Clinical evaluation of a Borrelia modified two-tiered testing (MTTT) shows increased early sensitivity for Borrelia burgdorferi but not other endemic Borrelia species in a high incidence region for Lyme disease in Wisconsin.

A modified two-tiered testing algorithm (MTTT; ZEUS Scientific) for Borrelia burgdorferi was recently FDA-cleared. We evaluated the MTTT algorithm to confirm Lyme disease and compared the findings in parallel with those obtained using standard two-tiered testing (STTT). Medical records from patients who submitted sera for laboratory confirmation of Lyme-like disease were reviewed. Three hundred twenty patient samples were run by the STTT and MTTT approaches and the results compared. Positive STTT samples were also positive by MTTT (94%). The MTTT confirmed the illness in 116 subjects (36%, P = 0.007), and 30 (26%) were negative by the STTT. Increased MTTT sensitivity was seen (P = 0.0005) during early infection. MTTT was insufficiently sensitive to identify other non-Borrelia spp. infections. Routine adoption of MTTT would improve sensitivity for early Lyme disease attributable to B. burgdorferi, but may not capture illness attributed to B. mayonii and B. miyamotoi.

Optimized infection control practices augment the robust protective effect of vaccination for ESRD patients during a hemodialysis facility SARS-CoV-2 outbreak.

BACKGROUND: While dialysis patients are at greater risk of serious SARS-CoV-2 complications, stringent infection prevention measures can help mitigate infection and transmission risks within dialysis facilities. We describe an outbreak of 14 cases diagnosed in a hospital-based outpatient ESRD facility over 13 days in the second quarter of 2021, and our coordinated use of epidemiology, viral genome sequencing, and infection control practices to quickly end the transmission cycle. METHODS: Symptomatic patients and staff members were diagnosed by RT-PCR. Facility-wide screening utilized SARS-CoV-2 antigen tests. SARS-CoV-2 genome sequences were obtained from residual diagnostic specimens. RESULTS: Of the 106 patients receiving dialysis in the facility, 10 were diagnosed with SARS-CoV-2 infection, as was 1 patient support person. Of 3 positive staff members, 2 were unvaccinated and had provided care for 6 and 4 of the affected patients, respectively. Sequencing demonstrated that all cases in the cluster shared an identical B.1.1.7./Alpha substrain. Attack rates were greatest among unvaccinated patients and staff. Vaccine effectiveness was 88% among patients. CONCLUSIONS: Prompt recognition of an infection cluster and rapid intervention efforts successfully ended the outbreak. Alongside consistent adherence to core infection prevention measures, vaccination was highly effective in reducing disease incidence and morbidity in this vulnerable population.

Emergence and onward transmission of a SARS-CoV-2 E484K variant among household contacts of a bamlanivimab-treated patient.

The implementation of monoclonal antibody therapeutics during the COVID-19 pandemic altered the selective pressures encountered by SARS-CoV-2, raising the possibility of selection for resistant variants. Within-host viral evolution was reported in treated immunocompromised individuals but whether this signifies a real risk of onward transmission is unclear. We used a regional SARS-CoV-2 sequencing program to monitor lineages with clinically relevant variants in identified patients, which facilitated analysis of parameters potentially relevant to new variant emergence. Here we describe a newly acquired spike E484K mutation detected within the B.1.311 lineage. Multiple individuals in 2 households of the same extended family were infected. The timing and patterns of spread were consistent with de novo emergence of this E484K variant in the bamlanivimab-treated index patient. Our study suggests that the selective pressures introduced by the widespread administration of these antibodies may warrant increased genomic surveillance to identify and mitigate spread of therapy-induced variants.

Outbreak or pseudo-outbreak? Integrating SARS-CoV-2 sequencing to validate infection control practices in a dialysis facility.

BACKGROUND: The COVID-19 pandemic poses a particularly high risk for End Stage Renal Disease (ESRD) patients so rapid identification of case clusters in ESRD facilities is essential. Nevertheless, with high community prevalence, a series of ESRD patients may test positive contemporaneously for reasons unrelated to their shared ESRD facility. Here we describe a series of 5 cases detected within 11 days in November 2020 in a hospital-based 32-station ESRD facility in Southwest Wisconsin, the subsequent facility-wide testing, and the use of genetic sequence analysis to evaluate links between cases. METHODS: Four patient cases and one staff case were identified in symptomatic individuals by RT-PCR. Facility-wide screening was conducted using rapid SARS-CoV-2 antigen tests. SARS-CoV-2 genome sequences were obtained from residual diagnostic specimens. RESULTS: Facility-wide screening of 47 staff and 107 patients identified no additional cases. Residual specimens from 4 of 5 cases were available for genetic sequencing. Clear genetic differences proved that these contemporaneous cases were not linked. CONCLUSIONS: With high community prevalence, epidemiological data alone is insufficient to deem a case cluster an outbreak. Cluster evaluation with genomic data, when available with a short turn-around time, can play an important role in infection prevention and control response programs.

Widespread Lichtheimia Infection in a Patient with Extensive Burns: Opportunities for Novel Antifungal Agents.

The Mucorales fungi-formerly classified as the zygomycetes-are environmentally ubiquitous fungi, but generally rare causes of clinical infections. In the immunocompromised host, however, they can cause invasive, rapidly spreading infections that confer a high risk of morbidity and mortality, often despite surgical and antifungal therapy. Patients with extensive burn injuries are particularly susceptible to skin and soft-tissue infections with these organisms. Here, we present a case of Lichtheimia infection in a patient with extensive full-thickness burns that required significant and repeated surgical debridement successfully treated with isavuconazole and adjunctive topical amphotericin B washes. We also review the available literature on contemporary antifungal treatment for Lichtheimia species and related Mucorales fungi.

Mycobacterium abscessus Complex Infections in Children: A Review.

PURPOSE OF REVIEW: Infections in children with Mycobacterium abscessus complex represent a particular challenge for clinicians. Increasing incidence of these infections worldwide has necessitated focused attention to improve both diagnostic as well as treatment modalities. Published medical literature was reviewed, with emphasis on material published in the past 5 years. RECENT FINDINGS: Increasing availability of new diagnostic tools, such as matrix-assisted laser desorption ionization-time of flight mass spectrometry and custom PCRs, has provided unique insights into the subspecies within the complex and improved diagnostic certainty. Microbiological review of all recent isolates at the University of Minnesota Medical Center was also conducted, with description of the antimicrobial sensitivity patterns encountered in our center, and compared with those published from other centers in the recent literature. A discussion of conventional antimicrobial treatment regimens, alongside detailed description of the relevant antimicrobials, is derived from recent publications. Antimicrobial therapy, combined with surgical intervention in some cases, remains the mainstay of pediatric care. Ongoing questions remain regarding the transmission mechanics, immunologic vulnerabilities exploited by these organisms in the host, and the optimal antimicrobial regimens necessary to enable a reliable cure. Updated treatment guidelines based on focused clinical studies in children and accounting especially for the immunocompromised children at greatest risk are very much needed.