House dust mites – A menace beyond asthma

Guidelines were set

in 1994, UK’s Asthma Management Guidelines were set by medical opinion leaders as: (1) properly diagnosed, (2) avoidance of triggers (where possible) (3) selected treatment of choice, but there was no support for house dust mite avoidance, and allergy testing was considered of little value as a clinical investigation.¹ The new guidelines, distributed in the NHS demonstrated a disregard for past published research on the mite either as a risk factor for asthma or for the importance of skin prick testing to identify triggers.^2,3,4 Following the guidelines’ publication there was renewed research interest in asthma in universities or pharma labs focusing on the immune mechanisms of the condition, either at the molecular level or through genetic susceptibilities. The thrust of the research was to seek new treatments for asthma utilizing basic science.⁵
 

Guidelines have not changed

Thirty years later (2024), asthma guidelines have not altered in principle. What has altered is the treatment of drug choice with novel medication (some in combinations), immunotherapy, and biologics adding to the list of methods to alleviate symptoms, not cure asthma.,^6,7 While the investigations led to excellent treatments that are globally promoted what was left behind was asking why the house dust mite was a major cause of asthma, or crucially looking at the debris or potential pathogens, or bacteria the mite carries on, or in, its body or droppings., ^8,9 The debris can be made up from fungal, viral or bacterial origin that are not mite allergens, but from the dirt found in the mite’s environment.¹⁰ Some of the dirt presents potential risk to human health, such as Escherichia coli and Staphylococcus aureus.¹¹ Antibiotic resistant strains of Staphylococcus aureus (MRSA) are considered a global risk to public health.¹²
 

A gateway to something worse

Asthma patients sensitized to house dust mites may consider it safe to be exposed to mite allergens as long as their asthma is in control, but they remain largely unaware that the mite can present risks beyond asthma. Many human diseases, including cancer, have bacterial associations, or as an origin.^13,14 Here it is important to recognise that the major house dust mite allergen is a digestive enzyme that can breach respiratory cell defenses, thus offering an opening to the body for opportunistic bystanders.¹⁵
 

People need to be aware

The mechanisms to identify potential pathogens carried by mites are available and should be supported, expanded and broadcast.¹⁶ It is not safe to sleep with dust mites of any species. To prove the point, in an old mattress scientists found seven different species of mites, each with its own purpose, all making their own biological ‘dust’.¹⁷ The scientists who research mites in the field of medical entomology often find that their work is on file, shelved, or used as tools for future research, not disseminated to the wider public as health risks or used as educational platforms in schools.^2,18 The result is an unhealthy misalignment in public health messaging on the threat to health from mite exposure over treatments that dull mite related allergy symptoms.
 

It's time to challenge the past

Thirty years after the house dust mite was wrongly dismissed as a cause of asthma, medical research must now turn its focus by asking, how guilty are dust mites as carriers of human disease? That was the question asked in 1986 by Japanese doctors searching for the cause of Kawasaki disease.¹⁹ If they had the tools available to scientists today, perhaps their question could be answered.

Nell Nockles
May 1st 2024 ©
contact-nell [at] housedustmite dot com
See also: Asthma Missmanagement (2019)

References

1. ’Guidelines on the Management of Asthma’ Thorax 1993; 48, Supplement S1-S24 and British Medical Journal, 20th March 1993, Volume 306, page 776
2. 'Dust Mite Allergies and Asthma - A worldwide Problem', Platts Mills TAE, de Weck A, UCB Institute of Allergy, Bad Kreuznach September 1987. Reported in The Journal of Allergy and Clinical Immunology, 1989, 83, pages 416 to 42
3. Exposure to House Dust Mite Allergen (Der p1) and the Development of Asthma in Childhood. Sporik R, Holgate ST, Platts-Mills TAE, Cogswell JJ, New England Journal of Medicine, 1990; 323 (8): 502-507
4. An analysis of skin prick test reaction in 656 asthmatic patients. Hendrick DJ, Davies RJ, D’Souza MF, Pepys J, Thorax 1975; 30, 2-8.
5. ‘Molecular mechanisms of steroid action in asthma’, Professor P J Barnes, J. Allergy Clin. Immunol 1996, 97: 159-68 DOI: 10.1016/s0091-6749(96)80216-8
6. Asthma: diagnosis, monitoring and chronic asthma management. National Institute for Health and Care Excellence. NICE Guidelines (ng80, March 22, 2021, www.nice.org.uk/guidance/ng80
7. Global Initiative for Asthma (GINA) ginasthma.org/2023-gina-main-report/
8. ‘Bacterial 16S ribosomal DNA in house dust mite cultures’, Valerio Cherry R. Murray Patrick, Arlian Larry G, Slater Jay E, ‘J Allergy Clin Immunol’. 2005 Dec; 116(6): 1296-300 doi;10.1016/j.jaci.2005.09.046
9. ‘Assessment of bacterial communities in thirteen species of laboratory-cultured domestic mites (Acari: Acaridida)’, Jan Hubert, Jan Kopecky, Marketa Sagova-Mareckova: Marta Nesvorna; Ludek Zurek; Tomas Erban. J Econ. Entomol. (2016) 109 (4): 1887-1896
10. Studies of house dust mites can now fully embrace the “-omics” era. Geoffrey A. Stewart Ph.D, J Allergy Clin. Immunol. February 2015, p549-550
11. ‘House dust mites as potential carriers for IgE sensitization to bacterial antigens’, Dzoro S et al, ‘Allergy’, 2018; 73:115124. John Wiley & Sons. DOI 10.1111/all.13260
12. Jack Pepys Lecture, WAO/BSACI Conference, 2022, ‘Major Threats to Humanity and Nature of the World’, Professor Cezmi Akdis
13. Intracellular bacteria in cancer-prospects and debates, Lena Schorr, Marius Mathies, Eran Elinav, Jens Puschhol. Nature > npi Biofilms and Microbiomes, 9, No 76 (2023)
14. Bacterial and fungal microflora in surgically removed lung cancer samples. Apostolou, P et al. J. Cardiothorac. Surg. 6, 137 (2011)
15. Protease allergens as initiators-regulators of allergic inflammation, Soh et al, Allergy, 2023; 78:1148-1168
16. Comparative microbiome analysis of Dermatophagoides farinae, Dermatophagoides pteronyssinus, and Tyrophagus putrescentiae. Lee J, Kim JY, Yi MH, Hwang Y, Lee IY, Nam SH, et al . J Allergy Clin Immunol, 2019,143:1620-3. doi: 10.1016/j.jaci.2018.10.062
17. ‘An “in situ’ coring technique for estimating the population size of house dust mites in their natural habitat’, D. B. Hay, Acarologia, t. XXXVI fasc. 4, 1995
18. ‘Dust Mites’, Colloff M J, 2009 CSIRO Publishing, ISBN 978-0-6430-6589
19. Microorganisms associated with the house-dust mite ‘Dermatophagoides’, Heinan Oh, Akira Ishii, Yasumsa Tongu, Kazuo Itano, Department of Parasitology, Okayama University Medical School, Japan. 1986, Sanitary Zoology, 37, 229-235