Emerging Infectious Diseases

Online ISSN: 1080-6040
Publications
Specimens chosen for more detailed virus genetic analysis, Saudi Arabia and Yemen 
Article
The first confirmed Rift Valley fever outbreak outside Africa was reported in September 2000, in the Arabian Peninsula. As of February 2001, a total of 884 hospitalized patients were identified in Saudi Arabia, with 124 deaths. In Yemen, 1,087 cases were estimated to have occurred, with 121 deaths. Laboratory diagnosis of Rift Valley fever virus (RVFV) infections included virus genetic detection and characterization of clinical specimens by reverse transcription-polymerase chain reaction, in addition to serologic tests and virus isolation. Genetic analysis of selected regions of virus S, M, and L RNA genome segments indicated little genetic variation among the viruses associated with disease. The Saudi Arabia and Yemen viruses were almost identical to those associated with earlier RVF epidemics in East Africa. Analysis of S, M, and L RNA genome segment sequence differences showed similar phylogenetic relationships among these viruses, indicating that genetic reassortment did not play an important role in the emergence of this virus in the Arabian Peninsula. These results are consistent with the recent introduction of RVFV into the Arabian Peninsula from East Africa.
 
Article
During the winter of 2001-02, influenza AH1N2 viruses were detected for the first time in humans in the U.K. The H1N2 viruses co-circulated with H3N2 viruses and a very small number of H1N1 viruses and were isolated in the community and hospitalized patients, predominantly from children <15 years of age. Characterization of H1N2 viruses indicated that they were antigenically and genetically homogeneous, deriving the hemagglutinin (HA) gene from recently circulating A/New Caledonia/20/99-like H1N1 viruses, whereas the other seven genes originated from recently circulating H3N2 viruses. Retrospective reverse transcription-polymerase chain reaction analysis of influenza A H1 viruses isolated in the U.K. during the previous winter identified a single H1N2 virus, isolated in March 2001, indicating that H1N2 viruses did not widely circulate in the U.K. before September 2001. The reassortment event is estimated to have occurred between 1999 and early 2001, and the emergence of H1N2 viruses in humans reinforces the need for frequent surveillance of circulating viruses.
 
Article
To the Editor: Rates and severity of Clostridium difficile infection (CDI) have recently increased worldwide and correlate with dissemination of hypervirulent epidemic strains designated PCR-ribotype 027. CDI caused by this PCR-ribotype is characterized by strong toxin A and B production, presence of binary toxin genes, and, usually, a high level of resistance to fluoroquinolones (1).
 
Figure. Results of PCR ribotyping of Clostridium diffi cile 027 strains from Chile. M indicates the 100-bp DNA ladder; lane 2, R20291; lane 2, PUC47; lane 3, PUC51. A) PCR ribotyping of C. diffi cile isolates. PCR results show that that the band pattern of the ribosomal intergenic regions of strains PUC47 and PUC51 are similar to those of the reference (epidemic) strain R20291. B) Cluster analysis of strains PUC47, PUC51, and the epidemic strain 027 R20291 shows >99% similarity and that they belong to the same epidemic clade. Scale bar indicates percent identity.  
Article
TO THE EDITOR: The increased severity of Clostridium difficile infection is primarily attributed to the appearance of an epidemic strain characterized as PCR ribotype 027 (1). The only report that identified epidemic C. difficile ribotype 027 in an American country outside of North America comes from Costa Rica, raising the possibility that strains 027 might also be present in other countries of Latin America (2). Several studies between 2001 and 2009 have been conducted in South American countries to detect the incidence of C. difficile infection in hospitalized patients, but they did not identify which C. difficile strains were causing these infections (3).
 
Article
Outbreaks due to Clostridium difficile polymerase chain reaction (PCR) ribotype 027, toxinotype III, were detected in 7 hospitals in the Netherlands from April 2005 to February 2006. One hospital experienced at the same time a second outbreak due to a toxin A-negative C. difficile PCR ribotype 017 toxinotype VIII strain. The outbreaks are difficult to control.
 
Article
During the 2003-04 influenza season, 17 cases of Staphylococcus aureus community-acquired pneumonia (CAP) were reported from 9 states; 15 (88%) were associated with methicillin-resistant S. aureus (MRSA). The median age of patients was 21 years; 5 (29%) had underlying diseases, and 4 (24%) had risk factors for MRSA. Twelve (71%) had laboratory evidence of influenza virus infection. All but 1 patient, who died on arrival, were hospitalized. Death occurred in 5 (4 with MRSA). S. aureus isolates were available from 13 (76%) patients (11 MRSA). Toxin genes were detected in all isolates; 11 (85%) had only genes for Panton-Valentine leukocidin. All isolates had community-associated pulsed-field gel electrophoresis patterns; all MRSA isolates had the staphylococcal cassette chromosome mec type IVa. In communities with a high prevalence of MRSA, empiric therapy of severe CAP during periods of high influenza activity should include consideration for MRSA.
 
Map of France, showing spatial distribution of Yersinia pseudotuberculosis infections during the winter of 2004–05. Black circles, patients’ residences; open circles, cities with medical laboratories that stated that they had not isolated any Y. pseudotuberculosis from clinical specimens. 
County distribution, France, of Yersinia pseudotuberculosis isolated from human blood and reported to the Yersinia National Reference Laboratory over the 16 years preceding the winter of 2004–05. The number of isolates is represented by proportionally sized circles arbitrarily located at the center of the counties. 
Article
Cases of Yersinia pseudotuberculosis infection increased in France during the winter of 2004-05 in the absence of epidemiologic links between patients or strains. This increase represents transient amplification of a pathogen endemic to the area and may be related to increased prevalence of the pathogen in rodent reservoirs.
 
Demographic features of patients with adamantine-resistant or -susceptible influenza A, 2004-05 season* 
Figure. Results of patient recruitment and infl uenza cultures. *One isolate was not characterized. 
Article
Adamantane-resistant influenza A is an emerging problem, but infections caused by resistant and susceptible viruses have not been compared. We identified adamantane resistance in 47% of 152 influenza A virus (H3N2) isolates collected during 2005. Resistant and susceptible viruses caused similar symptoms and illness duration. The prevalence of resistance was highest in children.
 
Article
Virtually all US military basic trainees receive seasonal influenza vaccine. Surveillance data collected from December 2005 through March 2006 were evaluated to estimate effectiveness of the influenza vaccine at 6 US military basic training centers. Vaccine effectiveness against laboratory-confirmed influenza was 92% (95% confidence interval 85%-96%).
 
Article
Defined T cell epitopes for West Nile (WN) virus may be useful for developing subunit vaccines against WN virus infection and diagnostic reagents to detect WN virus-specific immune response. We applied a bioinformatics (EpiMatrix) approach to search the WN virus NY99 genome for HLA B*07 restricted cytotoxic T cell (CTL) epitopes. Ninety-five of 3,433 WN virus peptides scored above a predetermined cutoff, suggesting that these would be likely to bind to HLA B*07 and would also be likely candidate CTL epitopes. Compared with other methods for genome mapping, derivation of these ligands was rapid and inexpensive. Major histocompatibility complex ligands identified by this method may be used to screen T cells from WN virus-exposed persons for cell-mediated response to WN virus or to develop diagnostic reagents for immunopathogenesis studies and epidemiologic surveillance.
 
Phylogenetic reconstruction of the H1 genes of infl uenza viruses A (H1N1) in Norway, 2007-08 season. The analysis was performed on an alignment spanning positions 84-1054 of viral RNA segment 4. Pairwise distances were calculated by using the Kimura 2-parameter model with a transition:transversion ratio of 2.0; the phylogenetic tree was constructed by the neighbor-joining method, as implemented in the programs DNADIST and NEIGHBOR in the PHYLIP package (14,15). Published sequences were obtained from the Infl uenza Sequence Database, Los Alamos National Laboratory (16). Boldface indicates viruses from the 2007-08 infl uenza season in Norway; red indicates oseltamivir-resistant viruses; blue, susceptible viruses. New sequences presented in this analysis have been deposited in GenBank (accession nos. CY036664-CY036694).
Reported associations for patients infected with oseltamivir-resistant or oseltamivir-susceptible influenza virus A (H1N1), 2007-08 influenza season, Norway*
Proportion of oseltamivir-resistant in fl uenza viruses A (H1N1) in the 2007–08 in fl uenza season in Norway, by county of sampling. The total number of samples analyzed for each county is given inside each county. 
Article
In Norway in January 2008, unprecedented levels of oseltamivir resistance were found in 12 of 16 influenza viruses A (H1N1) tested. To investigate the epidemiologic and clinical characteristics of these viruses, we used sequence analysis to test all available subtype H1N1 viruses from the 2007-08 season for resistance. Questionnaires from physicians provided information on predisposing diseases, oseltamivir use, symptoms, and complications. Clinical data were obtained for 265 patients. In total, 183 (67.3%) of 272 viruses were oseltamivir resistant. Resistance was not associated with prior use of antiviral drugs. Symptoms and hospitalization rates did not differ for patients infected with a resistant or a susceptible virus. Oseltamivir-resistant influenza viruses A (H1N1) did not show diminished capability to spread in the absence of selective pressure. The ability of these viruses to sustain their fitness and spread among persons should be considered when shaping future strategies for treating and preventing seasonal and pandemic influenza.
 
Total number of in fl uenza virus detections, by type and subtype and by week, Europe, winter 2007–08. 
Total in fl uenza A viruses subtyped as H1N1 and number of oseltamivir-resistant or oseltamivir-sensitive viruses among the subset of in fl uenza viruses A (H1N1) for which oseltamivir susceptibility was determined, by week, Europe, winter 2007–08. 
Weighted average prevalence of oseltamvir-resistant infl uenza viruses A (H1N1), Europe, winter 2007-08. The light gray region indicates the 95% confi dence interval.
Phylogenetic comparisons of the hemagglutinin (A) and neuraminidase (B) genes of infl uenza viruses A (H1N1). Sequences of oseltamivir-resistant viruses, possessing the H275Y (H274Y in N2 numbering) mutation are in boldface; vaccine strains are in italics. Common amino acid changes that distinguish clades 1 and 2 and subgroups of clade 2 are shown. Scale bars indicate 0.01 nucleotide substitutions per site.
Article
In Europe, the 2007-08 winter season was dominated by influenza virus A (H1N1) circulation through week 7, followed by influenza B virus from week 8 onward. Oseltamivir-resistant influenza viruses A (H1N1) (ORVs) with H275Y mutation in the neuraminidase emerged independently of drug use. By country, the proportion of ORVs ranged from 0% to 68%, with the highest proportion in Norway. The average weighted prevalence of ORVs across Europe increased gradually over time, from near 0 in week 40 of 2007 to 56% in week 19 of 2008 (mean 20%). Neuraminidase genes of ORVs possessing the H275Y substitution formed a homogeneous subgroup closely related to, but distinguishable from, those of oseltamivir-sensitive influenza viruses A (H1N1). Minor variants of ORVs emerged independently, indicating multiclonal ORVs. Overall, the clinical effect of ORVs in Europe, measured by influenza-like illness or acute respiratory infection, was unremarkable and consistent with normal seasonal activity.
 
Article
We conducted a population-based study in Manitoba, Canada, to investigate whether use of inactivated trivalent influenza vaccine (TIV) during the 2008-09 influenza season was associated with subsequent infection with influenza A(H1N1)pdm09 virus during the first wave of the 2009 pandemic. Data were obtained from a provincewide population-based immunization registry and laboratory-based influenza surveillance system. The test-negative case-control study included 831 case-patients with confirmed influenza A(H1N1)pdm09 virus infection and 2,479 controls, participants with test results negative for influenza A and B viruses. For the association of TIV receipt with influenza A(H1N1)pdm09 virus infection, the fully adjusted odds ratio was 1.0 (95% CI 0.7-1.4). Among case-patients, receipt of 2008-09 TIV was associated with a statistically nonsignificant 49% reduction in risk for hospitalization. In agreement with study findings outside Canada, our study in Manitoba indicates that the 2008-09 TIV neither increased nor decreased the risk for infection with influenza A(H1N1)pdm09 virus.
 
Article
In recent years, population and evolutionary biologists have questioned the traditional view that parasite-mediated morbidity and mortality¿virulence¿is a primitive character and an artifact of recent associations between parasites and their hosts. A number of hypotheses have been proposed that favor virulence and suggest that it will be maintained by natural selection. According to some of these hypotheses, the pathogenicity of HIV, Vibrio cholerae, Mycobacterium tuberculosis,theShigella,as well as Plasmodium falciparum,and many other microparasites, are not only maintained by natural selection, but their virulence increases or decreases as an evolutionary response to changes in environmental conditions or the density and/or behavior of the human population. Other hypotheses propose that the virulence of microparasites is not directly favored by natural selection; rather, microparasite-mediated morbidity and mortality are either coincidental to parasite-expressed characters (virulence determinants that evolved for other functions) or the product of short-sighted evolution in infected hosts. These hypotheses for the evolution and maintenance of microparasite virulence are critically reviewed, and suggestions are made for testing them experimentally.
 
Genetic organization of the antibiotic-resistance gene cluster of SGI1 of Salmonella enterica serotype Typhimurium DT 104. DR-L and DR-R are the left and right direct repeats, respectively, bracketing SGI1. Polymerase chain reactions (PCRs) used to assess the genetic organization of the antibiotic-resistance genes (PCRs floR, A, B, C, D, and E) and the SGI1 junctions to the chromosome (PCRs LJ and RJ for left and right junctions, respectively) are indicated. Abbreviations for restriction sites: X, XbaI; H, HindIII; Xh, XhoI.  
Article
We have identified Salmonella genomic island I (SGI1) in an isolate of Salmonella enterica serotype Paratyphi B. This antibiotic-resistance gene cluster, which confers multidrug resistance, has been previously identified in S. enterica serotype Typhimurium phage types DT 104 and DT 120 and in S. enterica serotype Agona.
 
Virologic and clinical follow-up of immunocompromised patient infected with Pavia strain (Pav-5) showing the kinetics of enterovirus 104 (EV-104) and respiratory syncytial virus (RSV) viral loads, along with respiratory symptoms. Starting on day 90 after transplantation, the patient's clinical symptoms began to disappear in the presence of a substantially unchanged EV-104 viral load in respiratory secretions. Ct, cycle threshold; HSC, hematopoietic stem cells. 
Article
In an epidemiologic investigation of respiratory infections in Italy, October 2008-September 2009, we tested samples from patients for respiratory viruses. Human enterovirus genotype EV-104 (identified in Switzerland) was found in 3 immunocompromised and 2 immunocompetent patients. EV-104 is closely related to human rhinoviruses; thus, both types of viruses should be sought in respiratory syndromes.
 
Antimicrobial susceptibility of Salmonella enterica serotype Typhimurium definitive phage type (DT) 12 and DT 120 isolates, England and Wales, 1991–2000. A, S. Typhimurium DT 12; B, S. Typhimurium DT 120. Clear bar, sensitive; diagonal screened bar, resistance to ampicillin , chloramphenicol, streptomycin, sulfonamides, and tetracyclines (ACSSuT; includes resistant-type ACSSuT and ACSSuT plus additional resistances to Tm, Cp L, or both); black bar, other resistance patterns.  
Dendrogram showing the relationships of pulsed-field gel electrophoresis profiles by the nearest neighbor technique. *Includes resistant (R)-type ACSSuT and ACSSuT plus additional resistances to Tm, Cp L, or both. A = ampicillin, C = chloramphenicol, Fu = furazolidone, K = kanamycin, Ne = neomycin, S = streptomycin, Su = sulfonamides, T = tetracyclines, Tm = trimethoprim, Cp L = ciprofloxacin.  
Article
Multiresistant Salmonella enterica serotype Typhimurium definitive phage type (DT) 12 and DT 120 are more closely related to DT 104 than to non-multiresistant strains of their respective phage types. Multiresistant DT 12 and DT 120 appear to have arisen due to changes in phage susceptibility of DT 104 rather than horizontal transfer of resistance genes.
 
Article
TO THE EDITOR: Human enterovirus (HEV) C (family Picornaviridae, genus Enterovirus) consists of 3 types of poliovirus (1, 2, and 3), 9 types of coxsackievirus A (CV-A1, 11, 13, 17, 19, 20, 21, 22, and 24), and 9 types of enterovirus (EV) (95, 96, 99, 102, 104, 105, 109, 113, and 116) (www.picornaviridae.com/enterovirus/hev-c/hev-c.htm). EV-104 was first identified in 2009 in Switzerland in 8 children who had pneumonia or acute otitis media (1). To our knowledge, there has been only 1 other report of EV-104, detected in Italy in 3 adults and 2 children who had upper respiratory tract infection (RTI) (2). We report the detection of a novel EV-104 strain in an adult with upper RTI in Japan.
 
Percentage composition of isoleucine and valine at position 221 in the neuraminidase of virus isolates and clinical specimens with reduced susceptibility to oseltamivir and peramivir, North Carolina, USA, 201011 influenza season*
Figure. Phylogenetic analysis of A) hemagglutinin and B) neuraminidase genes of Victoria lineage type B infl uenza viruses (n = 89). Red indicates the 2010-2011 Northern Hemisphere vaccine strain; blue indicates the cluster of infl uenza B viruses identifi ed in North Carolina carrying the I221V substitution in the neuraminidase; green indicates viruses collected from North Carolina with wild-type sequence at position 221 in the neuraminidase; black indicates representatives of globally circulating infl uenza B viruses. Month of collection is shown after virus strain designation. Evolutionary distances were computed by using the Tamura-Nei method (www. megasoftware.net/WebHelp/part_iv___evolutionary_ analysis/computing_evolutionary_distances/distance_ models/nucleotide_substitution_models/hc_tamura_ nei_distance.htm). Scale bars indicate number of base substitutions per site.  
Article
Oseltamivir is 1 of 2 antiviral medications available for the treatment of influenza B virus infections. We describe and characterize a cluster of influenza B viruses circulating in North Carolina with a mutation in the neuraminidase active site that may reduce susceptibility to oseltamivir and the investigational drug peramivir but not to zanamivir.
 
Figure. Geographic distribution of oseltamivir-resistant pandemic (H1N1) 2009 viruses in the United States, October 1, 2010-July 31, 2011. Numerators are number of oseltamivir-resistant viruses identifi ed by state public health laboratories; denominators are number of pandemic (H1N1) 2009-positive specimens submitted by each state for susceptibility testing. Gray shading indicates states that had >1 infection with oseltamivir-resistant virus. 
Article
During October 2010-July 2011, 1.0% of pandemic (H1N1) 2009 viruses in the United States were oseltamivir resistant, compared with 0.5% during the 2009-10 influenza season. Of resistant viruses from 2010-11 and 2009-10, 26% and 89%, respectively, were from persons exposed to oseltamivir before specimen collection. Findings suggest limited community transmission of oseltamivir-resistant virus.
 
Article
Serogroup W Neisseria meningitidis was the main cause of invasive meningococcal disease in Chile during 2012. The case-fatality rate for this disease was higher than in previous years. Genotyping of meningococci isolated from case-patients identified the hypervirulent lineage W:P1.5,2:ST-11, which contained allele 22 of the fHbp gene.
 
Article
TO THE EDITOR: Legionella pneumophila serogroups (SGs) 1-16 cause pneumonia in humans. Although SG 1 is the serogroup most commonly associated with disease (1), we report a case of community-acquired legionellosis caused by SG 11.
 
Article
In June 2009, during Singapore's pandemic influenza plan containment phase, pandemic (H1N1) 2009 was introduced into the country through imported cases. To understand how travel patterns affected the initial outbreak, we examined epidemiologic and travel data for the first 116 case-patients admitted to Tan Tock Seng Hospital, Singapore, with travel-associated infection. Sixty-one percent and 54% of patients, respectively, met US Centers for Disease Control and Prevention and World Health Organization temperature criteria for influenza-like illness. One fourth of the case-patients traveled after illness onset, and 15% became ill while traveling. Regions of exposure for imported infections changed rapidly; case-patients initially arrived from North America, followed by Australasia and Southeast Asia. Case-patients on longer flights were more likely to become ill before arrival; those with shorter flights tended to become ill after arrival. Thermal scanners detected fevers in 12% of the arriving case-patients, resulting in a shorter time to isolation.
 
Article
AmpC β-lactamase, altered porins, or both are usually responsible for cefoxitin resistance in Escherichia coli. We examined the relative importance of each. We studied 18 strains of clinical isolates with reduced cefoxitin susceptibility and 10 initially-susceptible strains passaged through cefoxitin-gradient plates. Of 18 wild-resistant strains, 9 had identical promoter mutations (including creation of a consensus 17-bp spacer) and related pulsed-field gel electrophoresis patterns; the other 9 strains were unrelated. Nine strains had attenuator mutations; two strains did not express OmpC or OmpF. After serial passage, 8 of 10 strains developed cefoxitin resistance, none developed promoter or attenuator mutations, 6 lost both the OmpC and OmpF porin proteins, and 1 showed decreased production of both. One strain had neither porin alteration or increased AmpC production. Porin mutants may occur more commonly and be less fit and less inclined to spread or cause disease than strains with increased β-lactamase expression.
 
Article
We describe 4 cases of Legionella pneumophila serogroup 13-associated pneumonia. These cases originate from a broad geographic range that includes Scotland, Australia, and New Zealand. L. pneumophila serogroup 13 pneumonia has a clinically diverse spectrum that ranges from relatively mild, community-acquired pneumonia to potentially fatal severe pneumonia with multisystem organ failure. All cases were confirmed by culture and direct fluorescent antibody staining or indirect immunofluorescent antibody tests. Proven or putative sources of L. pneumophila serogroup 13 infections in 2 patients included a contaminated whirlpool spa filter and river water. An environmental source was not found in the remaining 2 cases; environmental cultures yielded only other L. pneumophila serogroups or nonpneumophila Legionella species. We describe the clinical and laboratory features of L. pneumophila serogroup 13 infections. L. pneumophila serogroup 13 pneumonia is rarely reported, but it may be an underrecognized pathogenic serogroup of L. pneumophila.
 
Article
New guidance recommends annual influenza vaccination for all children 5-18 years of age in the United States. During 2007-2008, Hawaii offered inactivated and live attenuated influenza vaccine at school-located clinics for grades kindergarten through 8. Most (90%) public and private schools participated, and 622 clinics were conducted at 340 schools. Of 132,775 children 5-13 years of age, 60,760 (46%) were vaccinated. The proportion vaccinated peaked at 54% for those 6 years of age and declined for older cohorts. More than 90% of schoolchildren transited the clinic in <10 minutes. A total of 16,920 staff-hours were expended; estimated cost per dose administered was $27 and included vaccine purchase and administration, health staffing resources, printing costs, data management, and promotion. This program demonstrates the feasibility of conducting mass school-located influenza vaccination programs in public and private schools statewide, as might be indicated to respond to pandemic influenza.
 
Article
Nonpolio acute flaccid paralysis is increasing in India. To determine viral causes, we conducted cell culture and molecular analysis identification of nonpolio human enteroviruses associated with acute flaccid paralysis during March-August 2010 in northern India. The predominant nonpolio enterovirus found was echovirus 13, a serotype rarely isolated in India.
 
Temporal distribution of the Spanish echovirus 13 isolates during 2000. The isolates were grouped attending to their geographic origin as from the Iberian Peninsula and from the Canary Islands. The number of viruses included in the study (in parentheses) as well as the total isolates per month are shown. *Includes three sequences obtained directly from cerebrospinal fluid.
Histogram of the observed distances (Kimura two parameters method) within Canary Islands and Iberian Peninsula groups (dark gray) and between them (light gray). Analysis of variance (ANOVA) (one-way) test results: F=5238 (p=0.000). Distances within homologous groups: Canary Islands: mean 0.008 (standard deviation [SD] 0.004; n=351); Iberian Peninsula: mean 0.010 (SD0.006; n=666). Distances between heterologous groups (black): mean 0.033 (SD 0.005; n=999).
Phylogenetic tree of the 5' VP1 extreme showing the relationship between the Spanish isolates and others. The sequences included are the 14 Spanish echovirus 13 selected isolates as well as the German (n=12), Italian (n=1), Swedish (n=1), and Japanese (n=2) isolates. Phylogenetic tree reconstructed with the maximum-likelihood method, 50 Jumble. Gray sequences correspond to the 2001 isolates.  
Article
Echovirus 13 (EV13), considered rare, was reported worldwide in 2000, mostly related to aseptic meningitis outbreaks. In Spain, 135 EV13 isolates were identified. The genetic relationships between 64 representative strains from Spain and other reported isolates from the United States, Germany, Italy, Japan, and Sweden were described by analyzing the partial sequence of the major capsid protein (VP1) gene. The strains from Spain were clearly identified as EV13 (79.5% similarity with the EV13 reference strain) and were grouped phylogenetically into two different clusters (by origination on either the Iberian Peninsula or Canary Islands). Isolates from Germany from 2000 clustered with the Canary Islands group. The isolates from other countries obtained before 2000 were genetically distant. Changes in EV13 coding sequence involved several differences in the C-terminal extreme of the VP1 protein. Part of the neutralizing antigenic site III has been described in this genome region in poliovirus and swine vesicular disease virus.
 
Article
On the basis of a 14th-century account by the Genoese Gabriele de' Mussi, the Black Death is widely believed to have reached Europe from the Crimea as the result of a biological warfare attack. This is not only of great historical interest but also relevant to current efforts to evaluate the threat of military or terrorist use of biological weapons. Based on published translations of the de' Mussi manuscript, other 14th-century accounts of the Black Death, and secondary scholarly literature, I conclude that the claim that biological warfare was used at Caffa is plausible and provides the best explanation of the entry of plague into the city. This theory is consistent with the technology of the times and with contemporary notions of disease causation; however, the entry of plague into Europe from the Crimea likely occurred independent of this event.
 
Article
An outbreak of serogroup W-135 meningococcal disease occurred during the 2000 Hajj in Saudi Arabia. Disease was reported worldwide in Hajj pilgrims and their close contacts; however, most cases were identified in Saudi Arabia. Trends in Saudi meningococcal disease were evaluated and the epidemiology of Saudi cases from this outbreak described. Saudi national meningococcal disease incidence data for 1990 to 2000 were reviewed; cases from January 24 to June 5, 2000, were retrospectively reviewed. The 2000 Hajj outbreak consisted of distinct serogroup A and serogroup W-135 outbreaks. Of 253 identified cases in Saudi Arabia, 161 (64%) had serogroup identification; serogroups W-135 and A caused 93 (37%) and 60 (24%) cases with attack rates of 9 and 6 cases per 100,000 population, respectively. The 2000 Hajj outbreak was the first large serogroup W-135 meningococcal disease outbreak identified worldwide. Enhanced surveillance for serogroup W-135, especially in Africa, is essential to control this emerging epidemic disease.
 
Article
We document the absence of carriage of Neisseria meningitidis W-135 of the sequence type 11 in returning pilgrims after the Hajj 2002. This finding contrasts with the 15% carriage rate we previously reported in pilgrims returning from the Hajj 2001. The epidemiology of carriage may be changing or may have been controlled by vaccination and a policy of administering antibiotics to pilgrims from countries with a high incidence of meningococcal disease.
 
Estimates of the effect of interventions in reducing human risk for infection with avian influenza A(H7N9) virus in urban areas of Guangdong and Zhejiang provinces. Estimates are presented as effectiveness, calculated as 1 minus the ratio of incidence rates of infection after closure versus before closure, within 95% confidence intervals. Estimates are shown for each urban area, and a single summary measure is also shown assuming the effectiveness was the same across all areas. For Huaiji County and Nanhai District, live poultry markets (LPMs) epidemiologically linked to confirmed H7N9 cases were closed a few days before all the other local LPMs were closed. To account for differential start dates of LPM closure within these areas, we performed sensitivity analysis by setting the overall start date of LPM closure in a given area to be either the earliest or the last day on which local LPMs began to close. Results in the 2 scenarios were similar. 
Article
Closure of live poultry markets was implemented in areas affected by the influenza virus A(H7N9) outbreak in China during winter, 2013-14. Our analysis showed that closing live poultry markets in the most affected cities of Guangdong and Zhejiang provinces was highly effective in reducing the risk for H7N9 infection in humans.
 
Article
We identified a genotype G10P[14] rotavirus strain in 5 children and 1 adult with acute gastroenteritis from the Northern Territory, Australia. Full genome sequence analysis identified an artiodactyl-like (bovine, ovine, and camelid) G10-P[14]-I2-R2-C2-M2-A11-N2-T6-E2-H3 genome constellation. This finding suggests artiodactyl-to-human transmission and strengthens the need to continue rotavirus strain surveillance.
 
Article
We describe 3 culture-proven cases of adenovirus serotype 14 infection in New Brunswick, Canada, during the summer of 2011. Strains isolated from severely ill patients were closely related to strains of a genomic variant, adenovirus 14p1, circulating in the United States and Ireland. Physicians in Canada should be aware of this emerging adenovirus.
 
Circular map of plasmid pCT. Open reading frames are color coded as follows: brown, pseudogenes; orange, hypothetic proteins; light pink, insertion sequences; light blue, tra locus; green, pil locus; dark pink, antimicrobial drug resistance gene; yellow, putative sigma factor; red, replication-associated genes. Arrows show the direction of transcription. pCT, IncK plasmid. 
Artemis Comparison Tool (Sanger, Cambridge, UK) comparisons of IncK plasmid (pCT) with other plasmids. Complete DNA sequence plasmid comparisons. Bands of color indicate homology between sequences. Red lines show sequence in the same con fi rmation; blue lines indicate sequence inversion. The pCT sequence is represented as the top line of each comparison compared with pO26_vir (GenBank accession no. FJ38659) (A); R387 (B); R64 (accession no. AP005147) (C); and pEK204 (accession no. EU935740) (D) on each bottom line. 
Phylogenetic analysis of nikB in IncI complex plasmids from Escherichia coli . DNA sequences of nikB PCR amplicons and sequences obtained from public resources were aligned and analyzed by using MEGA 4.0 ( 29 ). A neighbor-joining tree was constructed by using complete deletion modeling and computed by using the maximum composite likelihood method ( 30 ). The phylogenetic tree was linearized assuming equal evolutionary rates in all lineages. Circles, nikB sequences from plasmids isolated from veterinary isolates from the United Kingdom; triangles, nikB sequences of plasmids from Escherichia coli isolated from humans; squares, nikB sequences of plasmids obtained from GenBank or the Sanger Institute; shaded shapes, plasmids identi fi ed as pCT-like by using PCR in this study; asterisks, plasmids encoding bla CTX-M-14 . pCT, 
Article
Antimicrobial drug resistance is a global challenge for the 21st century with the emergence of resistant bacterial strains worldwide. Transferable resistance to β-lactam antimicrobial drugs, mediated by production of extended-spectrum β-lactamases (ESBLs), is of particular concern. In 2004, an ESBL-carrying IncK plasmid (pCT) was isolated from cattle in the United Kingdom. The sequence was a 93,629-bp plasmid encoding a single antimicrobial drug resistance gene, blaCTX-M-14. From this information, PCRs identifying novel features of pCT were designed and applied to isolates from several countries, showing that the plasmid has disseminated worldwide in bacteria from humans and animals. Complete DNA sequences can be used as a platform to develop rapid epidemiologic tools to identify and trace the spread of plasmids in clinically relevant pathogens, thus facilitating a better understanding of their distribution and ability to transfer between bacteria of humans and animals.
 
Article
Despite a regional decline in influenza A(H1N1)pdm09 virus infections during 2013-14, cases at a Florida hospital were more severe than those during 2009-10. Examined strains had a hemagglutinin polymorphism associated with enhanced binding to lower respiratory tract receptors. Genetic changes in this virus must be monitored to predict the effect of future pandemic viruses.
 
Evolutionary relationships among influenza A (H1N1)pdm09 virus neuraminidase genes, United States, 2013–14. Phylogenetic tree was generated by using MEGA software v5.2 (http://www.megasoftware. net/) and the neighbor-joining method. Evolutionary distances were computed by using the maximum composite likelihood model. Analysis included 100 representative A(H1N1)pdm09 neuraminidase gene sequences. Scale bar indicates nucleotide substitutions per site. Solid circles indicate oseltamivirresistant H275Y markers. A/ California/07/2009 (current Northern Hemisphere vaccine strain) virus was used as a reference for ancestry (root) and numbering. F, Centers for Disease Control and Prevention reference antigen; Oct, October 2013; Nov, November 2013; Dec, December 2013; Jan, January 2014; Feb, February 2014; GLY, glycosylation.  
Article
We report characteristics of oseltamivir-resistant influenza A(H1N1)pdm09 viruses and patients infected with these viruses in the United States. During 2013–14, fifty-nine (1.2%) of 4,968 analyzed US influenza A(H1N1)pdm09 viruses had the H275Y oseltamivir resistance–conferring neuraminidase substitution. Our results emphasize the need for local surveillance for neuraminidase inhibitor susceptibility among circulating influenza viruses. © 2015, Centers for Disease Control and Prevention (CDC). All rights reserved.
 
Top-cited authors
Linda F Mccaig
  • Centers for Disease Control and Prevention
Vance Dietz
  • U.S. Department of Health and Human Services
Didier Raoult
  • Aix-Marseille Université
Duane Gubler
  • Duke-NUS Medical School
Roger I Glass