A large simultaneous outbreak of respiratory syncytial virus (RSV) and parainfluenza type 3 (PIV-3) infections occurred on an adult hematology unit. Implementation of enhanced infection control was complicated by cocirculation of the two different viruses, with prolonged viral shedding from infected patients, and placed great pressure on health care staff; of 27 infected hematopoietic stem cell transplant patients, 9 died, and the unit was closed for 2 months. Retrospective molecular investigation of the virus strains involved in the outbreak was performed by analyzing part of the fusion gene of PIV-3 and part of the glycoprotein gene of RSV. Reverse transcription-PCR on nasopharyngeal aspirates from patients infected before and during the simultaneous outbreak generated amplicons for sequence analysis. A single strain of RSV and a single strain of PIV-3 had spread from person to person within the unit; 7 patients were infected with RSV, 22 were infected with PIV-3, and 4 were infected with both viruses. The PIV-3 outbreak had started at the beginning of August 3 months before the RSV outbreak; it had arisen when PIV-3 was introduced from the community by a patient and passed to another patient, who became chronically infected with the identical strain and, in spite of being nursed in isolation, was most likely the source from which widespread infection occurred in November. Had these early cases been linked to a common PIV-3 strain at the time of diagnosis, enhanced infection control precautions might have prevented the eventual extensive spread of PIV-3, making it much easier to deal with the later RSV outbreak.
Thirty unique non-host RNAs were sequenced in the cultivated fungus, Agaricus bisporus, comprising 18 viruses each encoding an RdRp domain with an additional 8 ORFans (non-host RNAs with no similarity to known sequences). Two viruses were multipartite with component RNAs showing correlative abundances and common 3′ motifs. The viruses, all positive sense single-stranded, were classified into diverse orders/families. Multiple infections of Agaricus may represent a diverse, dynamic and interactive viral ecosystem with sequence variability ranging over 2 orders of magnitude and evidence of recombination, horizontal gene transfer and variable fragment numbers. Large numbers of viral RNAs were detected in multiple Agaricus samples; up to 24 in samples symptomatic for disease and 8–17 in asymptomatic samples, suggesting adaptive strategies for co-existence. The viral composition of growing cultures was dynamic, with evidence of gains and losses depending on the environment and included new hypothetical viruses when compared with the current transcriptome and EST databases. As the non-cellular transmission of mycoviruses is rare, the founding infections may be ancient, preserved in wild Agaricus populations, which act as reservoirs for subsequent cell-to-cell infection when host populations are expanded massively through fungiculture.
Effective antiretroviral therapy appeared to limit the effect of urethritis on SVL. When BVL was poorly controlled by antiretroviral therapy, high SVL occurred during gonococcal urethritis, increasing the potential risk of transmitting both wild type and drug resistant strains of HIV-1.
Recent taxonomic developments, based on 16s and 23s rRNA gene sequences, have divided the family Chlamydiaceae into two genera and nine species, of which five have been found to infect humans. Few simple methods are available to detect and identify all species sensitively and specifically. In this study the suitability of the omp2 gene as a target for molecular identification of Chlamydiaceae is demonstrated. Phylogenetic analysis of partial omp2 gene sequences from all nine species agrees with the recently published taxonomic changes based on the ribosomal genes. The use of a family-specific PCR primer pair, which is able to amplify the 5 end of the omp2 gene from all Chlamydiaceae except some Chlamydophila pecorum strains, is described. Identification of all nine species was achieved using restriction fragment length polymorphism analysis with a single enzyme, AluI, confirmed by DNA sequencing. A PCR enzyme-linked oligonucleotide assay was developed which can detect a single chlamydial genome and may be applied to DNA extracts from any specimen or culture for the detection of single or mixed human chlamydial infection.The family Chlamydiaceae has recently been reclassified into two genera and nine species (4). Current human infection by Chlamydiaceae is frequently diagnosed as Chlamydia trachomatis, but less frequently as Chlamydophila pneumoniae (formerly Chlamydia pneumoniae), and rarely as Chlamydophila psittaci (formerly Chlamydia psittaci avian group), Chlamydophila abortus (formerly Chlamydia psittaci abortion group), or Chlamydophila felis (formerly Chlamydia psittaci feline pneumonitis agent). No observation has been made of human infection with Chlamydophila caviae (formerly Chlamydia psittaci guinea pig inclusion conjunctivitis agent), Chlamydophila pecorum (formerly Chlamydia pecorum), Chlamydia suis (formerly porcine Chlamydia trachomatis), or Chlamydophila muridarum (formerly Chlamydia trachomatis of mice).Other than for C. trachomatis, laboratory diagnostic methods are poorly developed and not standardized. Serology is commonly used for diagnosis (6,15), but the immune response to chlamydial infection is often delayed and variable. Microimmunofluorescence, the reference serology method, which was designed for the serotyping of C. trachomatis, is difficult to perform and not fully standardized and does not always correlate with cell culture or nucleic acid detection (8,12,15,16,20). Commercial reagents available for the detection of Chlamydiaceae by direct immunofluorescence (DIF) include the family-specific antibody against the lipopolysaccharide (e.g.,
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