Who knows the bed bug? Knowledge of adult bed bug appearance increases with people's age in three counties of Great Britain

The current reemergence of bed bugs in the western world has a multitude of causes. One of them may be low early detection rate of emerging infestations because of a current poor knowledge among the population of what bed bugs look like. In a survey conducted in three counties of the United Kingdom, 10% of 358 individuals recognized the bed bug when presented with a live adult. Older people were more likely to correctly identify the bed bug. If an increasing knowledge of the bed bug appearance facilitates early detection of infestations, the hospitality and travel industry may benefit from educating their staff on the bed bug appearance.     

Bed bugs: clinical relevance and control options

Since the late 1990s, bed bugs of the species Cimex lectularius and Cimex hemipterus have undergone a worldwide resurgence. These bed bugs are blood-sucking insects that readily bite humans. Cutaneous reactions may occur and can start out as small macular lesions that can develop into distinctive wheals of around 5 cm in diameter, which are accompanied by intense itching. Occasionally, bullous eruptions may result. If bed bugs are numerous, the patient can present with widespread urticaria or eythematous rashes. Often, bites occur in lines along the limbs. Over 40 pathogens have been detected in bed bugs, but there is no definitive evidence that they transmit any disease-causing organisms to humans. Anemia may result when bed bugs are numerous, and their allergens can trigger asthmatic reactions. The misuse of chemicals and other technologies for controlling bed bugs has the potential to have a deleterious impact on human health, while the insect itself can be the cause of significant psychological trauma. The control of bed bugs is challenging and should encompass a multidisciplinary approach utilizing nonchemical means of control and the judicious use of insecticides. For accommodation providers, risk management procedures should be implemented to reduce the potential of bed bug infestations.     

Genetic analysis of bed bug populations reveals small propagule size within individual infestations but high genetic diversity across infestations from the eastern United States

Bed bugs (Cimex lectularius L.) are a resurgent pest worldwide and infestations within the United States are increasing at a rapid rate. Because of the physical and psychological discomfort inflicted by their blood feeding habits, and allergies and secondary infections associated with bites, bed bugs are recognized as a significant public health problem. Although bed bug infestations are spreading and becoming more prevalent, we have a poor understanding of their dispersal patterns and sources of infestation. To help fill this gap, we conducted a genetic study of 21 bed bug infestations from the eastern United States, nearly all of which came from single rooms within residences. We genotyped samples comprised of 8-10 individuals per infestation at nine polymorphic microsatellite loci. Despite high genetic diversity across all infestations, with 5-17 alleles per locus (mean = 10.3 alleles per locus), we found low genetic diversity (1-4 alleles per locus) within all but one of the infestations. These results suggest that nearly all the studied infestations were started by a small propagule possibly consisting of a singly mated female and/or her progeny, or a female mated with multiple males that were highly related to her. All infestations were strongly genetically differentiated from each other (mean pairwise F(ST) between populations = 0.68) and we did not find strong evidence of a geographic pattern of genetic structure, indicating infestations located in closer proximity to each other were nearly as genetically differentiated as those located hundreds of kilometers away. The high level of genetic diversity across infestations from the eastern United States together with the lack of geographically organized structure is consistent with multiple introductions into the United States from foreign sources.     

Resistance differences between chlorpyrifos and synthetic pyrethroids in Cimex lectularius population from Denmark

Bed bug, Cimex lectularius L., populations were investigated for resistance against permethrin and chlorpyrifos in a topical application bioassay, after an initial establishment of a discriminating dose with a susceptible population. For both insecticides, ca. two times the lethal dose LD₉₉ was selected: 2,560 ng of permethrin and 200 ng of chlorpyrifos per bed bug, respectively. Bed bugs were collected from infested homes in Denmark at ten locations and bred in the laboratory. The frequency of permethrin-resistant individuals was high in Danish bed bug populations as susceptible individuals were only found in three of ten populations. In contrast, the frequency of chlorpyrifos-resistant individuals was low in Danish bed bug populations, but resistant individuals were found in five of ten populations. To test the significance of the observed resistance, we performed tarsal contact test with commercially available insecticides. The test indicated that both a permethrin and a deltamethrin product had very low efficacy against the field-collected bed bug populations. Despite the reduced sensitivity to synthetic pyrethroids, all populations tested in the tarsal test on the commercial product with micro-encapsulated chlorpyrifos resulted in close to 100% mortality.     

Survival rate of bat bugs (Cimex pipistrelli, Heteroptera) under different microclimatic conditions

Survival of facultative ectoparasites, e.g. bed bugs (Cimex spp.), is more intensely affected by climatic factors, namely temperature, than that of permanent ectoparasites. The ontogenetic time of the bat bug (Cimex pipistrelli) in bat roosts is limited by different survival rates under different temperatures in particular nymphal stages. This limitation could affect bug densities and cause asynchrony between the ectoparasite and bat reproductive cycle. Therefore, bug survival under different temperatures was tested in the laboratory. Survival success was evaluated by three types of survival analyses: Kaplan–Meier estimation, the Cox proportional hazards model and Weibull parametric regression. The bugs survived for only a few hours at 45°C; however, such a high temperature was never found in natural roosts. Different survival probability among different ontogenetic stages was found at the temperatures of 5–35°C, and it was the highest in adult females and nymphs of fourth and fifth instar. Early instars first to third were found to be the most sensitive with the highest mortality of all stages studied and having their best survival at 5°C. The hazard rate ratio of Weibull regression shows the low daily failure rate of 2.23–4.34% within the span of 5–35°C. C. pipistrelli had the shorter life cycle and the better survival at higher temperature (35°C) than C. lectularius. The ability of the former to survive high temperatures could be the consequence of its long-term coexistence with bats preferring crevice-like roosts or attics which become overheated during the summer months.     

Brucella abortus RB51 Strain Sent in a Proficiency Testing Panel to Clinical and Public Health Laboratories

In early 2017, a laboratory proficiency testing panel, designed to assess laboratory competency for culture and identification of bacterial organisms, was distributed to clinical and public health microbiology laboratories. The panel included a Brucella abortus RB51 isolate. Although B. abortus RB51 is an attenuated Brucella species strain, it still poses some risk to laboratory personnel, particularly if safety precautions and personal protective equipment are not adequately deployed. The PT event highlighted the challenges that clinical and public health microbiology laboratories face when handling samples that can contain highly transmissible organisms that can lead to laboratory-acquired infections. This review describes the B. abortus RB51 PT event, its associated exposures, and subsequent medical interventions. General considerations for handling Brucella species, including RB51, in the clinical microbiology laboratory are also discussed. Finally, we describe lessons learned from this event, including improving a “culture of safety” in the clinical laboratory.     

Aerococcus urinae,Alloscardovia omnicolens, and Actinotignum schaalii: the AAA Minor League Team of Urinary Tract Infection Pathogens

In clinical microbiology laboratories, advancements in the methods used for routine organism identification have facilitated more accurate species level resolution. This, along with increasing knowledge regarding “new” pathogens, has provided new insights into biology and has revealed clinical associations not previously known. Aerococcus urinae, Alloscardovia omnicolens, and Actinotignum schaalii are Gram-positive bacteria associated with urinary tract infections but can also be members of the urinary tract microbiota. In addition, invasive infections have been reported for the three bacteria, usually with a urinary tract source. Importantly, the use of routine biochemical testing methods for identification of these bacteria can result in misidentification or the incorrect determination that they are not clinically significant. Of these bacteria, only A. urinae has antimicrobial susceptibility testing criteria and interpretative breakpoints. Microbiologists and clinicians need to be aware of these urinary tract pathogens and how to correctly identify them.     

Seasonal dynamics in the numbers of parasitic bugs (Heteroptera,Cimicidae): a possible cause of roost switching in bats (Chiroptera,Vespertilionidae)

The objective of the present paper is to extend the knowledge of roosting strategies of bats and the interaction of bats with their roost ectoparasites, the bat bugs Cimex pipistrelli. The project was focussed on the potential causality of bat movements and the variation in bug numbers. For 2 years, three model bat boxes with breeding female Pipistrellus pygmaeus were monitored inside floodplain forest. After the arrival of bats in May, adults and first instars of bugs were observed in the boxes. During the lactation period in June, when the bats did not occupy the roosts, the first instar bugs died out followed by the adults. The decrease in bug numbers began only several days after the bats had left the boxes. After a month of the bats’ absence, the abundance of adult bugs decreased by half of their number. Only the eggs survived the period when the roosts were unoccupied in summer. In mid-July, after the arrival of lactating females, an increase in the number of bugs was observed. At the beginning of August, however, no new eggs were found. Although adult C. pipistrelli are able to survive the winter period in the boxes, the bats, by shifting the roosts within the vegetation season, prevent the massive reproduction of these parasites.     

COVID-19 gone bad: A new character in the spectrum of the hyperferritinemic syndrome?

The severe form of COVID-19 share several clinical and laboratory features with four entities gathered under the term “hyperferritinemic syndromes” and including macrophage activation syndrome (MAS), adult-onset Still's disease (AOSD), catastrophic anti-phospholipid syndrome (CAPS) and septic shock. COVID-19 systemic inflammatory reaction and “hyperferritinemic syndromes” are all characterized by high serum ferritin and a life-threatening hyper-inflammation sustained by a cytokines storm which eventually leads to multi-organ failure. In this review, we analyze the possible epidemiological and molecular mechanisms responsible for hyper-inflammation in patients with severe COVID-19 and we underline the similarities between this condition and “hyperferritinemic syndromes” which would allow considering severe COVID-19 as a fifth member of this spectrum of inflammatory conditions.     

Movement of Rhodnius prolixus (Hemiptera: Reduviidae) within a simulated house environment.

We observed the movement, attraction, and resting behavior of laboratory Rhodnius prolixus St?l within a house environment, simulated by a Styrofoam box. Movement of R. prolixus into various refuge types (fiberpots or white-, cream-, or black-colored modified Gomez-Nunez boxes) at different strata was assessed. Greater numbers of fifth instars sought a refuge than third instars. Fasted nymphs sought a refuge more than fed nymphs. Our simulated house environment showed potential as a laboratory arena to observe the resting preferences, dispersal, and response of kissing bugs to potential attractants. Our data indicated that fiberpot refuges may serve as an effective and inexpensive monitoring device to detect low density kissing bug infestations.     

What is the clinical relevance of respiratory syncytial virus bronchiolitis?: findings from a multi-center, prospective study

Acute bronchiolitis (AB) is caused primarily by respiratory syncytial virus (RSV). Recent laboratory tools have implicated a variety of other pathogens; however, their clinical relevance has not been clearly defined. The purpose of this study was to determine whether the etiological agents of AB affect its course. A multicenter prospective study was performed in previously healthy children <24?months of age who presented with <4?days duration of AB. Subjects were divided into the following groups: “only RSV,” “also RSV,” “no RSV,” and “no pathogen.” The clinical severity score on admission as well as the overall severity of disease was assessed. RSV was the most common cause of AB (77.5?%). “Only RSV” or “also RSV” patients had a higher clinical score on admission compared to those with “no RSV,” p?<?0.001 and p?<?0.02, respectively. “Only RSV” and “also RSV” patients had a higher disease severity score when compared to patients with “no RSV,” 5.9?±?1.4 vs. 5.1?±?1.5, p?<?0.001, and 5.6?±?1.4 vs. 5.1?±?1.5, p?<?0.02, respectively. Disease severity did not vary as a function of transfer to the pediatric intensive care unit (PICU) or duration of supplemental oxygen, yet, “only RSV” was associated with a longer length of stay (LOS) than “no RSV,” p?<?0.02. “Only RSV”-related AB was associated with a more severe initial clinical presentation and a longer LOS. There appears to be little immediate clinical benefit to diagnosing RSV AB to the individual patient, but the application of these diagnostic methods may have significant cost-saving implications and, thus, deserves consideration by medical professionals and health policy analysts.     

How to: Diagnose inborn errors of intrinsic and innate immunity to viral,bacterial, mycobacterial,and fungal infections

BackgroundInborn errors of intrinsic and innate immunity constitute the focus of a growing research field that investigates the molecular mechanisms underlying susceptibility to infections previously not considered part of the spectrum of inborn errors of immunity. These so-called nonconventional inborn errors of immunity often occur as infections caused by a narrow spectrum of microorganisms in otherwise healthy subjects.ObjectivesThis review aimed to provide a framework for identifying and evaluating patients with viral, bacterial, mycobacterial, and fungal infection needing further assessment for inborn errors of intrinsic and innate immunity.SourcesA literature search was performed using PubMed, from inception until 1 May 2022. The search included the following keywords: “inborn errors of immunity”; “inborn errors of innate immunity”; “primary immune deficiency”; “primary immunodeficiency”; “infections”; “infectious susceptibility”; “virus”; “pyogenic bacteria”; “mycobacteria”; “fungi”. All article types were considered.ContentWe review the definition of what can be considered an inborn error of immunity and how the definition changed over the last ～25 years. We further provide criteria to rule out secondary immunodeficiencies, identify patients needing further clinical and laboratory immunological assessment, and suspect and diagnose an inborn error of intrinsic and innate immunity. These steps are proposed as part of an algorithm.ImplicationsPatients with unexplained life-threatening infections, including otherwise healthy subjects, should be systematically screened for known inborn errors of immunity. The early diagnosis can prevent recurrence of life-threatening infections in the patients and reduce the total burden of infectious diseases.     

Molecular markers reveal infestation dynamics of the bed bug (Hemiptera: Cimicidae) within apartment buildings

The bed bug, Cimex lectularius L. (Hemiptera: Cimicidae), has experienced an extraordinary global resurgence in recent years, the reasons for which remain poorly understood. Once considered a pest of lower socioeconomic classes, bed bugs are now found extensively across all residential settings, with widespread infestations established in multiapartment buildings. Within such buildings, understanding the population genetic structure and patterns of dispersal may prove critical to the development of effective control strategies. Here, we describe the development of 24 high-resolution microsatellite markers through next generation 454 pyrosequencing and their application to elucidate infestation dynamics within three multistory apartment buildings in the United States. Results reveal contrasting characteristics potentially representative of geographic or locale differences. In Raleigh, NC, an infestation within an apartment building seemed to have started from a single introduction followed by extensive spread. In Jersey City, NJ, two or more introductions followed by spread are evident in two buildings. Populations within single apartments in all buildings were characterized by high levels of relatedness and low levels of diversity, indicative of foundation from small, genetically depauperate propagules. Regardless of the number of unique introductions, genetic data indicate that spread within buildings is extensive, supporting both active and human-mediated dispersal within and between adjacent rooms or apartments spanning multiple floors.     

Discrimination of the Acinetobacter calcoaceticus–Acinetobacter baumannii complex species by Fourier transform infrared spectroscopy

The main goal of this work was to assess the ability of Fourier transform infrared spectroscopy with attenuated total reflectance (FTIR-ATR) to discriminate between the species of the Acinetobacter calcoaceticus–Acinetobacter baumannii (Acb) complex, i.e. A. baumannii, A. nosocomialis, A. pittii, A. calcoaceticus, genomic species “Between 1 and 3” and genomic species “Close to 13TU”. A total of 122 clinical isolates of the Acb complex previously identified by rpoB sequencing were studied. FTIR-ATR spectra was analysed by partial least squares discriminant analysis (PLSDA) and the model scores were presented in a dendrogram form. This spectroscopic technique proved to be effective in the discrimination of the Acb complex species, with sensitivities from 90 to 100 %. Moreover, a flowchart aiming to help with species identification was developed and tested with 100 % correct predictions for A. baumannii, A. nosocomialis and A. pittii test isolates. This rapid, low cost and environmentally friendly technique proved to be a reliable alternative for the identification of these closely related Acinetobacter species that share many clinical and epidemiological characteristics and are often difficult to distinguish. Its validation towards application on a routine basis could revolutionise high-throughput bacterial identification.     

Stercorarial shedding and transtadial transmission of hepatitis B virus by common bed bugs (Hemiptera: Cimicidae)

Transtadial persistence and stercorarial shedding of hepatitis B virus (HBV) in common bed bugs, Cimex lectularius L., was studied by using experimental infectious blood feedings, infectious intrathoracic inoculations, and virus detection by polymerase chain reaction and Southern hybridization. Results showed that HBV persisted after an infectious blood meal in bed bug bodies for up to 35 d after the infectious blood meal. It was passed transtadially through one molt regardless of instar, was shed in fecal droplets for up to 35 d after the infectious blood meal, but was not passed transovarially. In bugs inoculated intrathoracically, HBV was detected for 21 d postinoculation. Previous studies detected the hepatitis B surface antigen found on both infectious and noninfectious particles in bed bugs. In this study, the presence of nucleic acids amplified from a conserved core region of the viral genome in bodies and feces of C. lectularius suggests that the HBV virus may be mechanically transmitted in feces or when bugs are crushed, during feeding.     

Riptortus pedestris and Burkholderia symbiont: an ideal model system for insect–microbe symbiotic associations

A number of insects establish symbiotic associations with beneficial microorganisms in various manners. The bean bug Riptortus pedestris and allied stink bugs possess an environmentally acquired Burkholderia symbiont in their midgut crypts. Unlike other insect endosymbionts, the Burkholderia symbiont is easily culturable and genetically manipulatable outside the host. In conjunction with the experimental advantages of the host insect, the Riptortus–Burkholderia symbiosis is an ideal model system for elucidating the molecular bases underpinning insect-microbe symbioses, which opens a new window in the research field of insect symbiosis. This review summarizes current knowledge of this system and discusses future perspectives.     

Incorporating personalized gene sequence variants, molecular genetics knowledge, and health knowledge into an EHR prototype based on the Continuity of Care Record standard

ObjectivesThe current volume and complexity of genetic tests, and the molecular genetics knowledge and health knowledge related to interpretation of the results of those tests, are rapidly outstripping the ability of individual clinicians to recall, understand and convey to their patients information relevant to their care. The tailoring of molecular genetics knowledge and health knowledge in clinical settings is important both for the provision of personalized medicine and to reduce clinician information overload. In this paper we describe the incorporation, customization and demonstration of molecular genetic data (mainly sequence variants), molecular genetics knowledge and health knowledge into a standards-based electronic health record (EHR) prototype developed specifically for this study.MethodsWe extended the CCR (Continuity of Care Record), an existing EHR standard for representing clinical data, to include molecular genetic data. An EHR prototype was built based on the extended CCR and designed to display relevant molecular genetics knowledge and health knowledge from an existing knowledge base for cystic fibrosis (OntoKBCF). We reconstructed test records from published case reports and represented them in the CCR schema. We then used the EHR to dynamically filter molecular genetics knowledge and health knowledge from OntoKBCF using molecular genetic data and clinical data from the test cases.ResultsThe molecular genetic data were successfully incorporated in the CCR by creating a category of laboratory results called “Molecular Genetics” and specifying a particular class of test (“Gene Mutation Test”) in this category. Unlike other laboratory tests reported in the CCR, results of tests in this class required additional attributes (“Molecular Structure” and “Molecular Position”) to support interpretation by clinicians. These results, along with clinical data (age, sex, ethnicity, diagnostic procedures, and therapies) were used by the EHR to filter and present molecular genetics knowledge and health knowledge from OntoKBCF.ConclusionsThis research shows a feasible model for delivering patient sequence variants and presenting tailored molecular genetics knowledge and health knowledge via a standards-based EHR system prototype. EHR standards can be extended to include the necessary patient data (as we have demonstrated in the case of the CCR), while knowledge can be obtained from external knowledge bases that are created and maintained independently from the EHR. This approach can form the basis for a personalized medicine framework, a more comprehensive standards-based EHR system and a potential platform for advancing translational research by both disseminating results and providing opportunities for new insights into phenotype-genotype relationships.     

Natural infection of vertebrate hosts by different lineages of Buggy Creek virus (family Togaviridae, genus Alphavirus)

Buggy Creek virus (BCRV; family Togaviridae, genus Alphavirus) is an arbovirus transmitted by the ectoparasitic swallow bug (Hemiptera: Cimicidae: Oeciacus vicarius) to cliff swallows (Petrochelidon pyrrhonota) and house sparrows (Passer domesticus). BCRV occurs in two lineages (A and B) that are sympatric in bird nesting colonies in the central Great Plains, USA. Previous work on lineages isolated exclusively from swallow bugs suggested that lineage A relies on amplification by avian hosts, in contrast to lineage B, which is maintained mostly among bugs. We report the first data on the BCRV lineages isolated from vertebrate hosts under natural conditions. Lineage A was overrepresented among isolates from nestling house sparrows, relative to the proportions of the two lineages found in unfed bug vectors at the same site at the start of the summer transmission season. Haplotype diversity of each lineage was higher in bugs than in sparrows, indicating reduced genetic diversity of virus amplified in the vertebrate host. BCRV appears to have diverged into two lineages based on different modes of transmission.