RELATED: This Is How Long Your Omicron Symptoms Will Last, Doctors Say. The latest research comes from a team of scientists in Sweden looking to better understand one of the most bizarre and highlighted symptoms of COVID-19 infection: anosmia, or loss of smell. In a preprint study that has not been peer-reviewed, the researchers ran tests on 100 patients who had been infected with COVID during one of the earliest waves in Sweden in the spring of 2020. Results showed that while only four percent of those sampled ever lost their sense of smell entirely, 33 percent of them had experienced a decreased ability to sense odors, and 49 percent of patients reported parosmia, which is the medical term for a distorted sense of smell, The Guardian reports. The team also ran the same tests on a control group of participants who tested negative for COVID antibodies, finding that one in five people showed lessened senses of smell, which shows how common smell disorders can be in the general population. Ultimately, the researchers concluded that 65 percent of patients who eventually recovered from COVID-19 still suffered a complete loss, reduction, or significant change in their sense of smell 18 months after they initially caught the virus. Comparatively, only 20 percent of people who have never had COVID suffer any deficiency in their ability to smell. The researchers point out that participants involved in the study were volunteer healthcare workers who were more likely to be tested for the virus early on in the pandemic. As such, everyone was infected by the earliest version of COVID-19, predating the variants that eventually evolved and changed some aspects of how the virus behaves. It also means that no one in the group had yet been vaccinated.ae0fcc31ae342fd3a1346ebb1f342fcb However, the researchers ultimately concluded that “given the amount of time since [the] initial insult to the olfactory system, it is likely that these olfactory problems are permanent.”

RELATED: For more up-to-date information, sign up for our daily newsletter. While studies established partial or total loss of smell to be relatively common during the early phases of the pandemic, some research has found that the latest version of the virus may not be likely to cause the same symptom. According to a study from the U.K. Health Security Agency, anosmia or parosmia were less than half as likely to be reported when infected with the currently dominant Omicron variant compared to the previous Delta variant. However, the authors of the Swedish study cited a lack of reliable data on Omicron’s ability to affect someone’s sense of smell and argue there’s still a possibility someone who’s infected could develop the symptom during the current surges, The Guardian reports. According to Johan Lundströmm, PhD, the initial study’s leader from the Karolinska Institute in Stockholm, long-term anosmia or parosmia can significantly affect a person’s overall health more than one might expect. “When you cannot smell, all you can sense is the five basic taste qualities, tactile sensations, and spices,” he said. “Unconsciously, people start to add more sugar and fat, or have an increased urge for fried food for the texture, all to get some enjoyment out of eating.” Even though the researchers say the long duration of the symptom is the most surprising finding from the study, Lundström explained that those whose sense of smell was affected can still see some improvement. “Many of these individuals can get help by doing olfactory training,” he told The Guardian. “They might not regain 100 percent of past performance, but most of them will, with training, get back to a point where their reduced sense of smell will not affect their lives.” RELATED: If You’re Over 40, This One COVID Symptom Might Never Go Away.