For the past week, Ricardo and I have been dealing with breakthrough COVID infections. It’s affected us in different ways. While Ricardo lost his sense of smell (anosmia), he’s retained taste. I initially kept smell but lost taste. Now, both senses are gone for me but I can still detect chemically triggered sensations such as spiciness (chemesthesis). We did that test on me yesterday with some Tabasco sauce: three drops on a piece of fried potato. I couldn’t taste anything but immediately my taste buds “lit up” with a spreading sensation of spiciness. It was fascinating.
Viral-induced smell loss existed long before COVID-19. But the percentage of people experiencing smell dysfunction and loss is much higher with this virus than with other types of infections. While the mechanisms are not fully understood, there is an emerging consensus that smell loss occurs when the coronavirus infects cells (known as sustentacular cells) that support neurons in the nose.
Research from Harvard Medical School has found that SARS-CoV-2 attacks by targeting certain receptors on the surfaces of cells.
Sustentacular cells have many such receptors while olfactory sensory neurons do not. This suggests that the coronavirus infects the support cells, which then leaves the neurons vulnerable and damaged. As recovery from COVID-19 begins, cells regenerate and make new functional neurons, allowing most people to regain their sense of smell after a few weeks. Not everyone recovers, unfortunately and this requires intervention. This can come in the form of steroids and smell conditioning, an olfactory equivalent of physical therapy that works through repeated exposure to essential oils with different scents, in order to relearn them.
Did the vaccines work? Absolutely. They did what they were supposed to do – keep us out of the hospital and from dying. Our bodies are fighting a new threat – why face that without protective armor? Stack the odds in your favor – eat healthy, exercise, get vaccinated (and if vaccinated, get a booster if possible). Wear masks and practice social distancing.
Photo: U. Horodyskyj