COVID-19 Linked to Increased Allergy Risk in New Study

The Cliff News | 5 October 2026

The long-term health consequences of COVID-19 continue to be a focus of research, with a new study indicating a potential link between SARS-CoV-2 infection and an increased risk of developing six specific allergic conditions. The findings, published in the Annals of Allergy, Asthma & Immunology, examine the potential public health burden of these allergies in both children and adults.

Researchers from the University of Washington School of Medicine's Division of Pulmonary and Sleep Medicine conducted a retrospective cohort study involving individuals aged 1 to 64 years. Employing a 1:2 propensity-score matching method, the study assessed the association between COVID-19 infection and the subsequent development of allergic diseases over an 18-month period. The analysis revealed a notable connection between past COVID-19 infection and an elevated risk for several common allergic conditions.

Key Allergic Conditions Identified

The study identified six allergic conditions that showed a significant association with a previous COVID-19 infection. These include:

• Atopic dermatitis
• Asthma
• Food allergy
• Rhinoconjunctivitis
• Medication allergy
• Urticaria (hives)

Within a subgroup of active-duty personnel, asthma and rhinoconjunctivitis were found to be significantly linked to prior COVID-19 exposure. For children specifically, the association was observed across all listed allergic conditions except for food allergy, which did not show a statistically significant link in this demographic.

Interestingly, the research also touched upon socioeconomic factors, suggesting that a higher sponsor rank, used as an indicator of socioeconomic status, was associated with a minor protective effect against developing asthma. This nuanced finding adds another layer to understanding the complex interplay of various factors influencing health outcomes post-COVID-19.

Exploring the Potential Link to Allergies

The researchers emphasized that these findings underscore a potential public health concern, highlighting the importance of vigilance for allergic conditions following COVID-19 infection. Prompt identification and treatment of these conditions are crucial, they stated. The study’s results may point towards a connection between SARS-CoV-2 infection and what is known as type 2 inflammation, an immune pathway implicated in the development of numerous allergic diseases.

Further explanations from the research team suggest that SARS-CoV-2 infection can disrupt the immune system and affect multiple organs both during and after the illness. This observation is consistent with earlier pandemic-related phenomena such as multisystem inflammatory syndrome in children (MIS-C) and the emergence of long COVID, which can manifest with persistent symptoms like fatigue, cough, breathlessness, nasal congestion, runny nose, and skin rashes.

Factors Contributing to the Association

Dr. Alan Khadavi, an allergy and asthma specialist based in Los Angeles, outlined several potential mechanisms that could explain the observed association between COVID-19 and allergic diseases. These include:

• Changes In Type 2 Inflammation: SARS-CoV-2 might alter immune regulation, thereby promoting type 2 inflammation, which is a key factor in many allergic conditions.
• Mast Cell Activation: The virus could trigger the activation of mast cells, leading to the release of histamine and other inflammatory chemicals. This can result in symptoms such as itching, hives, nasal congestion, and wheezing.
• Respiratory Changes: Inflammation in the nasal passages, sinuses, and lungs following COVID-19 might increase the respiratory system's sensitivity to environmental allergens and irritants.
• Increased Indoor Exposure: Lifestyle changes during the pandemic, leading to more time spent indoors, could have increased exposure to common indoor allergens like dust mites, pet dander, mold, and cockroach allergens, as well as indoor air pollutants.

Impact on Existing Allergies and Future Research

Respiratory viruses are well-documented triggers for asthma exacerbations. Dr. Khadavi noted that COVID-19 could potentially exacerbate this risk, especially if immune system changes persist in some individuals post-infection. However, it is crucial to note that the study identified an association, not a direct causal relationship.

Due to its retrospective design, the study cannot definitively prove that COVID-19 directly causes allergic diseases or that type 2 inflammation is the sole underlying mechanism. Further research is warranted to explore these complex interactions and establish definitive causal links. Public health strategies may need to incorporate monitoring for allergic conditions in individuals who have recovered from COVID-19.