Blomia tropicalis
Summary
House dust mites (HDM) are the most important causes of allergic sensitization and diseases. Blomia tropicalis is one of the most prevalent species of HDM, found worldwide. It is predominantly found in tropical and subtropical regions and is known to coexist with Dermatophagoides pteronyssinus and/or Dermatophagoides farinae. Fecal particles of Blomia tropicalis HDM are considered as the major source of allergen carrier in air, that causes allergic reactions post-inhalation. Among the different allergens characterized for B. tropicalis, Blo t 1, Blo t 5 and Blo t 21 are the major allergens found. The most common clinical manifestations of B. tropicalis allergy, include allergic rhinitis, asthma, and atopic dermatitis. Allergens from B. tropicalis have been found to be cross-reactive to Dermatophagoides species and Tyrophagus putrescentiae. Cross-reactivity exists between Blo t 1 and Der p 1, Blo t 5 and Sui m 5 (Suidasia medanensis), Blo t 10 and Group 10 mites molecules, Blo t 21 and Tyr p 21, Blo t 13 and human fatty-acid binding proteins. Allergen immunotherapy and vaccines can be used as a treatment regime for patients with B. tropicalis allergy. Controlling the growth of dust mites, eliminating major reservoirs of dust mites, and maintaining proper hygiene is generally advised to prevent an allergic reaction to dust mites in sensitized individuals.
Epidemiology
Worldwide distribution
According to various evidence, an increase in the sensitization of B. tropicalis allergy has been reported, over the last few decades.
A retrospective study was conducted in Taiwan that involved 1145 patients with allergic sensitization and a history of receiving allergen-specific immunoglobulin E (IgE) tests. Based on the evaluation of allergic sensitization, it was found that the sensitization to B. tropicalis was found to be higher in older-age patients as compared to the younger ones (younger patients [3-6 years]: 15.1% vs. older patients [≥19 years]: 33.4%; p<0.001). Furthermore, the sensitization rate to B. tropicalis was more prevalent in coastal regions than in the city (coastal: 34.2% vs. city: 29.5%; p=0.091).
Large number of studies conducted in Singapore have identified 90-96% of atopic patients, being sensitized to HDMs, including B. tropicalis.
An International study was conducted to assess the prevalence of sensitization to B. tropicalis, among 297 asthmatic patients (including both adults and children), living in Latin American countries. The prevalence of sensitization to B. tropicalis was reported to be 47% in Mexico, while it was 93.7% in Brazil.
A study from Florida, USA, involving 167 patients with rhinitis and/or asthma, revealed that the prevalence of B. tropicalis was reported to be 38%, based on skin prick test (SPT). Furthermore, B. tropicalis was found to be a vital sensitizer, in a study conducted among 148 asthmatic patients from Cuba. It was reported that 85% of patients demonstrated a positive SPT to B. tropicalis.
A study was conducted that assessed sensitization to allergens among pediatric asthmatics (n=84; age range: 2-14 years), adult asthmatics (n=71; 16-80 years) and adult controls (n=71; age range: 20-61 years) in Thailand. The results revealed that the sensitization to B. tropicalis was found to be 9.5% in asthmatic children, 4.2% in adult asthmatics and 2.8% in healthy adults. Furthermore, co-sensitization to Dermatophagoides was observed in all children, sensitive to B. tropicalis.
A high level of specific IgE to two species of Blomia i.e. B. tropicalis and B. tjibodas has been documented in a study conducted in Germany, that involved farmers and city dwellers, sensitive to Blomia allergens.
Risk factors
Sensitization to B. tropicalis allergen can be a risk factor for the occurrence of allergic rhinitis (AR). Similarly, exposure to B. tropicalis has shown to cause aggravation of allergic symptoms in patients with atopic dermatitis (AD). Strong evidence has been reported regarding B. tropicalis, triggering the allergic nasal symptoms and inflammation of the mucosa in sensitized individuals.
Pediatric issues
Certain risk factors have been reported to cause aggravation of sensitivity to B. tropicalis in children. A cross-sectional study was conducted in 175 patients (mean age: 7.9 years) with sensitization to environmental allergens (including B. tropicalis) and subsequent clinical symptoms for at least 2 months. The results revealed that older age i.e., >5 years and breastfeeding <3 months were considered as the significant risk factors associated with sensitization to B. tropicalis (p<0.05).
Furthermore, Group 21 mite allergens, such as Blo t 21 (B. tropicalis) and Der p 21 (D. pteronyssinus) have reported a high frequency of sensitization in allergic children.
Route Of Exposure
Main
Airway inhalation is the main route of exposure to HDMs. The inhalation of mite fecal particles has reported eliciting allergic reactions in sensitized individuals. The mite fecal allergen, after being inhaled, reduces the mucociliary clearance, which in turn increases the deposition of inhaled particles, causing allergic sensitization.
Further, it has been reported that exposure of HDM allergen can act as a trigger in exacerbating the existing condition of asthma.
Secondary
In addition to inhalation (asthma, AR, eczema), mite allergens can trigger allergic symptoms in a sensitized person through additional routes, including ingestion (anaphylaxis, urticaria), and through direct contact (conjunctivitis, eczema).
Clinical Relevance
Mite-allergic patients with asthma might also have symptoms of AR. This supports the “unified airway” concept that asthma and AR may not be separate entities, but rather linked manifestations of allergic inflammation, occurring throughout the upper and lower airways.
A 13-month, multicenter survey reported HDM as the main cause of irritability, tiredness, disturbed sleep and troublesome professional life, in patients with severe/very severe burden of asthma and AR.
Allergic rhinitis
In a study conducted among 110 Brazilian adult patients with AR and/or asthma, 56.4% (n=62) showed positive SPT results to B. tropicalis. Among these, 67.7% reported positive IgE to B. tropicalis (42 out of 62). These results show the important role of B. tropicalis sensitization in patients suffering from AR. Interestingly, more than half of the patients found positive to B. tropicalis (>50%), were sensitized to major high-molecular weight allergens (54, 66, 68 kDa), as compared to low-molecular weight allergens (14 and 11-13 kDa components), found in other studies.
In a survey study, of 229 sera obtained from adult patients in Singapore, 124 were diagnosed as having persistent rhinitis. Among these patients, 73% were found positive to B. tropicalis allergens (91 out of 124), whereas 50% were positive to Blo t 5 allergens, specifically (62 out of 124). Furthermore, 43% (53 out of 124) and 36% (45 out of 124) of patients were found positive to Der p 1 and Der p 2 allergens, respectively. This showed that increased percentage of patients were found sensitized to Blo t 5, in comparison to Der p 1 and 2 allergens.
Asthma
Sensitization to HDMs is highly correlated with asthma. According to a study conducted, the nasal allergen challenge with B. tropicalis have reported to provoke allergic reactions and inflammation in the mucosa of sensitized subjects. Furthermore, its impact was observed in patients with existing asthma, wherein, the asthmatic symptoms were stimulated in the late phase.
In a cross-sectional study, involving 85 South-African children (age range: up to 18 years; 50 from KwaZulu-Natal [KZN] province and 35 from Johannesburg) with AR and/or asthma and positive SPT for aeroallergens, revealed that sensitization to B. tropicalis was found to be 52% in KZN and 2.9% in Johannesburg patients.
In another case-control study conducted in Brazil, 42 patients diagnosed with asthma (age range: 1-49 years) and 24 nonallergic patients (age range: 1-45 years) were identified. The results revealed that 83.3% of patients with asthma were found positive to B. tropicalis extracts on SPT, while only 12.5% of patients were sensitized to B. tropicalis in control group.
In a study conducted on 131 patients with asthma, 44% of patients were found sensitized to B. tropicalis.
Atopic dermatitis
The prevalence of sensitization to mites can be very high in patients with AD. The increase in the permeability of atopic skin and the ability of mite proteases to decrease skin barrier function, may allow more effective sensitization with aeroallergens, initiating a vicious cycle of inflammation and further allergen exposure.
In a case-control study, involving 36 AD patients (age range: 1- 49 years) and 25 nonallergic subjects (age range: 1-45 years), positive correlation was reported between AD patients and skin reactivity to B. tropicalis extracts (p <0.05). The study concluded that exposure to B. tropicalis can be considered as a risk factor in the development of AD.
In another case-control study conducted in Brazil, 34 patients diagnosed with AD (age range: 1-49 years) and 24 nonallergic patients (age range: 1-45 years) were identified. The results revealed that 61.7% of patients with AD were found positive to B. tropicalis extracts on SPT. Furthermore of 34 patients, 14 patients with AD and respiratory allergy reported 3.6-fold higher skin reactivity along with significantly greater IgE levels to B. tropicalis, as compared to 20 patients with AD alone.
Other diseases
Blo t 5 allergens have reportedly been found in several foods, such as wheat, rice, beans, corn, as well as in processed food items, such as pasta, pancakes, and rusk. Contamination of food items with Blo t 5 allergens can pose an increased risk of sensitization in individuals, due to long-term ingestion of infested food and exacerbation of symptoms in patients with an existing allergy.
In a case study identified, severe anaphylaxis was reported upon ingestion of pancake, contaminated with B. tropicalis allergens.
Prevention And Therapy
Allergen immunotherapy
Allergen specific immunotherapy has reported to be safe and effective immunotherapy, as per certain literatures.
In a double-blind, placebo-controlled, Phase II clinical trial conducted in Cuba, 35 asthmatic patients (age range: 16-45 years) were exposed and sensitized to B. tropicalis. According to the results, it was reported that subcutaneous AIT with standardized B. tropicalis extracts, was found to be both, safe as well as effective in these patients. In a study, hypoallergenic hybrid molecule of Blo t 5 and Blo t 21 was found to be a potential vaccine candidate for the treatment of allergic reactions caused by B. tropicalis.
Prevention strategies
Dust mites poorly thrive in extremely dry climates, and hence controlling the humidity can limit the growth of these mites. Exposure of HDMs can be prevented or reduced by wrapping the mattresses, pillows, and box springs in coverings, that are allergen-proof, washing the bedding with hot water in a week, cleaning the house, wearing an appropriate mask while cleaning, changing furnace and air-conditioner filters, and using a dehumidifier, that help in decreasing the humidity in homes. Furthermore, use of air-conditioning, freezing, heat treatment, harsh chemicals can be effective methods in minimizing the growth of dust mites.
In mite-sensitized asthmatic patients, bronchial hyperreactivity and bronchospasm was found to be aggravated, upon exposure to mites, however, the symptoms got improved in mite-free environment. Decreased exposure to mites can be useful technique in managing allergic patients, such as asthma.
Cross-Reactivity
The allergic sensitivity, following the ingestion of HDMs, show symptoms in two different forms - the ingestion of invertebrates demonstrating cross-reactivity with mite allergens, and the ingestion of foods that are contaminated with dust mites.
A high degree of cross-reactivity is noted between Dermatophagoides pteronyssinus and Dermatophagoides farinae extracts, however, the reactivity between Dermatophagoides and Blomia tropicalis is low.
In a study, co-sensitization and cross-reactivity had been reported between B. tropicalis and two Dermatophagoides species, i.e. Der p and Der f. In this study, 70.14% of allergenic patients (1050 out of 1497 patients) were found to be co‐sensitized to B. tropicalis, Der p, and Der f. However, the cross-reactivity between B. tropicalis and the other mites was limited.
A moderate degree of cross-reactivity has been shown between B. tropicalis and D. pteronyssinus, using inhibition assays. From sera of 12 allergic Venezuelan patients, 5 reacted to extracts of both mite species, while 4 reacted to only D. pteronyssinus and only 3 to B. tropicalis. In 2 of the 5 sera reactive to both mite species, it was seen that D. pteronyssinus could inhibit the binding of B. tropicalis, and vice-versa.
Amino acid sequence similarity of 30-50% has been reported between Blo t 1, Blo t 2 and Blo t 5, and Der p 1, Der p 2 and Der p 5 (D. pteronyssinus), hence suggesting low-to-moderate cross-reactivity between D. pteronyssinus and B. tropicalis.
Furthermore, between Blo t 3 and Der p 3, limited cross-reactivity has been reported. Blo t 3 showed a 54.8% amino acid sequence similarity with Der p 3 (trypsin-like serine protease) allergen in D. pteronyssinus. Blo t 11 has shown 90% similarity with Der f 11 (D. farinae) and 89% with Der p 11 (D. pteronyssinus). Blo t 13 demonstrated moderate-to-high cross-reactivity with human fatty acid binding-proteins (FABPS). Furthermore, Blo t 21 shares close to 40% of sequence homology with Blo t 5, however despite the similarities, Blo t 5 and Blo t 21 do not cross-react.
Marked cross-reactivity has been noted between Sui m 5 (from Suidasia medanensis) and Blo t 5.
Tropomyosin from B. tropicalis has demonstrated 95% homology with allergens from Group 10 mites. The Blo t 10 showed high homology with tropomyosin from Lepidoglyphus destructor (Lep d 10), D. pteronyssinus (Der p 10) and D. farinae (Der f 10).
Tropomyosin is a large family of heat-resistant, alpha-helical proteins. These proteins form a coiled-coil structure of two parallel helices, that includes two sets of seven alternating actin-binding sites. This feature plays a vital role in regulating the function of actin filaments.
One of the main important causes of cross-reactivity, among mites, shellfish, helminths, and cockroaches is the tropomyosin, although, glutathione transferase may also be included. In cases where genuine sensitization is unclear, specific allergen components can be useful to identify the primary allergy.
Tropomyosin allergens from HDMs are reported to show cross-reactivity with tropomyosin allergens of invertebrates, such as crustaceans (shrimp, lobster, crab, crayfish), mollusks (mussel, oyster, scallop, clams, abalone, snails, squid, octopus, cuttlefish) and insects (cockroaches).
Tyr p 5 (from Tyrophagus putrescentiae) showed 52.9% amino acid identity with Blo t 5. It also exhibited a 55.8% identity with Tyr p 21 and Blo t 21. Der f 21 was inhibited by both, group 5 and group 21 allergens (Tyr p 5, Tyr p 21, Blo t 5 and Blo t 21), reflecting cross-reactivity between the three.
References
- Miller JD. The Role of Dust Mites in Allergy. Clin Rev Allergy Immunol. 2019;57(3):312-29.
- Lahiani S, Dumez ME, Khemili S, Bitam I, Gilis D, Galleni M. Cross-Reactivity between Major IgE Epitopes of Family 5 Allergens from Dermatophagoides pteronyssinus and Blomia tropicalis. Int Arch Allergy Immunol. 2019;178(1):10-8.
- Santos da Silva E, Asam C, Lackner P, Hofer H, Wallner M, Silva Pinheiro C, et al. Allergens of Blomia tropicalis: An Overview of Recombinant Molecules. Int Arch Allergy Immunol. 2017;172(4):203-14.
- Yi FC, Shek LP, Cheong N, Chua KY, Lee BW. Molecular cloning of Blomia tropicalis allergens--a major source of dust mite allergens in the tropics and subtropics. Inflamm Allergy Drug Targets. 2006;5(4):261-6.
- Roden AE. Extraction efficiency and identification guide to common house dust and storage mites: University of Georgia; 2012.
- Caraballo L, Zakzuk J, Lee BW, Acevedo N, Soh JY, Sanchez-Borges M, et al. Particularities of allergy in the Tropics. World Allergy Organ J. 2016;9:20.
- NCBI. Blomia tropicalis Taxonomy ID: 40697 2020 [19-11-2020]. Available from: https://www.ncbi.nlm.nih.gov/Taxonomy/Browser/wwwtax.cgi?id=40697.
- Sanchez-Borges M, Fernandez-Caldas E, Thomas WR, Chapman MD, Lee BW, Caraballo L, et al. International consensus (ICON) on: clinical consequences of mite hypersensitivity, a global problem. World Allergy Organ J. 2017;10(1):14.
- Portnoy J, Miller JD, Williams PB, Chew GL, Miller JD, Zaitoun F, et al. Environmental assessment and exposure control of dust mites: a practice parameter. Ann Allergy Asthma Immunol. 2013;111(6):465-507.
- Gao YF, Wang de Y, Ong TC, Tay SL, Yap KH, Chew FT. Identification and characterization of a novel allergen from Blomia tropicalis: Blo t 21. J Allergy Clin Immunol. 2007;120(1):105-12.
- Yong SB, Wu CC, Tzeng YC, Hung WC, Yang KD. Different profiles of allergen sensitization in different ages and geographic areas in Changhua, Taiwan. J Microbiol Immunol Infect. 2013;46(4):295-301.
- Fernandez-Caldas E, Lockey RF. Blomia tropicalis, a mite whose time has come. Allergy. 2004;59(11):1161-4.
- Stanaland BE, Fernandez-Caldas E, Jacinto CM, Trudeau WL, Lockey RF. Sensitization to Blomia tropicalis: skin test and cross-reactivity studies. J Allergy Clin Immunol. 1994;94(3 Pt 1):452-7.
- Ferrandiz R. Sensitization to Dermatophagoides siboney, Blomia tropicalis, and other domestic mites in asthmatic patients. Allergy 1996;51(7):501-5.
- Daengsuwan T, Lee BW, Visitsuntorn N, Charoenratanakul S, Ruangrak S, Jirapongsananuruk O, et al. Allergen sensitization to aeroallergens including Blomia tropicalis among adult and childhood asthmatics in Thailand. Asian Pac J Allergy Immunol. 2003;21(4):199-204.
- Musken H, Fernandez-Caldas E, Maranon F, Franz JT, Masuch G, Bergmann KC. In vivo and in vitro sensitization to domestic mites in German urban and rural allergic patients. J Investig Allergol Clin Immunol. 2002;12(3):177-81.
- Pires MC, Calux MJ, Mori JC, Montealegre F. Reactivity of anti-Blomia tropicalis IgG and IgE in patients with atopic dermatitis. Clin Exp Dermatol. 2002;27(4):309-13.
- Wang DY, Goh DY, Ho AK, Chew FT, Yeoh KH, Lee BW. The upper and lower airway responses to nasal challenge with house-dust mite Blomia tropicalis. Allergy. 2003;58(1):78-82.
- Kidon MI, Chiang WC, Liew WK, Lim SH, See Y, Goh A, et al. Sensitization to dust mites in children with allergic rhinitis in Singapore: does it matter if you scratch while you sneeze? Clin Exp Allergy. 2005;35(4):434-40.
- Thomas Platts-Mills LC. DUST MITE ALLERGY B04. USING MOLECULAR ALLERGOLOGY IN THE CLINICAL PRACTICE. P M. Matricardi, J. Kleine-Tebbe. EACCI MOLECULAR ALLERGOLOGY USER’S GUIDE. 2016:105-13.
- Hussein AH, Elawamy W. Quantitation of Blomia tropicalis allergen Blo t 5 in cereal and cereal-based foods consumed in the Nile Delta, Egypt. Am J Trop Med Hyg. 2015;93(1):194-7.
- Thomas WR. Geography of house dust mite allergens. Asian Pac J Allergy Immunol. 2010;28(4):211-24.
- Baratawidjaja IR, Baratawidjaja PP, Darwis A, Yi FC, Chew FT, Lee BW, et al. Mites in Jakarta homes. Allergy. 1998;53(12):1226-7.
- Bennett WD, Herbst M, Alexis NE, Zeman KL, Wu J, Hernandez ML, et al. Effect of inhaled dust mite allergen on regional particle deposition and mucociliary clearance in allergic asthmatics. Clin Exp Allergy. 2011;41(12):1719-28.
- Marple BF. Allergic rhinitis and inflammatory airway disease: interactions within the unified airspace. Am J Rhinol Allergy. 2010;24(4):249-54.
- Demoly. The disease burden in patients with respiratory allergies induced by house dust mites: a year-long observational survey in three European countries. . Clin Transl Allergy 10, 27 (2020) https://doiorg/101186/s13601-020-00331-0. 2020.
- Pereira EA, Silva DA, Cunha-Junior JP, Almeida KC, Alves R, Sung SJ, et al. IgE, IgG1, and IgG4 antibody responses to Blomia tropicalis in atopic patients. Allergy. 2005;60(3):401-6.
- Yeoh SM, Kuo IC, Wang DY, Liam CK, Sam CK, De Bruyne JA, et al. Sensitization profiles of Malaysian and Singaporean subjects to allergens from Dermatophagoides pteronyssinus and Blomia tropicalis. Int Arch Allergy Immunol. 2003;132(3):215-20.
- Jeevarathnum AC, van Niekerk A, Green RJ, Becker P, Masekela R. Prevalence of Blomia tropicalis allergy in two regions of South Africa. S Afr Med J. 2015;105(7):567-9.
- Mori JC, Pires MC, Galvao CE, Ferreira de Mello J, Golcher FM, Montealegre F. Determination of Blomia tropicalis-specific IgE and IgG subclasses in atopic dermatitis patients. Allergy. 2001;56(2):180-4.
- Tsai JJ, Yi FC, Chua KY, Liu YH, Lee BW, Cheong N. Identification of the major allergenic components in Blomia tropicalis and the relevance of the specific IgE in asthmatic patients. Ann Allergy Asthma Immunol. 2003;91(5):485-9.
- Pino OMBd. First Report of Anaphylactic Shock Caused by the Ingestion of Mite-Infested Flour in Panama. World Allergy Organ J 2012 Feb; 5(Suppl 2): S104. 2012.
- Castro-Almarales RL, Ronquillo-Diaz M, Alvarez-Castello M, Rodriguez-Canosa J, Gonzalez-Leon M, Enriquez-Dominguez I, et al. Subcutaneous allergen immunotherapy for asthma: A randomized, double-blind, placebo-controlled study with a standardized Blomia tropicalis vaccine. World Allergy Organ J. 2020;13(4):100098.
- da Silva ES, Aglas L, Pinheiro CS, de Andrade Belitardo EMM, Silveira EF, Huber S, et al. A hybrid of two major Blomia tropicalis allergens as an allergy vaccine candidate. Clin Exp Allergy. 2020;50(7):835-47.
- van der Heide S, De Monchy JG, De Vries K, Dubois AE, Kauffman HF. Seasonal differences in airway hyperresponsiveness in asthmatic patients: relationship with allergen exposure and sensitization to house dust mites. Clin Exp Allergy. 1997;27(6):627-33.
- He Y, Dou C, Su Y, Chen J, Zhang Z, Zhao Z, et al. Identification of Der f 23 as a new major allergen of Dermatophagoides farinae. Mol Med Rep. 2019;20(2):1270-8.
- WHO/IUIS. Allergen Nomenclature- Blomia tropicalis (Storage mite) 2019 [20-11-2020]. Available from: http://www.allergen.org/search.php?Species=Blomia%20tropicalis.
- Mora C, Flores I, Montealegre F, Diaz A. Cloning and expression of Blo t 1, a novel allergen from the dust mite Blomia tropicalis, homologous to cysteine proteases. Clin Exp Allergy. 2003;33(1):28-34.
- Cheong N, Soon SC, Ramos JD, Kuo IC, Kolatkar PR, Lee BW, et al. Lack of human IgE cross-reactivity between mite allergens Blo t 1 and Der p 1. Allergy. 2003;58(9):912-20.
- Kuo IC, Cheong N, Trakultivakorn M, Lee BW, Chua KY. An extensive study of human IgE cross-reactivity of Blo t 5 and Der p 5. J Allergy Clin Immunol. 2003;111(3):603-9.
- Yi FC, Cheong N, Shek LP, Wang DY, Chua KY, Lee BW. Identification of shared and unique immunoglobulin E epitopes of the highly conserved tropomyosins in Blomia tropicalis and Dermatophagoides pteronyssinus. Clin Exp Allergy. 2002;32(8):1203-10.
- Ramos JD, Cheong N, Lee BW, Chua KY. cDNA cloning and expression of Blo t 11, the Blomia tropicalis allergen homologous to paramyosin. Int Arch Allergy Immunol. 2001;126(4):286-93.
- S. Vrtala SK, and J. Kleine-Tebbe. Chapter 22. Allergens, Diagnostics, and Therapeutic Aspects in House Dust Mite Allergy. J Kleine-Tebbe, T Jakob (eds), Molecular Allergy Diagnostics Springer International Publishing Switzerland 2017. 2017:415-28.
- Liu. Co‐sensitization and cross‐reactivity of Blomia tropicalis with two Dermatophagoides species in Guangzhou, China. Journal of Clinical Laboratory Analysis 33 101002/jcla22981 2019.
- Munera M, Martinez D, Labrada A, Caraballo L, Puerta L. Identification of B Cell Epitopes of Blo t 13 Allergen and Cross-Reactivity with Human Adipocytes and Heart Fatty Acid Binding Proteins. Int J Mol Sci. 2019;20(24).
- Popescu FD. Cross-reactivity between aeroallergens and food allergens. World J Methodol. 2015;5(2):31-50.
- Kim CR, Jeong KY, Yi MH, Kim HP, Shin HJ, Yong TS. Crossreactivity between group-5 and -21 mite allergens from Dermatophagoides farinae, Tyrophagus putrescentiae and Blomia tropicalis. Mol Med Rep. 2015;12(4):5467-74.