A mild, irritating sensation in the throat often prompts concern about a potential infection. Many people wonder if an itchy or scratchy throat might be an early sign of COVID-19. While this discomfort is associated with various common ailments, it can indeed be one of the first indications that the SARS-CoV-2 virus has begun its infectious process.
Prevalence of Itchy Throat in COVID-19
An itchy or scratchy throat is a recognized symptom of COVID-19, especially with the newer Omicron lineage and its subvariants. These variants often concentrate symptoms in the upper respiratory tract, making throat discomfort a highly prevalent complaint. Studies show that a sore throat was reported by over 70% of individuals infected with the Omicron variant, a higher frequency than earlier strains like Delta.
This shift means the infection frequently mimics common cold symptoms, rather than the classic presentation of a persistent cough or loss of taste and smell. Throat symptoms, whether itchy, scratchy, or sore, tend to appear early in the disease course. This early onset can occur within just a few days of exposure, which is a faster incubation period than the original SARS-CoV-2 strains.
The symptom of a scratchy throat is considered part of the broader category of pharyngeal symptoms, which are now characteristic of current COVID-19 infections. This places throat discomfort high on the list of symptoms reported by those who test positive. This high prevalence is a notable change from the initial phases of the pandemic, when fever and respiratory distress were the most frequent symptoms.
The Biological Mechanism Behind Throat Discomfort
The discomfort felt in the throat results from the virus targeting specific cells within the upper respiratory system. SARS-CoV-2 gains entry into human cells by binding to Angiotensin-Converting Enzyme 2 (ACE2) receptors found on the cell surface. Cells lining the nose and throat possess these ACE2 receptors, making them primary targets for viral replication, especially for variants preferring the upper airway.
The sensation is caused by the body’s localized immune response to the infection, not the virus itself. When the immune system detects the virus, it triggers an inflammatory reaction known as pharyngitis. This inflammation involves a rush of immune cells and fluid to the area, leading to irritation and swelling of the throat’s mucosal lining.
This localized fight against the virus is what manifests as the scratchy or itchy feeling, often prompting the need to cough or clear the throat. The immune system is trying to contain the infection at the entry point. The inflammatory process is a protective measure, although it is the source of the temporary discomfort.
Distinguishing COVID-19 from Other Respiratory Illnesses
Differentiating a COVID-19-related itchy throat from one caused by a common cold or seasonal allergies is difficult, but accompanying symptoms offer clues. Seasonal allergies often cause generalized itching, including the eyes, nose, and inner ear, which is less typical of COVID-19. Allergies rarely cause a fever, whereas fever or body aches are frequently associated with COVID-19.
The presence of sneezing is another point of differentiation, as it is a usual and prominent symptom of both allergies and the common cold. While sneezing can occur with COVID-19, it is not as characteristic as it is with other upper respiratory conditions. The speed of symptom onset is also relevant; COVID-19 symptoms appear rapidly, while allergy symptoms tend to be chronic or persist for weeks during a season.
The only reliable way to distinguish the cause of throat discomfort is through diagnostic testing. Since newer COVID-19 variants present with symptoms that overlap significantly with other respiratory illnesses, symptom-based differentiation alone is unreliable. A positive result from a rapid antigen test or a PCR test remains the definitive method for confirming a SARS-CoV-2 infection.