Storage mites allergy
Allergy to mites found in stored flour and grain.
About storage mites allergy
Storage mites are tiny mites, related to house dust mites, that live in stored dry foods and animal feed such as flour, grain, cereals, dried fruit and hay. They multiply in warm, humid storage conditions, and disturbing infested material releases their proteins into the air to be inhaled. In sensitised people, this triggers an IgE-mediated allergic reaction much like dust mite allergy. Storage mites are a recognised occupational allergen, particularly important for farmers, bakers, grain handlers and others who work with stored produce, and they can also occur in domestic pantries.
The usual presentation is allergic rhinitis, with sneezing, a runny or blocked nose and itchy, watering eyes when handling affected foods or feed. As with dust mite, there is a strong link with asthma, so exposure can bring cough, wheeze and chest tightness, and it can worsen eczema. In some people, eating heavily mite-contaminated flour has caused more marked reactions, sometimes called "pancake syndrome," though this is uncommon. Everyday symptoms are usually not life-threatening but can significantly affect people whose work involves regular exposure.
Reducing exposure helps: storing flour and dried foods in sealed containers, keeping storage areas cool and dry, discarding old or infested stock, and wearing a suitable mask when handling large quantities. Diagnosis uses skin-prick or specific-IgE tests, which can distinguish storage mite from house dust mite sensitivity. Treatment follows the usual ladder of antihistamines and steroid nasal sprays. See a GP if symptoms are persistent, work-limiting, or accompanied by wheeze.
Common triggers
- Storage mites and products containing it
Symptoms
- Sneezing and a runny or blocked nose
- Itchy, red or watery eyes
- Itchy throat, nose or ears
- Coughing or wheezing
- Worsening of asthma
Avoidance & management
- Reduce exposure to the trigger where possible
- Keep windows closed during high-exposure periods
- Use air filtration and wash bedding regularly
- Shower and change clothes after exposure
- Use prescribed antihistamines, nasal sprays or preventers
Sources & references
Allergy safety: what everyone should know
Mild-to-moderate reaction signs
- Itching, hives or a raised rash
- Swelling of lips, face or eyes
- Tingling mouth, sneezing, runny nose
- Stomach pain, nausea or vomiting
Anaphylaxis — call 999 (UK) or 112 (EU) immediately
- Difficult or noisy breathing, wheeze, persistent cough
- Swelling of the tongue or tightness in the throat
- Dizziness, collapse, pale and floppy (young children)
- Use an adrenaline auto-injector (e.g. EpiPen) at once if prescribed, then call an ambulance even if symptoms improve
Allergy or intolerance? A true allergy involves the immune system and can escalate quickly; an intolerance (e.g. lactose intolerance) is unpleasant but not life-threatening. The symptoms overlap, so self-diagnosis is unreliable.
Getting tested: home-testing kits based on IgG are not diagnostically valid. If you suspect an allergy, ask a GP for referral to an allergy clinic for skin-prick or specific-IgE testing and a supervised food challenge where appropriate.