Abstract

Background and Objective: Methicillin-resistant Staphylococcus aureus (MRSA) is a major pathogen involved in nosocomial infections. Because of increasing antibiotic resistance of these strains, treatment of these infections has become very difficult. This study aimed to determine the frequency and drug resistance pattern of MRSA isolates from nosocomial infections in hospitals.

Material and Methods: the isolates of S.aureus (n= 100) isolated from clinical samples such as: urine, blood, wound, throat, sputum, cerebrospinal fluid, catheter and other purulent discharge from in patients were identified using biochemical tests. MRSA strains were isolated by using agar screening method and then drug resistance pattern of them was determined by disk diffusion method.

Results: Out of 100 S.aureus strains, 65 (65%) were MRSA. Drug resistance of MRSA isolates to most antibiotics were high: penicillin100%, oxacillin 100%, nitrofurantoin 80%, tetracycline 63%, erythromycin 58.4%, gentamicin 46.1%, clindamycin 33.8%, cotrimoxazole 35.3% and ciprofloxacin 26.1%. Also 35 of MRSA isolates were multiple drug resistance (MDR).

Conclusion: The prevalence of MRSA isolates and also their resistance to other antibiotics were high.

Keywords: Drug Resistance, Methicillin-Resistant Staphylococcus Aureus, Multi-Drug Resistant

ABSTRACT

           Background and Objectives: Hepatitis A virus (HAV) enters sewage through the stool of infected patients and contaminates freshwater and seawater. The aim of present study was quantitative molecular detection of HAV in raw and treated urban sewage samples from Isfahan, center of Iran.
           Material and methods: Sewage samples were collected from six urban treatment plants in cold and warm weather, between December 2016 and Jun 2017. Physicochemical indicators were measured immediately after sampling. Viral particles were isolated and concentrated by modified adsorption-elution method using Al³⁺-coated filters. Quantitative PCR was done for amplification of a fragment in the highly conserved 5′ noncoding region of the HAV genome.
           Results: Although the values of the indicators were lower in 67-83% of sewage samples in warm weather, no significant difference was detected between the physicochemical indicators of sewage samples. HAV was detected in three raw sewage samples collected in cold weather (copy number of 32590, 28400 and 14200 per µl) and in one treated sewage sample (copy number of 6500 per µl) collected in cold weather. Positive HAV sewage samples had been treated by activated sludge and aerated lagoon.
           Conclusion: We detected high frequency of HAV in raw urban sewage samples from Isfahan, Iran. This highlights the importance of paying extra attention to irrigation of farms with raw sewage. Based on the results of this study and previous studies, it can be concluded that the activated sludge system may be more effective for elimination of enteric viruses, such as HAV.
           Keywords: Hepatitis A virus, Sewage, Weather.

     Leptospirosis is a zoonotic disease with a high incidence rate in many parts of the world due to the presence of various hosts for the pathogenic Leptospira. Tropical, subtropical and humid regions are suitable for long-term survival of the bacterium. Because of the temperate and humid climate, northern areas of Iran are suitable for pathogenic Leptospira and outbreak of the disease. Therefore, identification of infected areas is important from a public health and economic point of view. Previous studies show that the incidence rate of leptospirosis is increasing every year. Therefore, accurate diagnosis, control and prevention of this disease seem necessary through vaccination and raising public awareness, especially among high-risk groups. Today, diagnostic methods including immunofluorescence assay, enzyme-linked immunosorbent assay, microscopic agglutination test (MAT) and polymerase chain reaction (PCR) are used to diagnose the leptospirosis. MAT is the gold standard test for the diagnosis of leptospirosis with extensive applications in Iran. Due to the importance of this disease and its high prevalence in recent years, the present study aimed to investigate the epidemiology and diagnosis of leptospirosis in Iran.