Public health impact of recombinant zoster vaccine for prevention of herpes zoster in US adults immunocompromised due to cancer.

Individuals who are immunocompromised (IC) due to therapy or underlying disease are at increased risk of herpes zoster (HZ). This study evaluates the public health impact of recombinant zoster vaccine (RZV) relative to no HZ vaccination for the prevention of HZ among adults aged ≥18 years diagnosed with selected cancers in the United States (US). A static Markov model was used to simulate three cohorts of individuals who are IC with cancer (time horizon of 30 years; one-year cycle length): hematopoietic stem cell transplant (HSCT) recipients, patients with breast cancer (BC; a solid tumor example), and patients with Hodgkin's lymphoma (HL; a hematological malignancy example). Cohort sizes reflect the estimated annual incidence of each condition in the US population (19,671 HSCT recipients, 279,100 patients with BC, and 8,480 patients with HL). Vaccination with RZV resulted in 2,297; 38,068; and 848 fewer HZ cases for HSCT recipients, patients with BC, and patients with HL, respectively (each versus no vaccine). Vaccination with RZV also resulted in 422; 3,184; and 93 fewer postherpetic neuralgia cases for HSCT, BC, and HL, respectively. Analyses estimated the quality-adjusted life years gained to be 109, 506, and 17 for HSCT, BC, and HL, respectively. To prevent one HZ case, the number needed to vaccinate was 9, 8, and 10, for HSCT, BC, and HL, respectively. These results suggest RZV vaccination may be an effective option to significantly reduce HZ disease burden among patients diagnosed with selected cancers in the US.

Shingles cases can be prevented by recombinant zoster vaccine (RZV). People who have a weakened immune system (immunocompromised) due to disease or therapy are more likely to develop shingles. For example, shingles occurs in nearly a quarter of patients receiving immunosuppressive treatment for blood cancers. To estimate the public health impact of vaccination against shingles in people who are immunocompromised due to cancer in the United States (US), we used a model to simulate groups with selected types of cancer. The results indicate vaccination with RZV can significantly reduce shingles cases and related complications among these groups in the US.

Cost-Effectiveness of Recombinant Zoster Vaccine for the Prevention of Herpes Zoster in Hematopoietic Stem Cell Transplant Recipients and Other Immunocompromised Adults in the United States.

INTRODUCTION: Immunocompromised (IC) adults are at increased risk of developing herpes zoster (HZ) and HZ-related complications due to therapy or underlying disease. This study evaluated the cost effectiveness of recombinant zoster vaccine (RZV) versus no vaccine for the prevention of HZ in hematopoietic stem cell transplant (HSCT) recipients and other IC adults aged ≥ 18 years in the United States (US). METHODS: A static Markov model simulated cohorts of IC individuals using a 1-year cycle length and 30-year time horizon to estimate the cost effectiveness of RZV. Inputs were sourced from clinical trial results and publicly available sources/literature. Modeled populations included US adult HSCT recipients (base case), patients with human immunodeficiency virus (HIV), patients with breast cancer, patients with Hodgkin's lymphoma, and renal transplant recipients. The model reported societal costs, quality-adjusted life-years (QALYs), and incremental cost-effectiveness ratios (ICERs). Sensitivity and threshold analyses were conducted. RESULTS: In the base case of 19,671 US adult HSCT recipients, RZV resulted in total societal cost savings of US$0.1 million and 109 incremental QALYs versus no vaccine. RZV was a 'dominant strategy' versus no vaccine because vaccination resulted in cost savings with QALY gains. RZV was also cost saving in renal transplant recipients, and cost effective at a willingness-to-pay threshold of US$100,000 per QALY gained in patients with HIV, breast cancer, and Hodgkin's lymphoma, with ICERs of US$33,268, US$67,682, and US$95,972 per QALY gained, respectively, versus no vaccine. CONCLUSIONS: Model results show RZV is potentially cost saving for the prevention of HZ in US adult HSCT recipients and US adults with selected immunocompromising conditions, and cost effective for others, supporting the use of RZV to prevent HZ and HZ-related complications in IC adults.

Epidemiology, Clinical Characteristics, and Outcomes of a Large Cohort of COVID-19 Outpatients in Michigan.

BACKGROUND: Most outpatients with coronavirus disease 2019 (COVID-19) do not initially demonstrate severe features requiring hospitalization. Understanding this population's epidemiological and clinical characteristics to allow outcome anticipation is crucial in healthcare resource allocation. METHODS: Retrospective, multicenter (8 hospitals) study reporting on 821 patients diagnosed with COVID-19 by real-time reverse transcriptase-polymerase chain reaction assay of nasopharyngeal swabs and discharged home to self-isolate after evaluation in emergency departments (EDs) within Beaumont Health System in March, 2020. Outcomes were collected through April 14, 2020, with a minimum of 12 day follow-up and included subsequent ED visit, admission status, and mortality. RESULTS: Of the 821 patients, mean age was 49.3 years (SD 15.7), 46.8% were male and 55.1% were African-American. Cough was the most frequent symptom in 78.2% of patients with a median duration of 3 days (IQR 2-7), and other symptoms included fever 62.1%, rhinorrhea or nasal congestion 35.1% and dyspnea 31.2%. ACEI/ARBs usage was reported in 28.7% patients and 34.0% had diabetes mellitus. Return to the ED for re-evaluation was reported in 19.2% of patients from whom 54.4% were admitted. The patients eventually admitted to the hospital were older (mean age 54.4 vs 48.7 years, p=0.002), had higher BMI (35.4 kg/m2 vs 31.9 kg/m2, p=0.004), were more likely male (58.1% vs 45.4%, p=0.026), and more likely to have hypertension (52.3% vs 29.4%, p<0.001), diabetes mellitus (74.4% vs 29.3%, p<0.001) or prediabetes (25.6% vs 8.4%, p<0.001), COPD (39.5% vs 5.4%, p<0.001), and OSA (36% vs 19%, p<0.001). The overall mortality rate was 1.3%. CONCLUSION: We found that 80.8% of patients did not return to the ED for re-evaluation. Sending patients with COVID-19 home if they experience mild symptoms is a safe approach for most patients and might mitigate some of the financial and staffing pressures on healthcare systems.

A Cost-effectiveness Analysis of an Adjuvanted Subunit Vaccine for the Prevention of Herpes Zoster and Post-herpetic Neuralgia.

BACKGROUND: Herpes zoster (HZ) develops in up to 50% of unvaccinated individuals, accounting for >1 million cases annually in the United States. A live attenuated HZ vaccine (LAV) is Food and Drug Administration approved for those age 50 years or older, though Advisory Committee on Immunization Practices recommendations are only for those age 60 years or older. LAV efficacy is ~70% for persons 50-59 years of age, with lower efficacy in older adults. A new 2-dose adjuvanted subunit vaccine (SUV) has >95% efficacy in persons 50-69 years of age and remains ~90% efficacious in persons vaccinated at age 70 years. METHODS: To estimate the relative cost-effectiveness of SUV, LAV, and no vaccination (NoV) strategies, a Markov model was developed based on published data on vaccine efficacy, durability of protection, quality of life, resource utilization, costs, and disease epidemiology. The perspective was US societal, and the cycle length was 1 year with a lifelong time horizon. SUV efficacy was estimated to wane at the same rate as LAV. Outcomes evaluated included lifetime costs, discounted life expectancy, and incremental cost-effectiveness ratios (ICERs). RESULTS: For individuals vaccinated at age 50 years, the ICER for LAV vs NoV was $118 535 per quality-adjusted life-year (QALY); at age 60 years, the ICER dropped to $42 712/QALY. SUV was more expensive but had better ICERs than LAV. At age 50, the ICER was $91 156/QALY, and it dropped to $19 300/QALY at age 60. CONCLUSIONS: Vaccination with SUV was more cost-effective than LAV in all age groups studied. Vaccination with SUV at age 50 years appears cost-effective, with an ICER <$100 000/QALY.

The Zika virus and pregnancy: evidence, management, and prevention.

OBJECTIVE: To comprehensively review the available evidence and existing consensus reports and guidelines regarding the pregnancy and reproductive implications of the mosquito-transmitted Zika virus (ZIKV) infection. A primary focus was to provide pertinent information to aid clinicians in the management of pregnancies at risk for, exposed to, or with confirmed ZIKV infection. METHOD: An extensive literature review was performed using Pubmed. Practice guidelines and consensus reports were accessed from international, national, and professional organizations' websites. The clinical articles for ZIKV infection testing varied from case reports to small epidemiologic studies. RESULTS: A ZIKV epidemic has been declared in several countries in the Americas. Fifty-two travel-associated ZIKV infection cases have been reported throughout the USA (as of February 10, 2016). The consequences of congenital fetal/newborn ZIKV infection could potentially have devastating consequences including miscarriage, fetal death, and major anomalies such as microcephaly, brain and brain-stem defects, and long-term neurologic sequelae. While not definitive, current evidence suggests the existence of nonvector-borne transmission through sexual activity with an infected male partner. For women at risk for sexual transmission, condom use is advised, especially during pregnancy. CONCLUSION: While ZIKV infection appears to be a mild disease in the general population the potential consequences to the fetus and newborn could be profound. Management guidelines are currently evolving and will be significantly impacted as new evidence develops. It is therefore imperative that obstetric health-care providers keep abreast of this rapidly evolving information landscape that has so far characterized this outbreak.

Daptomycin: another novel agent for treating infections due to drug-resistant gram-positive pathogens.

Daptomycin is a novel cyclic lipopeptide antibiotic that provides rapid bactericidal activity against gram-positive pathogens in vitro, including methicillin-susceptible Staphylococcus aureus, methicillin-resistant S. aureus, vancomycin-resistant S. aureus, penicillin-resistant Streptococcus pneumoniae, and ampicillin- and vancomycin-resistant enterococci. The United States Food and Drug Administration recently approved daptomycin for treatment of complicated skin and skin-structure infections. Its efficacy in the treatment of more-serious infections (e.g., staphylococcal bacteremia) is under investigation. As an intravenous agent that is administered once per day, it offers a convenient regimen for therapy that is continued after discharge, with a side effect profile that appears minimal and manageable. Spontaneous acquisition of resistance in vitro is rare, and hopefully this characteristic will extrapolate into the clinical setting. The rapid bactericidal activity, low potential for resistance, and promising safety profile associated with this agent will make it a useful addition to our growing armamentarium of antibiotics active against gram-positive pathogens.

Prevalence and risk factors associated with vancomycin-resistant Staphylococcus aureus precursor organism colonization among patients with chronic lower-extremity wounds in Southeastern Michigan.

BACKGROUND: Of the 13 US vancomycin-resistant Staphylococcus aureus (VRSA) cases, 8 were identified in southeastern Michigan, primarily in patients with chronic lower-extremity wounds. VRSA infections develop when the vanA gene from vancomycin-resistant enterococcus (VRE) transfers to S. aureus. Inc18-like plasmids in VRE and pSK41-like plasmids in S. aureus appear to be important precursors to this transfer. OBJECTIVE: Identify the prevalence of VRSA precursor organisms. DESIGN: Prospective cohort with embedded case-control study. PARTICIPANTS: Southeastern Michigan adults with chronic lower-extremity wounds. METHODS: Adults presenting to 3 southeastern Michigan medical centers during the period February 15 through March 4, 2011, with chronic lower-extremity wounds had wound, nares, and perirectal swab specimens cultured for S. aureus and VRE, which were tested for pSK41-like and Inc18-like plasmids by polymerase chain reaction. We interviewed participants and reviewed clinical records. Risk factors for pSK41-positive S. aureus were assessed among all study participants (cohort analysis) and among only S. aureus-colonized participants (case-control analysis). RESULTS: Of 179 participants with wound cultures, 26% were colonized with methicillin-susceptible S. aureus, 27% were colonized with methicillin-resistant S. aureus, and 4% were colonized with VRE, although only 17% consented to perirectal culture. Six participants (3%) had pSK41-positive S. aureus, and none had Inc18-positive VRE. Having chronic wounds for over 2 years was associated with pSK41-positive S. aureus colonization in both analyses. CONCLUSIONS: Colonization with VRSA precursor organisms was rare. Having long-standing chronic wounds was a risk factor for pSK41-positive S. aureus colonization. Additional investigation into the prevalence of VRSA precursors among a larger cohort of patients is warranted.

Is there a clinical association of vancomycin MIC creep, agr group II locus, and treatment failure in MRSA bacteremia?

BACKGROUND: The association of vancomycin treatment failure with minimum inhibitory concentration (MIC) creep is concerning, as most isolates are still considered to be in the susceptible range. Several studies have suggested that the accessory gene regulator (agr) group II polymorphism is predictive of vancomycin treatment failure. We assessed the associations between increased vancomycin MIC, agr group II locus, and vancomycin treatment failure in Methicillin-resistant Staphylococcus aureus (MRSA) bacteremias. METHODS: MRSA isolates from 99 inpatient bacteremias were studied. Susceptibility testing was conducted by an automated method (MicroScan) and by the gradient diffusion method (E-test). Vancomycin MICs were stratified into 3 groups for analysis: MIC ≤ 1, MIC > 1 but ≤ 2, and MIC >2 µg/mL. Strains were typed by repetitive-polymerase chain reaction analysis and the agr locus was identified by multiplex polymerase chain reaction. Failure of vancomycin treatment was defined as persistent bacteremia after 72 hours, death at 30 days, or treatment change due to clinical failure. RESULTS: Among 99 bacteremic patients, there were 82 agr group II and 15 agr group I isolates. There was no relationship between higher vancomycin MICs and isolate agr II loci (42 of 82) (P=0.59). Earlier vancomycin exposure was significantly associated with increased MIC (P=0.03). Vancomycin treatment failure was observed in 12 patients: 3 required an alternate regimen, 4 had persistent positive cultures, and 5 whose deaths were attributable to MRSA infection. Survival in agr group II was 57 of 82 (69%) versus agr group I in which it was 14 of 15 (93%), (P=0.06). CONCLUSIONS: We did not identify any significant association between MIC creep and vancomycin failure or between higher vancomycin MICs and agr group II. However, a higher mortality was seen in agr group II than agr group I.

Early colectomy may be associated with improved survival in fulminant Clostridium difficile colitis: an 8-year experience.

BACKGROUND: We hypothesized that colectomy for fulminant Clostridium difficile colitis (CDC) before organ failure would be associated with decreased mortality. METHODS: Data were retrospectively collected on patients operated on for CDC between 2000 and 2007. Variables examined included age, sex, immunodeficiency, recurrent CDC, vasopressor requirement, acute respiratory failure, acute renal failure, white blood cell count, and stress ulcer prophylaxis. Univariate and multivariate analyses were performed to identify predictors of mortality. RESULTS: During this period, 6,841 patients were diagnosed with CDC and 69 patients underwent surgery. Independent predictors of mortality were age >65 years (odds ratio [OR] 6.8, confidence interval [CI] 1.4-32.3, P = .016), acute respiratory failure (OR 5.4, CI 1.6-18.1, P = .007), and acute renal failure (OR 3.8, CI 1.1-13.1, P = .035). CONCLUSIONS: Colectomy before the development of organ failure is associated with decreased mortality in patients with fulminant CDC, especially in those >65 years old.

daptomycin activity against Staphylococcus aureus following vancomycin exposure in an in vitro pharmacodynamic model with simulated endocardial vegetations.

Recently, the emergence of reduced susceptibility to daptomycin has been linked to the reduced vancomycin susceptibility that occurs after vancomycin exposure in Staphylococcus aureus in vivo and in vitro. This study evaluated this propensity in clinical isolates of S. aureus using an in vitro pharmacokinetic/pharmacodynamic model with simulated endocardial vegetations over 8 days. Five clinical isolates (four methicillin-resistant S. aureus isolates and one methicillin-susceptible S. aureus [MSSA] isolate), all of which were reported to have become nonsusceptible to daptomycin, were evaluated. The following regimens were evaluated: vancomycin 1 g every 12 h for 4 days followed by daptomycin 6 mg/kg of body weight daily for 4 days and daptomycin 6 mg/kg daily for 8 days. If nonsusceptibility was detected, the following regimens were evaluated: no treatment for 4 days followed by daptomycin 6 mg/kg daily for 4 days, vancomycin 1 g every 12 h for 4 days followed by daptomycin 10 mg/kg daily for 4 days, and daptomycin 10 mg/kg daily for 8 days. The emergence of daptomycin nonsusceptibility (12- to 16-fold MIC increase) was detected only with the MSSA isolate with daptomycin 6 mg/kg daily for 4 days after vancomycin exposure. However, the bactericidal activity of daptomycin was maintained and the MIC increases of these isolates, which had no mprF or yycG mutations, were unstable to serial passage on antibiotic-free agar. Subsequent regimens did not demonstrate nonsusceptibility to daptomycin. These findings suggest that reduced daptomycin susceptibility can be a strain-specific and unstable event. Further evaluation of the susceptibility relationship between daptomycin and vancomycin is necessary to understand the factors involved and their clinical significance.