Short report: The potential of PCR on skin flakes from bed linens for diagnosis of scabies in an outbreak.

BACKGROUND: Scabies outbreaks are common in nursing homes in the Netherlands. In October 2018, a local public health service (PHS) in The Hague was notified of a new scabies outbreak in a nursing home in that region. The PHS initiated an outbreak investigation. Cases were defined as: possible (reported symptoms), probable (scabies-like lesions) and confirmed (PCR or microscopy in skin flakes). Head-to-toe examinations were performed of all residents and those staff members who reported symptoms suggestive of scabies. Skin scrapings of lesions were tested either with microscopy or by PCR. Experimentally for case finding, skin flakes from bed linens of residents who reported symptoms of itchiness but did not have primary lesions were sent for PCR testing. PRINCIPAL FINDINGS: All residents (41) and 37/44 staff were included in this outbreak investigation. We identified 30 possible, four probable and six confirmed cases. The overall attack rate for probable/confirmed cases was 10/78 (13%). Of the six confirmed cases, two were confirmed by PCR, three by microscopy, and one showed positive findings with both techniques. Two out of the three bed-linen specimens were PCR-positive. CONCLUSIONS: In this outbreak of scabies in a nursing home, PCR was used on skin flakes from bed linens, which led to the detection of two additional cases. This illustrates the potential of PCR during the investigation of scabies outbreaks.

A nosocomial scabies outbreak originating from immunocompromised transplant patients in Turkey: Upholstery as a possible cause.

BACKGROUND: Inpatients with crusted scabies represent an important source of nosocomial transmission with consequent outbreaks among patients and healthcare workers. This study aimed to report the course of an institutional scabies outbreak, which progressed with infestation of immunosuppressed transplant patients, health care workers, and caregivers. METHODS: Patients diagnosed with scabies in a nosocomial outbreak in a 200-bed, tertiary hospital were included. Following a diagnosis of scabies in the index patient, strict contact isolation measures were implemented. During the outbreak, a root cause analysis (RCA) was carried out by an infection prevention and control team. RESULTS: Forty-two individuals were affected (7 patients, 25 health care workers, and 10 family members of the patients) during the outbreak consisting of three attacks. Index case was a multiple myeloma patient who received hematopoietic stem cell transplantation and presented with crusted scabies. A RCA suggested that upholstery could serve as a means of reservoir. All upholstery of the sofa and armchairs in patient rooms as well as in lounge areas were replaced by wipeable leather material. After the 19-week course of the outbreak, no additional cases of scabies have been observed until now. CONCLUSION: A high index of suspicion should be maintained, particularly in immunocompromised patients, in order to achieve rapid diagnosis of scabies and to implement institutional infection control measures. It should also be borne in mind that the transmission may occur through direct contact as well as fomites, such as upholstery.

Identification of Bartonella rochalimae in Guinea Pigs (Cavia porcellus) and Fleas Collected from Rural Peruvian Households.

In the present study, we tested 391 fleas collected from guinea pigs (Cavia porcellus) (241 Pulex species, 110 Ctenocephalides felis, and 40 Tiamastus cavicola) and 194 fleas collected from human bedding and clothing (142 Pulex species, 43 C. felis, five T. cavicola, and four Ctenocephalides canis) for the presence of Bartonella DNA. We also tested 83 blood spots collected on Flinders Technology Associates (FTA) cards from guinea pigs inhabiting 338 Peruvian households. Bartonella DNA was detected in 81 (20.7%) of 391 guinea pig fleas, in five (2.6%) of 194 human fleas, and in 16 (19.3%) of 83 guinea pig blood spots. Among identified Bartonella species, B. rochalimae was the most prevalent in fleas (89.5%) and the only species found in the blood spots from guinea pigs. Other Bartonella species detected in fleas included B. henselae (3.5%), B. clarridgeiae (2.3%), and an undescribed Bartonella species (4.7%). Our results demonstrated a high prevalence of zoonotic B. rochalimae in households in rural areas where the research was conducted and suggested a potential role of guinea pigs as a reservoir of this bacterium.

[Human skin infestation caused by Haemolaelaps casalis: a case report].

Our study reports a case of acarodermatitis caused by Haemolaelaps casalis. By morphological observations, the mites seized were identified as Haemolaelaps casalis (deutonymph) which could attack humans resulting in acarodermatitis characterized with the symptoms of papules and blisters in different degrees. The patient was treated with 15% calamine lotion and anti-inflammatory and antipruritic drugs. Meanwhile, the mites were eliminated in the bedroom. After the treatment for one week, the patient was cured. Haemolaelaps casalis, which had been found in the indoor mattress, could attack humans and cause acarodermatitis. We should strengthen the work of anti-mite in domestic environment.

Assessing the efficacy of a novel temperature and humidity control machine to minimize house dust mite allergen exposure and clinical symptoms in allergic rhinitis children sensitized to dust mites: a pilot study.

BACKGROUND: House dust mite avoidance is advised in dust mite sensitized patients to decrease the risk to develop allergic symptoms. Maintaining a relative humidity (RH) of less than 50% in households is recommended to prevent dust mite proliferation. OBJECTIVE: To investigate the efficacy of a novel temperature and humidity machine to control the level of dust mite allergens and total nasal symptom score (TNSS) in dust mite sensitized allergic rhinitis children. METHOD: Children (8-15 years) with dust mite sensitized persistent allergic rhinitis (AR) were enrolled. The temperature and humidity control machine was installed in the bedroom where the enrolled children stayed for 6 months. TNSS was assessed before and every month after machine set up and the level of dust mite allergen (Der p 1 and Der f 1) from the mattress were measured before and every 2 months after machine set up using enzyme-linked immunosorbent assay (ELISA). RESULTS: A total of 7 children were enrolled. Noticeable reduction of Der f 1 was observed as early as 2 months after installing the machine, but proper significant differences appeared 4 months after and remained low until the end of the experiment (p <0.05). Although no correlation was observed between TNSS and the level of dust mite allergens, there was a significant reduction in TNSS at 2 and 4 months (p <0.05) and 70% of the patients were able to stop using their intranasal corticosteroids by the end of the experiment. CONCLUSIONS: The level of house dust mite in mattresses was significantly reduced after using the temperature and humidity control machine. This machine may be used as an effective tool to control clinical symptoms of dust mite sensitized AR children.

Bed bug dermatitis, description of two cases in Rio de Janeiro, Brazil.

Bed bugs are hematophagous insects which due to their morphological and biological characteristics are able to easily adapt themselves to human households. The authors describe two cases of dermatitis caused by bed bug bites in the city of Rio de Janeiro, Brazil. Patients presented linear lesions in the usual "breakfast, lunch and dinner" arrangement, suggesting this diagnosis. A visit to their dwellings showed infestation of insects identified as Cimex hemipterus. The knowledge of these insects by the dermatological community will contribute to an accurate diagnosis as well as subsidize the dissemination of information aiming for prevention.

Bed bug dermatitis, description of two cases in Rio de Janeiro, Brazil

Bed bugs are hematophagous insects which due to their morphological and biological characteristics are able to easily adapt themselves to human households. The authors describe two cases of dermatitis caused by bed bug bites in the city of Rio de Janeiro, Brazil. Patients presented linear lesions in the usual "breakfast, lunch and dinner" arrangement, suggesting this diagnosis. A visit to their dwellings showed infestation of insects identified as Cimex hemipterus. The knowledge of these insects by the dermatological community will contribute to an accurate diagnosis as well as subsidize the dissemination of information aiming for prevention.

[The worldwide expansion of bed bugs also constitutes a problem in Germany]. / Die weltweite Ausbreitung von Bettwanzen stellt auch in Deutschland ein Problem dar.

Worldwide, reports of the spread of the bed bugs Cimex lectularius and C. hemipterus (in Australia) are increasing. Irrespective of hygiene conditions, the insects can be especially found in hotels and hostels as well as in other holiday accommodation, health facilities, transport and in the secondhand trade. From these localities the insects spread to private households. A bed bug infestation may well have health consequences and constitutes a heavy burden for those affected. The global spread of bed bugs appears to be multifactorially conditioned and the causes are controversially discussed. The spread could be explained, among other things, by the increase in international travel and trade in used goods. The limited availability of insecticides with long-term effects and the development of resistance to available agents could play a crucial role. In the absence of official data it is impossible to quantify the extent of the spread in Germany but pest controllers and public authorities report increasing numbers of cases and problems in control. As in other countries the latter appear to be caused among other things by the development of drug resistance (particularly pyrethroids). Against this background, prevention and thus the education of the public on the habits and dissemination routes of these insects remain crucial in order to counteract the spread of bed bugs.

Distribution features of biological hazardous pollutants in residential environments in Korea.

This research has been conducted continuously since 2009 as part of a cohort of studies examining relationships between asthma and genetic factors, dietary habits, and environmental factors. Based on data from environmental research on house dust mites and endotoxins, which are widely known as pollutants in bedding that cause asthma in pregnant women and children, this work was conducted to obtain basic data that can be used in future cohort studies that analyze links between distribution of biological hazards and physical features of residential environments. The detection rates of house dust mite allergens, Der p1 and Der f1, were 52.7 and 86.5%, respectively, indicating that Der f1 is a dominant species in domestic indoor environments. According to comparisons between concentrations of house dust mites and endotoxins in bedding of pregnant women and children, Der p1 and endotoxins showed significantly lower concentrations in bedding of pregnant women compared with those in bedding of children, whereas Der f1 showed no significant difference in concentration according to bedding.

Infestation by pyrethroids resistant bed bugs in the suburb of Paris, France.

Bed bugs are hematophagous insects responsible for a re-emerging and challenging indoor pest in many countries. Bed bugs infestations may have health consequences including nuisance biting, cutaneous and systemic reactions. This resurgence can probably be attributed to factors such as increased international travel and development of resistance against insecticides. Resistance against pyrethroids has been reported several times from the USA and rarely in Europe. In France, very few data on bed bugs are available. The present study aimed to assess the infestation by bed bugs of a complex of two high-rise apartment buildings in the suburb of Paris and to evaluate their susceptibility to pyrethroid insecticides. We inspected for bed bugs 192 out of 198 apartments units (97%) and interviewed their residents. 76 (39.6%) apartments were infested. Among the 97 residents living in infested apartments, 53 (54.6%) reported bed bug bites. A total of 564 bed bugs were collected in the infested units. Bioassays showed that 54 out of 143 bed bugs were resistant to pyrethroids (37.8%; 95% confidence interval: 29.9-45.7%). DNA sequencing showed that all bed bugs tested (n=124) had homozygous L925I kdr-like gene mutation. The level of pyrethroid resistance found indicates that this phenomenon was already established in the site and prompts the need to reevaluate the wide use of pyrethroids to control bed bugs.

Bed bugs in healthcare settings.

Infestations caused by bed bugs have resurfaced during the past decade across all continents. Even though bed bugs primarily cause skin manifestations in humans, a major stigma is placed upon people or institutions found to carry them. It is important for healthcare facilities to be prepared for this pest by implementing policies, carefully selecting materials used for hospital furniture, and educating providers on early identification and control.

Mite exposure in a Spanish Mediterranean region.

BACKGROUND: Knowledge of the domestic mite fauna and allergen levels is important for a correct diagnosis and treatment of mite allergy. Our objectives were to describe the domestic mite fauna in the region of Murcia, Spain, to quantify mite allergens in dust samples obtained from mattresses of this area and to assess the influence of geographical, climatic and dwelling factors. METHODS: Dust samples were collected in a transversal descriptive study from mattresses of 51 patients who went to the Allergology Service, and from mattress of 81 neighbours or family members of these patients. A questionnaire about home environment was filled in and obtained by all participants. Mite identification was done by light microscopy and allergen determinations (Der p 1 and Der f 1) by monoclonal antibodies. RESULTS: Sixteen mite species were identified in the 132 dust samples collected. The most frequent species were Dermatophagoides farinae (36% of the samples), Dermatophagoides pteronyssinus (32%) and Tyrophagus putrescentiae (5.3%). There were significant differences among climatic regions. The coastal sector had greater mite abundance, being D. pteronyssinus more frequent and abundant than D. farinae. In inland areas D. farinae was the predominant mite species. Allergen levels correlated with the concentration of Dermatophagoides, with higher levels detected in coastal regions. Average annual temperature was the main outdoor factor that correlated with higher mite concentrations. Indoor main predictor of higher levels of mites was the presence of obvious signs of humidity in the home. CONCLUSION: This study demonstrates the existence of a mite fauna dominated by D. pteronyssinus and D. farinae with a strong influence of climatic factors and residential characteristics.

The 8-year follow-up of the PIAMA intervention study assessing the effect of mite-impermeable mattress covers.

BACKGROUND: Exposure to high levels of house dust mite (HDM) allergens is associated with the development of allergic sensitization to HDM, a risk factor for the development of asthma, rhinitis, and allergic dermatitis. We studied the effect of an early intervention with mite-impermeable mattress covers on HDM allergen levels and the development of asthma and mite allergy throughout the first 8 years of life. METHODS: High-risk children (allergic mother) were prenatally recruited and randomly allocated to two groups receiving mite allergen-impermeable (n = 416) and placebo mattress covers (n = 394) or no intervention (n = 472). Asthma and allergies were assessed yearly by questionnaire. Specific immunoglobulin E and bronchial hyper-responsiveness were measured at the age of 8 years. Mattress dust samples collected at different time points were analyzed for HDM allergens. RESULTS: At the age of 8 years, levels of HDM allergen Der f1 but not Der p1 were lower in the active than the placebo mattress cover group. In repeated measures analyses, we found a temporary decreased risk of asthma symptoms at the age of 2 years in the intervention group compared to the placebo group and a temporary association between higher HDM allergen exposure at the age of 3 months and more asthma symptoms. CONCLUSION: Early intervention with mite-impermeable mattress covers is successful in reducing exposure to Der f1; it only temporarily reduces the risk of asthma symptoms and does not reduce the risk of hay fever, eczema, and allergic sensitization.

Does bedding affect the airway and allergy?

Various cross-sectional and longitudinal studies have suggested that synthetic bedding is associated with asthma, allergic rhinitis and eczema while feather bedding seems to be protective. Synthetic bedding items have higher house dust mite allergen levels than feather bedding items. This is possibly the mechanism involved although fungal and bacterial proinflammatory compounds and volatile organic compounds may play a role. In this review we present and discuss the epidemiological evidence and suggest possible mechanisms. Primary intervention studies are required to show whether feather bedding is protective for the development of childhood asthma and allergic diseases while secondary intervention studies are required to potentially reduce symptoms and medication use in subjects with established disease.

Bedbug infestation and its control practices in Gbajimba: a rural settlement in Benue state, Nigeria.

BACKGROUND & OBJECTIVES: The common bedbug Cimex lectularius Linnaeus 1758 (Hemiptera: Cimicidae) is a globally re-emerging pest of serious public health concern. We investigated bedbug infestation in randomly selected apartments in Gbajimba community in Guma Local Government area in Benue state, Nigeria. METHODS: Beddings and furniture (bed frames, pillows, mattresses, cushion chairs, mats, mosquito nets and bamboo beds) were thoroughly inspected for bedbug infestation using the hand-picking technique. Data were analysed using chi- square analysis for differences in the infestation levels in harbourages and sampling locations. RESULTS: Only 16% of the apartments investigated showed no evidence of bedbug infestation as egg cases and faecal marks were sighted in 62.2% of apartments surveyed. The highest infestation rate was observed in Angwan Jukun area and infestation here was higher compared to other study locations within the town though the difference was not statistically significant (x2 = 7.92, df = 6, p >0.05). Bamboo beds harboured the highest number of bedbugs collected, accounting for 35.8%, while other harbourages like iron bed frames and sleeping mats had 23 and 22.7% infestation rates respectively. The infestation rates in these household items were significantly higher than other items inspected (x2 = 11.8, df = 4, p > 0.05). INTERPRETATION & CONCLUSION: This study demonstrates the urgent need for identification of evidences of infestation and bedbug management involving community participation in inspection, detection and education, including physical removal and exclusion as well as pesticide application.