Jundishapur Journal of Microbiology
Volume:7 Issue: 4, Apr 2014

Acute gastroenteritis is responsible observed in all age groups, especially infants and children. The etiology and clinical course of acute gastroenteritis may vary with age and etiological agents. In developing countries, the morbidity and mortality associated with infectious diarrhea is higher in children younger than five-years-of-age. The aim of this study was to determine the prevalence and seasonal distribution of the major agents of acute gastroenteritis in children who were admitted to a Turkish university hospital pediatric emergency unit during 2009.Patients and Seasonal distribution within a one year period and quantitative distribution were analyzed with demographic data and laboratory findings. A total of 644 subjects were enrolled in the study, with a mean age of 4.14 years. Pathogens were detected in 183 (28.4%) stool samples in children less than 16 years, admitted with acute gastroenteritis. Pathogens were detected in 184 (28.4%) stool samples. The age distributions of the cases were 0 - 24 months (n = 59), 2 - 5 years (n = 100), and > 5 years (n = 25). The detection rate of rotavirus, norovirus and adenovirus were; 12.7% (75/588), 9.8% (51/520) and 4.9% (28/575), respectively. Bacterial agents were detected in 36 cases. The main agent was norovirus in the 0 - 24 months group (n = 25, 42.4%), and rotavirus for ages 2 - 5 years (n = 43, 43%) and > 5 years. On the monthly distribution, cases of rotavirus were found to be more frequent in the first four months of the year. Viruses were the major pathogens in all age groups. Norovirus was the leading pathogen in the first two years. For the age groups 2 - 5 years and 6 - 16 years, rotavirus was the major pathogen..

The emerge of rapid and accurate detection of Meticillin-Resistant Staphylococcus aureus (MRSA) has been highlighted. The current study evaluated the prevalence of mec-A gene in biological specimens of various medical wards, in order to determine any possible relationship. Patients and Using traditional culture methods, 250 isolates were detected. The prevalence of mec-A mediated resistance was evaluated by PCR method. Among 98 isolates (39.2%) with resistant inhibition zones, 92 isolates carried mec-A gene and were considered as MRSA. Significantly higher rate of MRSA was observed in the specimens from emergency department and intensive care unit (P value < 0.001). Although, the prevalence of MRSA was higher in patients with history of previous hospital admission within the past three months (P = 0.006), but only one case with the same history was hospitalized in the emergency ward that was among the wards with the highest rate of MRSA. The study findings show that, although there is higher rate of MRSA infection in patients with history of hospitalization, but even in cases without any history of medical admission, more detailed questions emphasizing on receiving any recent health care should be asked in a referral hospital, in order to determine the true community-acquired MRSA.

Cryptosporidium is known to be one of the most important causes of diarrhea in children and immunocompromised patients. Genotype characterization of Cryptosporidium species in each region would help in the treatment of this disease, as well as to locate the source of infection and to prevent the disease. This current research was conducted in order to analyze the molecular characterization of isolated Cryptosporidium spp. in the Southwest of Iran. In this survey, 390 fecal samples were collected from immunocompromised individuals and children under five-years-of-age. Parasitic infection was evaluated using wet mount preparation, formalin ether, a modified acid fast staining method and microscopic examination. Finally, a PCR-RFLP assay was performed on the extracted DNA collected from fecal samples that were positive for Cryptosporidium by the acid fast method. Among the 390 fecal samples, 16 cases (4.1%) were infected with Cryptosporidium. Molecular and genotype characterization found the following protozoan species; 11 Cryptosporidium parvum (68.8%), 4 C. hominis (25%), and one case of C. meleagridis (6.2%). The present study emphasized the public health importance of Cryptosporidium spp. in the study area. In addition, it seems that zoonotic species are the most important causes of infection in the region. As far as we are aware this the first report of a C. meleagridis infection in Iran.

Staphylococci release a large number of enzymes. Some of these, such as coagulase, beta- lactamase, hemolysins and biofilms are considered indices of pathogenicity. The aim of the current study was based on the isolation and identification of Staphylococcus aureus and coagulase negative Staphylococci (CNS) strains from various skin lesions and examining their biofilms, beta- lactamase, hemolysins production and antibiotic resistance pattern. Sixty one infected wounds and 39 skin infections samples were collected and examined. After the culture and identification, examination for production of hemolysins, beta- lactamase, biofilm and susceptibility toward 9 antimicrobials was performed. Out of 75 isolated Staphylococci, sixty (80%) were biofilm producers. Two overall prevalence of 28.5% and 100% of ß-lactamase production were recorded for isolated S. aureus and CNS, respectively. Twenty out of 49 (40.8%), the same number of α- and β- hemolytic S. aureus, were isolated while six (12.24%) were ∂ -hemolysin producers. Twenty two of Twenty six (84.6%) isolates of CNS, were hemolysin producers that all were ∂ type. The S. aureus isolates from wound infections, show a high sensitivity pattern to all examined antibiotics, this sensitivity pattern for isolates from skin dermatitis is relatively low, though. High percentage of hemolysins, biofilm and beta lactamase production by isolated Staphylococci, suggests an important role of these virulence factors in the pathogenesis of isolated Staphylococci from dermatitis lesions. The S. aureus isolates from wound infections, show a high sensitivity pattern to all examined antibiotics. Only ciprofloxacin was found to be active against all isolates from dedermatitis lesions.

Yersinia species, especially Yersinia enterocolitica, are considered as the most prevalent milk-borne pathogens. Several serological and molecular techniques have been developed for rapid and safe diagnosis of yersiniosis. This study was carried out to assess the prevalence rate of Yersinia species, especially Y. enterocolitica, in milk and dairy products in Isfahan province, Iran. A total of 285 commercial and traditional dairy products as well as 267 pasteurized and raw milk samples were collected during one year. The samples were studied by culturing and the positive-culture samples were investigated using PCR techniques. The results of culture showed that 52 (9.42%) and 28 (5.07%) of the total 552 milk and dairy samples were positive for presences of Yersinia species and Y. enterocolitica, respectively. Totally, 24 of 28 Y. enterocolitica isolates by culture were positive in PCR test (4.59%). Raw cow milk and traditional cheese had the highest prevalence of Yersinia species and Y. enterocolitica, respectively. There were no positive results for pasteurized cow milk, raw camel milk, commercial ice cream, commercial cheese, yoghurt, Doogh, butter and curd. Yersinia species and Y. enterocolitica had the highest prevalence in autumn (15.15% and 10.6%, respectively). Significant differences regarding P < 0.05 were observed between the presences of Yersinia species and Y. enterocolitica in various samples and seasons. Sanitation and pasteurization are the best ways to increase the microbial quality and particularly decrease the load of Yersinia species. The ability of Yersinia species to growth in Doogh, yoghurt, curd and butter is very low.

Despite of the advances in infectious diseases prevention and food technology, food-borne diseases are considered major problems in developed and developing countries. Meat plays a key role in transferring zoonotic diseases to human. This study was conducted in south of Tehran, Iran, to investigate the prevalence rate of Salmonella spp. in packed and unpacked red meat and chicken. A total of 379 packed and unpacked samples including 189 red meat and 190 chicken samples were collected randomly. From each sample, 25 g was separated and treated with 225 mL of buffered peptone water, homogenized and incubated at 37°C for 24 hours. Samples were enriched using Rappaport-Vassiliadis broth and then streaked onto Hektoen enteric agar. Totally, 86 out of 190 chicken and 38 out of 189 red meat samples were contaminated with Salmonella spp. The most isolated serotypes were Salmonella thompson (67.7%), S. heaardt (6.5%), S. enteritidis (4.8%), and S. veyle (4%), respectively. In general, the rate of chicken contamination was higher than meat, as 43.3% of packed and 46% of unpacked chicken samples were contaminated. These results confirmed the pervious findings, stating that proper packaging of meat products can effectively decreases the rate of microbial contaminations.

Khuzestan and other parts of Iran were involved with Influenza A (H1N1) pandemic in 2009. The aim of this study was to describe the prevalence and mortality of H1N1 in Behbahan, a city in Khuzestan, Southwest of Iran.Patients and The study population consisted of cases of influenza, hospitalized or referred to the city health centers. Diagnosis of H1N1 virus infection was based on rapid antigen testing (RT-PCR) of nasopharyngeal swabs. Data extracted from epidemiological survey forms, including demographic and clinical characteristics, laboratory results, risk factors and underlying diseases, medications, and treatment outcomes of patients were analyzed using SPSS 16 software by using Pearson chi-square test. From a total of 318 patients, 180 (56.6%) were male and 138 (43.4%) female. Total number of patients with positive H1N1 tests was 167 (52.5%) with a male: female ratio of 1.2:1. Of total 318 admitted patients, 173 (96.1%) males and 135 (97.8%) females recovered and 10 people (7 (3.9%) males and 3 (2.3%) females) died, among which, three had positive test results for H1N1. The most prevalent signs and symptoms were: fever in 308 (96%) patients, cough in 278 (86.6%), lower respiratory symptoms in 208 (64.8%), gastrointestinal symptoms in 90 (28%), respiratory distress in 45 (13.7), and flu-like symptoms in 65 (20.2%) patients. Prevalence rate of H1N1 infection in the study region was higher compared to other part of Iran; but, close to the expected rate. The H1N1-associated mortality rate was lower than the reported rates in Iran and other parts of the world.

Many disease conditions including Staphylococcal infections are becoming increasingly difficult to treat in South Africa due to the surge of vancomycin-oxacillin resistant strains. How widespread this phenomenon is in commensal isolates in the Nkonkobe municipality in the Eastern Cape Province of South Africa is not known, and considering the high level of immunocompromised individuals in the province, this study couldn’t have come at a better time. The objective of this study is to evaluate the prevalence of vancomycin and oxacillin co-resistance in methicillin-resistant commensal staphylococci in Nkonkobe municipality, South Africa as part of our larger study on the surveillance of reservoirs of antibiotic resistance in South Africa. Staphylococcus species were isolated from domestic animals of Nkonkobe municipality, in the Eastern Cape Province of South Africa. The isolates were evaluated for antibiotic susceptibility against a panel of several relevant antibiotics. Specific primer sets were also used for the polymerase chain reaction assay to detect the presence of mecA gene as well as vanA and vanB genes in the genome of resistant Staphylococcus species. A total of 120 Staphylococcus isolates were screened, out of which, 32 (26%) were susceptible to both methicillin and vancomycin, while 12 (10%) had co-resistance to the antibiotics, which is still on the high side, both clinically and epidemiologically. Gentamicin (an aminoglycoside) had a relatively high potency against the isolates with 107 (89.17%) of the bacteria being susceptible to it, while 10 (8.33%) were resistant. On the other hand, erythromycin (a macrolide) was active against 72 (60%) of the isolates, while 5 (4.17%) and 74 (61.67%) of them yielded intermediate and resistant responses, respectively. Similarly, 51 (42.5%) of the isolates were susceptible to rifampicin, while 1 (0.83%) and 17 (14.17%) were intermediate and resistant, respectively. Ten percent of the isolates were positive for mecA gene among the vancomycin-oxacillin resistant strains, while van gene was not detected in any of the isolates. The data obtained would be useful in clinical control of resistant staphylococcal strains.

Cutaneous leishmaniasis (CL) is common and endemic in many areas of Iran, caused by species of a protozoan parasite belonging to the genus Leishmania. There is not any effective vaccine against leishmaniasis; so, therapy is important for prevention and separation of disease. Herbal extract for treatment of CL is cost-effective, applicable topically to lesions, and can avoid the development of drug resistance. The aim of this study was to evaluate the in vivo activity of an alcoholic extract of Hedera helix (a native Iranian plant) on the experimental ulcer of zoonotic CL in Balb/c mice. At least 5x l06 promastigotes of Leishmania major (MHOM/64/IR/ER75) were inoculated subcutaneously in the tail base of Balb/c mice. Fifty six infected mice were distributed in four groups, two groups (16 mice for 20% alcoholic extract of H. helix and 13 for 70% extract) were used as experimental groups, one (15 mice) as placebo control (Control A), and one (12 mice) as negative control. Treatment effects of two concentrations were determined by comparison of placebo and nontreated groups via measuring the size of skin lesions and the number of parasitologically positive and negative mice after the therapy period. This study showed that the main lesion size did not decrease significantly, or the small lesions did not completely disappear after treatment by H. helix alcoholic extract. Amastigotes counts (mean ± SD) of the skin lesions decreased in control A and 20% concentration groups, but in negative control and 70% concentration groups the number of parasites did not reduce. The present study did not support the in vivo antileishmanial effect of H. helix extract. We recommend further studies using major components of H. helix, especially hederasaponin (saponin K10), to investigate the antileishmanial effect of this plant on L. major.

Zinc is an essential micronutrient used in the form of zinc sulfate in fertilizers in the agriculture production system. Nitrogen-fixing microorganisms are also of considerable value in promoting soil fertility. This study aimed to investigate the degree of sensitivity to varying concentrations of zinc, in the form of ZnSO4, in different strains of Azotobacter chroococcum in a laboratory environment. To isolate A. chroococcum strains, soil samples were collected from wheat, corn and asparagus rhizospheres and cultured in media lacking nitrogen at 30˚C for 48 hours. Strains were identified based on morphological and biochemical characteristics. The presence of the nitrogenase enzyme system was confirmed by testing for the presence of the nifH gene using PCR analysis. The minimum inhibitory concentration (MIC) and optimal zinc concentration for the growth of each strain was determined. A total of 12 bacterial strains were isolated from six different soil samples. A. chroococcum strains were morphologically and biochemically characterized. The presence of the nifH gene was confirmed in all the strains. MIC and the optimal zinc concentration for bacterial growth were 50 ppm and 20 ppm, respectively. It was concluded that increasing the concentration of zinc in the agricultural soil is harmful to beneficial microorganisms and reduces the soil fertility. A 20-ppm zinc concentration in soil is suggested to be optimal.

For a long time, infertility has been one of the most sequels in medical sciences with microbial agents as one group of its causes. The possible etiological role of Chlamydia trachomatis in infertility was suggested years ago, but it has not yet been proved completely. To decrease the severe involvements of C. trachomatis infections, screening by efficient diagnostic methods are necessary.

In this study we attempted to determine the incidence of C. trachomatis in infertile women and compared this with healthy women.

This case-control study was performed on 150 infertile women with unknown causes and without physiological deficiency for infertility. The control group consisted of 200 fertile safe and impregnated women. Presence of C. trachomatis in the two groups was examined by direct and indirect immunofluorescence tests and PCR.

C. trachomatis was detected by direct immunofluorescence method in 23 (15.3%) infertile women compared and 7 (3.5%) healthy controls. Using indirect immunofluorescence tests, a positive test titer of 1:16 as well as the above results were detected in 34 (22.6%) of the infertile cases and 9 (4.5%) of the controls. C. trachomatis was detected by PCR method in 48 (32%) infertile women and 13 (8.7%) among the controls.

The results of our study suggest that there is a significant association between C. trachomatis infection and female infertility.

Observational studies, rather than randomized trials, revealed that statins might be associated with other benefits. The present study aimed at evaluating the preventive effects of lovastatin when used as a prophylactic agent for early and late infective complications after surgery.Patients and A total of 149 patients undergoing elective intracranial and spinal surgeries, were enrolled in a double- blind randomized clinical trial in the department of neurosurgery of a teaching hospital. An amount of 20 mg lovastatin and the same dose of placebo, one day before the operation and three days after the surgery, were used for cases and controls, respectively. The patients were evaluated for local and systemic infections during hospitalization and 10, 30, 60 and 90 days after discharge. A total of 149 patients, 78 men and 71 women with a mean age of 40.3 ± 16.5, were assigned to prophylactic protocols. 46 and 103 patients were in the case and control groups, respectively. Eight episodes of infection were detected, including six bacterial meningitis and two episodes of hospital- acquired pneumonia. All of the patients with documented postoperative infections were part of the placebo group, however, there were no significant statistical differences between the groups (P = 0.059). In spite of the differences between the two groups, the results did not significantly support the preventive effect of statins in postoperative infections.

Toxoplasma gondii is an obligatory intracellular protozoan parasite on which studies are pending regarding production of vaccine. To date, the production of human vaccine has not been successful where approximately one third of the world’s population is thought to be infected with T. gondii. The present study was designed to compare the electrophoretic patterns of T. gondii excreted/secreted antigens (ESAs) and determine their role in the stimulation of the humoral immune response. T. gondii ESAs were prepared from cell cultures (albino rat fibroblast) and cell-free mediums (RPMI-1640). Next, the SDS-PAGE technique was used for comparing molecular weights of the antigens. Forty C57BL/6 mice were divided randomly into four groups (n = 10). Immunization was performed subcutaneously at an interval of 2 weeks in two groups by injecting 100 µg of each of the above-mentioned antigens. Two groups, as negative control, also received fibroblast lysate proteins or adjuvant separately. All of the groups were then challenged with the T. gondii RH strain. Serum samples were collected from all mice and measured by immunoblotting technique for detection of immunogenic antigens. The electrophoretic mobility of the prepared antigens/proteins from cell culture, cell-free media, Fibroblast Lysate Proteins and Toxoplasma Lysate Antigens (TLA) showed 13, 12, 8 and 8 bands, respectively. The case groups, in challenge with T. gondii (RH strain), showed more survival prolongation than the control groups. Furthermore, the survival period was identical for both case groups with a tendency for slightly higher survival of mice receiving ESA from cell-free medium. Analysis of sera by immunoblotting also revealed one band of 65 KDa in sera from both case groups. We suggest that this band be extracted and its amino acids sequence determined to produce Synthetic Polypeptide for immunization studies.

Cutaneous Leishmaniasis (CL) is a parasitic disease in most parts of Iran, especially in the Isfahan province. The most common form of CL is a self-healing lesion but in rare situations, infection might develop to non-healing forms. Clinical symptoms and treatment process might be influenced by several agents such as host immune response and parasite strains. In this study, the isolates which caused healing and nonhealing forms of CL in Isfahan were characterized by internal transcribed spacer (ITS) polymerase chain reaction (PCR) technique. The aim of this study was to identify Leishmania species isolated from healing and non-healing CLs using PCR method.Patients and Thirty patients resident in Isfahan province, with healing or non-healing form of CL were entered into this study. After DNA extraction, the identification of Leishmania isolates was done by ITS1-PCR method. Leishmania major was found as the predominant species (100%) in both healing and non-healing forms of CL. It seems that there is no difference between Leishmania species in healing and non-healing forms of CL. In order to recognize the reason of long lasting lesions in non-healing patients, the study about parasite strains and immune factors at the molecular level mostly in nonhealing patient is recommended.

Hepatitis B infection, caused by hepatitis B Virus (HBV), is one of the major global public health problems. Hepatitis B Virus genotypes appear to show varying geographic distribution with possible pathogenic and therapeutic differences. Knowledge of HBV genotypes is very important for clinical treatment. Lamivudine is a nucleoside analogue that is clinically used to treat chronic hepatitis B infection. However, the main problem with the application of lamivudine is the development of viral resistance to the treatment with this anti viral drug. Besides, it has been suggested that lamivudine -resistant HBV may be genotype dependent. However, HBV genotype distribution and the biological relevance in this region are poorly understood. The current study aimed to determine hepatitis B genotypes and their correlation with lamivudine- resistant HBV frequency among patients with chronic hepatitis B from Shahrekord, Iran.Methods and Materials: Hepatitis B virus DNA was detected by conventional PCR in some of the serum samples obtained from HBsAg-positive Chronic Hepatitis B (CHB) patients who were referred to Health Centers of Shahrekord for routine monitoring of the disease. Subsequently, using real-time PCR, the DNA samples were used for genotyping and analysis of resistance to lamivudine. The DNA was detected in 23 out of 116 (19.82%) of the studied samples. Genotypes D and C were found in 17 out of 23 (73.9%), and in 6 out of 23 (26.1%) of the samples, respectively. To the authors’ best knowledge, the current study is the first report on isolation of Genotype C from Iran. Two out of 17 (11.76%), and 6 out of 6 (100%) of genotypes D and C were resistant to lamivudine, respectively. Resistance to this drug was significantly different between genotypes C and D (P <0.001). In addition to genotype D, other lamivudine resistant hepatitis B genotypes might be distributed in Iran.