Milder, upper respiratory symptoms associated with new COVID-19 variants often mimic seasonal allergies, making it difficult to determine if a cough or nasal congestion is due to pollen or a viral infection. This overlap makes self-diagnosis challenging for the average person. This article aims to clarify the differences between the two conditions by examining their distinct symptom profiles.
Symptoms Shared by Allergies and COVID-19
Seasonal allergies and mild COVID-19 share several symptoms, including a stuffy or runny nose. Both conditions cause nasal congestion resulting from the body’s immune system initiating a defense response. A cough and a sore throat are also shared, though the underlying cause differs.
An allergic cough is typically an irritant cough triggered by postnasal drip, where excess mucus runs down the back of the throat. In COVID-19, a cough is usually a response to the viral infection in the respiratory tract. Fatigue and headaches are further symptoms that can overlap, complicating the distinction.
Allergy-related fatigue often stems from disrupted sleep due to nasal obstruction or the side effects of antihistamine medications. For viral infections like COVID-19, fatigue is a direct result of the immune system working to fight off the pathogen.
Unique Indicators for Differentiating the Conditions
One of the most reliable differentiators is the presence of a fever, which is a common sign of a viral infection, including COVID-19, but is not caused by allergies. If a temperature registers at 100.4°F or higher, the symptoms are almost certainly due to an infection and not an allergic response.
Allergies are often characterized by an intense itchiness that affects the eyes, nose, throat, or roof of the mouth. This symptom is a direct result of the immune system releasing histamine in response to an allergen, and it is rarely seen with COVID-19. Watery eyes are another hallmark of an allergic reaction.
The speed of symptom onset can also offer a clue, as COVID-19 symptoms tend to appear relatively acutely. Conversely, allergy symptoms often wax and wane depending on the level of environmental exposure to the trigger, such as pollen. A new and sudden loss of taste or smell, known as anosmia, is highly characteristic of COVID-19, even without significant nasal congestion.
COVID-19 can also cause systemic symptoms like severe muscle or body aches, which are uncommon with allergies. Furthermore, while allergies may cause mild symptoms that respond quickly to antihistamines, a lack of improvement after using standard allergy medication suggests a different underlying cause. Gastrointestinal issues like nausea, vomiting, or diarrhea are occasionally reported with COVID-19 but are not typical features of seasonal allergies.
Recommended Actions When Symptoms Appear
If symptoms emerge that could be either an allergy or COVID-19, taking a rapid at-home COVID-19 test is the most definitive step for clarification. If the test result is positive, self-isolation protocols should be followed immediately to prevent transmission of the virus to others. A negative result, especially if a fever is present or other viral symptoms persist, may warrant a retest within 48 hours or consultation with a healthcare provider.
Self-isolation is generally recommended while awaiting test results or if there is suspicion of a viral infection, especially following a known exposure. If symptoms worsen, or if an individual is at an increased risk for severe illness, consult a doctor for guidance on treatment and management. For those with a history of allergies, managing mild symptoms with usual medications is a reasonable first step if a fever is absent.