Carbapenemases increasingly have been reported in Enterobacteriaceae in the past 10 years. Klebsiella pneumoniae carbapenemases have been reported in the United States and then worldwide, with a marked endemicity at least in the United States and Greece. Metallo-enzymes (Verona integron–encoded metallo-β-lactamase, IMP) also have been reported worldwide, with a higher prevalence in southern Europe and Asia. Carbapenemases of the oxacillinase-48 type have been identified mostly in Mediterranean and European countries and in India. Recent identification of New Delhi metallo-β-lactamase-1 producers, originally in the United Kingdom, India, and Pakistan and now worldwide, is worrisome. Detection of infected patients and carriers with carbapenemase producers is necessary for prevention of their spread. Identification of the carbapenemase genes relies mostly on molecular techniques, whereas detection of carriers is possible by using screening culture media. This strategy may help prevent development of nosocomial outbreaks caused by carbapenemase producers, particularly K. pneumoniae.

Naturally acquired human infections with Plasmodium knowlesi are endemic to Southeast Asia. To determine the prevalence of P. knowlesi malaria in malaria-endemic areas of Thailand, we analyzed genetic characteristics of P. knowlesi circulating among naturally infected macaques and humans. This study in 2008–2009 and retrospective analysis of malaria species in human blood samples obtained in 1996 from 1 of these areas showed that P. knowlesi accounted for 0.67% and 0.48% of human malaria cases, respectively, indicating that this simian parasite is not a newly emergent human pathogen in Thailand. Sequence analysis of the complete merozoite surface protein 1 gene of P. knowlesi from 10 human and 5 macaque blood samples showed considerable genetic diversity among isolates. The sequence from 1 patient was identical with that from a pig-tailed macaque living in the same locality, suggesting cross-transmission of P. knowlesi from naturally infected macaques to humans.

Oseltamivir has been widely used for pandemic (H1N1) 2009 virus infection, and by April 30, 2010, a total of 285 resistant cases were reported worldwide, including 45 in the United Kingdom. To determine risk factors for emergence of oseltamivir resistance and severe infection, a case–control study was conducted in the United Kingdom. Study participants were hospitalized in England or Scotland during January 4, 2009–April 30, 2010. Controls had confirmed oseltamivir-sensitive pandemic (H1N1) 2009 virus infections, and case-patients had confirmed oseltamivir-resistant infections. Of 28 case-patients with available information, 21 (75%) were immunocompromised; 31 of 33 case-patients (94%) received antiviral drugs before a sample was obtained. After adjusting for confounders, case-patients remained significantly more likely than controls to be immunocompromised and at higher risk for showing development of respiratory complications. Selective drug pressure likely explains the development of oseltamivir resistance, especially among immunocompromised patients. Monitoring of antiviral resistance is strongly recommended in this group.

Borrelia miyamotoi is distantly related to B. burgdorferi and transmitted by the same hard-body tick species. We report 46 cases of B. miyamotoi infection in humans and compare the frequency and clinical manifestations of this infection with those caused by B. garinii and B. burgdorferi infection. All 46 patients lived in Russia and had influenza-like illness with fever as high as 39.5°C; relapsing febrile illness occurred in 5 (11%) and erythema migrans in 4 (9%). In Russia, the rate of B. miyamotoi infection in Ixodes persulcatus ticks was 1%–16%, similar to rates in I. ricinus ticks in western Europe and I. scapularis ticks in the United States. B. miyamotoi infection may cause relapsing fever and Lyme disease–like symptoms throughout the Holarctic region of the world because of the widespread prevalence of this pathogen in its ixodid tick vectors.

We estimated the attack rate of pandemic (H1N1) 2009 and assessed risk factors for infection among close contacts quarantined in Beijing, People’s Republic of China. The first 613 confirmed cases detected between May 16 and September 15, 2009, were investigated; 7,099 close contacts were located and quarantined. The attack rate of confirmed infection in close contacts was 2.4% overall, ranging from 0.9% among aircraft passengers to >5% among household members. Risk factors for infection among close contacts were younger age, being a household member of an index case-patient, exposure during the index case-patient’s symptomatic phase, and longer exposure. Among close contacts with positive test results at the start of quarantine, 17.2% had subclinical infection. Having contact with a household member and younger age were the major risk factors for acquiring pandemic (H1N1) 2009 influenza virus infection. One person in 6 with confirmed pandemic (H1N1) 2009 was asymptomatic.

We conducted a case–control study to investigate risk factors for multidrug-resistant tuberculosis (MDR TB) in the People’s Republic of China. Genotyping analysis was used to estimate the percentage of cases from recent transmission among 100 MDR TB case-patients hospitalized during April 2007–July 2009. Molecular subtyping of isolates showed that 41% of MDR TB strains clustered. Beijing genotype was found in 94% of the MDR TB isolates and 79% of the pan-susceptible isolates. In multivariate analysis, MDR TB was independently associated with Beijing genotype, retreatment for TB, symptoms lasting >3 months before first evaluation at the hospital, lack of health insurance, and being a farmer (vs. being a student). MDR TB was associated with Beijing genotype and lower socioeconomic status. A large percentage of MDR TB cases seemed to result from recent transmission. Early detection, effective treatment, and infection control measures for MDR TB are needed to reduce transmission.

An increase in the incidence of empyema worldwide could be related to invasive pneumococcal disease caused by emergent nonvaccine replacement serotypes. To determine bacterial pathogens and pneumococcal serotypes that cause empyema in children in Australia, we conducted a 2-year study of 174 children with empyema. Blood and pleural fluid samples were cultured, and pleural fluid was tested by PCR. Thirty-two (21.0%) of 152 blood and 53 (33.1%) of 160 pleural fluid cultures were positive for bacteria; Streptococcus pneumoniae was the most common organism identified. PCR identified S. pneumoniae in 74 (51.7%) and other bacteria in 19 (13.1%) of 145 pleural fluid specimens. Of 53 samples in which S. pneumoniae serotypes were identified, 2 (3.8%) had vaccine-related and 51 (96.2%) had nonvaccine serotypes; 19A (n = 20; 36.4%), 3 (n = 18; 32.7%), and 1 (n = 8; 14.5%) were the most common. High proportions of nonvaccine serotypes suggest the need to broaden vaccine coverage.

The prevalence and spread of azole resistance in clinical Aspergillus fumigatus isolates in the Netherlands are currently unknown. Therefore, we performed a prospective nationwide multicenter surveillance study to determine the effects of resistance on patient management strategies and public health. From June 2007 through January 2009, all clinical Aspergillus spp. isolates were screened for itraconazole resistance. In total, 2,062 isolates from 1,385 patients were screened; the prevalence of itraconazole resistance in A. fumigatus in our patient cohort was 5.3% (range 0.8%–9.5%). Patients with a hematologic or oncologic disease were more likely to harbor an azole-resistant isolate than were other patient groups (p<0.05). Most patients (64.0%) from whom a resistant isolate was identified were azole naive, and the case-fatality rate of patients with azole-resistant invasive aspergillosis was 88.0%. Our study found that multiazole resistance in A. fumigatus is widespread in the Netherlands and is associated with a high death rate for patients with invasive aspergillosis.

Recent reports describe increasing incidence of non-Aspergillus mold infections in hematopoietic cell transplant (HCT) and solid organ transplant (SOT) recipients. To investigate the epidemiology of infections with Mucorales, Fusarium spp., and Scedosporium spp. molds, we analyzed data from the Transplant-Associated Infection Surveillance Network, 23 transplant centers that conducted prospective surveillance for invasive fungal infections during 2001–2006. We identified 169 infections (105 Mucorales, 37 Fusarium spp., and 27 Scedosporium spp.) in 169 patients; 124 (73.4%) were in HCT recipients, and 45 (26.6%) were in SOT recipients. The crude 90-day mortality rate was 56.6%. The 12-month mucormycosis cumulative incidence was 0.29% for HCT and 0.07% for SOT. Mucormycosis incidence among HCT recipients varied widely, from 0.08% to 0.69%, with higher incidence in cohorts receiving transplants during 2003 and 2004. Non-Aspergillus mold infections continue to be associated with high mortality rates. The incidence of mucormycosis in HCT recipients increased substantially during the surveillance period.

We report a case of Rickettsia honei infection in a human in Nepal. The patient had severe illness and many clinical features typical of Flinders Island spotted fever. Diagnosis was confirmed by indirect immunofluorescent assay with serum and molecular biological techniques. Flinders Island spotted fever may be an endemic rickettsiosis in Nepal.

During 2010, an outbreak of West Nile virus infection occurred in Greece. A total of 197 patients with neuroinvasive disease were reported, of whom 33 (17%) died. Advanced age and a history of heart disease were independently associated with death, emphasizing the need for prevention of this infection in persons with these risk factors.

In China in 2010, a disease outbreak in egg-laying ducks was associated with a flavivirus. The virus was isolated and partially sequenced. The isolate exhibited 87%–91% identity with strains of Tembusu virus, a mosquito-borne flavivirus of the Ntaya virus group. These findings demonstrate emergence of Tembusu virus in ducks.

We used viral metagenomics to identify a novel parvovirus in tissues of a gray fox (Urocyon cinereoargenteus). Nearly full genome characterization and phylogenetic analyses showed this parvovirus (provisionally named gray fox amdovirus) to be distantly related to Aleutian mink disease virus, representing the second viral species in the Amdovirus genus.

Bacterial distribution and antimicrobial drug resistance were monitored in patients with bacterial bloodstream infections in rural hospitals in Ghana. In 2001–2002 and in 2009, Salmonella enterica serovar Typhi was the most prevalent pathogen. Although most S. enterica serovar Typhi isolates were chloramphenicol resistant, all isolates tested were susceptible to ciprofloxacin.

During 2008–2009 in Israel, equine encephalosis virus (EEV) caused febrile outbreaks in horses. Phylogenetic analysis of segment 10 of the virus strains showed that they form a new cluster; analysis of segment 2 showed ≈92% sequence identity to EEV-3, the reference isolate. Thus, the source of this emerging EEV remains uncertain.

To determine prevalence of Cyclospora cayetanensis infection in Henan, China, we conducted a study of 11,554 hospital patients. Prevalence was 0.70% (95% confidence interval 0.70% ± 0.15%), with all age groups infected. Most cases were found in the summer. Minor sequence polymorphisms were observed in the 18S rRNA gene of 35 isolates characterized.

Yellow fever vaccine–associated viscerotropic disease is a rare sequela of live-attenuated virus vaccine. Elderly persons and persons who have had thymectomies have increased susceptibility. A review of published and other data suggested a higher than expected number of deaths from yellow fever vaccine–associated viscerotropic disease among women 19–34 years of age without known immunodeficiency.

During September–October 2010, an unprecedented outbreak of Rift Valley fever was reported in the northern Sahelian region of Mauritania after exceptionally heavy rainfall. Camels probably played a central role in the local amplification of the virus. We describe the main clinical signs (hemorrhagic fever, icterus, and nervous symptoms) observed during the outbreak.

To assess herd immunity to swine influenza viruses, we determined antibodies in 28 paired serum samples from participants in a prospective serologic cohort study in Hong Kong who had seroconverted to pandemic (H1N1) 2009 virus. Results indicated that infection with pandemic (H1N1) 2009 broadens cross-reactive immunity to other recent subtype H1 swine viruses.

Two cases of Plasmodium knowlesi infection in humans were identified in Cambodia by 3 molecular detection assays and sequencing. This finding confirms the widespread distribution of P. knowlesi malaria in humans in Southeast Asia. Further wide-scale studies are required to assess the public health relevance of this zoonotic malaria parasite.

We report an outbreak of equine piroplasmosis in southern Texas, USA, in 2009. Infection prevalence reached 100% in some areas (292 infected horses). Amblyomma cajennense was the predominant tick and experimentally transmitted Theileria equi to an uninfected horse. We suggest that transmission by this tick species played a role in this outbreak.

In the context of a large outbreak of Shiga toxin–producing Escherichia coli O104:H4 in Germany, we quantified the timeliness of the German surveillance system for hemolytic uremic syndrome and Shiga toxin–producing E. coli notifiable diseases during 2003–2011. Although reporting occurred faster than required by law, potential for improvement exists at all levels of the information chain.

To investigate global epidemiology of Shigella sonnei, we performed multilocus variable number tandem repeat analysis of 1,672 isolates obtained since 1943 from 50 countries on 5 continents and the Pacific region. Three major clonal groups were identified; 2 were globally spread. Type 18 and its derivatives have circulated worldwide in recent decades.

In Africa, incidence and prevalence of drug-resistant tuberculosis have been assumed to be low. However, investigation after a 2005 outbreak of extensively drug-resistant tuberculosis in KwaZulu-Natal Province, South Africa, found that the incidence rate for multidrug-resistant tuberculosis in KwaZulu-Natal was among the highest globally and would be higher if case-finding efforts were intensified.

We tested 259 methicillin-resistant Staphylococcus aureus isolates and 2 USA300 ATCC type strains for susceptibility to bacitracin and neomycin contained in over-the-counter antibacterial ointments. Resistance to both bacitracin and neomycin was found only in USA300. The use of over-the counter antimicrobial drugs may select for the USA300 clone.

To investigate arenavirus in Zambia, we characterized virus from the kidneys of 5 arenavirus RNA–positive rodents (Mastomys natalensis) among 263 captured. Full-genome sequences of the viruses suggested that they were new strains similar to Lassa virus–related arenaviruses. Analyzing samples from additional rodents and other species can elucidate epizootiologic aspects of arenaviruses.

We report an unusual case of pandemic (H1N1) 2009–related encephalitis in an immunocompetent woman. Although rare cases of pandemic (H1N1) 2009 associated with encephalitis have been reported previously, in this patient, direct viral invasion of the central nervous system was shown by simultaneous detection of viral RNA and pleocytosis.

During August–November 2009, to investigate disease transmission within households in Taiwan, we recruited 87 pandemic (H1N1) 2009 patients and their household members. Overall, pandemic (H1N1) 2009 virus was transmitted to 60 (27%) of 223 household contacts. Transmission was 4× higher to children than to adults (61% vs. 15%; p<0.001).

To determine whether an association exists between group B streptococcus carriage and HIV infection, we recruited 1,857 pregnant women (21.7% HIV positive) from Queen Elizabeth Central Hospital, Blantyre, Malawi. Overall, group B streptococcus carriage was 21.2% and did not differ by HIV status. However, carriage was increased among HIV-positive women with higher CD4 counts.

During 2001–2007, to determine incidence of all hantavirus infections, including those without pulmonary syndrome, in western Panama, we conducted 11 communitywide surveys. Among 1,129 persons, antibody prevalence was 16.5%–60.4%. Repeat surveys of 476 found that patients who seroconverted outnumbered patients with hantavirus pulmonary syndrome by 14 to 1.

In response to an outbreak of Crimean-Congo hemorrhagic fever in western Afghanistan, we measured immunoglobulin G seroprevalence among household members and their animals. Seroprevalence was 11.2% and 75.0% in humans (n = 330) and livestock (n = 132), respectively. Persons with frequent exposure to cattle had an elevated risk of being immunoglobulin G positive.

To determine whether women in KwaZulu-Natal, South Africa, with drug-resistant tuberculosis (TB) were more likely than men to have extensively drug-resistant TB, we reviewed 4,514 adults admitted during 2003–2008 for drug-resistant TB. Female sex independently predicted extensively drug-resistant TB, even after we controlled for HIV infection. This association needs further study.

Clostridium difficile, the most commonly recognized diarrheagenic pathogen among hospitalized persons, can cause outpatient diarrhea. Of 1,091 outpatients with diarrhea, we found 43 (3.9%) who were positive for C. difficile toxin. Only 7 had no recognized risk factors, and 3 had neither risk factors nor co-infection with another enteric pathogen.

Travelers’ diarrhea is a major public health problem. From patients in whom diarrhea developed after travel to India, 5 enteroaggregative Escherichia coli strains carrying β-lactamase CTX-M-15 were identified; 3 belonged to clonal complex sequence type 38. This β-lactamase contributes to the multidrug resistance of enteroaggregative E. coli, thereby limiting therapeutic alternatives.

In studying the epidemiology of parvovirus 4 (PARV4) in Taiwan, we detected DNA in plasma of 3 mothers and their newborns with hydrops. In 1 additional case, only the mother had PARV4 DNA. Our findings demonstrate that PARV4 can be transmitted through the placenta.