Environmental allergies, which are now increased for most spring allergy sufferers, are characterized by dry cough, sneezing, runny nose, nasal congestion, and itchy red, runny eyes.  Asthma symptoms may also be escalated this time of year for those patients with allergic asthma that responds to environmental allergens like grass, tree, and weed pollen.  Symptoms of asthma are shortness of breath, wheezing, chest tightness, and sometimes cough.  These are similar to the COVID-19 symptoms.  So how do you distinguish?

In a study of 204 patients with COVID-19 admitted to hospitals between January 18th and February 28th, 50.5% presented with Gastrointestinal symptoms:  78.6% had lack of appetite, 34% had diarrhea, 17% had loose stools, 3.9% had vomiting and 2% had abdominal pain on presentation.  Almost 20% of patients had digestive symptoms without respiratory symptoms, while 83% of those with digestive symptoms also had respiratory symptoms.

 

In this same study, Fever was a symptom in 92.2 % of patients; weakness occurred in 52.4% of patients and muscle aches in 14.5% of patients.

Anosmia, or lack of smell, has also been a unique presenting symptom.  This is not unusual for a viral infection and was initially reported in a significant number of patients with proven COVID-19 in South Korea, China and Italy ().  Germany reported that two out of three cases of COVID-19 had ansomia and 30% of COVID-19 positive patients in South Korea also has anosmia.  Complete lack of smell is unusual with environmental allergies in absence of nasal polyps but this would be a chronic issue rather than have a sudden onset.

Summary:

  • Itching in general (of eyes, nose, skin, etc) is characteristic of allergies, not typically COVID-19
  • Fever is a characteristic of COVID-19 (or other infection), not allergies or asthma
  • Sudden loss of appetite, taste and smell are more likely to be COVID-19 than environmental allergies and asthma
  • While fatigue can be present in patients with uncontrolled allergies or asthma, when it is otherwise inexplicable or accompanied by muscle aches and fever, it may be indicative of COVID-19 or other viral infection

References:

  1. Pan, L. et al. Clinical Characteristics of COVID-19 Patients With Digestive Symptoms in Hubei, China: A Descriptive, Cross-Sectional, Multicenter Study J. Gastroenterol 2020 Mar 19. Link: https://journals.lww.com/ajg/Documents/COVID_Digestive_Symptoms_AJG_Preproof.pdf
  2. Kumar, N. Loss of sense of smell as marker of COVID-19 infection. ENTUK. Reviewed April 8. Link: https://www.entuk.org/sites/default/files/files/Loss%20of%20sense%20of%20smell%20as%20marker%20of%20COVID.pdf