The mechanisms of severe pneumonia caused by co-infection of bacteria and influenza A virus (IAV) have not been fully elucidated. We examined apoptosis and inflammatory responses in a murine model for pneumococcal pneumonia during IAV infection. Inflammation, respiratory epithelium apoptosis, and inflammatory-cell infiltration increased in a time dependent manner in the lungs of mice co-infected with Streptococcus pneumoniae and IAV, in comparison with those infected with either S. pneumoniae or IAV. According to appearance of terminal deoxynucleotidyl transferase dUTP-mediated nick-end labeling positive cells, caspases-3 and -8 were activated 24 h after S. pneumoniae infection, and caspase-3 activation decreased after 48 h, whereas inflammatory cytokine levels continued to increase in co-infected mice. In contrast, in mice infected with either IAV or S. pneumoniae, apoptosis and activation of factors related to caspase-3 peaked at 48 h. Furthermore, Fas-associated death domain was significantly expressed in the lungs of co-infected mice 24 h after S. pneumoniae infection. These data suggest that early onset of apoptosis and its related factors play important roles in fulminant pneumonia resulting from bacterial pneumonia complicated by co-infection with influenza virus.
Trichophyton tonsurans has been isolated among judo practitioners, wrestlers, and sumo wrestlers during an epidemic of tinea corporis and tinea capitis in Japan. A previous study using restriction fragment length polymorphism (RFLP) analysis of the non-transcribed spacer (NTS) region of the ribosomal RNA gene revealed that different sources for the causative fungus in epidemics among judo practitioners and among wrestlers. Many different fungal strains have since been isolated from practitioners of these sports. The present study evaluated fungal characteristics of strains newly isolated between July 2006 and December 2010 using this molecular method. PCR-RFLP analysis using MvaI and AvaI was performed on 263 strains, composed of 186 isolates from judo practitioners, 32 from wrestlers, 30 from sumo wrestlers, 5 from other sports, 7 from family members or friends of the sports practitioner patients, and 3 from sporadic (non-epidemic) cases. Four molecular types, NTS I, II, III, and VII were detected. Of these, NTS I was the most predominant, occurring in 243 of 263 strains (92.4%). All of the 30 strains isolated from sumo wrestlers were classified as NTS I, suggesting that the epidemic among sumo wrestlers originated from an earlier epidemic among judo practitioners. Thirteen strains were classified as NTS II; all were related to wrestling and were isolated mainly from Chubu and Kansai areas in the central part of Honshu island. NTS III was detected in 6 strains, and one strain classified as NTS VII was isolated from a sporadic case of tinea capitis in a Peruvian immigrant. The minimum inhibitory concentrations (MICs) of terbinafine, itraconazole, fluconazole, and griseofulvin on 10 strains of NTS I and NTS II and 4 strains of NTS III were examined; there were no differences in MIC between these molecular types.
The central nervous system (CNS) tissue of mice infected with the CVS-11 strain of rabies virus (RABV) was subjected to gene expression analysis using microarray and canonical pathway analyses. Genes associated with innate immunity as well as inflammatory responses were significantly up-regulated, corroborating with the previous findings obtained using attenuated viruses that did not induce a fatal outcome in infected mice. Histopathological examination showed that neurons in the cerebellum had undergone apoptosis. Although the extent of Fas ligand up-regulation was not so prominent, perforin and granzyme genes were highly expressed in the CNS of mice infected with CVS-11. The presence of perforin and granzymes both in the Purkinje cells and CD3 T lymphocytes strongly suggested that apoptosis of the former cells was induced by the latter cells.
The identification of geographic trends of an influenza pandemic is important for analyzing its social epidemic factors. We performed spatiotemporal analyses focusing on the metropolitan areas in Japan by using the influenza-like illness (ILI) sentinel surveillance data for the pandemic (H1N1) 2009 and seasonal influenza. The epidemic curves and spread features expressed by the kriging method of geographic information system (GIS) and correlations between reported cases and demographic data were analyzed. The incidence of pandemic (H1N1) 2009 increased gradually at the beginning and showed more sporadic epidemic features compared to seasonal influenza. However, there were coincidental locations of patient clusters affected by the seasonal influenza, with a significant coefficient for the total sentinel reported cases (r = 0.71, P < 0.01). This suggested similar patterns of the epidemic over seasons. Patient clusters tended to be located in suburban areas, and there seemed to be stronger relationships between epidemics and higher ratio of larger families (with r = 0.26–0.35, P < 0.01, between ratio of families having more than 3 members and total reported cases in Tokyo and Nagoya areas). Whether populous areas had a greater probability of maintaining the epidemic patterns needs to be determined. Nonetheless, the patterns found in this study can be useful for further analyses for epidemic modeling and designing relevant controls.
Two effective vaccines for rotavirus infection will be available near future in Japan and data on the burden of rotavirus disease and the circulating rotavirus strains are urgently needed. To obtain these data, we set up active rotavirus hospitalization surveillance in three cities, Tsu, Matsusaka, and Ise in Mie Prefecture, Japan. From November 1, 2007 through October 31, 2009, we enrolled children <5 years of age who were hospitalized with a diagnosis of acute gastroenteritis (AGE) and collected information on age, sex, month of admission, city of residence, and symptoms at the time of hospitalization. Stool samples were also obtained for rotavirus testing and genotype investigation. Rotavirus infection accounted for approximately 40% to 50% of hospitalized AGE cases in each city, and approximately 63% of those hospitalized were 2 years of age or younger. Matsusaka had the highest incidence rate at 4.7 rotavirus hospitalizations per 1,000 children <5 years of age (95% confidence interval [CI]: 3.6–5.9), followed by Tsu City (4.4 per 1,000; 95% CI: 3.6–5.3), and Ise City (2.8 per 1,000; 95% CI: 2.0–4.0). The most dominant rotavirus genotype was G3P, which accounted for 73.1% of cases. Our findings confirm the substantial health burden of rotavirus AGE hospitalization among Japanese children <5 years of age.
Human rhinovirus (HRV) is a causative agent of acute respiratory tract infection (ARTI). In 2007, a novel HRV group, HRV-C, was discovered. This study, which assessed whether HRV-C is epidemic among patients with ARTI, was aimed at analyzing the seasonal prevalence of HRV-C in Osaka City, Japan. Gene amplification tests were performed to detect 10 respiratory viruses in 336 specimens collected during November 2008–October 2009. In total, 364 viruses were detected in 271 specimens. The most commonly detected virus was HRV (n = 84). For HRV-positive specimens, we conducted phylogenetic analyses using the VP4/VP2 gene region to identify the HRV species (HRV-C, 30; HRV-A, 54). Both the number and rate of HRV-C detection were highest in December. The highest numbers and the highest rate of HRV-A detection were obtained in April and June and in April, respectively. Statistical analysis showed that the most probable prevalent period of HRV-C was between September and March, and that of HRV-A was between March and November. These results suggest that HRV-C is mainly epidemic during autumn and early spring; this seasonal prevalence was different from that of HRV-A. Moreover, the HRV-C Osaka strains were scattered in many genetic clusters along with previously reported strains from different parts of the world. This result also emphasizes the worldwide circulation of HRV-C.
Human adenovirus type 8 (HAdV-8) is a common agent of severe epidemic keratoconjunctivitis (EKC). Twenty-six strains were isolated from sporadic cases of EKC in the southern part of Japan between 1998 and 1999 and were identified as HAdV-8 by the neutralization method using type-specific antiserum against HAdV-8. A comparative analysis of different HAdV-8 genome types was performed using various molecular methods. Restriction enzyme analyses of genomic DNA were performed with BamHI, HindIII, PstI, SacI, SalI, and SmaI and identified 25 isolates as HAdV-8E and 1 isolate as HAdV-8J, a novel genome type. The genetic relatedness between HAdV-8J and the other genome types was calculated by pairwise comigrating restriction fragments. The new genome type was most genetically related to HAdV-8E. In a phylogram of both the hexon and fiber, HAdV-8J formed a monophyletic cluster with other genome types of HAdV-8. Although HAdV-8J was identified from a sporadic case of EKC, this strain may cause future outbreaks and thus warrants further monitoring.
The mouse hepatitis virus (MHV) has a high mutation rate, leading to various neuropathologies after infection. The srr7 mutant was isolated from the MHV strain cl-2, which induces characteristic spongiform degeneration in the brain. To investigate outcomes of srr7 infection, we re-cloned srr7(H2) from the viral stock srr7(Mix). During this re-cloning, we obtained the mutant viruses, Mu-1, Mu-2, and Br-1 which was isolated from the mice brain infected with srr7(Mix). We examined mutant viruses for infectivity independent of the major MHV receptor (MHVR), because these mutants exhibited high virulence similar to cl-2, which is MHVR-independent. To confirm MHVR-independence in vitro, we used a combination of spinoculation and ultraviolet radiation to detect distinct plaque formation (SpinoPlaque(UV+)) afrer infection of BHK cells, which do not express MHVR. Using this technique, we found that the unique neuropathologies caused by infection with the mutant viruses result from infecting neurons, which do not express MHVR. Infection with the mutant viruses was 100% correlated with SpinoPlaque(UV+) formation. This is in contrast to infection with srr7, which does not from SpinoPlaque(UV+).
Syphilis is a sexually transmitted disease (STD) and is a major public health concern in India. The trend of syphilis infection was studied in attendees aged 15–49 years in an STD clinic in West Bengal from 2004 to 2008. Blood samples were collected from 250 consecutive patients per year (a total of 1,250 samples over 5 years); the patients attended the STD clinic for 12 weeks (October–December) each year, and the serostatus of syphilis was determined qualitatively with the Venereal Disease Research Laboratory (VDRL) test using serum samples. A quantitative VDRL test was then performed at a dilution of 1:8 using serum samples that yielded positive results in the qualitative VDRL test. Finally, serum samples that yielded positive results in the quantitative VDRL test were also subjected to the Treponema pallidum hemagglutination assay (TPHA). The serum samples that yielded positive results in both the tests were considered syphilis seropositive. All seropositive serum samples from the quantitative VDRL test were also found to be positive results in TPHA. The total seropositivity for syphilis in the STD patients was 8.2% (women, 8.9%; men, 7.7%). Review of the data from 5 consecutive years showed a statistically significant (χ2 = 9.968, df = 4, P < 0.05) decrease in syphilis positivity from 10.8% (2004) to 3.6% (2008). The results of the study also revealed that the highest seroprevalence was in the 20–24 age group (16.3%), and the lowest seroprevalence was in the 45–49 age group (3.3%). The study indicates the effectiveness of current interventions with a need to focus further on reducing the burden in the 20–24 age group.
Linezolid is a new antibiotic with activity against Mycobacterium tuberculosis in vitro and in vivo. This study aims to evaluate the efficacy and safety of linezolid in the treatment of extensively drug-resistant tuberculosis (XDR-TB). We used a linezolid-containing regimen in the treatment of 14 XDR-TB patients. Two years of individualized chemotherapy regimens were adopted on the basis of the patients’medication history and the results of drug susceptibility testing. The patients received 600 mg of linezolid twice a day for the first 1–2 months, followed by once a day thereafter. Eleven patients (78.6%) showed significant improvement in clinical symptoms. Chest computed tomography revealed that 10 patients (71.4%) showed cavity closure. Smear conversion and culture conversion were achieved in all 14 patients (100%) with an average of 64 and 63 days, respectively. The exact proportions of serious and minor adverse events determined by linezolid were 21.4% (3/14) and 64.3% (9/14), respectively. These data show that linezolid-containing chemotherapy for the treatment of XDR-TB may significantly improve clinical symptoms, promote lesion absorption and cavity closure, and accelerate sputum conversion. Further, adverse reactions can be tolerated and resolved with suitable intervention.
This retrospective study of the patterns and efforts of the extensive vaccination programs for canine rabies control (EVPCRC) compared the prevalence rate (PR) of rabies under two different vaccination programs for dogs in Korea between 1962 and 2007. A total of 753 cases of rabid dogs were reported between 1962 and 2007, and there were 350 human cases reported in the same period. There were 518 cases (PR, 4.11) of rabid dogs reported from 1962 to 1979, when the low-egg-passage Flury strain vaccine was used, and a total of 342 human cases were observed over the same period. However, there were 235 rabid dogs (PR, 0.83) identified from 1980 to 2007 when the Evelyn-Rokitnicki-Abelseth strain vaccine was used, and only 8 human cases of rabies were observed during the same period. The prevalence of rabies in dogs during the two periods was significantly different (P < 0.01). Moreover, the year with the largest outbreak, 1975, contained 91 cases, and the PR value was 6.3. In 1963, for humans, there were 103 cases, and the PR value was 0.4. However, in recent years, raccoon dogs have increased as a reservoir of rabies in the mountain areas linking North Korea with South Korea near the demilitarized zone, reflecting areas with poor EVPCRC.
The incidence of Brucella canis infection in humans is unknown in Turkey. In this study, we investigated the prevalence of B. canis infection in human sera obtained from six regions in Turkey and comparatively evaluated the results obtained by agglutination-based techniques using standardized antigens made from B. canis. The patients (n = 1,746) presented with clinical symptoms that were similar to those of brucellosis. All patients who tested negative in the Rose Bengal test for the smooth Brucella strains (abortus, melitensis, and suis) were screened for evidence of B. canis infection using the rapid slide agglutination test (RSAT), the microagglutination test (MAT), and the 2-mercaptoethanol RSAT test (2ME-RSAT). Of the samples tested, 157 (8.9%), 68 (3.8%), and 66 (3.7%) were positive for B. canis, as determined by RSAT, MAT, and 2ME-RSAT, respectively. The diagnostic sensitivity, specificity, positive predictive value, and negative predictive value of RSAT were 100%, 94.6%, 42%, and 100%, respectively, and of MAT were 100%, 99.9%, 97%, and 100%, respectively. We recommend the routine use of MAT and 2ME-RSAT to check the sera of all patients with symptoms of brucellosis who are negative for brucellosis using a smooth Brucella antigen.
Ten patients with intensive care unit (ICU)-acquired Chryseobacterium indologenes bacteremia between January 2004 and December 2008 were studied. The primary site of infection was unknown for 80% of the cases. The known primary sites of infection were empyema (10%) and catheter-related bacteremia (10%). Eight patients (80%) had polymicrobial bacteremia, spent more than 21 days in the ICU, and received more than 14 days of broad-spectrum antibiotic therapy prior to the onset of C. indologenes bacteremia. All isolates were 100% susceptible to minocycline and trimethoprim/sulfamethoxazole. Vancomycin, imipenem, piperacillin/tazobactam, ciprofloxacin, and levofloxacin exhibited 0%, 10%, 20%, 30%, and 30%, respectively, susceptibility against this pathogen. All isolates were 100% resistant to ceftazidime, cefepime, meropenem, piperacillin, and amikacin. The 14-day mortality rate was 40%. Our findings suggest that this pathogen should be included among the causes of ICU-acquired bacteremia, especially in patients with a prolonged stay in an ICU or who had received long-term broad-spectrum antibiotic therapy. Extended-spectrum penicillins, third- and fourth-generation cephalosporins, and quinolones had very little or no effect against this pathogen. Therefore, choosing an appropriate antibiotic therapy for this pathogen is very difficult.
We report a case of Q fever-related antiphospholipid syndrome in a patient presenting with acalculous cholecystitis and pneumonia. Serial laboratory tests indicated that the previous serological tests suggesting hepatitis C virus and Mycoplasma pneumoniae infections were false-positives. The patient's fever persisted despite treatment with doxycycline, but disappeared 1 day after initiation of steroid treatment. To avoid incorrect diagnosis and subsequent delays in appropriate treatment of Q fever patients, the possibility that Q fever can masquerade as other infections or as an autoimmune disease should be kept in mind.
We performed preepidemic and postepidemic serologic surveys to elucidate the rate of enterovirus 71 (EV71) infection in Lu'an City, Anhui Province, Central China. For the preepidemic study, a total of 472 healthy infants and children (age range, neonates to 15 years) were randomly selected before the 2008 outbreak of EV71 in the region. Blood samples were collected and tested for neutralizing antibodies (NAbs) against EV71 by performing a microneutralization assay. The results of preepidemic serological survey showed that 43.2% (204/472) of the tested samples yielded positive results for NAbs against EV71. The seropositivity rates were 29.6% (93/314) in children who were 0–7 years of age and 74.6% (59/79) in children who were 12–15 years of age. The overall geometric mean titer was 18.1, and the highest antibody titers were detected in children who were 5–7 years of age; this suggests that this group was frequently exposed to EV71 infection. For the postepidemic study, 83 serum samples were collected from healthy children ≤15 years of age in 2010. The seropositivity rate of EV71 NAbs increased in this young population after the 2008 outbreak, especially in 2- to 11-year-old children. This report shows that EV71 was spreading in Lu'an City before the 2008 outbreak, and children under 7 years of age were the main susceptible population.