufficient to excite neurons. The method uses pulses that last a tenth of a millisecond, corresponding to frequencies of about a ten kilohertz. This is a much lower frequency than the gigahertz signals presumably used by a microwave weapon. The report does not explain why there should be any connection between the Frey effect and transcranial magnetic stimulation, except that they both involve electric and magnetic fields.

In defense of the National Academies report, the committee had limited evidence to draw on, and the report did stress the tentative nature of its conclusions. Nevertheless, it took a less skeptical view of the scientific literature surrounding the biological consequences of radio frequency electromagnetic radiation than do many of those who have reviewed this subject, including myself. Many of the papers that the report cites are the same as those used to buttress claims that cell phones cause cancer, a claim which is not accepted by most of the scientific community, including the National Cancer Institute [22], the Centers for Disease Control and Prevention [23], and the Food and Drug Administration [24].

Who to Believe?

Which do we believe: the report by JASON or the one by the National Academies? Without further evidence (such as the detection of electromagnetic waves during an attack), I tend to agree with JASON: the Havana Syndrome is not caused by attacks using microwave weapons. To me, the National Academies report lost much of its credibility when it cited electromagnetic hypersensitivity as a real effect and when it cited the work of a 5G/Covid advocate. What were they thinking?



2. National Academies of Sciences, Engineering, and Medicine (2020) An Assessment of Illness in U.S. Government Employees and Their Families at Overseas Embassies. Washington, DC, The National Academies Press


4. Frey, A. H. (1962) Human auditory system response to modulated electromagnetic energy. Journal of Applied Physiology 17:689–692.

5. Baloh, R. W. and Bartholomew, R. E. (2020) Havana Syndrome: Mass Psychogenic Illness and the Real Story Behind the Embassy Mystery and Hysteria. Springer, Cham, Switzerland.

6. Citrin, D. E. (2017) Recent developments in radiotherapy. New England Journal of Medicine 377(22):2200–2201.

7. Mohan, G., Ayisha Hamna, T. P., Jijo, A. J., Saradha Devi, K. M., Narayanasamy, A. and Vellingiri, B. (2019) Recent advances in radiotherapy and its associated side effects in cancer — a review. The Journal of Basic and Applied Zoology 80:14.

8. Tsao, M. N., Xu, W., Wong, R. K., Lloyd, N., Laperriere, N., Sahgal, A., Rakovitch, E. and Chow, E. (2018) Whole brain radiotherapy for the treatment of newly diagnosed multiple brain metastases. Cochrane Database of Systematic Reviews 1:CD003869.

9. Saitz, T. R., Conlin, M. J., Tessier, C. D. and Hatch, T. R. (2019) The safety and efficacy of transurethral microwave therapy in high-risk catheter-dependent men. Turkish Journal of Urology 45:27–30.

10. Ramundo-Orlando, A. (2010) Effects of millimeter waves radiation on cell membrane — a brief review. Journal of Infrared, Millimeter, and Terahertz Waves 31:1400–1411.

11. Adair, E. R. (2002) Biological effects of radio-frequency/microwave radiation. IEEE Transactions on Microwave Theory and Techniques 50:953–962.

12. Salford, L. G., Brun, A. E., Eberhardt, J. L., Malmgren, L. and Persson, B. R. (2003) Nerve cell damage in mammalian brain after exposure to microwaves from GSM mobile phones. Environmental Health Perspectives 111:881–883.

13. Perrin, A., Cretallaz, C., Collin, A., Amourette, C. and Yardin, C. (2010) Effects of radiofrequency field on the blood-brain barrier: A systematic review from 2005 to 2009. Comptes Rendus Physique 11:602–612.

14. Stein, Y., and Udasin, I. G. (2020) Electromagnetic hypersensitivity (EHS, microwave syndrome) — review of mechanisms. Environmental Research 186:109445.

15. Rubin, G. J., Hillert, L., Nieto-Hernandez, R., van Rongen, E. and Oftedal, G. (2011) Do people with idiopathic environmental intolerance attributed to electromagnetic fields display physiological effects when exposed to electromagnetic fields? A systematic review of provocation studies. Bioelectromagnetics 32:593–609.

16. Fröhlich, H. (1988) Theoretical physics and biology. In Biological Coherence and Response to External Stimuli, edited by Fröhlich. H., Berlin, Germany: Springer-Verlag, 1–24.

17. Sheppard, A. R., Swicord, M. L. and Balzano, Q. (2008) Quantitative evaluations of mechanisms of radiofrequency interactions with biological molecules and processes. Health Physics 95:365–396.

18. Pall, M. L. (2013) Electromagnetic fields act via activation of voltage-gated calcium channels to produce beneficial or adverse effects. Journal of Cellular and Molecular Medicine 17:958–965.

19. Pall, M. L. (2016) Microwave frequency electromagnetic fields (EMFs) produce widespread neuropsychiatric effects including depression. Journal of Chemical Neuroanatomy 75(Pt B):43–51.


21. Wood, A. and Karipidis, K. (2021) Radiofrequency fields and calcium movements into and out of cells. Radiation Research 195:101–113.






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Brad Roth

Brad Roth

Professor of Physics at Oakland University and coauthor of the textbook Intermediate Physics for Medicine and Biology.