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What happens to the brain with long COVID?

When the COVID-19 pandemic hit, many people experienced a loss or change in their sense of smell and taste. This is known as parosmia and can last weeks or months for some patients who had COVID-19. On this episode of The Vaccine Show, we speak to Stanford University smell expert Dr. Zara Patel who says olfactory retraining (sniffing strong scents like citrus, cloves and eucalyptus) can help people recover their sense of smell and taste. We also hear from long Covid-19 sufferers who describe the distorted smells they experience and how they have managed to cope with these symptoms over time.

While the loss of smell was one of the earliest signs that someone had contracted COVID-19, it can linger for weeks, months and even years after symptoms have cleared up. This is called long Covid-19 or persistent COVID-19, and it can affect vaccinated and unvaccinated individuals equally. It is important to understand how this condition impacts a person’s quality of life and what can be done to improve the symptoms.

In a recent study published on the preprint server medRxiv, researchers followed a cohort of patients with polymerase chain reaction-positive COVID-19 who reported smell loss lasting more than 7 days. Over the course of a year, they performed repeated olfactory function evaluations. The results showed that olfactory impairments resolved for most patients, but the proportion of people who developed “long” long Covid-19 smell disorders was increasing. This was accompanied by an increase in symptoms that could negatively impact their lives, including parosmia and phantosmia.

Parosmia is a symptom of COVID that makes smells appear strange, unpleasant or not present. It can lead to a lack of appetite and may cause you to experience the smells of burning, trash or rotting food. It can also affect your ability to identify certain scents, such as coffee, flowers and perfume. It is more common in women and the elderly.

Phantom smells are similar to parosmia in that they make a person experience tastes or smells that don’t match up with the actual object or scent. These sensations can be described as a burning, metallic or pungent odor and may occur when eating, drinking, breathing or touching objects. This symptom can be very distressing and cause a great deal of discomfort and anxiety.

A third of long Covid-19 patients experienced this symptom and it was more prevalent in those who had persistent olfactory impairments. The study authors noted that this sensory upheaval is disruptive to a person’s daily life and has serious implications for health, nutrition, work and wellbeing. They cited the loss of normal smell and taste as a significant factor in lowering quality of life for some patients.

The good news is that while long Covid-19 is still a challenge for millions of patients, there are ways to improve the symptoms over time. Getting plenty of rest, practicing a healthy diet and drinking enough fluids can all make a difference. Additionally, stellate ganglion block (SGB) treatment can help restore the sense of smell and taste for those suffering from long Covid-19.

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