One of the more unusual symptoms of COVID-19 is the loss of one’s sense of smell and taste. If this has happened to you, you will definitely recall: Waking up one morning and discovering that your cup of coffee is no longer as bitter as it once was.
If you were feeling adventurous, you could have tried dousing dishes in hot sauce for a little tingle or biting into a lemon or lime for a subtle acidity during your seclusion. The novelty would wear off eventually, and you’d simply hope your sense of smell would return.
Many respiratory illnesses impair a person’s sense of smell by inflaming the nasal cavity, resulting in sniffles, stuffy noses, and difficulty smelling. SARS-CoV-2, on the other hand, takes its interference to a new level by infiltrating supporting cells in the nose and crossing the wires that connect the nose and brain.
That sounds pretty terrifying, and that side effect may reveal the course of your infection and recovery. Columbia University researchers released a study in PLoS ONE on Wednesday that connected chemosensory disturbance (loss of smell or taste) following a COVID infection to a person’s immunological response to the virus, the remains of which can stay in their bloodstream for months.
They evaluated the antibody levels of 306 persons who gave convalescent plasma in the spring of 2020 after a self-reported COVID-19 infection.
They discovered that persons who lost their sense of smell or taste were rough twice as likely as those who didn’t to have high levels of IgG antibodies. These antibodies indicate an immune response and have been demonstrated to increase when a person recovers from a COVID-19 infection as well as after vaccination.
Higher IgG antibody levels aren’t inherently better or worse than lesser ones, but the researchers noticed that high antibody levels are indicative of a severe COVID-19 infection.
The patients sampled all reported a COVID-19 infection in early 2020, and a fresh study has shown that the rates of smell and taste loss are lower with newer COVID versions. Because the study participants were not followed over time, it is impossible to know how these high antibody levels affected them, either in terms of the durability of their symptoms or following re-exposure to the virus.
Some persons who lose their sense of smell or taste after contracting COVID-19 require months or longer to regain them; further research is needed to know why this happens and how to restore these senses to patients.
Still, the new findings add another layer to our ongoing efforts to grasp what COVID infection means in the long run, especially as reinfection rates continue to rise.