Outbreak of Occupational Dermatitis Associated With Pyemotes ventricosus
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Martyna Tomczyk-Socha1, Katarzyna Jedrzejewska-Jurga2, Joanna Limburska2
1Department of Ophthalmology, Wroclaw Medical University, Wroclaw, Poland.
Importance:
Although Pyemotes species have been known to cause dermatitis, recent reports are rare. During the past 30 years, only 3 outbreaks of dermatitis caused by Pyemotes ventricosus have been reported.
Objective:
To analyze the causative agent of skin changes in employees of a company that produced herbal medicines.
Design, Setting, And Participants:
This case series includes 18 patients (8 men, 10 women; mean age, 44 years) who contracted unusual dermatitis after an occupational exposure in July and August of 2012 while working for a company that produced herbal medicines. The patients were examined at the Lower Silesia Regional Centre of Occupational Medicine in Wroclaw, Poland.
Exposures:
Workers weighed and packed 1 part of the Helichrysum arenarium herb.
Main Outcomes And Measures:
We hypothesized the causative agent to be P ventricosus. An examination of the herbal specimens for ectoparasites confirmed the diagnosis.
Results:
Initially 16 employees developed pruritic skin changes. Skin lesions with pruritic vesicles on an erythematous base with surrounding swelling and edema were observed. Several employees also developed a flulike illness. After 44 days, 2 new employees presented with the same skin changes. The analysis of working conditions showed that the same part of the H arenarium herb was weighed and packed at that time.
Conclusions And Relevance:
We found that changing the time when the herbs were weighed and abandoning gas fumigation containing methyl bromide resulted in the recurrence of an almost forgotten disease.
Insights
An outbreak of Pyemotes ventricosus dermatitis occurred in herbal medicine workers. Modifying herb handling and pest control measures successfully resolved the rare occupational skin condition.
Area of Science:
- Occupational Medicine
- Dermatology
- Parasitology
Background:
- Pyemotes ventricosus (a mite) is a known cause of dermatitis, but recent reports are infrequent.
- Only three Pyemotes ventricosus dermatitis outbreaks have been documented in the last 30 years.
Observation:
- Eighteen employees producing herbal medicines developed pruritic skin lesions, vesicles, swelling, and a flulike illness.
- Exposure occurred while weighing and packing a specific part of the Helichrysum arenarium herb.
- The condition recurred after initial cases, indicating a persistent environmental trigger.
Findings:
- Parasitological examination of the implicated herb confirmed Pyemotes ventricosus as the causative agent.
- The outbreak was linked to specific work practices involving the Helichrysum arenarium herb.
- Adjusting the herb handling schedule and discontinuing methyl bromide fumigation led to the resolution of symptoms.
Implications:
- This study highlights the potential for Pyemotes ventricosus to cause occupational dermatitis in environments handling natural products.
- It underscores the importance of identifying and controlling environmental factors contributing to rare dermatological conditions.
- Revising work procedures and pest management strategies can effectively manage and prevent Pyemotes ventricosus infestations.
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