In winter, nasal symptoms and coughs are frequent. It has almost always been attributed to viral colds, or the flu if accompanied by general breakdown. But every time allergists diagnose more allergies in winter. What is the cause? How to know if our symptoms are allergic or infectious? And how not to confuse them with COVID-19? Let’s go by parts.
Allergy to pollen and mites
There is no doubt that climate change has altered temporal patterns of allergen sensitization. Insects have noticed this, such as the pine processionary, which has adapted its biological cycle to these changes, causing allergic conditions since the first months of the year, when it used to come down from the pines at the beginning of spring. We follow them with the European URTICLIM project.
As for pollen, there are species that pollinate in autumn and winter, including different weeds and, since November, cypress pollen, which causes respiratory symptoms that are mistaken for flu symptoms. They differ from them by the absence of fever. On All Saints’ Day there are people with symptoms due to their pollen and that of the chrysanthemum, flowers that we usually take to the graves of our loved ones.
Regarding indoor allergens (mites and animal epithelia), it is logical that when spending more time indoors due to the prevailing cold, exposure and symptoms increase. It is possible that the feed of our pets is contaminated by a warehouse mite, which in our area is Lepidoglyphus destructor. Fortunately, for the treatment of rhinitis and asthma caused by mites, there is specific immunotherapy (or vaccines against allergens) that are very effective.
Nor should we ignore the allergy to cold . There are congenital cold allergy pictures (the newborn suffers from it just after birth) and acquired. Both are diagnosed by placing an ice cube on the skin and checking the resulting wheal. Idiopathic cold urticaria (or of unknown cause) is the most common form, appears in young people, and lasts from 4 to 9 years. The stimulus that triggers it can be handling cold objects, low temperatures or being exposed to a freezing wind.
Autumn menu and allergens
In food allergy we can also identify a seasonal pattern. In summer, for example, allergies to fruits of the Rosaceae family predominate (peach, Paraguayan, apricot, cherry, plum …). Then, when autumn arrives, our body asks us to eat foods with high energy value. It is because, like certain plantigrades and animals capable of hibernating, we retain in the pineal gland of our brain capacities for hibernation, currently at rest, but possibly used by our ancestors to resist glaciations more than 20,000 years ago.
Among those foods that increase our energy reserves, nuts stand out, which are powerful allergens. For this reason, food allergies are more frequent at Christmas holidays, especially hazelnuts, almonds and walnuts.
On the other hand, supplements based on seeds from various plants such as chia, goji berries, or sesame and flax seeds have become fashionable lately, which are an important source of fiber but also of allergens. Among them the fearsome LTPs (lipid transporter proteins), natural antifungals that cause anaphylaxis.
Mushroom and mushroom season
To top it all, in autumn and winter edible mushrooms, other important allergens, also enter our diet. The first case described was allergy to mushrooms, followed by shiitake, chanterelle and boletus, clearly differentiated from their possible toxic effects. Pleurotus causes allergy not only by ingestion, but also by inhalation of its spores in growers of this fungus.
But not only the mushrooms we eat are important. Its spores are biological aerosols, like pollen, and play a vital role in the interactions between atmosphere, biosphere, climate, and public health. Airborne bacteria, fungal spores, pollen, and other bioparticles are essential for the reproduction and spread of organisms, with the downside that they can cause or amplify disease in humans, animals, and plants.
So much so that their interaction is implicated in serious pathologies such as asthma, stroke, ischemic heart disease and cancer. Fungi can be the cause of allergic respiratory disease, either of the upper or lower airways. Especially in sensitive people and from other allergy symptoms such as urticaria, dermatitis, pneumonitis and alveolitis.
Recent studies have shown that the prevalence of allergy to fungi is higher than previously thought and that fungi, as the cause of bronchial asthma and other diseases of the respiratory system, could have been underestimated. Fungal spores are found in the air at concentrations much higher than pollen, and in many cases they are smaller than pollen grains, thus being able to more easily reach the lower respiratory tract and cause asthma.
For years our group has focused on studying the allergenicity of fungi. Specifically, we have generated a robust database and a study at the molecular level to complete the air quality study carried out since 2006 by the aerobiological network of Castilla y León. We are based on information from 19,774 patients with allergic respiratory disease seen in our unit in the last 12 years. The objective was none other than to help specify the clinical diagnosis and subsequent treatment.
So far, the glycoprotein from the fungus Alternaria has proven to be the most allergenic molecule. Of course, in these cases the bronchial provocation test would not be indicated, considered gold standard for diagnosis but very risky. Molecular analysis was helpful in deciding a more precise and useful immunotherapy in curing affected patients.
How to know if it is allergy or COVID-19?
The confinement we have been subjected to highlighted the need to communicate clinically efficiently with our most vulnerable patients, who in our experience have been patients with difficult-to-control asthma and nursing home patients.
From our group, we developed a new early warning system for environmental risk and COVID-19 infection through a mobile tele-monitoring APK application that warns the vulnerable patient of any environmental event that may affect their health due to biological, chemical or microbiological contamination. of the atmosphere you breathe and sends immediate handling and treatment instructions.
We draw on clinical experience collected in 23,000 asthmatic patients from the HURH Allergy Unit database over the past 30 years, and on meteorological, biological and chemical contaminant data obtained from reliable sources. The aim was to offer an innovative system from a clinical and management point of view. This included a personalized and remote alert that would avoid as much as possible relapses and admissions produced by chemical and biological pollutants that are suspended in the air concurrently in patients more prone to respiratory failure. To help self-assess this vulnerable population if it has been infected by coronavirus and to know how to respond immediately. This complexity of features, it must be said, had not yet been developed by any application.
What seems indisputable is the usefulness of the clinical application of big data applied to health problems associated with climate change and possible future pandemics.
On the other hand, in addition to the patients under telematic follow-up in our Difficult Asthma Unit, a cohort of patients located in different nursing homes in the province of Valladolid was identified, with a relevant number of patients with COVID-19, as well as multiple pathological patients , which are an even more vulnerable segment of the population to suffer the negative consequences of the pandemic to a greater extent.
Introducing in the analysis all their clinical data (age, sex, comorbidities, fever, anosmia, desaturation, etc.) and taking a positive CRP as the “gold standard”, we were able to perform a multivariate analysis and a mathematical model that was specified in simple questions. to the app user. It is useful to elucidate if the respiratory symptoms are due to allergens, pollutants or COVID-19.
The health self-assessment obtained from our patients, together with aerobiological and air quality data, can be a useful and scalable instrument in the long term. It is a novel advance in environmental control with reliable objective data and would provide the opportunity to establish national and international “climate risk and pandemic study networks” that have already taken an interest. With this application, the target population will be able to receive quality, preventive and proactive care. Attention that guarantees at the same time the effectiveness, accessibility and safety of the patients and health workers who attend to them.
Does the mask help?
Good news for allergy sufferers is that the use of masks to minimize the spread of COVID-19 can help them with their illness. A study carried out by the SEAIC Committee of Experts in which the filtering power of protective masks against exposure to pollen and dust mites was analyzed concluded that the use of approved masks – which reduce particles by up to 80% of pollens and dust in the inhaled air – it is an effective tool to reduce allergic symptoms in patients.
“These masks have a high filtration capacity and reduce pollen and dust particles in inhaled air by up to 80%,” explained Dr. Ángel Moral, president of the Aerobiology Committee of the Spanish Society of Allergology and Clinical Immunology (SEAIC). By reducing symptoms, there is a decrease in the use of rescue medications and less attendance at emergency services.
Alicia Armentia Medina, Professor of Allergy. Department of Medicine. Head of the Allergy Department of the Río Hortega University Hospital, University of Valladolid
This article was originally published on The Conversation. Read the original.
