Allergy to Artemisia
Artemisia allergy is a form of summer hay fever that is less common than other pollen allergies, but is clinically significant due to two distinctive features: its frequent overlap with ragweed pollen, which can prolong and complicate the allergy season in multisensitised individuals, and its frequent association with reactions to spices, vegetables and aromatic foods.
What is Artemisia and where does it grow?
Artemisia (genus Artemisia, family Asteraceae) is a perennial aromatic herb, extremely common throughout Italy, found along roadsides, in meadows, along watercourses and on nitrogen-rich fallow land. The species of greatest allergological significance is Artemisia vulgaris (wild wormwood or common artemisia), which is widespread in lowland and hilly areas across the whole country.
Its wide geographical distribution and ability to grow in man-made environments such as roadside verges, derelict land and gardens make it a very common allergen to which people are exposed during the summer months, even for those who do not spend time in natural environments.
Artemisia belongs to the same botanical family as ragweed (Asteraceae): this relationship underlies partial pollen cross-reactivity between the two allergens, which requires specific measures to distinguish between sensitisation to them at the diagnostic level.
[Weber RW. Mugwort, A. vulgaris. Ann Allergy Asthma Immunol. 2006;97(2):A4.]
Pollen season: when symptoms appear
Artemisia allergy is a summer hay fever: symptoms appear during the warmer months, in a period that partially overlaps with the ragweed season, with which it shares allergenic characteristics and a similar pollen calendar.
- Start of flowering: July
- Pollen peak: August – September
- End of the season: October in warmer areas
Artemisia produces large quantities of light pollen, which is easily carried by the wind even over considerable distances. The highest pollen concentrations are recorded on hot, dry and windy days, typically during the middle of the day.
In individuals sensitised to both Artemisia and ragweed – a common condition resulting from either genuine sensitisation to the two pollens or cross-reactivity – the overall allergy season can extend from July to late October, with a particularly significant cumulative impact on quality of life.
[Ariano R. & Bonifazi F. Aerobiologia ed allergeni stagionali. Editore ECIG, 2006]
Prevalence of sensitisation
Sensitisation to Artemisia pollen is less common than other major pollinoses such as those caused by grasses and birch: it generally affects fewer than 10 per cent of people with pollen allergies in European populations. However, in certain geographical areas – particularly r in regions of northern Italy where Artemisia and ragweed coexist – the prevalence may be higher. [G D'Amato et al. Allergenic pollen and pollen allergy in Europe. Allergy. 2007 Sep;62(9):976-90]
Sensitisation to Artemisia is often associated with polysensitisation, both genuine and cross-reactive, to other pollen allergens. In polysensitised patients, molecular allergy testing is particularly useful for identifying the primary sensitisation and guiding treatment decisions.
Molecular allergens of Artemisia
The main allergen in Artemisia vulgaris is Art v 1, a protein found in high concentrations in pollen, which is responsible for the vast majority of allergic reactions to the plant. It is considered the reference molecular marker for primary sensitisation to Artemisia. Other allergens, such as Art v 3, Art v 4 and Art v 6, are responsible for cross-reactivity with ragweed. The presence of certain ‘pan-allergens’ also accounts for cross-reactivity with other pollens and foods.
[N. Wopfner, G. et al. The Spectrum of Allergens in Ragweed and Mugwort Pollen. Int. Arch. Allergy Immunol. 138 (2005) 337–346.
Symptoms of Artemisia allergy
Symptoms appear during the summer pollen season and may affect the upper airways, the eyes and, in susceptible individuals, the lower airways. Their severity is related to the concentration of pollen in the environment and can vary significantly from one day to the next.
Nasal symptoms
- Repeated sneezing
- Nasal itching
- Watery nasal discharge
- Nasal congestion
Eye symptoms
- Red eyes
- Itchy and burning eyes
- Excessive tearing
Bronchial symptoms
- Dry cough
- Wheezing
- Dyspnoea (shortness of breath)
- Chest tightness
In patients with pre-existing bronchial asthma, the Artemisia season – particularly in cases of co-sensitisation to Ambrosia – may represent a period of increased risk to disease stability, requiring active and planned therapeutic management.
Cross-reactivity: Artemisia, ragweed and foods
Cross-reactivity is one of the most characteristic and clinically significant aspects of Artemisia allergy. Cross-reactivity involves both other pollens and numerous foods, with a risk profile that varies depending on the molecular allergens involved.
Cross-reactivity with other pollens
The most significant bidirectional cross-reactivity is that with ragweed pollen, which belongs to the same botanical family (Asteraceae), where Art v 6 and Amb a 1 play a significant role, but sometimes also Art v 1 and Amb a 4. Patients sensitised to Artemisia may also experience symptoms in response to exposure to ragweed pollen, and vice versa. The diagnostic picture is often made even more complex by cross-reactivity linked to ‘pan-allergens’ and carbohydrate determinants. This overlap can make it difficult to clinically identify which of the two plants is the primary source of sensitisation without resorting to molecular diagnostics.
[Asero et al. Concomitant sensitization to ragweed and mugwort pollen: who is who in clinical allergy? Ann Allergy Asthma Immunol. 2014 Sep;113(3):307-13.]
Cross-reactivity with foods
One of the most distinctive features of Artemisia allergy is its recognised association with reactions to certain foods. The so-called Artemisia-celery-spice syndrome is characterised by allergic reactions to certain foods from the Apiaceae family, such as celery, carrots, parsley, fennel, aniseed, coriander, dill, cumin and other aromatic spices, in individuals sensitised to Artemisia.
Traditionally attributed to cross-reactivity between ‘pan-allergens’ and PR-10 proteins, with subtle symptoms (as in the case of birch oral allergy syndrome), more recently the role of proteins that are more stable to heat and digestion has been highlighted, as these are responsible for systemic and more severe reactions. These include molecules such as Art v 3, Art v 1, Art v 60 kDa and their respective homologues—LTPs, defensins and FAD-containing oxidases—found in food.
This means that, in some individuals, reactions may occur not only with raw foods but also with cooked or processed foods, and may involve not only the oral cavity but also the gastrointestinal tract or other systems.
[M. Egger, et al. Pollen-food syndromes associated with weed pollinosis: an update from the molecular point of view Allergy 61 (2006) 461–476.
Popescu FD. Cross-reactivity between aeroallergens and food allergens. World J Methodol. 2015;5(2):31-50.
Other foods associated with cross-reactivity
Cross-reactions have also been reported with foods belonging to the Asteraceae family (such as chamomile and sunflower), with mustard, lychee, and occasionally honey, although with lower frequency and clinical significance compared with the foods involved in the celery-mugwort-spice syndrome.
The presence of cross-reactivity does not necessarily imply the onset of clinical symptoms in all sensitised individuals: clinical significance, individual risk profile and any dietary restrictions must be assessed on a case-by-case basis by an allergy specialist, including through molecular diagnostics.
Impact on quality of life
Although Artemisia allergy is less common than other pollen allergies, it can have a significant impact on the quality of life of those affected during the summer months. The food- l implications associated with cross-reactivity can add a further layer of complexity to day-to-day management.
The most significant consequences for the patient include:
- Respiratory and ocular symptoms during the summer and autumn seasons
- Sleep disturbances caused by symptoms during peak pollen weeks
- Reduced ability to concentrate and impaired performance at work or school
- Restrictions on dietary habits due to cross-reactions with spices and vegetables
- A prolonged allergy season in individuals with multiple sensitivities to ragweed
- Worsening of asthma in patients with bronchial comorbidities
Reducing exposure: practical measures
Reducing exposure to Artemisia pollen follows the same general principles as for other summer pollinoses. As it is a very common plant in urban and peri-urban areas, it is difficult to avoid exposure completely, but certain measures can help to limit it during periods of high pollen concentration.
- Monitor regional pollen forecasts and limit outdoor activities on days when pollen concentrations in the air are high
- Avoid going outdoors during the middle of the day, when pollen concentrations are at their highest
- Keep windows closed during pollen peaks and use air conditioning fitted with suitable filters
- Take a shower and change your clothes after being outdoors
- Wear wraparound sunglasses to reduce contact between pollen and the mucous membranes of the eyes
- Avoid areas near meadows and uncultivated land where mugwort is abundant, particularly during the summer peak
Exposure-reduction measures are intended for information purposes and should be regarded as complementary to drug therapy and any immunotherapy, as part of a treatment plan agreed with your doctor.
Frequently Asked Questions
Artemisia and ragweed belong to the same botanical family (Asteraceae) and have a partially overlapping pollen season (July–October). Cross-reactivity between the two pollens is common, to the extent that many patients are sensitised to both. The clinical distinction between primary sensitisation to Artemisia and to Ambrosia requires an allergy assessment to identify the specific allergens (Art v 1 for Artemisia, Amb a 1 for Ambrosia).
Yes. In the absence of appropriate treatment, allergic rhinitis caused by Artemisia can progress to involve the lower airways (bronchial asthma), in line with the ‘allergic march’ phenomenon. In multisensitised individuals, the progressive expansion of sensitisation may also broaden the profile of food cross-reactivity. Early diagnosis and an active treatment plan are essential.
Yes. Allergen-specific immunotherapy (AIT) using Artemisia extracts is a treatment capable of modifying the patient’s immune response, reducing sensitisation and the long-term progression of the disease. Some studies have also documented a reduction in food cross-reactions following immunotherapy with Artemisia. Suitability for treatment must be assessed by an allergy specialist, taking into account the patient’s molecular profile.
It is advisable to consult a doctor if you experience nasal, ocular or bronchial symptoms that occur regularly in summer, or if you have reactions to celery, carrots, spices or other aromatic foods. An allergy assessment involving skin prick tests and, where indicated, molecular diagnostics, allows the diagnosis to be confirmed, the sensitisation profile to be defined and the treatment plan best suited to the patient’s individual characteristics to be established.
Practical insights
Information notice
The information contained on this page is for informational purposes only and is not a substitute for the advice of a doctor or other qualified healthcare professionals. For a clinical assessment and any treatment decisions, including the choice and management of drug therapies and allergen-specific immunotherapy, you should consult your specialist doctor. The practical guidance provided is intended as complementary measures to support exposure management, as part of an individualised treatment plan.