A survey of patients with bed bugs in the emergency department

A metatranscriptomic evaluation of viruses in field-collected bed bugs

Cimex lectularius, known as the common bed bug, is a widespread hematophagous human ectoparasite and urban pest that is not known to be a vector of any human infectious disease agents. However, few studies in the era of molecular biology have profiled the microorganisms harbored by field populations of bed bugs. The objective of this study was to examine the viruses present in a large sampling of common bed bugs and related bat bugs (Cimex pipistrelle). RNA sequencing was undertaken on an international sampling of > 500 field-collected bugs, and multiple workflows were used to assemble contigs and query these against reference nucleotide databases to identify viral genomes. Shuangao bed bug virus 2, an uncharacterized rhabdovirus previously discovered in Cimex hemipterus from China, was found in several bed bug pools from the USA and Europe, as well as in C. pipistrelle, suggesting that this virus is common among bed bug populations. In addition, Shuangao bed bug virus 1 was detected in a bed bug pool from China, and sequences matching Enterobacteria phage P7 were found in all bed bug pools, indicating the ubiquitous presence of phage-derived elements in the genome of the bed bug or its enterobacterial symbiont. However, viral diversity was low in bed bugs in our study, as no other viral genomes were detected with significant coverage. These results provide evidence against frequent virus infection in bed bugs. Nonetheless, our investigation had several important limitations, and additional studies should be conducted to better understand the prevalence and composition of viruses in bed bugs. Most notably, our study largely focused on insects from urban areas in industrialized nations, thus likely missing infrequent virus infections and those that could occur in rural or tropical environments or developing nations.

Perspective on Biology and Management of Bed Bugs: Introduction

Bed bugs are an important group of medical and urban insect pests. They are obligate blood-feeders. Their bites may cause skin irritation and allergic reactions and, under some circumstances, may lead to mental and other health issues. Despite numerous discoveries on the biology of these obnoxious pests and progress in control strategies over the last two decades, bed bugs continue to preferentially plague those from low socioeconomic communities because the poor generally could not afford effective control options. As a result, such infestations in poorer communities serve as a reservoir for wider society. This Special Collection of the Perspective on Biology and Management of Bed Bugs presents nine original research papers on bed bug detection, insecticide performance and resistance, nonchemical treatment, fungal biopesticides, and pest management procurement and contracts. We hope that these investigative findings will spur research on safer, more affordable, and effective control options in the future.

Analysis of Patients With Bed Bugs in the Emergency Department

The objective was to evaluate the clinical characteristics, triage information, diagnostic evaluation, and disposition for emergency department patients with and without bed bug infestation. A retrospective case-control study of patients with and without bed bugs was performed from February 1, 2011, through February 1, 2017. Cases (n = 332) and controls (n = 4,952) were matched by age, sex, and emergency department location. Patient characteristics and clinical information were compared between groups. On univariable and multivariable analysis, patients with bed bugs had higher heart rate, lower systolic blood pressure, higher pain scores, and more frequent tobacco use in the past year. They were also more likely to screen positive in triage for an unsafe home; require an abuse consultation; be diagnosed in the emergency department or inpatient setting with malnutrition, marasmus, and/or cachexia; have more emergency department and hospital visits; and have longer hospital encounter lengths of stay (all p ≤ 0.02). On univariable analysis, patients with bed bugs were also more likely than uninfested controls to be single, be Black, come to the emergency department from home, arrive to the emergency department by ambulance, and not be discharged back to their homes from the hospital.

Respiratory diseases in patients with bed bugs

INTRODUCTION

Some arthropods such as cockroaches can exacerbate asthma, but it is unknown is this is true of bed bugs.

OBJECTIVES

The objective of this work is to determine if bronchospastic diseases like asthma and chronic obstructive pulmonary disease (COPD) would be higher for ED patients who have bed bug infestation compared with patients who do not have bed bug infestation.

METHODS

A case-control study was performed with 332 adult emergency department (ED) patients with bed bug infestation and 4952 without infestation. Univariable and multivariable regression analysis was performed.

RESULTS AND CONCLUSION

Patients with bed bug infestation were not more likely to have a past history of or an ED diagnosis of asthma or chronic obstructive pulmonary disease (COPD). However, bed bug infested patients were significantly more likely to undergo chest radiography, be admitted to the hospital, and receive albuterol in the ED (P < 0.05). Infested patients receiving albuterol in the ED were more likely to be admitted to the hospital compared with uninfested patients receiving albuterol (P < 0.001). Patients with an ED or inpatient diagnosis of asthma or COPD and bed bugs (compared with those without bed bugs) had significantly more ED visits during the study (P < 0.03). Bed bug infestations may be associated with respiratory pathology, which requires further investigation.

Association between bed bugs and allergic reactions

AIMS

To evaluate whether bed bugs are associated with allergic reactions in patients seen in the emergency department (ED).

METHODS AND RESULTS

This retrospective study included data from 9 EDs in Ohio between February 2011 and February 2017. The study comprised 332 patients with bed bug infestation matched 1:15 with 4952 control patients without bed bugs on the basis of age, sex and the presenting ED. Compared with uninfested patients, patients infested with bed bugs were more likely to have an ED or inpatient diagnosis of pruritus, hives or urticaria (odds ratio [OR], 9.12 [95% CI, 3.41-24.42]) and to be treated in the ED with an antihistamine (OR, 3.20 [95% CI, 1.87-5.50]) or albuterol (OR, 1.59 [95% CI, 1.07-2.36]) (P ≤ .02 for all). There were no significant differences in the rates of anaphylaxis and angioedema diagnosed in patients with and without bed bugs, which occurred in <1% in both groups.

CONCLUSION

Bed bug-infested patients are more likely to be diagnosed and treated for itchy cutaneous rashes, but are not clearly associated with more severe allergic reactions.

Bed bugs are associated with anemia

INTRODUCTION

Bed bugs are hematophagous insects that can be problematic in some urban emergency departments. The objective was to determine if red blood cell (RBC) and coagulation indices of bed bug-infested emergency department (ED) patients differed from those of noninfested control patients.

METHODS

A chart review from a single health system was performed for ED patients between February 1, 2011, and February 1, 2017. Bed bug-infested patients were matched to noninfested control patients on the basis of age, sex, and the presenting ED. Variables were analyzed with the t-test and Pearson χ² test and were modeled with multivariable logistic regression.

RESULTS

The study had 332 bed bug-infested patients and 4952 controls. Infested patients had lower hemoglobin (11.7 g/dL vs 12.8 g/dL), hematocrit (35.0% vs 37.9%), RBC counts (4.1 × 10⁹/L vs 4.4 × 10⁹/L), mean corpuscular volume (86.0 vs 87.5 fL/cell), and mean corpuscular hemoglobin concentrations (33.2 vs 33.7 g/dL) and higher RBC distribution width-coefficient of variation (RDW-CV) (15.2% vs 14.2%) than noninfested patients (all P ≤ .003). Infested patients were more likely to be anemic (59.5% vs 36.9%) and to have severe anemia (4.4% vs 0.7%) (P < .001 for both). Blood transfusions were more common in those with bed bugs (5.1%) than those without bed bugs (2.3%) (P < .001).

CONCLUSION

Bed bug infestated patients in the ED are associated with anemia.

Knowledge, Experience, and Concerns Regarding Bed Bugs Among Emergency Medical Service Providers

Introduction

Bed bugs are commonly encountered by emergency medical service (EMS) providers. The objective of this study was to determine the frequency with which EMS providers encountered bed bugs, assess their knowledge about bed bugs, and analyze the actions they take after finding bed bugs.

Methods

We anonymously surveyed 407 EMS providers from 180 EMS agencies in northeast Ohio between September 1, 2018, through March 31, 2019.

Results

Among the providers surveyed, 21% (n = 84) of the EMS providers reported seeing bed bugs at least monthly, and 6% (n = 24) reported seeing bed bugs at least weekly. Being younger, male, and working in an urban environment (vs. rural) were associated with EMS providers reporting more frequent bed bug encounters (p: ≤.05). The mean level of concern for encountering bed bugs among EMS providers was 3.54 (SD: 1.15; scale: 1 = no concern, 5 = very concerned). Among the EMS providers who reported seeing bed bugs at least monthly, 30% took the affected EMS stretcher out of service when they encounter a bed bug, 43% took the EMS rig out of service, 83% cleaned the EMS stretcher with a disinfectant, and 88% notified the ED that their patient has bed bugs. EMS providers scored poorly (mean: 69% correct responses) in a seven-question assessment of basic bed bug biology and public health.

Conclusion

Based on our findings, we concluded that EMS knowledge and behavior related to bed bugs are suboptimal.

A Preliminary Report Showing Spinosad and Fluralaner Are Able to Incapacitate Cimex lectularius L., the Common Bed Bug

Cimex lectularius L., the common bed bug, is a hematophagous human ectoparasite. The veterinary drugs, spinosad and fluralaner, were studied for their ability to incapacitate C. lectularius when administered in a blood meal using an artificial feeding system under laboratory conditions. Tested drug doses were based on the reported peak blood levels in animals given the drugs. Spinosad at doses 1,000 ng/mL or higher resulted in 75% or greater bed bug incapacitation (defined as death or immobility). Fluralaner at doses 500 ng/mL or higher had 100% bed bug incapacitation. Both drugs were significantly more effective than controls at these doses (P < 0.001).

The Benefit of a Single Oral Dose of Ivermectin in Humans: The Adverse Effects on Cimex lectularius L. Populations and Fecundity

Objective

To measure the population size and fecundity of the common bed bug Cimex lectularius L. (C. lectularius) after feeding it with the blood obtained from human subjects who have consumed a single dose of ivermectin.

Methods 

Serial blood samples were obtained from two human subjects at hour 0 (control) and 4-96 hours after they received a single 0.2 mg/kg dose of ivermectin. The blood samples were then fed to 2,273 bed bugs. Bed bug incapacitation rates, fecundity, and population sizes were recorded over a 54-day period. Whole blood ivermectin levels were measured in the human subjects and the insects.

Results 

The fold change in the size of the control group population over the course of the experiment was found to be 2.16. This was significantly greater (p: <.001) than for all the post-ivermectin feeding groups (range: -11.04-1.43). Two weeks after the experiment, the number of eggs laid per live adult female bed bug per day was 10.74 for controls, which was significantly different (p: <0.001) compared to all the post-ivermectin feeding groups (range: 0-4.28).

Conclusions 

There were significant reductions in C. lectularius population size and fecundity in insects that fed on blood obtained from human study subjects up to 96 hours after they have consumed a single oral dose of ivermectin.

Cimicosis in Persons Previously Fed Upon by Bed Bugs

Introduction

Bed bug infestations have risen dramatically in many industrialized nations in recent decades. Most people fed upon by bed bugs will develop a pruritic rash although the frequency with which this occurs is not definitively known and may depend on host factors including the duration of the infestation.

Methods

Surveys were completed from 706 emergency department (ED) patients in Cleveland, OH about their current and past exposure with bed bugs. Subjects were asked about any post-bed bug feeding rashes that developed.

Results

There were 24% (169/698) of subjects reporting either a current or past home bed bug infestation, with 37% (253/698) reporting they had previously been fed upon by a bed bug. Of those reporting a previous bed bug feeding, 68% (172/253) reported a pruritic post-bed bug feeding rash and 24% (57/237) reported developing a blister. Overall, 5% (37/705) of ED patients reported currently having a rash, but only 2% (14/698) of ED patients reported currently have bed bugs at home and of those, only 14% (2/14) said they currently had a rash.

Conclusion

While 68% of ED patients reported a pruritic post-bed bug feeding pruritic rash, almost a third of persons did not report developing the rash. Post-bed bug feeding blister reactions are less common. Asking ED patients about a rash had a low sensitivity of 14% (2-43%) and a specificity 95% (93-96%) to identify persons reporting home bed bugs.

A Case Study of Cimex lectularius L. (Hemiptera: Cimicidae) Infestations in an Office Environment

Most field studies on Cimex lectularius are conducted in residential or hospitality industrial settings. Cimex lectularius infestations in office settings are reported, but are rarely studied. An office environment (~875 m2) consisting of 105 cubicles or pod-seating areas with persistent C. lectularius sightings over a 2-yr period was evaluated for 90 d through intensive trapping to determine C. lectularius distribution and to eliminate the infestation. The study area was partially occupied during the study period. Two treatments of amorphous silica dust (112.5 g dust in total) were applied 29 and 57 d after the first day of monitoring. A total of 32 C. lectularius were captured by interceptors over a period of 55 d. Dry ice traps captured eight additional C. lectularius. Visual inspections identified one chair with live C. lectularius and eggs. The infestation was eliminated on 69 d after initial installation of interceptors. Spatial analysis using Ripley's K and L functions showed a high level of aggregation up to a 15 meter scale. Dispersal of C. lectularius in office settings was limited. Intensive trapping plus limited insecticide dust treatments effectively detected and eliminated C. lectularius.

Characteristics of Bed Bug Infested Patients in the Emergency Department

Cimex lectularius L., the common bed bug, is a hematophagous human ectoparasite that has undergone a global resurgence in the past two decades. We surveyed 706 active emergency department (ED) patients about their experiences with bed bugs. We found that 2% of ED patients reported having a current bed bug infestation, significantly more than the historical number of ED patients upon which we find bed bug; 37% of ED patients report previously having been fed on by a bed bug; 15% currently know someone with an active infestation; and 59% know someone that has had an infestation within ≤ 5 years. Only 18% of bed bug infested patients reported their infestation to emergency medicine providers and only 21% were put in isolation precautions. We found that 25% of patients with bed bugs worried about receiving worse healthcare because of their infestation. Persons with bed bugs were more likely compared to those without bed bugs to be older (52 vs. 41 years) and arrive by ambulance (57% vs. 14%) (p < 0.05), but not reporting insomnia (50% vs. 49%) (p = 1.0). Bed bug infested patients can be common in the ED. Most bed bug infested patients are older, arrive to the ED by ambulance, do not report their infestation to healthcare providers, and are not adequately placed into isolation precautions, potentially putting other patients and providers at risk for acquiring the infestation.