Perspective Chapter: Management of Allergic Diseases during Pandemic

Abstract

Over the recent time period, pediatric allergy clinics across the world have markedly changed their practice because of the COVID-19 pandemic. Nowadays, clinics are not inclined to accept a patient demanding a new procedure / therapeutic modality during pandemic. All allergic diseases require continuous management and treatment, and their socioeconomic burden has been increasing worldwide. In this chapter, the aim is to focus on allergic diseases management during pandemic. During this time, patient follow-up, patient management, and diagnostic tests are real challenges. Limited face-to-face consultations and as much as use of telemedicine are currently seen as the major issues in the allergy practice. Face-to-face examination and treatment should be preferred only in vital situations. During COVID-19 pandemic, patient education, which is the most important step in the treatment of allergic diseases, has started to be done online. The prevailing opinion in the allergy community is that the treatment should not be interrupted, or dose reduction should not be made. According to the guidelines, it is appropriately recommended to carefully calculate the profit and loss of the treatment on a case-by-case basis.

1. Introduction

Throughout the World, admission to the hospital was restricted during the pandemic, except for emergencies. Over the recent time period, pediatric allergy clinics across the world have markedly changed their practice because of the COVID-19 pandemic. All allergic diseases require continuous management and treatment, and their socioeconomic burden has been increasing worldwide [1]. On top of it, the prevalence of allergic diseases has been dramatically increasing in the world [1]. In this chapter, the aim is to focus on the management of allergic disorders, disease by disease, during pandemic.

2. Allergic rhinitis

Allergic rhinitis is a very common disease that impairs quality of life if left untreated. Although the prevalence of allergic rhinitis is between 10% and 58,5% worldwide, it varies widely [2]. Allergic rhinitis is an immunoglobulin E (IgE) mediated allergic disease. Allergic patients manifest with symptoms of rhinitis and conjunctivitis, nasal itching, rhinorrhea, nasal congestion, cough, postnasal drip, and sneezing [3]. According to the guidelines, the diagnosis must be confirmed by a skin test and laboratory.

The allergic rhinitis treatment is composed of three major categories: environmental control measures or allergen avoidance, pharmacological treatment, and specific allergen immunotherapy.

Intranasal corticosteroid therapy for these patients can be questionable. But there is no evidence that such therapy can cause immunosuppression. Considering the frequency of hospitalization and mortality in allergic rhinitis patients, it has been observed that these allergic diseases do not pose a risk for COVID-19 [4]. Current therapy cessation is not recommended [3].

3. Anaphylaxis

The lifetime prevalence of anaphylaxis is estimated at 0,05–3% in USA and Europe [5]. Anaphylaxis is a potentially life-threatening, severe allergic reaction. The patient or medical doctor should not refrain from administering epinephrine as soon as they suspect anaphylaxis. During the pandemic, the average number of daily admissions to the emergency department has reported a significant drop. The severity of anaphylaxis symptoms is the main determinant of hospital admission. In particular, the number of food-related anaphylaxis may have decreased as a result of the closure of restaurants. The management of anaphylaxis during the pandemic, the most important point is to be able to immediately administer epinephrine. The use of epinephrine autoinjector as soon as possible is critical in reducing the severity of anaphylaxis symptoms. After that, patients should be monitored for treatment and symptoms (e.g., hypotension, wheezing, shortness of breath, vomiting, and swelling). Although applications to the emergency departments have decreased during the pandemic, it should not be delayed for a patient with anaphylaxis to present or be taken to the emergency department.

4. Asthma

Asthma is a chronic disease usually characterized by chronic reversible obstructive airway inflammation. The fluctuating clinical symptoms are shortness of breath, wheezing, chest tightness, and cough [3].

Asthma prevalence rates vary by country and by age [6]. During pandemic, performing spirometry and reversibility tests have been canceled in the beginning [7]. Later, various organizations formulated operational measures for resuming the functioning of pulmonary function test laboratories [8].

Asthmatic patients have to be managed carefully. T-helper 2 polarization might impair the efficient antiviral immune response [9, 10]. Asthmatic patients also have a greater susceptibility to respiratory viral infections, which may be a trigger for exacerbations [11, 12]. It is critically important to keep the disease under control in asthma patients [13, 14]. Discontinuation of therapy may exacerbate the underlying disease, which may adversely affect the clinic in patients infected with COVID-19. Many publications recommend that the inhaled steroid dose be maintained at the same dose. However, opinions have been presented that systemic (orally/parenterally administered) corticosteroid therapy could be risky [7].

According to the ARIA-EAACI statement, “If you stop or modify your treatment, you run the risk that your allergic disease, particularly your asthma control, could become worse, causing you to need rescue medications or be admitted to the hospital.” [5]. Continuation of anti-IgE (omalizumab) and other biological therapy (mepolizumab, enralizumab, etc.) is recommended during the follow-up of patients with severe asthma [15, 16].

In order to reduce the risk of SARS-CoV-2 transmission, it is preferred to treat the asthma attack at home with metered dose inhaler (MDI), and avoiding nebulizer treatment in the emergency services [7, 17].

When the COVID-19 pandemic emerged, concerns were also raised regarding the safety of allergen immunotherapy. Current studies demonstrated adherence by clinicians to national and international position papers and guidelines of allergen immunotherapy during the COVID-19 pandemic worldwide. Besides, several surveys/research have shown good tolerability of allergen immunotherapy for both subcutaneous and sublingual-oral forms [18].

Fortunately, the hospitalization frequency and time are not significantly increased in asthmatic patients more than in non-asthmatic patients since the pandemic asthma management becomes more complicated.

5. Atopic dermatitis

Atopic dermatitis prevalence is estimated up to 15–20% in the pediatric population and 1–3% in adults worldwide [19]. Focusing on atopic patients, the treatment plan (dosage, drug frequency) is not changed (not recommended to step down medication). It is also known that in patients with atopic dermatitis, the skin barrier is generally disrupted. For this reason, it is recommended to moisturize the skin frequently to avoid exacerbation of complaints.

There is no evidence that patients with barrier defects have a higher risk of SARS-CoV-2 infection or skin complications during COVID-19 [3]. Considering the frequency of hospitalization and mortality in atopic patients, it has been observed that these allergic diseases do not pose a risk for COVID-19. However, classic immunosuppressants or systemic glucocorticoids are not recommended in patients with severe atopic dermatitis due to broad immunosuppressive effects [3, 20, 21].

6. Food allergy

Food allergy can result in a life-threatening anaphylactic reaction. The prevalence of food allergy is generally higher in children than in adults, with a rate of 1–10% [22].

The visits of food-allergic children should be limited to those that are unequivocally needed on a clinical basis. During the pandemic, oral food challenges could be performed in just selected cases [23]. It is recommended to continue the current food diet. In preschool-aged children, accidental food allergic reactions were rarer. Since the food choice is made by the caregiver at preschool-aged, food allergy reaction is less common.

7. Urticaria- Angioedema

Roughly 15–23% of adults have experienced at least one acute urticaria episode at some time in their lifetime, and the prevalence of chronic urticaria in adults is estimated at 0,5–5% [24].

During the pandemic, the approach to urticaria patients differed from other allergic diseases. Because urticaria is one of the most common cutaneous manifestations of COVID-19. These patients were treated with oral antihistamines as well as oral steroids [25]. There was an increase in the frequency of admission to hospital with urticaria. There are many cases of urticaria associated with COVID-19 in the literature [12]. This situation should not be overlooked before the patient is evaluated as urticaria and treatment are started. Further evaluation and possible allergy tests and diagnostic procedures were canceled during pandemic. Only patients who needed hospital treatment that could not be postponed were hospitalized.

Immediate (type I) hypersensitivity reactions develop within 4–6 hours after COVID-19 vaccination and are mediated through Ig E-dependent mediator release. In the case of COVID-19 vaccines, polyethylene glycols and cross-reactive polysorbate 80 have been held responsible to be the triggering factors for immediate reactions. Type I reactions may range from mild, with urticaria-angioedema only, to life-threatening with anaphylaxis [26]. The most common reaction was urticaria followed by various skin rashes, that is, morbilliform, pityriasis rosea-like eruption, bullous drug reactions, fixed drug eruption, etc.

Acute urticaria only after any mRNA or CoronaVac vaccination should not be contraindicated for revaccination. Anaphylaxis to the first dose may be a contraindication to succeeding mRNA vaccination; however, various mild or nonimmediate allergic reactions are not. Type I allergic reactions after dose 1 of mRNA vaccine may contribute to unfinished vaccination. Allergists should be prepared to guide these kinds of subjects to preclude partial vaccination [27, 28].

Patients with urticaria were treated mainly with oral antihistamines. Oral steroids can also be used in therapy. Low-dose systemic steroids with antihistamines have been reported to effectively manage severe urticaria in patients [29]. Table 1 summarizes the approach to allergic diseases during the COVID-19 pandemic.

Allergic disease type	Treatment/follow-up recommendations
Allergic rhinitis	Intranasal corticosteroid cessation or interruption is not recommended [4, 5].
Anaphylaxis	The most dangerous life-threatening allergic disease is anaphylaxis and epinephrine administration is highly recommended as soon as anaphylaxis is suspected.
Asthma	Medication cessation may lead to asthma exacerbations [5, 13]. It is recommended to continue biologic therapy with anti-IgE or anti-IL-5 in patients with severe asthma [15, 16]. Many publications recommend that the inhaled steroid dose be maintained at the same dose. However, opinions have been presented that systemic (orally/parenterally administered) corticosteroid therapy is could be risky [8].
Atopic dermatitis	It is not recommended to step down medication [20, 21]. Frequent skin moistening is recommended.
Food allergy	It is recommended to continue the current food diet.
Urticaria - Angioedema	Urticarial patients were treated mainly with oral antihistamines. Oral steroids can also be used in therapy [25, 29].

Table 1.

Recently recommendations on allergic diseases.

8. COVID vaccine side effects in allergic diseases

Due to the “SARS-CoV-2” that started in 2019, there has been a challenging global pandemic process. One of the most effective public health interventions modern medicine has to offer is vaccination. No fatal cases have been reported in vaccine-related allergic reactions. According to a large population-based study, the frequency of vaccine-related allergic reactions is 1.31 (95%CI, 0.90–1.84) cases per million vaccine doses [30]. COVID-19 vaccines can cause a wide range of adverse effects from lymphadenopathy to pain at the injection site [31], but the allergic reaction mechanism, immediate or delayed, is unknown [32]. Side effects such as axillary tenderness, lymphadenopathy, nausea, vomiting, erythema/swelling/pain at the site of injection, fever, joint pain, chills, myalgia, headache, and fatigue are considered as mild reactions [31]. Both vaccines have rarely had serious side effects, including anaphylaxis. According to meta-analysis, the allergic reaction incidence is reported to be higher with the Moderna vaccine [31]. Besides, the excipients that are held responsible for allergic reactions are inactive ingredients that boost the immune response and prevent contamination [30]. Given the importance of the vaccine in fighting this public health crisis, understanding the allergic reactions to the US Food and Drug Administration (FDA) approved vaccines is pivotal [30]. On the other side, the Moderna vaccine has advantages over the Pfizer vaccine in terms of transport and storage [31].

Table 2 summarizes the COVID-19 vaccine’s properties and schedule.

	Pfizer/BioNTech vaccine	Moderna vaccine
Type	mRNA (BNT162b2)	mRNA (mRNA-1273)
Dose	Each dose contains 30 ug (0.3 mL)	Each dose contains 50 ug (0.5 mL)
Injection number/Period	2 shots, 21 days apart	2 shots, 28 days apart
Age group	6 months of age and older	6 months of age and older
Effectiveness	95% preventative	94.5% preventative
Mechanism of immunity	Into host cells to allow expression of the SARS-CoV-2 S antigen.	Into host cells to allow expression of the SARS-CoV-2 S antigen.

Table 2.

The COVID-19 mRNA vaccination schedule [31].

9. Conclusion

During pandemic, patient management, follow-up, and diagnostic tests are the real challenge. Limited face-to-face consultations and as much as the use of telemedicine is currently seen as the major issues in the allergy practice. Face-to-face examination and treatment should be preferred only in vital situations [33]. The treatment of allergic patients should not be interrupted, or dose reduction should not be made. According to the guidelines, it is recommended to carefully weigh the benefits and losses of the management on a case-by-case basis [34].