Community respiratory viruses (CRVs) have been recognized as a potential cause of pneumonia and death among hematopoietic stem cell transplantation (HSCT) recipients and patients with hematologic malignancies. We reviewed the Microbiology Laboratory records dated from July 1, 2000, to June 30, 2002, to identify patients who had respiratory specimens positive for influenza, parainfluenza, respiratory syncytial virus, or picornavirus. We identified 343 infections among patients with underlying hematologic malignancies and HSCT. We collected data on type of disease, age, sex, type of infection, neutrophil and lymphocyte counts, therapy, and outcome. Influenza, parainfluenza, and respiratory syncytial virus accounted for most cases and were approximately equal in frequency. Most infections occurred predominantly among recipients of allogeneic transplants. Infection progressed to pneumonia in 119 patients (35%) and occurred with similar frequency for the 3 viruses. Patients at greatest risk for developing pneumonia included those with leukemia, those aged more than 65 years, and those with severe neutropenia or lymphopenia. Lack of respiratory syncytial virus-directed antiviral therapy (p=0.025) and age (p=0.042) were associated with development of respiratory syncytial virus pneumonia, and an absolute lymphocyte count

Background Aseptic meningitis represents a common diagnostic and management dilemma to clinicians. Objectives To compare the clinical epidemiology, diagnostic evaluations, management, and outcomes between adults and children with aseptic meningitis. Study Design We conducted a retrospective study from January 2005 through September 2010 at 9 Memorial Hermann Hospitals in Houston, TX. Patients age ≥ 2 months who presented with community-acquired aseptic meningitis with a CSF white blood cell count >5 cells/mm3 and a negative Gram stain and cultures were enrolled. Patients with a positive cryptococcal antigen, positive blood cultures, intracranial masses, brain abscesses, or encephalitis were excluded. Results A total of 509 patients were included; 404 were adults and 105 were children. Adults were most likely to be female, Caucasian, immunosuppressed, have meningeal symptoms (headache, nausea, stiff neck, photophobia) and have a higher CSF protein (P<0.05). In contrast, children were more likely to have respiratory symptoms, fever, and leukocytosis (P<0.05). In 410 (81%) patients, the etiologies remained unknown. Adults were more likely to be tested for and to have Herpes simplex virus and West Nile virus while children were more likely to be tested for and to have Enterovirus (P<0.001). The majority of patients were admitted (96.5%) with children receiving antibiotic therapy more frequently (P<0.001) and adults receiving more antiviral therapy (P=0.001). A total of 384 patients (75%) underwent head CT scans and 125 (25%) MRI scans; all were normal except for meningeal enhancement. All patients had a good clinical outcome at discharge. Discussion Aseptic meningitis in adults and children represent a management challenge as etiologies remained unknown for the majority of patients due to underutilization of currently available diagnostic techniques.

Alpha herpes CNS infections due to HSV and VZV infections have similar clinical and laboratory manifestations. ACO was observed more frequently in those patients with comorbidities and an encephalitis presentation.

Giant tailed bacterial viruses, or phages, such as Pseudomonas aeruginosa phage ϕKZ, have long genomes packaged into large, atypical virions. Many aspects of ϕKZ and related phage biology are poorly understood, mostly due to the fact that the functions of the majority of their proteins are unknown. We hypothesized that the Salmonella enterica phage SPN3US could be a useful model phage to address this gap in knowledge. The 240-kb SPN3US genome shares a core set of 91 genes with ϕKZ and related phages, ∼61 of which are virion genes, consistent with the expectation that virion complexity is an ancient, conserved feature. Nucleotide sequencing of 18 mutants enabled assignment of 13 genes as essential, information which could not have been determined by sequence-based searches for 11 genes. Proteome analyses of two SPN3US virion protein mutants with knockouts in 64 and 241 provided new insight into the composition and assembly of giant phage heads. The 64 mutant analyses revealed all the genetic determinants required for assembly of the SPN3US head and a likely head-tail joining role for gp64, and its homologs in related phages, due to the tailless-particle phenotype produced. Analyses of the mutation in 241, which encodes an RNA polymerase β subunit, revealed that without this subunit, no other subunits are assembled into the head, and enabled identification of a “missing” β′ subunit domain. These findings support SPN3US as an excellent model for giant phage research, laying the groundwork for future analyses of their highly unusual virions, host interactions, and evolution.IMPORTANCE In recent years, there has been a paradigm shift in virology with the realization that extremely large viruses infecting prokaryotes (giant phages) can be found in many environments. A group of phages related to the prototype giant phage ϕKZ are of great interest due to their virions being among the most complex of prokaryotic viruses and their potential for biocontrol and phage therapy applications. Our understanding of the biology of these phages is limited, as a large proportion of their proteins have not been characterized and/or have been deemed putative without any experimental verification. In this study, we analyzed Salmonella phage SPN3US using a combination of genomics, genetics, and proteomics and in doing so revealed new information regarding giant phage head structure and assembly and virion RNA polymerase composition. Our findings demonstrate the suitability of SPN3US as a model phage for the growing group of phages related to ϕKZ.