Melanie A. Fisher

Measurement of Airborne Influenza Virus in a Hospital Emergency Department

Size-fractionated aerosol particles were collected in a hospital emergency department to test for airborne influenza virus. Using real-time polymerase chain reaction, we confirmed the presence of airborne influenza virus and found that 53% of detectable influenza virus particles were within the respirable aerosol fraction. Our results provide evidence that influenza virus may spread through the airborne route.

Measurements of Airborne Influenza Virus in Aerosol Particles from Human Coughs

Influenza is thought to be communicated from person to person by multiple pathways. However, the relative importance of different routes of influenza transmission is unclear. To better understand the potential for the airborne spread of influenza, we measured the amount and size of aerosol particles containing influenza virus that were produced by coughing. Subjects were recruited from patients presenting at a student health clinic with influenza-like symptoms. Nasopharyngeal swabs were collected from the volunteers and they were asked to cough three times into a spirometer. After each cough, the cough-generated aerosol was collected using a NIOSH two-stage bioaerosol cyclone sampler or an SKC BioSampler. The amount of influenza viral RNA contained in the samplers was analyzed using quantitative real-time reverse-transcription PCR (qPCR) targeting the matrix gene M1. For half of the subjects, viral plaque assays were performed on the nasopharyngeal swabs and cough aerosol samples to determine if viable virus was present. Fifty-eight subjects were tested, of whom 47 were positive for influenza virus by qPCR. Influenza viral RNA was detected in coughs from 38 of these subjects (81%). Thirty-five percent of the influenza RNA was contained in particles >4 µm in aerodynamic diameter, while 23% was in particles 1 to 4 µm and 42% in particles <1 µm. Viable influenza virus was detected in the cough aerosols from 2 of 21 subjects with influenza. These results show that coughing by influenza patients emits aerosol particles containing influenza virus and that much of the viral RNA is contained within particles in the respirable size range. The results support the idea that the airborne route may be a pathway for influenza transmission, especially in the immediate vicinity of an influenza patient. Further research is needed on the viability of airborne influenza viruses and the risk of transmission.

Distribution of Airborne Influenza Virus and Respiratory Syncytial Virus in an Urgent Care Medical Clinic

BACKGROUND Considerable controversy exists with regard to whether influenza virus and respiratory syncytial virus (RSV) are spread by the inhalation of infectious airborne particles and about the importance of this route, compared with droplet or contact transmission. METHODS Airborne particles were collected in an urgent care clinic with use of stationary and personal aerosol samplers. The amounts of airborne influenza A, influenza B, and RSV RNA were determined using real-time quantitative polymerase chain reaction. Health care workers and patients participating in the study were tested for influenza. RESULTS Seventeen percent of the stationary samplers contained influenza A RNA, 1% contained influenza B RNA, and 32% contained RSV RNA. Nineteen percent of the personal samplers contained influenza A RNA, none contained influenza B RNA, and 38% contained RSV RNA. The number of samplers containing influenza RNA correlated well with the number and location of patients with influenza (r= 0.77). Forty-two percent of the influenza A RNA was in particles < or = 4.1 microm in aerodynamic diameter, and 9% of the RSV RNA was in particles < or = 4.1 microm. CONCLUSIONS Airborne particles containing influenza and RSV RNA were detected throughout a health care facility. The particles were small enough to remain airborne for an extended time and to be inhaled deeply into the respiratory tract. These results support the possibility that influenza and RSV can be transmitted by the airborne route and suggest that further investigation of the potential of these particles to transmit infection is warranted.

Effect of High-Dose Vitamin C on the Steady-State Pharmacokinetics of the Protease Inhibitor Indinavir in Healthy Volunteers

Study Objective. To determine whether daily high‐dose vitamin C alters the steady‐state pharmacokinetics of indinavir, a protease inhibitor indicated for treatment of the human immunodeficiency virus type 1.

Pyramidal tract deficits and polyneuropathy in hyperthyroidism. Combination clinically mimicking amyotrophic lateral sclerosis

Generalized weakness, intermittent dysphagia, and a 40-pound weight loss developed in an elderly man over a six-month period. Examination revealed weakness, atrophy and fasciculations of extremity musculature, pseudobulbar speech, hyperactive upper extremity reflexes, and extensor toe signs without sensory loss. Results of electrodiagnostic studies were consistent with an axonal polyneuropathy. Endocrinologic results were compatible with hyperthyroidism. Radioiodine therapy resulted in resolution of clinical neurologic symptoms and signs within seven months. This case illustrates a previously undescribed concurrence of hyperthyroid associated polyneuropathy and pyramidal tract dysfunction that led to an initial clinical diagnosis of amyotrophic lateral sclerosis.

Infrequent occurrence of amphotericin B lipid complex-associated nephrotoxicity in various clinical settings at a university hospital: A retrospective study

BACKGROUND Lipid-based formulations of amphotericin B (AMB) have been shown to significantly lessen the occurrence of nephrotoxicity associated with the conventional form of AMB. A MEDLINE search of literature published from 1983 to 2002, using the search terms amphotericin B and nephrotoxicity, identified only 1 large, randomized, prospective trial that has tried to compare the nephrotoxicity rates among lipid-based AMB formulations. Using the nephrotoxicity surrogate marker of doubling of serum creatinine (SCr) level, the investigators reported a high rate of AMB lipid complex (ABLC)-associated nephrotoxicity (42.3%). However, enrollment in that study was limited to only febrile neutropenic patients. OBJECTIVE This retrospective study estimated the rate of ABLC-associated nephrotoxicity in various clinical settings at a university hospital and compared that rate with previously reported rates of nephrotoxicity. METHODS Data from adult neutropenic and nonneutropenic patients receiving ABLC were collected and the degree of nephrotoxicity was determined using 2 definitions: (1) doubling of baseline SCr level using the peak value within the first 7 days, and (2) end-of-therapy doubling of baseline SCr level using the end-of-therapy value. RESULTS Data from 33 patients (20 men, 13 women; mean age, 48.6 years) were collected. Using these definitions of ABLC-associated nephrotoxicity, only 2 cases (6.1%) were observed. This rate was significantly below the 42.3% rate reported in the only large published study (95% CI, 1.7-19.6; P < 0.001). The median change in SCr level was 0.1 mg/dL (range, -1.1 to 4.3 mg/dL). Rates of change were higher in patients who died during hospitalization, but the difference was not significant. Use of concomitant nephrotoxic agents did not account for significant changes in SCr level. CONCLUSIONS Data from this study suggest that ABLC infrequently causes clinically significant nephrotoxicity. Therefore, when formulary decisions are made in the selection of a drug for use in various clinical settings, earlier data derived from a single study in febrile neutropenic patients that suggested a significantly higher rate of nephrotoxicity should be interpreted cautiously. Larger trials with more diverse patient populations are needed to better characterize institutional rates of ABLC-associated nephrotoxicity and to aid formulary decision makers.

Catheter-related bloodstream infection caused by Mycobacterium mageritense.

Mycobacterium mageritense is an uncommon cause of catheter-related bacteremia ([1][1], [4][2]). We report a 26-year-old pregnant woman who presented with fever for 3 weeks. A tunneled central venous catheter (CVC) had been placed due to hyperemesis. The patient did not have any immunocompromised

The African Eye Worm: A Case Report and Review

Loiasis, caused by the filarial nematode Loa loa, is often asymptomatic but frequently manifests as episodic angioedema and periocular migration of adult worms. Hence also known as the eye worm.(1) It is rarely encountered in the United States among travelers and immigrants. This report describes a case of loiasis in a Cameroonian student seen at a US university clinic.

Needle exchange programs for the prevention of hepatitis C virus infection in people who inject drugs: a systematic review with meta-analysis

BackgroundPrevious research on the effectiveness of needle exchange programs (NEP) in preventing hepatitis C virus (HCV) in people who inject drugs (PWID) has shown mixed findings. The purpose of this study was to use the meta-analytic approach to examine the association between NEP use and HCV prevention in PWIDs.MethodsStudy inclusion criteria were (1) observational studies, (2) PWIDs, (3) NEP use, (4) HCV status ascertained by serological testing, (5) studies published in any language since January 1, 1989, and (6) data available for measures of association. Studies were located by searching four electronic databases and cross-referencing. Study quality was assessed using the Newcastle Ottawa (NOS) scale. A ratio measure of association was calculated for each result from cohort or case–control studies and pooled using a random effects model. Odds ratio (OR) and hazard ratio (HR) models were analyzed separately. Results were considered statistically significant if the 95% confidence interval (CI) did not cross 1. Heterogeneity was estimated using Q and I2 with alpha values for Q ≤ 0.10 considered statistically significant.ResultsOf the 555 citations reviewed, 6 studies containing 2437 participants were included. Studies had an average NOS score of 7 out of 9 (77.8%) stars. Concerns over participant representativeness, unclear adjustments for confounders, and bias from participant nonresponse and loss to follow-up were noted. Results were mixed with the odds ratio model indicating no consistent association (OR, 0.51, 95% CI, 0.05–5.15), and the hazard ratio model indicating a harmful effect (HR, 2.05, 95% CI, 1.39–3.03). Substantial heterogeneity (p ≤ 0.10) and moderate to large inconsistency (I2 ≥ 66%) were observed for both models.ConclusionsThe impact of NEPs on HCV prevention in PWIDs remains unclear. There is a need for well-designed research studies employing standardized criteria and measurements to clarify this issue.Trial registrationPROSPERO CRD42016035315

An assessment of influenza vaccination among health profession students.

Health profession students work in close proximity to patients and could be a source of nosocomial influenza. We studied the proportion of health profession students presenting for immunization at an influenza immunization campaign. This assessment is useful to guide future campaigns as we prepare for pandemic influenza.