Plasma Levels of Secreted Cytokines in Virologically Controlled HIV-Infected Aging Adult Individuals on Long-Term Antiretroviral Therapy.

HIV-infected (HIV+) aging adult individuals who have achieved undetectable viral load and improved CD4 T cell counts due to long-term antiretroviral therapy (ART) may continue to experience inflammation and immunosenescence. Therefore, we evaluated the plasma levels of proinflammatory and anti-inflammatory cytokines in 173 HIV+ aging adult individuals with age ranging from 22 to 81 years on long-term ART with viral load mostly <20 HIV RNA copies/mL and compared with 92 HIV-uninfected (HIV- or healthy controls) aging individuals. We found that the median levels of TNF-α, IFN-γ, IL-1ß, IL-6, and IL-10 were higher (p < 0.001 to <0.0001) and IL-17 trended lower in HIV+ individuals than healthy controls. Increasing CD4 T cell counts in the HIV+ cohort did not significantly change the circulating cytokine levels, although levels of IL-1ß increased. However, IL-17 levels significantly decreased with increasing CD4 counts in the healthy controls and yet unchanged in the HIV+ cohort. Of note, the levels of circulating IL-17 were significantly reduced comparatively in the healthy controls where the CD4 count was below 500, yet once above 500 the levels of CD4, IL-17 levels were comparable with the HIV+ cohort. With increasing CD8 T cell counts, the levels of these cytokines were not significantly altered, although levels of TNF-α, IFN-γ, and IL-6 declined, whereas IL-1ß and IL-17 were slightly elevated. Furthermore, increasing age of the HIV+ cohort did not significantly impact the cytokine levels although a slight increase in TNF-α, IL-6, IL-10, and IL-17 was observed. Similarly, these cytokines were not significantly modulated with increasing levels of undetectable viral loads, whereas some of the HIV+ individuals had higher levels of TNF-α, IFN-γ, and IL-1ß. In summary, our findings show that HIV+ aging adult individuals with undetectable viral load and restored CD4 T cell counts due to long-term ART still produce higher levels of both proinflammatory and anti-inflammatory cytokines compared with healthy controls, suggesting some level of inflammation.

Evaluation of Real-World Vancomycin Dosing and Attainment of Therapeutic Drug Monitoring Targets.

In 2020, the Infectious Diseases Society of America (IDSA) recommended a change in vancomycin therapeutic drug monitoring from trough-based to AUC/MIC-based to optimize vancomycin's efficacy and reduce nephrotoxicity. Many hospitals have not implemented this change due to barriers such as the cost of AUC/MIC software and lack of provider familiarity. The purpose of this study was to determine the rate of AUC/MIC ratio target attainment using current trough-based vancomycin dosing practices at a city hospital. The rates of acute kidney injury (AKI) were also evaluated. Vancomycin orders were reviewed retrospectively to determine the expected AUC/MIC ratios using first-order pharmacokinetic equations over a 7-month period. Orders were excluded if they were written for a one-time dose, for individuals less than 18 years of age, or for those on hemodialysis. A total of 305 vancomycin orders were included in this review. Overall, 27.9% (85/305) of vancomycin orders attained the AUC/MIC ratio target of 400-600 mg·h/L as recommended by the guidelines. Nearly 35% (106/305) achieved AUC/MIC ratios below 400 mg·h/L and 37.4% (114/305) achieved AUC/MIC ratios above 600 mg·h/L. Orders for obese patients were significantly more likely to have below the target AUC/MIC ratios (68% vs. 23.9%, X2 48.48, p < 0.00001) and non-obese patients were significantly more likely to have above the target AUC/MIC ratios (45.7% vs. 12%, X2 27.36, p < 0.00001). The overall rate of acute kidney injury observed was 2.6%. Most vancomycin orders did not attain therapeutic drug monitoring targets, reflecting the ongoing clinical challenge of optimizing vancomycin doses and implementing new guideline recommendations.

Antimicrobial Stewardship Practices in a Subset of Community Pharmacies across the United States.

BACKGROUND: Antimicrobial stewardship in the community is essential as most antibiotic prescribing occurs in the outpatient setting. Pharmacists are recognized as co-leaders for implementing efforts to improve antimicrobial use. OBJECTIVES: the purpose of this study is to evaluate current antimicrobial stewardship practices in community pharmacies across the United States and identify perceptions and challenges faced by community pharmacists. METHODS: a survey based on the Center of Disease Control and Prevention (CDC) Core Elements of Outpatient Antibiotic Stewardship was created and distributed. RESULTS: Sixty-one community pharmacists participated in the survey. The majority of pharmacists practiced in chain pharmacies. Based on the responses, a minority of pharmacies met the requirements of the CDC core elements: commitment (27.9%), action (24.6%), tracking and reporting (14.8%), and education and expertise (23% for providing pharmacist resources and 9.8% for providing patient resources). Regarding perception, 67.9% felt antimicrobial stewardship is important in the community and would participate in antimicrobial stewardship activities if the opportunity was provided (88.5%). Challenges faced by community pharmacists include the lack of time, staff, training, and technology support; pushback from prescribers and patients; and the lack of leadership, financial incentives, funding, and legal requirements. CONCLUSIONS: many challenges exist in community pharmacies inhibiting the full potential of pharmacists in implementing antimicrobial stewardship.

Initial Use of 100% but Not 60% or 30% Oxygen Achieved a Target Heart Rate of 100 bpm and Preductal Saturations of 80% Faster in a Bradycardic Preterm Model.

Background: Currently, 21−30% supplemental oxygen is recommended during resuscitation of preterm neonates. Recent studies have shown that 58% of infants < 32 week gestation age are born with a heart rate (HR) < 100 bpm. Prolonged bradycardia with the inability to achieve a preductal saturation (SpO2) of 80% by 5 min is associated with mortality and morbidity in preterm infants. The optimal oxygen concentration that enables the achievement of a HR ≥ 100 bpm and SpO2 of ≥80% by 5 min in preterm lambs is not known. Methods: Preterm ovine model (125−127 d, gestation equivalent to human neonates < 28 weeks) was instrumented, and asphyxia was induced by umbilical cord occlusion until bradycardia. Ventilation was initiated with 30% (OX30), 60% (OX60), and 100% (OX100) for the first 2 min and titrated proportionately to the difference from the recommended preductal SpO2. Our primary outcome was the incidence of the composite of HR ≥ 100 bpm and SpO2 ≥ 80%, by 5 min. Secondary outcomes were to evaluate the time taken to achieve the primary outcome, gas exchange, pulmonary/systemic hemodynamics, and the oxidative injury. Results: Eighteen lambs (OX30-6, OX60-5. OX100-7) had an average HR < 91 bpm with a pH of <6.92 before resuscitation. Sixty seven percent achieved the primary outcome in OX100, 40% in OX60, and none in OX30. The time taken to achieve the primary outcome was significantly shorter with OX100 (6 ± 2 min) than with OX30 (10 ± 3 min) (* p = 0.04). The preductal SpO2 was highest with OX100, while the peak pulmonary blood flow was lowest with OX30, with no difference in O2 delivery to the brain or oxidative injury by 10 min. Conclusions: The use of 30%, 60%, and 100% supplemental O2 in a bradycardic preterm ovine model did not demonstrate a significant difference in the composite primary outcome. The current recommendation to use 30% oxygen did not achieve a preductal SpO2 of 80% by 5 min in any preterm lambs. Clinical studies to optimize supplemental O2 in depressed preterm neonates not requiring chest compressions are warranted.

Blocking Serum Amyloid-P Component from Binding to Macrophages and Augmenting Fungal Functional Amyloid Increases Macrophage Phagocytosis of Candida albicans.

Candida-macrophage interactions are important immune defense responses associated with disseminated and deep-seated candidiasis in humans. Cells of Candida spp. express functional amyloids on their surfaces during the pathogenesis of disseminated candidiasis. These amyloids become decorated with serum amyloid P-component (SAP) that binds to Candida cells and macrophages and downregulates the cellular and cytokine response to the fungi. In this report, further characterization of the interactions of SAP and fungal functional amyloid are demonstrated. Blocking the binding of SAP to macrophage FcγR1 receptors increases phagocytosis of yeast cells; seeding a pro-amyloid-forming peptide on the yeast cell surface also increases phagocytosis of yeasts by macrophages; and, lastly, miridesap, a small palindromic molecule, prevents binding of SAP to yeasts and removes SAP that is bound to C. albicans thus, potentially increasing phagocytosis of yeasts by macrophages. Some, or all, of these interventions may be useful in boosting the host immune response to disseminated candidiasis.

Phenotypic frailty in people living with HIV is not correlated with age or immunosenescence.

BACKGROUND: It has been hypothesized that HIV-1 infection prematurely "ages" individuals phenotypically and immunologically. We measured phenotypic frailty and immune "aging" markers on T-cells of people living with HIV on long term, suppressive anti-retroviral therapy (ART) to determine if there is an association between frailty and immunosenescence. METHODS: Thirty-seven (37) community-dwelling people living with HIV were measured for frailty using a sensor-based frailty meter that quantifies weakness, slowness, rigidity, and exhaustion. An immunological profile of the patients' CD4+ and CD8+ T-cell expression of cell surface proteins and cytokines was performed (n = 20). RESULTS: Phenotypic frailty prevalence was 19% (7/37) and correlated weakly with the number of past medical events accrued by the patient (r = 0.34, p = .04). There was no correlation of frailty with age, sex, prior AIDS diagnosis or HIV-1 viral load, or IFN-γ expression by CD4+ or CD8+ T-cells. There were more immune competent (CD28+ CD57-) cells than exhausted/senescent (CD28- CD57+) T cells. CONCLUSION: Frailty in people living with HIV on long term, suppressive ART did not correlate with aging or T cell markers of exhaustion or immunosenescence.

Placental transfusion during neonatal resuscitation in an asphyxiated preterm model.

BACKGROUND: Neonatal Resuscitation Program does not recommend placental transfusion in depressed preterm neonates. METHODS: Our objectives were to study the effect of delayed cord clamping (DCC) with ventilation for 5 min (DCCV, n-5), umbilical cord milking (UCM) without ventilation (n-6), UCM with ventilation (UCMV, n-6), early cord clamping followed by ventilation (ECCV, n-6) on red cell volume (RCV), and hemodynamic changes in asphyxiated preterm lambs. Twenty-three preterm lambs at 127-128 days gestation were randomized to DCCV, UCM, UCMV, and ECCV. We defined asphyxia as heart rate <100/min. RESULTS: The UCMV had the highest neonatal RCV as a percentage of fetoplacental volume compared to the other groups (UCMV 85.5 ± 10%, UCM 72 ± 10%, ECCV 65 ± 14%, DCCV 61 ± 10%, p < 0.01). The DCCV led to better ventilation (66 ± 1 mmHg) and higher pulmonary blood flow (75 ± 24 ml/kg/min). The carotid flow was significantly higher in UCM without ventilation. The fluctuations in carotid flow with milking were 25 ± 6% higher from baseline during UCM, compared to 6 ± 3% in UCMV (p < 0.01). CONCLUSIONS: Cord milking with ventilation led to higher RCV than other interventions. Ventilation during cord milking reduced fluctuation in carotid flow compared to UCM alone. DCCV led to better ventilation and pulmonary blood flow but did not increase RCV. IMPACT: The best practice of placental transfusion in a depressed preterm neonate remains unknown. Ventilation with an intact cord improves gas exchange and hemodynamics in an asphyxiated preterm model. Cord milking without ventilation led to lower red cell volume but higher carotid blood flow fluctuations compared to milking with ventilation. Our data can be translated to bedside and could impact preterm resuscitation.

Assessment of the Implementation of AUC Dosing and Monitoring Practices With Vancomycin at Hospitals Across the United States.

INTRODUCTION: The latest vancomycin therapeutic drug monitoring guidelines for serious MRSA infections have made a pivotal change in dosing, switching from targeting trough levels to AUC dosing. Because of these new recommendations, antimicrobial stewardship programs across the country are tasked with implementing AUC based dosing. OBJECTIVES: To assess plans for institutional adoption of vancomycin AUC dosing programs and perceptions of currently used programs in hospitals across the US. METHODS: An electronic survey was distributed to members of the American College of Clinical Pharmacy IDprn Listserv and American Society of Health-System Pharmacists between May and June 2020 to assess current institutional vancomycin dosing. Institutional program use and multiple software user parameters were analyzed using descriptive statistics. RESULTS: Two hundred two pharmacists responded to the survey with the majority practicing in institutions with 251-500 beds. Most respondents have yet to implement AUC dosing (142/202, 70.3%) with many of them planning to do so in the next year (81/142, 57.0%). Of those that already implemented AUC dosing programs, purchased Bayesian software (23/60, 38.3%) and homemade software (21/60, 35.0%) were the 2 methods most frequently utilized. Purchased Bayesian software users were more likely to recommend their software to other institutions and ranked user friendliness higher compared to non-purchased software. CONCLUSION: Most respondents have not made the switch to vancomycin AUC dosing, but there is a growing interest with many institutions looking to adopt a program within the next year.

A Peer Educational Tool to Promote Antimicrobial Stewardship on a University Campus.

Antibiotic resistance is a major public health threat. Patient education on the appropriate use of antibiotics is a key component in combating antimicrobial resistance. The purpose of this study was to analyze the utility of an origami fortune teller as a novel peer educational tool in promoting antimicrobial stewardship on a university campus. An origami fortune teller, with various case scenarios to demonstrate key antibiotic principles, was developed and used by peer educators to educate students attending a university wellness fair. The case studies included: antibiotic indications; differentiation between viral vs. bacterial infection; proper use of antibiotics; non-pharmacologic measures to combat infection; and antibiotic resistance. Students were asked to take an assessment pre and post working with the tool. One hundred and forty-three students received education using the novel tool. A significant improvement in the assessment score was observed after education was completed using the novel tool (69.5 vs. 96.6 p ≤ 0.05).

A Population-Based Study of COVID-19 Infection Among Childhood Cancer Survivors.

Childhood cancer survivors are known to be at risk of chronic co-morbidities, although their risk of COVID-19 infection remains uncertain. Understanding the risk of COVID-19 in this population is necessary to counsel survivors and inform potential mitigation strategies. The objective of this study was to determine whether the rates of COVID-19 infection differed between childhood cancer survivors and the general population. Administrative health care data from a population-based registry of children and adolescents diagnosed with cancer in Ontario, Canada, were linked with a universal health insurance registry and a repository of laboratory data. Rates of COVID-19 testing, test positivity and infection between March 1, 2020 and March 31, 2021 among childhood cancer survivors (n = 10 242) were compared to matched controls from the general population (n = 49 068). Compared to the general population, childhood cancer survivors were more likely to have COVID-19 testing (35.9% [95% CI, 34.5-37.4%] vs. 32.0% [95% CI, 31.4-32.6%]), but had a lower likelihood of positive COVID-19 result among those tested (4.3% [95% CI, 3.6-4.9%] vs. 5.5% [95% CI, 5.1-5.8%]) and a similar rate of infection among all subjects at risk (1.5% [95% CI, 1.3-1.8%] vs. 1.7% [95% CI, 1.6-1.9%]). These findings can inform counseling of survivors and clinician recommendations for this population.

Resuscitation with an Intact Cord Enhances Pulmonary Vasodilation and Ventilation with Reduction in Systemic Oxygen Exposure and Oxygen Load in an Asphyxiated Preterm Ovine Model.

(1) Background: Optimal initial oxygen (O2) concentration in preterm neonates is controversial. Our objectives were to compare the effect of delayed cord clamping with ventilation (DCCV) to early cord clamping followed by ventilation (ECCV) on O2 exposure, gas exchange, and hemodynamics in an asphyxiated preterm ovine model. (2) Methods: Asphyxiated preterm lambs (127-128 d) with heart rate <90 bpm were randomly assigned to DCCV or ECCV. In DCCV, positive pressure ventilation (PPV) was initiated with 30-60% O2 and titrated based on preductal saturations (SpO2) with an intact cord for 5 min, followed by clamping. In ECCV, the cord was clamped, and PPV was initiated. (3) Results: Fifteen asphyxiated preterm lambs were randomized to DCCV (N = 7) or ECCV (N = 8). The inspired O2 (40 ± 20% vs. 60 ± 20%, p < 0.05) and oxygen load (520 (IQR 414-530) vs. 775 (IQR 623-868), p-0.03) in the DCCV group were significantly lower than ECCV. Arterial oxygenation and carbon dioxide (PaCO2) levels were significantly lower and peak pulmonary blood flow was higher with DCCV. (4) Conclusion: In asphyxiated preterm lambs, resuscitation with an intact cord decreased O2 exposure load improved ventilation with an increase in peak pulmonary blood flow in the first 5 min.

Use of a Structured Method of Antimicrobial Stewardship at a City Hospital by Pharmacy Students.

The objective of this study was to determine the utility of a structured method of antimicrobial stewardship by Advanced Pharmacy Practice Experience students and assess student perceptions of the tool. Pharmacy students on rotation were trained to utilize a structured team antibiotic review form (TARF) as a tool to participate in antimicrobial stewardship. Students completed anonymous evaluations regarding their confidence in performing stewardship after completing their rotation, and preceptors quantified total student interventions. Data analysis was conducted using descriptive statistics. The Fisher's Exact Test was used to compare students' confidence before and after using TARFs. Twenty-six students participated in antimicrobial stewardship using TARFs, resulting in 889 interventions. Nearly 96% of students reported that TARFs helped them evaluate patient antibiotics in a way that was easy to follow and that TARFs provided them with an organized and structured way to systematically evaluate antibiotics. All students felt that the TARFs increased their knowledge on how to evaluate antibiotics. Significantly more students were confident in participating in antimicrobial stewardship after using the TARF. TARF use allowed students to substantially contribute to stewardship, and provided them with a structured guide allowing for improved student knowledge and confidence.

A Review and Clinical Understanding of Tenofovir: Tenofovir Disoproxil Fumarate versus Tenofovir Alafenamide.

HIV is a serious chronic medical condition. Significant improvements in antiretroviral therapy have led to a transformation in its management. No curative treatment is available for HIV, and lifelong therapy is required with a combination of agents to control viral replication and prevent complications. Some of the older agents are notorious for many side effects, making patient compliance difficult, which is critical to preventing HIV resistance. Tenofovir is one of the newer, more tolerable, nucleotide reverse transcriptase inhibitors on the market; is a mainstay of many antiretroviral therapy combinations; and is now available in 2 different formulations, tenofovir disoproxil fumarate (TDF) and, the more recent, tenofovir alafenamide (TAF). These 2 formulations have very different pharmacokinetics, which seem to affect their efficacy and safety. This manuscript provides insight into the history of TDF and TAF development, their unique pharmacokinetics and pharmacology, clinically important adverse effects, monitoring, interactions, resistance, review of clinical studies, and guideline recommendations and clinical applications for tenofovir's various indications.

Kissing Bugs Harboring Trypanosoma cruzi, Frequently Bite Residents of the US Southwest But Do Not Cause Chagas Disease.

BACKGROUND: Kissing bugs are common household pests in the Desert Southwest of the United States. These hematophagous bugs enter homes and suck blood from resident humans and pets. They are vectors of Trypanosoma cruzi, an enzootic parasite in small mammals and the cause of Chagas disease in humans. Autochthonous cases of Chagas disease are rare in the United States despite the presence of the vector and parasite. Environmental and biological factors accounting for this phenomenon need studying. METHODS: Homeowners in Bisbee and Tucson, Arizona captured kissing bugs inside homes during 2017-2018. Bugs were tested for presence of T. cruzi by polymerase chain reaction. Residents bitten by kissing bugs were tested for Chagas disease by serology. We evaluated invaded homes in the 2 cities. RESULTS: Three species of kissing bugs (n = 521) were collected in or near homes. Triatoma rubida was the most common triatomine in Tucson; T. recurva in Bisbee. T. protracta was uncommon. Seventeen percent of bugs captured in Bisbee and 51.1% in Tucson harbored T. cruzi. Bite victims (n = 105) recalled more than 2200 bites. Reactions to bites were common, including 32 episodes of anaphylaxis in 11 people (10.5%). Tests for Chagas disease (n = 116) were negative. Median age of houses was 91 years in Bisbee and 7 years in Tucson. Bisbee houses had pier and beam foundations. Tucson houses were built on concrete slabs. CONCLUSIONS: Kissing bugs harboring T. cruzi readily entered new and old homes. Bites of humans caused severe, life-threatening reactions. There was no serological evidence of Chagas disease among those bitten.

Overview and Insights into Carbapenem Allergy.

Understanding antibiotic allergies and the risk of cross-sensitivity between and within antibiotic classes can have a substantial impact on patient care. The purpose of this review article is to provide insight into carbapenem allergies, describing the overall incidence, risk factors, and in-class cross-sensitivity. A PubMed search was conducted using the following search terms: carbapenem, allergy, cross-sensitivity, incidence, imipenem/cilastatin, meropenem, ertapenem, and doripenem. Article bibliographies and relevant drug monographs were also reviewed. The overall reported incidence of carbapenem allergy is 0.3%-3.7%. Risk of cross-sensitivity between penicillins and carbapenems is less than 1% in patients with a positive penicillin skin test. Data on cross-sensitivity between cephalosporins and carbapenems are limited; however, the risk appears to also be low. No clinical studies have described cross-sensitivity between the carbapenem agents thus far. The limited data available from case reports demonstrates a lack of cross-sensitivity between the individual carbapenems, suggesting that an alternative carbapenem may cautiously be used in patients with a reported carbapenem allergy.

Rapid detection of human blood in triatomines (kissing bugs) utilizing a lateral flow immunochromatographic assay - A pilot study.

OBJECTIVES: We tested a rapid and specific immunochromatographic assay (that detects human blood in forensic samples) to determine if human blood was present in triatomines and their fecal excreta. METHODS: We fed Triatoma rubida human blood (positive control) or mouse blood (negative control) and performed the assay on the abdominal contents and fecal excreta. Triatomine field specimens collected in and around human habitations and excreta were also tested. FINDINGS: The assay was positive in triatomines fed human blood (N = 5/5) and fecal excreta from bugs known to have ingested human blood (N = 5/5). Bugs feeding on mice (N = 15/15) and their fecal excreta (N = 8/8) were negative for human blood. Human blood was detected in 47% (N = 23/49) triatomines, representing six different species, collected in the field. MAIN CONCLUSIONS: The pilot study shows that this rapid and specific test may have applications in triatomine research. Further study is needed to determine the sensitivity of this assay compared to other well-established techniques, such as DNA- and proteomics-based methodologies and the assay's application in the field.

Practical Implications of New Antibiotic Agents for the Treatment of Carbapenem-Resistant Enterobacteriaceae.

OBJECTIVE: To provide insight into the practical implications of the use of ceftazidime/avibactam and meropenem/vaborbactam for the management of carbapenem-resistant Enterobacteriaceae (CRE) and to identify strategies for overcoming barriers to the use of these agents in clinical practice. DATA SOURCES: A literature search of PubMed was conducted using the following search terms: ceftazidime/avibactam, meropenem/vaborbactam, carbapenem-resistant Enterobacteriaceae, antimicrobial stewardship, and clinical laboratory standards institute. Abstracts from infectious diseases conferences, article bibliographies, and relevant drug monographs were also reviewed. STUDY SELECTION/DATA EXTRACTION: Relevant English-language studies were considered. DATA SYNTHESIS: Studies demonstrating the clinical utility of ceftazidime/avibactam and meropenem/vaborbactam over older agents for CRE were summarized. Laboratory challenges, including lack of widespread technology and delays in usable information, and formulary considerations were discussed. Insight was provided into overcoming these challenges and minimizing barriers using infectious diseases pharmacists, antimicrobial stewardship teams, and infection control teams. RELEVANCE TO PATIENT CARE AND CLINICAL PRACTICE: This review informs clinicians of the potential difficulties of the use of ceftazidime/avibactam and meropenem/vaborbactam in clinical practice and provides tools to overcome these difficulties, thus allowing clinicians to stay at the forefront of CRE treatment. CONCLUSIONS: Clinicians treating patients with CRE infections need to be aware of challenges they may face when using ceftazidime/avibactam and meropenem/vaborbactam. Infectious disease (ID) pharmacists and antimicrobial stewardship teams play an important role in minimizing barriers and ensuring appropriate use of these antibiotics.

Management of Patients with Candida auris Fungemia at Community Hospital, Brooklyn, New York, USA, 2016-20181.

Candida auris is an emerging fungus that can cause invasive infections. It is associated with high mortality rates and resistance to multiple classes of antifungal drugs and is difficult to identify with standard laboratory methods. We describe the management and outcomes of 9 patients with C. auris fungemia in Brooklyn, New York, USA.

HIV Infection-Associated Frailty: The Solution for Now Is Antiretroviral Drugs: A Perspective.

This Perspective article provides a new view of frailty as it relates to HIV-1 infection. We discuss new findings and where our research is going.

Rapid detection of human blood in triatomines (kissing bugs) utilizing a lateral flow immunochromatographic assay - A pilot study

BACKGROUND DNA- and proteomics-based techniques are currently used to identify a triatomine human blood meal. These methods are time consuming, require access to laboratories with sophisticated equipment, and trained personnel. OBJECTIVES We tested a rapid and specific immunochromatographic assay (that detects human blood in forensic samples) to determine if human blood was present in triatomines and their fecal excreta. METHODS We fed Triatoma rubida human blood (positive control) or mouse blood (negative control) and performed the assay on the abdominal contents and fecal excreta. Triatomine field specimens collected in and around human habitations and excreta were also tested. FINDINGS The assay was positive in triatomines fed human blood (N = 5/5) and fecal excreta from bugs known to have ingested human blood (N = 5/5). Bugs feeding on mice (N = 15/15) and their fecal excreta (N = 8/8) were negative for human blood. Human blood was detected in 47% (N = 23/49) triatomines, representing six different species, collected in the field. MAIN CONCLUSIONS The pilot study shows that this rapid and specific test may have applications in triatomine research. Further study is needed to determine the sensitivity of this assay compared to other well-established techniques, such as DNA- and proteomics-based methodologies and the assay's application in the field.