Determining the coverage and efficacy of the COVID-19 vaccination program at the community level in children aged 12 to 17 in Tehran.

Background: The vaccination is one of the acceptable and recomended solution to prevent and control of COVID-19. The aim of this study was to determine the efficacy of sinopharm vaccination in children aged 12-17 in Tehran. Methods: The case population study was performed from October 2021 to March 2022 among 1,500 children with positive PCR test reffered in Mofid Children's Hospital in Tehran. 64 children aged 12-17 years were included. The data were collected by the hospital information system (HIS), vaccination information registration systems and questionnaire with their families. The coverage and efficacy of vaccination determined with equels commented by WHO. Results: Out of 64 children, 52 children were 12 to 15 years old (13.35±1.08), 12 children were 16 to 17 years old (16.55±0.52). 48.4% had received two doses of vaccine. The highest rate of positive PCR was observed in February 2022. Sinopharm vaccine coverage in this age group was 93.6% for the first dose and 81.1% for the second dose. Based on this information, 48.4% children in this study have received two complete doses of the COVID-19 vaccine. The efficacy of the vaccine was estimated as 94.4% (95% CI 90.2 to 97.7). Conclusion: It seems the coverage of Sinopharm vaccination in the age group of 12-17 years in Tehran is favorable and has high efficacy in this age group. In order to obtain more accurate and comprehensive estimation, it is recommended to take a sample on a wider level of the community.

Evidence-Based Prediction of COVID-19 Severity in Hospitalized Children.

Objective: In this study, by using clinical and paraclinical characteristics, we have aimed to predict the severity of the disease in hospitalized COVID-19 children. Method: This cross-sectional study was conducted on medical records about epidemiologic data, underlying diseases, symptoms, and laboratory tests from March to October, 2020, on 238 hospitalized confirmed COVID-19 paediatric cases in several children's hospitals of Tehran, Ahwaz, Isfahan, and Bandar Abbas. Results: From 238 patients, 140 (59%) were male and most of them were in the age group of 1 to 5 years (34.6%). Among all hospitalized patients, 38% had an underlying disease and in total, 5% of cases were expired. Conclusion: Determining patient severity is essential for appropriate clinical decision making; our results showed that in hospitalized pediatric patients, by using several variables such as SGOT, CRP, ALC, LDH, WBC, O2sat, and ferritin, we can use clinical and paraclinical characteristics for predicting the severity of COVID-19.

Iranian Pediatric COVID-19 Epidemiology and Clinical Characteristics.

BACKGROUND: Despite the worldwide spread of Severe Acute Respiratory Syndrome Corona Virus 2 (SARS-CoV-2), information about the epidemiological and clinical patterns of this infection is still largely unknown in children. In addition, the prevalence of this disease is still very high in some parts of the world, including Iran. Thus, this study aims to evaluate the epidemiological features, laboratory and imaging findings, and the type of treatments in children with novel coronavirus 2019 (COVID-19). METHOD: This study is conducted from March 2020-March 2021 by using the medical records of hospitalized confirmed COVID-19 children younger than 18 years in five cities of Iran: Tehran, Ahwaz, Isfahan, Bandar-Abbas, and Khorramabad. In addition to demographic and epidemiological data, we also studied clinical signs and treatments. RESULTS: In total 278 confirmed COVID-19 children, the average age was 5.3 years, and 59.4%were boys. A total of 37.8% had an underlying disease, in which the most common was a malignancy. The most common symptoms were fever and cough. In this group of pediatrics, some abnormal laboratory findings have been seen. GGO (Ground-Glass Opacity) had been diagnosed in 58.6% of children. 3.6% needed oxygen therapy with ventilators, and 83.09% had received antibiotic treatments with the majority of ceftriaxone. Also, 10% had got steroids. In this study, the mortality rate was 4.3%. CONCLUSION: In this study, most of the children who died had an underlying disease, so timely care and action is important in them. Most children admitted to our study received antibiotics and were prescribed antivirals and steroids for a smaller number. Also, a small number of children received oxygen therapy, most of whom were in the age group of 1 to 5 years.

Effect of Haemophilus influenzae Type b Vaccination on Nasopharyngeal Carriage Rate in Children, Tehran, 2019.

BACKGROUND: Haemophilus influenzae (H. influenzae) strains, which commonly reside as commensals within the human pharynx and can remain as an asymptomatic carrier, but become invasive leading to pneumonia, septic arthritis, or meningitis. The Pentavac (pentavalent vaccine, manufactured by India, SII (DTwP-HepB-Hib)) was introduced to the Iranian National Immunization Plan in November 2014. The aim of this study is to investigate H. influenzae type b (Hib) carrier rate among children under 6 years old in Tehran. METHODS: This cross-sectional study was performed on 902 children including vaccinated/unvaccinated in the age of 6 months to 6 years, in Tehran. Sampling was performed from July 2019 to September 2019. Nasopharyngeal samples were taken from children by sterile swab. The PCR method was used to extract DNA. Then, all H. influenzae isolates were initially confirmed by molecular tests. BexA was used to distinguish typeable H. influenzae strains from nontypeable Haemophilus influenzae (NTHi). RESULTS: A total of 902 children were enrolled in the study: 452 were female (51%). H. influenzae carriage rate was 267 (29%), of that 150 samples (16.6%) were typeable. The nasopharyngeal Hib carrier rate in the children was 2.6% (24/902). 262 cases did not receive Hib vaccine. Analysis in nonnursery's children aged 4 to 6 (unvaccinated) years showed that the lower educational level of father, mother, and family number correlated with increased odds of colonization of children with Hib. CONCLUSION: Our findings showed a significant decrease (60%) in the overall Hib nasopharyngeal carriage in healthy children under six years after 5 years after the start of Hib vaccination.

Diagnosis of latent tuberculosis infection among pediatric household contacts of Iranian tuberculosis cases using tuberculin skin test, IFN- γ release assay and IFN-γ-induced protein-10.

BACKGROUND: Although the World Health Organization has recommended the diagnosis and prophylactic treatment of latent tuberculous infection (LTBI) in child household contacts of tuberculosis (TB) cases, the national programs in high-burden TB regions rarely implement adequate screening of this high-risk group, mainly because of resource limitations. We aimed to evaluate the prevalence of LTBI among pediatric household contacts of TB cases in two high-burden provinces in Iran. METHODS: We conducted a cohort study in children who had been in household contact with a TB index. All subjects were assessed for active TB disease. For LTBI diagnosis, tuberculin skin test (TST) and QuantiFERON®-TB Gold Plus (QFT-Plus) were performed at the time of the index TB case diagnosis, as well as, 3, 12, and 18 months, if the first results were negative. In addition, interferon-γ-induced protein-10(IP-10) concentrations were measured for all participants. RESULTS: A total of 230 children were enrolled, who had contact with an index TB case. Three contacts were diagnosed with active TB. According to the TST/QFT-Plus results, 104 (45.2%) children were identified with LTBI during our study. Significantly increased IP-10 levels were found in LTBI patients compared to healthy contacts. Accordingly, more than 50% of LTBI contacts and about 10% of healthy contacts were considered as IP-10-positive. CONCLUSION: This study alarmingly illustrates a high prevalence of LTBI among Iranian children exposed to TB cases. We, therefore, emphasize that the children living in close contact with an infectious TB case should be screened effectively and receive prophylactic therapy.

A Systematic Review and Meta-Analysis of Serotype Distribution of Streptococcus Pneumoniae in Iran: Practical Evidence to Optimizing Local Vaccination Protocols.

BACKGROUND: Little is known regarding the burden of predominant circulating serotypes of Streptococcus pneumoniae in Iran. Therefore, this study aimed to investigate the serotype distribution of pneumococcal diseases in Iran by using a comprehensive systematic review of available articles. ; Methods: A systematic literature search was carried out to identify papers published by Iranian authors in the Web of Science, PubMed, Scopus, Embase and Google Scholar electronic databases from January 2000 to December 2018. Then, eight publications that met our inclusion criteria were selected for data extraction and analysis by Comprehensive Meta-Analysis software. ; Results: In total, three studies reported the distribution of S. pneumoniae serotypes among patients, two studies among healthy individuals, and three studies among both groups. Of those studies, serotype 19A/F (17.9%; 95% CI: 13.6-23.0) was the most circulating serotype followed by 23A/F (12.3%; 95% CI: 7.7-19.2), 6A/B (11.0%; 95% CI: 8.0-14.9), and 14 (8.8%; 95% CI: 5.8-13.2). In contrast, the lowest circulating serotype was 60 (0.02%; 95% CI: 0.0-1.2), 29 (0.07%; 95% CI: 0.01-5.0), and 36 (0.09%; 95% CI: 0.04-2.1). Meta-regression results showed that prevalence of serotype 23A/F significantly increased each year about 0.2% (95% CI: 0.1-0.3, P <0.001, tau2 <0.001). ; Conclusion: In the present study, it was found that over the last decade, the most prevalent serotypes in Iran were 19, 23, 6, and 14, respectively. These findings provide practical evidence to select effective pneumococcal vaccine candidates for the prevention of invasive diseases in Iranian patients and also to compare our situation with others.

Evaluation of Blood and Liver Cytotoxicity and Apoptosis-necrosis Induced by Nanochelating Based Silver Nanoparticles in Mouse Model.

This study aimed to evaluate the in-vitro and in-vivo biological activities of newly synthesized nanochelating based silver nanoparticles (AgNPs) in mouse model. Nanochelating technology was used to design and synthesize the AgNPs. The animals studies were including the lethal dose (LD50) determination by the intraperitoneal administration in mice, and determination of liver enzymes levels and hematological parameters. Flow cytometry analysis was used to quantitatively determine apoptosis and necrotic cells in-vitro. The NPs A and NPs B have LD50 = 250 mg/kg and LD50 = 350 mg/kg, respectively and classified as non-toxic. In general, minor alterations were observed in levels of liver enzymes as indicative of liver damage. For blood parameters several factors associated with significant changes in AgNPs treated animals. Regarding animals weight, combination therapy showed more effective to maintain animals weight losses after infection. Flow cytometry results showed that AgNPs induced cell apoptosis-necrosis depends on AgNP size, concentration and exposure time. Cells damage due to AgNPs (A) with lower size (20-25 nm) were relatively more than cells exposed to AgNPs (B) (30-35 nm). The findings support the potent antibacterial activities of nanochelating based AgNPs. Also, the present study showed that nanochelating based AgNPs induce a moderate level of apoptosis/necrosis in mice, and affected several clinical parameters like blood parameters, liver enzymes, and body weight with no definite signs of toxicity.

Serosurvey and molecular detection of the main zoonotic parasites carried by commensal Rattus norvegicus population in Tehran, Iran.

BACKGROUND: Rattus norvegicus are reservoirs for transmission of various zoonotic parasites, and they have become a threat to public health worldwide. Given the large number and the significant presence of R. norvegicus throughout the city of Tehran, this study aims to assess the frequency of zoonotic parasites carried by commensal rodents wandering in Tehran, Iran. The study considered the north, south, west, east, and center regions of Tehran for the purposes of this study. The serological tests were applied in order to detect effective antibodies against Trichomonas vaginalis (T. vaginalis), Babesia spp., and Cryptosporidium spp. using a commercial qualitative rat ELISA kit. The frequency of Toxoplasma gondii (T. gondii) was surveyed by using the conventional PCR method. Furthermore, nested PCR was employed to detect the presence of Giardia spp. and Leishmania spp. in commensal R. norvegicus dispersed in Tehran. RESULTS: Approximately, 76% of the 100 R. norvegicus tested were infected with at least one zoonotic parasite, indicating the significant frequency of parasites within the study areas. Seroreactivity against T. vaginalis, Babesia spp., and Cryptosporidium spp. was detected in 5%, 0%, and 1% of the R. norvegicus tested, respectively. T. gondii DNA was detected in 32 out of 100 (32%) R. norvegicus. In addition, Leishmania spp. and Giardia spp. DNA were found in 18 out of 100 (18%) and 76 out of 100 (76%) R. norvegicus investigated, respectively. T. vaginalis with 15% and T. gondii with 70% had the highest frequency of parasites among the R. norvegicus collected from the western and northeastern regions of Tehran, respectively. Moreover, Giardia spp. with 95% and Leishmania spp. with 30% had the highest frequency in the east and center districts, respectively. CONCLUSION: The findings showed a wide geographical dissemination of Giardia spp., Toxoplasma gondii, and Leishmania spp. in R. norvegicus within five districts of Tehran. In contrast, other parasites such as Cryptosporidium spp. infection were rarely detected in Rattus populations. No evidence for the circulation of Babesia spp. was found in this study.

Epidemiology of Panton-Valentine Leukocidin harbouring Staphylococcus aureus in cutaneous infections from Iran: a systematic review and meta-analysis.

Panton-Valentine Leukocidin (PVL) producing Staphylococcus aureus has been associated with severity of skin infections and pathology that suggest a major role in pathogenicity. The present study aimed to determine the overall prevalence of PVL harbouring S. aureus isolates from cutaneous infections in Iran. A systematic search was performed by using Medline electronic databases (PubMed) from the papers published by Iranian authors to the end of March 2017. Ten publications which met our inclusion criteria were then selected for data extraction and analysis by Comprehensive Meta-Analysis Software. The pooled prevalence of PVL in cutaneous infections was estimated at 27.9% (95% CI: 17.9-40.6). The range of PVL positivity among S. aureus isolates obtained from cutaneous infections was from 7.4% to 55.6%. In summary, despite the emergence of multiple-drug resistant strains, it seems that the overall prevalence of PVL carrying S. aureus in Iran remains steady regardless of methicillin resistance. However, further research is required to elucidate the interplay between the risk of invasive disease and PVL, especially in Iran.

IgE response to two new allergen proteins of Solanum melongena L. (eggplant).

A number of allergens from eggplant (Solanum melongena L.) have been previously identified. In this study, we could detect IgE reactivity of two allergic subjects' sera towards two protein bands of molecular mass of about 35 and 15 kDa. As IgE were reactive to both raw and cooked eggplant extracts, a heat-stable nature of these novel allergens is apparent.

Emergence of SCCmec Type I Obtained From Clinical Samples in Shiraz Teaching Hospitals, South-West of Iran.

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) continues to be a major cause of nosocomial infections. Methicillin resistance in S. aureus is caused by the acquisition of the mecA gene, located on a mobile genetic element called the staphylococcal cassette chromosome (SCC). OBJECTIVES: The aim of this study was to evaluate the presence of the predominant SCCmec type present among clinical isolates. MATERIALS AND METHODS: This cross-sectional study was performed on a total of 146 MRSA isolates obtained from clinical specimens between 2012 and 2013 from two major hospitals in Shiraz, Southwest of Iran. Antibiotic susceptibility profiles were determined by the disc diffusion method according to the guidelines of The Clinical and Laboratory Standards Institute. Bacterial DNA was extracted using the small-scale phenol-chloroform extraction method and was employed as polymerase chain reaction (PCR) templates for the assigned current SCCmec types. RESULTS: The assigned SCCmec types by PCR revealed the SCCmec type I as the predominant type with 86 (58.9%) samples, followed by the SCCmec type II with 29 (19.9%), type III with 16 (11.0%), and type IV with 12 (8.2%) samples, respectively. The SCCmec type I MRSA isolates were significantly recovered from blood (80%) and sputum (67.2%). The results of antibacterial susceptibility tests for the MRSA isolates showed that all of those carrying the SCCmec type I and II had significantly greater resistance rates to Gentamicin and Rifampin than the isolates containing the SCCmec type III. Also, a significant difference was detected for susceptibility to Co-trimoxazole between the SCCmec type I and II MRSA isolates and the SCCmec type III, which was more resistant. CONCLUSIONS: The frequency of the isolates containing type I in the current study can indicate an emergence of this SCCmec type in the studied medical centers.

Composition, Cytotoxic and Antimicrobial Activities of Satureja intermedia C.A.Mey Essential Oil.

In this study, the essential oil (EO) constituents from the aerial parts of Satureja intermedia C.A.Mey were detected by GC and GC/MS. The antimicrobial activity of EO on oral pathogens and its cytotoxicity to human cancer cells were determined by the microbroth dilution method and the crystal violet staining method, respectively. Thirty-nine compounds were identified and the main EO constituents were γ-terpinene (37.1%), thymol (30.2%), p-cymene (16.2%), limonene (3.9%), α-terpinene (3.3%), myrcene (2.5%), germacrene B (1.4%), elemicine (1.1%) and carvacrol (0.5%). The S. intermedia EO showed a concentration-dependent decrease in viability of Hep-G2 (hepatocellular carcinoma) and MCF-7 (breast adenocarcinoma) human cancer cell lines (p < 0.05). Antimicrobial screening of S. intermedia EO demonstrated slight antibacterial and antifungal activities against Streptococcus mutants, S. salivarius, Enterococcus faecalis, Staphylococcus aureus, Candida albicans and C. glabrata. Further preclinical studies are needed to assess the efficacy and safety of S. intermedia EO as a new promising anticancer agent.

Frequency of adenoviruses, rotaviruses and noroviruses among diarrhea samples collected from infants of zabol, southeastern iran.

BACKGROUND: Viruses are one of the major reasons of gastrointestinal disease worldwide, and commonly infect children less than five years of age in developing countries. OBJECTIVES: The current study aimed to determine the frequency of adenoviruses, rotaviruses and noroviruses among diarrhea samples collected from infants of Zabol, south-east of Iran. This study is the first investigation of adenoviruses, rotaviruses and noroviruses among diarrhea samples in Zabol. PATIENTS AND METHODS: In this study, eighty-two diarrhea stool samples were collected from infants aged < 1 to 12 months admitted to the hospital, internal laboratory and central laboratory of Zabol, Iran. All samples were subjected to the rapid immunochromatography assay. RESULTS: The results showed that the frequency of rotaviruses, adenoviruses and noroviruses among infants with diarrhea were 70.20%, 20.30% and 9.50%, respectively. There were 50 subjects aged one to five months and 2 subjects aged nine to twelve months. The results of geographical distribution showed that the number of infants living in rural and urban areas with these viruses were 50 and 32, respectively. Rotaviruses were most common in rural and urban infants with 42 and 10 cases, respectively. Regarding the feeding patterns of infants with diarrhea, mixed feeding and breast feeding were found in 51 and 31 cases, respectively. CONCLUSIONS: In conclusion, the results of our study showed that the major viral pathogens that caused infantile diarrhea in Zabol city were rotaviruses followed by adenoviruses and noroviruses. The results of our study can useful for prosperous control of infantile diarrhea.

Phytochemical compositions and biological activities of essential oil from Xanthium strumarium L.

The chemical composition of the essential oil (EO) from fresh cocklebur (Xanthium strumarium L.) leaves was investigated by GC-MS. The antimicrobial activity of the EO was tested against Gram-positive and Gram-negative bacteria and fungi. Scolicidal activity was assayed against Echinococcus granulosus protoscolices. In total, 34 compounds were identified, accounting for 98.96% of the EO. The main compounds in the EO were cis-ß-guaiene (34.2%), limonene (20.3%), borneol (11.6%), bornyl acetate (4.5%), ß-cubebene (3.8%), sabinene (3.6%), phytol (3.1%), ß-selinene (2.8%), camphene (2.2%), α-cubebene (2.4%), ß-caryophyllene (1.9%), α-pinene (1.8%) and xanthinin (1.04%). The antibacterial and antifungal screening of the EO showed that all assayed concentrations significantly inhibited the growth of Staphylococcus aureus, Bacillus subtilis, Klebsiella pneumoniae, Pseudomonas aeruginosa, Candida albicans and Aspergillus niger (MIC = 0.5 ± 0.1, 1.3 ± 0.0, 4.8 ± 0.0, 20.5 ± 0.3, 55.2 ± 0.0 and 34.3 ± 0.0 µg/mL, respectively). The scolicidal assay indicated that the EO exhibited a significant activity against E. granulosus protoscolices. To the best of our knowledge, this is the first report on the scolicidal activity of X. strumarium. Because of the emergence of antimicrobial drug resistance, the study of new effective natural chemotherapeutic agents, such as the X. strumarium EO, possibly with low side effects, represents a very promising approach in biomedical research.

Antibacterial, antioxidant, antifungal and anti-inflammatory activities of crude extract from Nitraria schoberi fruits.

This study is the first comprehensive investigation of the antibacterial, antioxidant, antifungal and anti-inflammatory activities of a crude extract from Nitraria schoberi L. (Zygophyllaceae) fruits. The extract was tested against four Gram-negative (Pseudomonas aeruginosa, Enterobacter aerogenes, Klebsiella pneumoniae and Acinetobacter lwoffii) and one Gram-positive (Staphylococcus aureus) bacteria using the agar disc diffusion and microdilution methods. P. aeruginosa was inhibited the most (widest inhibition zone) while K. pneumonia showed the largest MIC value. The antioxidant activity of fruits (0.02 mg/mL vs. 0.04, 0.06 and 1.00 mg/mL for α-tocopherol, butylated hydroxyanisole and ascorbic acid, respectively) was determined by the paired diene method. The antifungal activity of N. schoberi fruits was tested against different fungi, including Aspergillus niger and Candida albicans, with 300 µg/mL of fruit extract being the most effective concentration. The percentage of anti-inflammatory activity assayed for N. schoberi fruit extract at 100, 200 and 500 µg/mL was 36.12, 59.89 and 88.33 %, respectively. N. schoberi fruits possess potent antibacterial, antioxidant, antifungal and anti-inflammatory properties, and may be used as an antibacterial and antifungal to treat diseases and/or as a protective agent against disorders associated with oxidative stress and inflammation.

Chemical composition and biological activity of Pulicaria vulgaris essential oil from Iran.

The present study investigated the chemical composition of the essential oil (EO) from aerial parts (flowering stage) of Pulicaria vulgaris Gaertn. by GC-MS. Also, the antimicrobial activity of the EO against Gram-positive bacteria (Bacillus cereus and Staphylococcus aureus), Gram-negative bacteria (Escherichia coli and Pseudomonas aeruginosa) and fungi (Aspergillus niger and Candida albicans) was tested. In total, 23 compounds were recognized, accounting for 98.08% of the EO. The main compounds in the EO were thymol (50.22%), p-menth-6-en-2-one (carvotanacetone, 20.2%), thymol isobutyrate (16.88%), menthan-2-one (4.31%), 1-methyl-1,2-propanedione (4.13%), 2,5-dimethoxy-p-cymene (4.01%), myrtenol (1.22%), linalool (1.1%), and ß-myrcene (1.9%). Results of antibacterial test of P. vulgaris essential oil showed that all assayed concentrations significantly inhibited the growth of B. cereus, S. aureus, E. coli, and P. aeruginosa at P < 0.05. MIC for B. cereus, S. aureus, E. coli, P. aeruginosa was 17.5, 25.2, 19.4 and 33.2 µg/mL respectively; antifungal screening of the essential oil of P. vulgaris showed that the oil significantly inhibited the growth of A. niger and C. albicans (MIC = 15.5 and 9.9 µg/mL, respectively). Results of cytotoxicity assay showed that the essential oil exhibited a significant cytotoxic activity against both cell lines. In case of MCF-7 and Hep-G2 cell lines, IC50 of the essential oil were 5.36 and 7.16 µg/ml, respectively. The potent antimicrobial and cytotoxic activities of the EO may be attributed to its high contents of thymol, carvotanacetone and thymol isobutyrate. Antimicrobial and antitumor chemotherapies are showing diminishing effectiveness because of emergence of drug-resistance. Hence, using efficient natural chemotherapeutic agents such as Pulicaria vulgaris essential oil with fewer side effects is an encouraging approach to fight cancer and infectious diseases in medicine, agriculture, food science and related fields.

Analysis of Virulence Genes Among Methicillin Resistant Staphylococcus aureus (MRSA) Strains.

BACKGROUND: Staphylococcus aureus is amongst major human pathogens both in hospitals and the community. This bacterium is an opportunistic pathogen responsible for a large number of self-limiting and even life-threatening diseases in humans. Methicillin resistant S. aureus (MRSA) strains are common causes of emerging nosocomial infections and are considered as a major problem for public health. OBJECTIVES: WE AIMED TO STUDY THE PROFILE OF SOME VIRULENCE GENES INCLUDING: sea, seb, sed, tst, eta, etb, LuKS/F-PV, hla and hld in methicillin-resistant S. aureus by the PCR technique. MATERIALS AND METHODS: A total of 345 isolates of S. aureus were collected from clinical specimens of patients referred to teaching hospitals of Shiraz; identification was done by biochemical (catalase, coagulase and DNase) and molecular tests. One hundred and forty six isolates of methicillin-resistant S. aureus (MRSA) were obtained and the presence of some toxin genes in these isolates was investigated by the polymerase chain reaction (PCR) technique. RESULTS: The results showed that among the 345 isolates of S. aureus, 148 were confirmed as MRSA by screening with the cefoxitin disc diffusion (30 µg) method. Also among the 148 MRSA isolates, 146 isolates were confirmed as methicillin-resistant by molecular methods. The results showed that the frequency of methicillin-resistant and methicillin-sensitive S. aureus isolates during 2012 to 2013 in Namazi and Faghihi hospitals were 146 (42.3%) and 199 (57.7%), respectively. Besides, among the 146 confirmed MRSA isolates, 36.98% (54 isolates) and 63.02% (92 isolates) were related to female and male, respectively. The largest number of cases belonged to sputum samples (58 out of 146). The frequency of the eta, etb, sed, LuKS/F-PV, seb, tst, sea, hld and hla genes were 0.68%, 2.05%, 2.05%, 5.47%, 10.95%, 11.64%, 27.39%, 84.24% and 93.15%, respectively. In addition, amongst all examined genes, hla (93.15%) and eta (0.68%) genes had the highest and lowest frequencies, respectively. The greatest coexistence of genes was observed for the hla + hld gene combination (48.83%). The results of our study indicate that 98.63% of the isolates were positive for at least one of the virulence genes. CONCLUSIONS: The relative higher frequency of some virulence genes in this study may reflect the emergence of isolates containing these genes in Shiraz medical centers.