De novo mutations mediate phenotypic switching in an opportunistic human lung pathogen.

Bacteria evolving within human hosts encounter selective tradeoffs that render mutations adaptive in one context and deleterious in another. Here, we report that the cystic fibrosis-associated pathogen Burkholderia dolosa overcomes in-human selective tradeoffs by acquiring successive point mutations that alternate phenotypes. We sequenced the whole genomes of 931 respiratory isolates from two recently infected patients and an epidemiologically-linked, chronically-infected patient. These isolates are contextualized using 112 historical genomes from the same outbreak strain. Within both newly infected patients, diverse parallel mutations that disrupt O-antigen expression quickly arose, comprising 29% and 63% of their B. dolosa communities by 3 years. The selection for loss of O-antigen starkly contrasts with our previous observation of parallel O-antigen-restoring mutations after many years of chronic infection in the historical outbreak. Experimental characterization revealed that O-antigen loss increases uptake in immune cells while decreasing competitiveness in the mouse lung. We propose that the balance of these pressures, and thus whether O-antigen expression is advantageous, depends on tissue localization and infection duration. These results suggest that mutation-driven alternation during infection may be more frequent than appreciated and is underestimated without dense temporal sampling.

Rapid expansion and extinction of antibiotic resistance mutations during treatment of acute bacterial respiratory infections.

Acute bacterial infections are often treated empirically, with the choice of antibiotic therapy updated during treatment. The effects of such rapid antibiotic switching on the evolution of antibiotic resistance in individual patients are poorly understood. Here we find that low-frequency antibiotic resistance mutations emerge, contract, and even go to extinction within days of changes in therapy. We analyzed Pseudomonas aeruginosa populations in sputum samples collected serially from 7 mechanically ventilated patients at the onset of respiratory infection. Combining short- and long-read sequencing and resistance phenotyping of 420 isolates revealed that while new infections are near-clonal, reflecting a recent colonization bottleneck, resistance mutations could emerge at low frequencies within days of therapy. We then measured the in vivo frequencies of select resistance mutations in intact sputum samples with resistance-targeted deep amplicon sequencing (RETRA-Seq), which revealed that rare resistance mutations not detected by clinically used culture-based methods can increase by nearly 40-fold over 5-12 days in response to antibiotic changes. Conversely, mutations conferring resistance to antibiotics not administered diminish and even go to extinction. Our results underscore how therapy choice shapes the dynamics of low-frequency resistance mutations at short time scales, and the findings provide a possibility for driving resistance mutations to extinction during early stages of infection by designing patient-specific antibiotic cycling strategies informed by deep genomic surveillance.

Can We Test Our Way Out of the COVID-19 Pandemic?

Frequent, low-cost, universal testing for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with quarantine of those with a positive result has been suggested as a strategy to address the coronavirus disease 2019 (COVID-19) pandemic in the United States. Specifically, home or community use of tests that use paper strip detection devices, which may have reduced sensitivity for SARS-CoV-2, has been advocated. There are several potential challenges or problems with this strategy, including the limited availability of such tests, consequences of incorrect test results, difficulties with adherence to testing, and the questionable accuracy of such tests for detection of infectious people. Because of these, we think it is premature to strongly advocate for such a testing strategy, as the adverse consequences may outweigh any benefits. High-quality outcome data demonstrating the efficacy of this testing strategy are needed before widespread implementation.

The genome of opportunistic fungal pathogen Fusarium oxysporum carries a unique set of lineage-specific chromosomes.

Fusarium oxysporum is a cross-kingdom fungal pathogen that infects plants and humans. Horizontally transferred lineage-specific (LS) chromosomes were reported to determine host-specific pathogenicity among phytopathogenic F. oxysporum. However, the existence and functional importance of LS chromosomes among human pathogenic isolates are unknown. Here we report four unique LS chromosomes in a human pathogenic strain NRRL 32931, isolated from a leukemia patient. These LS chromosomes were devoid of housekeeping genes, but were significantly enriched in genes encoding metal ion transporters and cation transporters. Homologs of NRRL 32931 LS genes, including a homolog of ceruloplasmin and the genes that contribute to the expansion of the alkaline pH-responsive transcription factor PacC/Rim1p, were also present in the genome of NRRL 47514, a strain associated with Fusarium keratitis outbreak. This study provides the first evidence, to our knowledge, for genomic compartmentalization in two human pathogenic fungal genomes and suggests an important role of LS chromosomes in niche adaptation.

Whole-Genome Sequences of Staphylococcus aureus Isolates from Cystic Fibrosis Lung Infections.

Staphylococcus aureus is an early colonizer in the lungs of individuals with cystic fibrosis (CF), but surprisingly, only a limited number of genomes from CF-associated S. aureus isolates have been sequenced. Here, we present the whole-genome sequences of 65 S. aureus isolates obtained from 50 individuals with CF.

Ceftaroline pharmacokinetics and pharmacodynamics in patients with cystic fibrosis.

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) is a prevalent pathogen in patients with cystic fibrosis (CF) associated with increased morbidity. Ceftaroline fosamil is an intravenous (IV) cephalosporin with activity against MRSA. There are minimal data regarding dosing in the CF population. The objective of this study was to determine the pharmacokinetic and pharmacodynamic profile of IV ceftaroline in patients with CF. METHODS: We conducted a single-center prospective study of children and young adults with CF receiving ceftaroline (15mg/kg IV up to 600mg every 8h) as part of treatment for a CF pulmonary exacerbation between June 2016 and April 2017. Seven patients were enrolled for a total of 10 treatment courses. For each treatment course, up to 8 plasma samples were assayed for ceftaroline using ultra-high performance liquid chromatography with mass spectrometry. Maximum plasma concentration, systemic clearance, and elimination half-life were calculated. The area under the curve (AUC) above the minimum inhibitory concentration (MIC) and the percent time above the MIC (%fT>MIC) were determined for each subject using MICs of 0.5, 1, and 2µg/mL and the measured MIC if available. RESULTS: The mean (SD) age for the 7 patients was 20.3 (8.0) years. Mean (SD) maximum plasma concentration of ceftaroline was 22.7 (9.6) µg/mL, systemic clearance 7.9 (3.3) L/h, and half-life 1.1 (0.4) hours. Using a MIC of 1 µg/mL, accepted as the MIC 90 of MRSA isolates, AUC above MIC mean (SD) was 53.6 (19.5) µg·h/mL, mean (SD) %fT>MIC was 75.7 (10.4), and all subjects had >60%fT>MIC. CONCLUSIONS: In this cohort of CF patients, mean ceftaroline half-life was 1.1h, which is notably lower than the general population. The dosing regimen studied, which exceeds the recommended dosing in the non-CF population, was adequate to achieve >60% time above the MIC in all patients.

Global and local selection acting on the pathogen Stenotrophomonas maltophilia in the human lung.

Bacterial populations diversify during infection into distinct subpopulations that coexist within the human body. Yet, it is unknown to what extent subpopulations adapt to location-specific selective pressures as they migrate and evolve across space. Here we identify bacterial genes under local and global selection by testing for spatial co-occurrence of adaptive mutations. We sequence 552 genomes of the pathogen Stenotrophomonas maltophilia across 23 sites of the lungs from a patient with cystic fibrosis. We show that although genetically close isolates colocalize in space, distant lineages with distinct phenotypes separated by adaptive mutations spread throughout the lung, suggesting global selective pressures. Yet, for one gene (a distant homologue of the merC gene implicated in metal resistance), mutations arising independently in two lineages colocalize in space, providing evidence for location-specific selection. Our work presents a general framework for understanding how selection acts upon a pathogen that colonizes and evolves across the complex environment of the human body.

Association Between Storage Interval and Contamination of Reprocessed Flexible Endoscopes in a Pediatric Gastrointestinal Procedural Unit.

OBJECTIVE The maximum safe storage interval after endoscope reprocessing remains unknown. We assessed the association between storage interval and endoscope contamination to evaluate the need for scope reprocessing prior to use. METHODS We conducted a study in 2 phases. In phase 1, we cultured 9 gastrointestinal (GI) endoscopes that had been stored for at least 7 days since reprocessing. Each scope was cultured in 3 places: external surfaces of hand piece, insertion tube, and internal channels. In phase 2, after reprocessing these scopes, we hung and cultured them prospectively in a similar fashion at 1-, 2-, 4-, 6-, and 8-week intervals without patient use. We defined clinically relevant contamination as >100 colony-forming units per milliliter (CFU/mL). RESULTS In phase 1, median hang time was 69 days (range, 8-555 days). Considering the 27 total cultures, 3 of 27 GI endoscopes (11.1%) had positive cultures, all with nonpathogenic skin flora at ≤100 CFU/mL. Median hang time was not statistically different between scopes with positive and negative cultures (P=.82). In phase 2, 7 of 131 prospective cultures (5.3%) from 6 of 9 GI endoscopes at varying storage intervals were positive, all at ≤100 CFU/mL. At 56 days after reprocessing (the longest storage interval studied), 1 of 24 cultures (4.2%) was positive (100 CFU/mL of Bacillus species from external biopsy/suction ports). CONCLUSIONS No endoscopes demonstrated clinically relevant contamination at hang times ranging from 7 to 555 days, and most scopes remained uncontaminated up to 56 days after reprocessing. Our data suggest that properly cleaned and disinfected GI endoscopes could be stored safely for longer intervals than currently recommended. Infect. Control Hosp. Epidemiol. 2017;38:131-135.

The aetiology of diarrhoea, pneumonia and respiratory colonization of HIV-exposed infants randomized to breast- or formula-feeding.

BACKGROUND: Diarrhoea and pneumonia are common causes of childhood death in sub-Saharan Africa but there are few studies describing specific pathogens. OBJECTIVES: The study aimed to describe the pathogens associated with diarrhoea, pneumonia and oropharyngeal colonization in children born to HIV-infected women (HIV-exposed infants). METHODS: The Mashi Study randomized 1200 HIV-infected women and their infants to breastfeed for 6 months with ZDV prophylaxis or formula-feed with 4 weeks of ZDV. Children were tested for HIV by PCR at 1, 4, 7, 9 and 12 months and by ELISA at 18 months. Pre-defined subsets of children were sampled during episodes of diarrhoea (n = 300) and pneumonia (n = 85). Stool was tested for bacterial pathogens, rotavirus and parasites. Children with pneumonia underwent bacterial blood culture, and testing of nasopharyngeal aspirates for viral pathogens by PCR. Oropharyngeal swabs were collected from a consecutive subset of 561 infants at the routine 3-month visit for bacterial culture. RESULTS: The median age (range) at sampling was 181 days for diarrhoea (0-730) and 140 days for pneumonia (2-551). Pathogens were identified in 55 (18%) children with diarrhoea and 32 (38%) with pneumonia. No differences in pathogens by child HIV status (HIV-infected vs HIV-uninfected) or feeding strategy were identified. Campylobacter was the most common diarrhoeal pathogen (7%). Adenovirus (22%) and other viruses (19%) were the primary pathogens isolated during pneumonias. More formula-fed infants had oropharyngeal colonization by pathogenic Gram-negative bacteria (16.8% vs 6.2%, P = 0.003), which was associated with a non-significant increased risk of pneumonia (OR 2.2, 95% CI 0.8-5.7). CONCLUSION: A trend toward oropharyngeal bacterial colonization was observed in formula-fed infants. Although viruses were most commonly detected during pneumonia, respiratory colonization by Gram-negative bacteria may have contributed to pneumonia in formula-fed infants.

Evaluation of the C6 Lyme Enzyme Immunoassay for the Diagnosis of Lyme Disease in Children and Adolescents.

BACKGROUND: The commercially-available C6 Lyme enzyme immunoassay (EIA) has been approved to replace the standard whole-cell sonicate EIA as a first-tier test for the diagnosis of Lyme disease and has been suggested as a stand-alone diagnostic. However, the C6 EIA has not been extensively studied in pediatric patients undergoing evaluation for Lyme disease. METHODS: We collected discarded serum samples from children and adolescents (aged ≤21 years) undergoing conventional 2-tiered testing for Lyme disease at a single hospital-based clinical laboratory located in an area endemic for Lyme disease. We performed a C6 EIA on all collected specimens, followed by a supplemental immunoblot if the C6 EIA result was positive but the whole-cell sonicate EIA result was negative. We defined a case of Lyme disease as either a clinician-diagnosed erythema migrans lesion or a positive standard 2-tiered serologic result in a patient with symptoms compatible with Lyme disease. We then compared the performance of the C6 EIA alone and as a first-tier test followed by immunoblot, with that of standard 2-tiered serology for the diagnosis of Lyme disease. RESULTS: Of the 944 specimens collected, 114 (12%) were from patients with Lyme disease. The C6 EIA alone had sensitivity similar to that of standard 2-tiered testing (79.8% vs 81.6% for standard 2-tiered testing; P = .71) with slightly lower specificity (94.2% vs 98.8% 2; P < .002). Addition of a supplemental immunoblot improved the specificity of the C6 EIA to 98.6%. CONCLUSIONS: For children and adolescents undergoing evaluation for Lyme disease, the C6 EIA could guide initial clinical decision making, although a supplemental immunoblot should still be performed.

Yield of fungal surveillance cultures in pediatric hematopoietic stem cell transplant patients: a retrospective analysis and survey of current practice.

BACKGROUND: Fungal surveillance cultures (FSCs) have been proposed as predictors for development of invasive fungal disease (IFD) and identifiers of the causative organism, although data supporting these are limited and predate universal initiation of antifungal prophylaxis. We aimed to define the epidemiology of fungal colonization and investigate the utility of FSCs for predicting IFD in recipients of pediatric hematopoietic stem cell transplantation (HSCT). METHODS: FSCs performed from 2007 to 2011 on HSCT patients and laboratory and clinical data were reviewed, and incidence of IFD was determined. Descriptive analyses of culture results were performed to determine the yield of FSCs and their utility. A Web-based survey of national pediatric HSCT providers was undertaken to evaluate current practice and the relevance of our results. RESULTS: Five thousand six hundred eighteen FSCs from nares, throat, and stool from 360 patients were processed. Of these, 14.8% were positive: 30.3% from stool, 13.2% from throat, and 0.9% from nares; 64.4% of patients had >1 positive FSCs. Thirty (8.3%) patients had IFD. IFD occurred in 7.9% and 10.1% of patients with positive and negative FSCs, respectively (P = .25). Antifungal coverage was changed in 69 patients (29.9%) after positive FSC; 8.6% developed IFD (n = 2 of 6 pathogen concordance with FSC) compared with 6.7% (P = .59) who had no treatment change (n = 3 of 11 concordance). The response rate to the survey was 70.8%; 40% of institutions reported performing routine FSC. Twenty-five percent of providers would not change management based on FSC results; overall rating of usefulness of FSCs was low. CONCLUSIONS: Although FSCs are commonly performed for pediatric HSCT patients, they have limited utility for predicting IFD.

Genetic variation of a bacterial pathogen within individuals with cystic fibrosis provides a record of selective pressures.

Advances in sequencing technologies have enabled the identification of mutations acquired by bacterial pathogens during infection. However, it remains unclear whether adaptive mutations fix in the population or lead to pathogen diversification within the patient. Here we study the genotypic diversity of Burkholderia dolosa within individuals with cystic fibrosis by resequencing individual colonies and whole populations from single sputum samples. We find extensive intrasample diversity, suggesting that mutations rarely fix in a patient's pathogen population--instead, diversifying lineages coexist for many years. Under strong selection, multiple adaptive mutations arise, but none of these sweep to fixation, generating lasting allele diversity that provides a recorded signature of past selection. Genes involved in outer-membrane components, iron scavenging and antibiotic resistance all showed this signature of within-patient selection. These results offer a general and rapid approach for identifying the selective pressures acting on a pathogen in individual patients based on single clinical samples.

Targeting pan-resistant bacteria with antibodies to a broadly conserved surface polysaccharide expressed during infection.

BACKGROUND: New therapeutic targets for antibiotic-resistant bacterial pathogens are desperately needed. The bacterial surface polysaccharide poly-ß-(1-6)-N-acetyl-glucosamine (PNAG) mediates biofilm formation by some bacterial species, and antibodies to PNAG can confer protective immunity. By analyzing sequenced genomes, we found that potentially multidrug-resistant bacterial species such as Klebsiella pneumoniae, Enterobacter cloacae, Stenotrophomonas maltophilia, and the Burkholderia cepacia complex (BCC) may be able to produce PNAG. Among patients with cystic fibrosis patients, highly antibiotic-resistant bacteria in the BCC have emerged as problematic pathogens, providing an impetus to study the potential of PNAG to be targeted for immunotherapy against pan-resistant bacterial pathogens. METHODS: The presence of PNAG on BCC was assessed using a combination of bacterial genetics, microscopy, and immunochemical approaches. Antibodies to PNAG were tested using opsonophagocytic assays and for protective efficacy against lethal peritonitis in mice. RESULTS: PNAG is expressed in vitro and in vivo by the BCC, and cystic fibrosis patients infected by the BCC species B. dolosa mounted a PNAG-specific opsonophagocytic antibody response. Antisera to PNAG mediated opsonophagocytic killing of BCC and were protective against lethal BCC peritonitis even during coinfection with methicillin-resistant Staphylococcus aureus. CONCLUSIONS: Our findings raise potential new therapeutic options against PNAG-producing bacteria, including even pan-resistant pathogens.

Parallel bacterial evolution within multiple patients identifies candidate pathogenicity genes.

Bacterial pathogens evolve during the infection of their human host(1-8), but separating adaptive and neutral mutations remains challenging(9-11). Here we identify bacterial genes under adaptive evolution by tracking recurrent patterns of mutations in the same pathogenic strain during the infection of multiple individuals. We conducted a retrospective study of a Burkholderia dolosa outbreak among subjects with cystic fibrosis, sequencing the genomes of 112 isolates collected from 14 individuals over 16 years. We find that 17 bacterial genes acquired nonsynonymous mutations in multiple individuals, which indicates parallel adaptive evolution. Mutations in these genes affect important pathogenic phenotypes, including antibiotic resistance and bacterial membrane composition and implicate oxygen-dependent regulation as paramount in lung infections. Several genes have not previously been implicated in pathogenesis and may represent new therapeutic targets. The identification of parallel molecular evolution as a pathogen spreads among multiple individuals points to the key selection forces it experiences within human hosts.

Influenza and other respiratory virus-related emergency department visits among young children.

BACKGROUND: Influenza and other winter respiratory viruses cause substantial morbidity among children. Previous estimates of the burden of illness of these viruses have neglected to include the emergency department, where a large number of patients seek acute care for respiratory illnesses. This study provides city- and statewide population estimates of the burden of illness attributable to respiratory viruses for children receiving emergency department-based care for respiratory infections during the winter months. METHODS: The number of patients < or = 7 years of age presenting to the emergency department of an urban tertiary care pediatric hospital with acute respiratory infections was estimated by using a classifier based on presenting complaints. The rates of specific viral infections in this population were estimated by using the rates of positivity for respiratory syncytial virus, influenza virus, parainfluenza virus, adenovirus, and enterovirus. Local emergency department market share and US Census data enabled determination of the rates of emergency department visits in the Boston, Massachusetts, area and in Massachusetts. RESULTS: During the 11-year study period, the mean yearly number of patients < or = 7 years of age presenting to the study emergency department during the winter season was 17397. On the basis of the respiratory classifier, the mean number of patients with an acute respiratory infection was 6923, or 398 per 1000 emergency department visits. In the city population, the mean number of emergency department visits for acute respiratory infections was 17906, which is equivalent to 113.9 per 1000 children residing in the city, and in the state population the mean number was 61529, or 94.5 per 1000 children residing in the state. At the state level, 23114 of the visits were for respiratory syncytial virus, 5650 for influenza, 1751 for parainfluenza virus, 2848 for adenovirus, and 798 for enterovirus. For patients 6 to 23 months of age in the state population, there were 19860 emergency department visits for acute respiratory infections, or 168 per 1000 children in this age group, with 6235 visits resulting from respiratory syncytial virus and 2112 resulting from influenza. CONCLUSION: There is a high incidence of emergency department visits for infectious respiratory illnesses among children. This important component of health care use should be included in estimates of the burden of illness attributable to influenza and other winter respiratory viruses.

Validation of syndromic surveillance for respiratory infections.

STUDY OBJECTIVE: A key public health question is whether syndromic surveillance data provide early warning of infectious outbreaks. One cause for skepticism is that biological correlates of the administrative and clinical data used in these systems have not been rigorously assessed. This study measures the value of respiratory data currently used in syndromic surveillance systems to detect respiratory infections by comparing it against criterion standard viral testing within a pediatric population. METHODS: We conducted a longitudinal study with prospective validation in the emergency department (ED) of a tertiary care children's hospital. Children aged 7 years or younger who presented with a respiratory syndrome or who were tested for respiratory syncytial virus (RSV), influenza virus, parainfluenza virus, adenovirus, or enterovirus between January 1993 and June 2004 were included. We assessed the predictive ability of the viral tests by fitting generalized linear models to respiratory syndrome counts. RESULTS: Of 582,635 patient visits, 89,432 (15.4%) were for respiratory syndromes, and of these, 7,206 (8.1%) patients were tested for the viruses of interest. RSV was significantly related to respiratory syndrome counts (adjusted rate ratio [RR] 1.33; 95% confidence interval [CI] 1.04 to 1.71). In multivariate models including all viruses tested, influenza virus was also a significant predictor of respiratory syndrome counts (RR 1.47; 95% CI 1.03 to 2.10). This model accounted for 81.6% of the observed variability in respiratory syndrome counts. CONCLUSION: Respiratory syndromic surveillance data strongly correlate with virologic test results in a pediatric population, providing evidence of the biologic validity of such surveillance systems. Real-time outbreak detection systems relying on syndromic data may be an important adjunct to the current set of public health systems for the detection and surveillance of respiratory infections.

Impact of Burkholderia dolosa on lung function and survival in cystic fibrosis.

RATIONALE: Chronic infection with Burkholderia cepacia complex bacteria in cystic fibrosis is associated with accelerated decline in pulmonary function and increased mortality. Clinical implications of the recently characterized genomovar VI, B. dolosa, are unknown. OBJECTIVES: Characterization of impact of B. dolosa on pulmonary function and mortality in cystic fibrosis. METHODS: We compared patients chronically infected with B. dolosa (n = 31) with unmatched patients with B. multivorans (n = 24) and with age- and sex-matched control subjects without Burkholderia species (n = 58). We analyzed rates of pulmonary function decline (% predicted FEV(1)) using a random effects model assuming segmented linear trends. All available FEV(1) measurements from 5 yr (median, 4.8) before until 2.5 yr (median, 1.5) after the first positive culture for Burkholderia (reference date) were analyzed. Survival was compared using the Kaplan-Meier method and proportional hazards model. MEASUREMENTS AND MAIN RESULTS: Baseline FEV(1) and rate of decline were similar in the cohorts. Decline in FEV(1) after the reference date accelerated in patients with B. dolosa (-2.3 percentage points/yr pre vs. -7.1 post, p = 0.002), but was unchanged in the B. multivorans and control patients (-2.3 vs. -0.8 post, p = 0.38, and -2.1 pre vs. -0.5 post, p = 0.20, respectively). The probability of dying within 18 mo of the reference date was 13, 7, and 3% for B. dolosa, B. multivorans, and control patients, respectively (B. dolosa vs. control hazard ratio, 10.8; 95% confidence interval, 1.3-92.8; p = 0.03). CONCLUSIONS: B. dolosa chronic infection in cystic fibrosis is associated with accelerated loss of lung function and decreased survival.

Pathology of human metapneumovirus infection: insights into the pathogenesis of a newly identified respiratory virus.

Human metapneumovirus (hMPV) is a recently discovered human virus that causes significant respiratory infections. Pathologic features of hMPV infection have not been described. A total of 1257 pediatric respiratory samples submitted for routine clinical virologic testing were additionally tested for hMPV by reverse transcriptase polymerase chain reaction (PCR). Pathology specimens, available in 6 of 53 hMPV-positive patients, were examined by light and electron microscopy and included 6 bronchoalveolar lavage (BAL) and 3 lung biopsy specimens from 6 patients (3 girls and 3 boys) ranging in age from 1 to 16 years. BAL from three patients performed within 4 days of the positive hMPV assay showed epithelial degenerative changes and eosinophilic cytoplasmic inclusions within epithelial cells, multinucleate giant cells, and histiocytes. Inclusions were not seen in three patients with BAL performed = 1 month from the time of their positive assay. Lung biopsy, performed in three patients, all = 1 month from the time of their positive assay, showed chronic airway inflammation and intraalveolar foamy and hemosiderin-laden macrophages; all three patients had an underlying pulmonary/systemic disorder. Our findings delineate the clinicopathologic features in hMPV-infected patients undergoing anatomic sampling, which may provide diagnostic guidance to a practicing pathologist. Further, they contribute toward understanding the pathogenesis of hMPV infection.

Resistance of group B streptococcus to selected antibiotics, including erythromycin and clindamycin.

Resistance of group B streptococcus (GBS) to antibiotics, particularly erythromycin and clindamycin, was studied. Erythromycin resistance was present in 22% of GBS isolates, and these isolates were constitutively resistant, inducibly resistant, or sensitive to clindamycin. Erythromycin and clindamycin MICs were related to the presence of ermA, ermB, or mefA genes.