Microsporidia are spore-forming obligate intracellular parasites. They are known to cause opportunistic infections in humans through zoonotic, waterborne and foodborne transmission routes. This article reviews the present knowledge regarding microsporidian Encephalitozoon cuniculi infections in animals living in the human environment in Japan and discusses the basic measures required for the effective disinfection of Encephalitozoon. The article also discusses seroepidemiologic data from healthy people in order to shed light on the mechanisms of protective immunity and to identify potential strategies for preventive medicine.

Diabetes mellitus (DM) is known as one of the factors that increases the risk of tuberculosis (TB). TB can also show atypical clinical presentation and localization in diabetics. The aim of the study was to evaluate the features of TB in diabetics in our region. Between 1997 and 2003, all cases of diabetic TB patients and an equal number of non-diabetics treated and followed at the Esrefpasa Tuberculosis Dispensary were analyzed retrospectively. A total of 78 (7.3%) TB cases in DM patients was encountered among 1,063 TB cases. Cavity formation and atypical localization were more often found in diabetics (P < 0.05). Duration of treatment was longer in diabetics (P < 0.05). The rate of drug resistance was higher in DM cases, but cure rates were similar between groups. A diagnosis of TB should be considered in diabetics with an abnormal chest radiograph, in the presence of absence of specific clinical symptoms, in endemic regions. Diabetic TB cases should be followed especially closely in terms of cure time and drug resistance.

Leptospirosis is a re-emerging infection, and often occurs in outbreaks. Early diagnosis is important for appropriate control measures and treatment. The sensitivity and specificity of the diagnostic test depends on the antigen, which is used for the detection of antibodies. In the present study, an effort was made to purify and characterize leptospiral antigens, and their performance in the laboratory was assessed. Leptospira biflexa semaranga, Patoc was subjected to processing by the heat extraction method, and the crude antigenic preparation was subjected to high-performance liquid chromatography for purification. The purified antigen fractions were subjected to enzyme-linked immunosorbant assay (ELISA) to determine their reactivity. Only the reactive fractions were tested for specificity by ELISA by allowing the fractions to react with positive sera of patients with non-leptospiral illness. H1, the purified antigen fraction of the heat-extracted preparation, was found to be the most reactive and specific of all fractions tested. The protein was found to have a molecular weight of 50 kDa. The performance of H1 in the laboratory was assessed by formulating an in-house ELISA using the H1 antigen. The results were compared with those of microscopic agglutination testing and commercial ELISA. The specificity and sensitivity of in-house ELISA using the H1 antigen were found to be 93.3 and 85.0%, respectively.

Of the 834 Salmonella spp. isolates collected from 2002 to 2004 in the New Territories East Cluster hospitals in Hong Kong, 21% were resistant to 3-14 antibiotics and 30% were resistant to nalidixic acid with reduced susceptibility to ciprofloxacin. A class 1 integron was present in 105 (13%) isolates, of which more than 50% were Salmonella Typhimurium. Class 2 or 3 integrons were not detected in any of the isolates. DNA sequencing showed that there were 16 different integrons, of which the most common, detected in 40% of isolates, was dfrA12-orfF-aadA2. Almost half of the isolates had lost the qacEΔ1-sulI 3′ conserved segment (3′CS). Four isolates had an orf513 gene downstream of the 3′CS. There was probably one predominant clone among each heterogeneous population of integron-harboring S. Typhimurium, S. Virchow, and S. Derby isolates in our community. This is the first thorough study of the prevalence and characteristics of integrons in Salmonella isolates in Hong Kong and the first to report a class 1 integron in S. Birkenhead, S. Landwasser, S. Litchfield, and S. Reading.

In this study, we investigated whether the occurrence of surgical site infection (SSI) could be decreased by a shorter duration of prophylactic antibiotic medications. Prophylactic antibiotic selection was a 1st or 2nd generation cephalosporin or sulbactam/ampicillin for 2 days for open surgery, laparoscopic surgery, transurethral lithotripsy (TUL), and transurethral resection of the prostate (TURP) as a rule, and 1 day for transurethral surgery other than TUL and for extracorporeal shock wave lithotripsy (ESWL). The kind of prophylactic antibiotics used was switched every 4 months in a year. Three patients had SSI out of the total 389 surgeries included in this study (0.77%). One had pyelonephritis after ESWL, one had urinary tract infection (UTI) after transurethral cutting and coagulation of bladder diverticulum, and one had UTI after TURP. There was no significant difference related to the kind of antibiotics used. However, the SSI occurrence was significantly lower than in the control group in which no definite intervention was performed with longer trends of prophylactic antibiotic usage (14/362, 3.87%) (P = 0.0111). In conclusion, we performed 389 urological surgeries with significantly decreased SSI rates using a shorter duration of prophylactic antibiotic medications than in the control group. The results indicate that this method might reduce the occurrence of SSI in urological surgeries.

In this study we assessed the existing communicable disease surveillance system in health centers of a province in northeastern Thailand. The first part of the study was an examination of medical records from 11 local health centers: 649 were examined for sensitivity, positive predictive value, and representativeness; and 433 were examined for timeliness and data quality. The second part of the study looked at 50 local officers from 11 local health centers, 1 district health office, 1 community hospital, and 8 sub-district administrative organizations. Quantitative data was collected through a review of medical records. Qualitative data was collected by focus groups and in-depth interviews. The reporting of suspected cases was 50.8%. Sensitivity was low for common diseases. Positive predictive value was lowest for fever of unknown origin (0%). Data quality for the date of onset and diagnosis was low. Case reporting was considered timely in only 45% of cases. Health officers perceived the surveillance system as not being up-to-date. They only collected data in a district without data analysis; the information provided by the system is not representative of the true epidemiological situation countrywide and cannot be used to help monitor disease patterns and trends. In conclusion, health officers should report diseases according to symptoms and analyze data continuously to identify urgent problem and elicit prompt responses.

We investigated a foodborne norovirus outbreak in a hospital and an attached long-term care facility (LTCF). An at-risk group of 698 people was identified, which included staff, hospital patients, LTCF residents, and adult daycare users who shared consumption of food prepared in a central kitchen. Three different diets were prepared in three separate sections: a standard diet, a special diet, and a diet for residents at the LTCF. During the first 3 days of the outbreak, 47 (16%) of 285 staff members and 55 (13%) of 413 patients became symptomatic. Eating the standard diet was significantly associated with a risk of illness for staff members (relative risk [RR], 18.13; 95% confidence interval [CI], 5.76-57.03) and patients (RR, 2.12; 95% CI, 1.05-4.31). Some stool samples were positive for norovirus GII/4. The standard diet may have been contaminated while being prepared in the central kitchen.

Quantitative real-time reverse transcription-polymerase chain reaction (q-RT-PCR) was used to diagnose echovirus infection and the results were compared to those obtained with the viral culture rate. Cerebrospinal fluid (CSF) from a total of 40 aseptic meningitis patients was used. Positive CSF samples, determined by viral culture (n = 29), contained significantly higher echovirus genome copy numbers (mean, 329 copies/µL) than did culture-negative CSF samples (n = 11) (mean, 34.2 copies/µL; P < 0.05). Echoviruses were identified as echovirus serotype 9 (E-9) (n = 21); E-30 (n = 16); and E-5, E-7, and E-18 (n = 1 each) by neutralization and/or conventional PCR-sequencing techniques. Viral culture-positive samples were collected at 1.41 ± 1.27 days after the onset of illness, and culture-negative samples were collected at 4.91 ± 3.34 days. Samples from which virus could be isolated were collected significantly earlier than were samples from which virus could not be isolated. These results strongly suggest the importance of early collection of CSF for echovirus isolation, and demonstrate the high sensitivity of q-RT-PCR for the detection of echoviruses in CSF.

This study investigated the prevalence of respiratory viruses, including respiratory syncytial virus (RSV), influenza virus types A and B (Flu A/B), parainfluenza virus (Para) 1-3, and adenovirus (Ad), in hospitalized children with acute lower respiratory tract infections (ALRIs). Immunofluorescence assays identified viral etiology in 412 patients younger than 16 years old. The overall viral isolation rate was 63.1% (260/412). The RSV was detected in 25.0%, Flu A/B in 19.4%, Para 1-3 in 14.6%, and Ad in 4.1% of the total sample. Multiple viruses were detected in 6.6% of the study population. Most viral infections occurred in the first 5 years of life, and the incidence of viral infection peaked during early spring and winter. Infection with Ad often resulted in the development of severe pneumonia in older children, and during the summer. The sequences of the isolated Ad hexons belonged to species B, and were closely related to the Gomen strain isolated in the United States in the 1950s. The study results will help determine the etiologic agents of ALRI in children and establish prevention and treatment programs.

We report the case of a 62-year-old woman with Acinetobacter baumannii bacteremia. She was admitted to our hospital with ventricular tachycardia and was subsequently diagnosed with idiopathic ventricular tachycardia, with no structural heart disease. However, 12 days after admission, she suddenly developed a high-grade fever with chills and diarrhea. Her blood cultures revealed A. baumannii, and the patient was treated with meropenem and amikacin sulfate. Yet, the patient's symptoms and clinical signs became worse. We then began to administer a large quantity of intravenous ampicillin-sulbactam, and the patient improved dramatically. Although rare, bloodstream infection caused by A. baumannii tends to be severe. Therefore, when A. baumannii is found in a patient's bloodstream, clinicians should start appropriate treatment immediately and should recall ampicillin-sulbactam as a sensible option for treatment.

We investigated the trial of the influenza HA vaccination for healthcare workers in 2 consecutive years at Nihon University Itabashi Hospital. The vaccination rate increased significantly (P < 0.01) from the first season to the second season. The number of missed working days in the vaccinated group was significantly lower (P < 0.01) than that in the unvaccinated group in a mild-pandemic year. Furthermore, the relative risk of infection was 0.53 and the effectiveness rate of the vaccine was 46.8%. Absenteeism and influenza infection rates were also significantly lower in the vaccinated group. This study may support the possibility of influenza vaccination for healthcare workers to prevent the outbreak of influenza in hospitals.

We surveyed the rate of chlamydial and gonococcal infections among human immunodeficiency virus (HIV)-seropositive patients in Thailand as well as the current status of antimicrobial resistance of Neisseria gonorrhoeae and determined the prevalence of penicillinase-producing N. gonorrhoeae (PPNG) in Thailand. A total of 1,158 endocervical swabs from 824 HIV-seropositive patients were collected to detect both organisms by Gen-Probe. The prevalences of chlamydial and gonococcal infection were 9.7 and 1.3%, respectively. Susceptibility of 122 gonococcal isolates to 6 drugs was determined by the disk diffusion method. None of the isolates was susceptible to penicillin or tetracycline. With respect to fluoroquinolones, more than 90% of the isolates were resistant to ciprofloxacin and ofloxacin. No gonococcal isolate with resistance to cefotaxime and ceftriaxone was detected. Among the 122 isolates, 83.6% or 102 isolates were PPNG, and most (79.5%) of these 122 isolates were further identified as PPNG plus tetracycline-resistant N. gonorrhoeae, with only 4.1% being PPNG alone. All of the 102 isolates identified as PPNG contained the bla_TEM gene. We then performed a preliminary molecular study and identified, for the first time in Thailand, a PPNG isolate producing beta-lactamase and containing the bla_TEM gene which was identical to the beta-lactamase TEM protein of Salmonella enterica identified as TEM-135.

A survey of human enterovirus (HEV) infections from 2004 to 2008 was conducted in Yokohama City, Japan. A total of 260 clinical samples in 247 patients were shown to be positive for enterovirus. Among them, 25 serotypes were identified, including 3 serotypes of poliovirus (19 samples). The prevalence rates of hand-foot-and-mouth disease (HFMD), herpangina, and respiratory illness associated with nonpolio HEV infections were also analyzed. Seven serotypes were highly associated with HFMD or herpangina. These 7 virus serotypes were prevalent during summer and autumn with a peak in July, and were prevalent in children under 6 years old with a peak from 1 to 2 years old. HEV-related diseases were not limited to HFMD and herpangina but also included respiratory illnesses, such as the common cold. The results of this study suggested the importance of periodic surveys to monitor severe diseases caused by HEVs.

Leptospirosis has emerged as an important infectious disease in Sri Lanka and little information is available on circulating leptospiral species and serogroups in this country. Therefore, we studied circulating leptospiral species and serogroups in patients with acute febrile illness using polymerase chain reaction and the microscopic agglutination test, respectively. Anti-leptospiral antibodies were detected in 26 of 107 serum samples studied (24.3%). The predominant reacting serogroups were Sejroe (9/26, 34.6%) and Icterohaemorrhagiae (5/26, 19.2%). Leptospiral DNA was detected in 3 of the 107 serum samples. The deduced leptospiral species were Leptospira interrogans and L. kirschneri (2 and 1 samples, respectively). These results confirm the existence of a wide array of leptospiral species and serogroups in Sri Lanka and would help to thoroughly elucidate the epidemiology of leptospirosis in this country.

Two novel multiplex polymerase chain reaction (mPCR) assays were originally developed for detecting nine targeted virulence-associated genes of five categorized diarrheagenic Escherichia coli (DEC). The mPCR assay 1 included five primer sets (stx1, eaeA, invE, STp gene, and astA), and assay 2 included four primer sets (stx2, aggR, STh gene, and LT gene). The two mPCRs showed 100% specificity in identifying the reference strains without nonspecific bands, and 51 DEC and 38 astA gene-positive E. coli strains from 683 E. coli-like isolates. Our mPCR methods showed high sensitivity and specificity for detecting nine virulence genes of DEC strains. We proved that these methods will contribute to reducing the cost for the reagents of mPCR reported elsewhere and could, therefore, contribute to the diagnosis of DEC in clinical laboratories.