Acta Microbiologica Hellenica 2019 (Volume 64, Issue 1)

Virological surveillance of influenza in North Greece, 2017/18

Angeliki Melidou, Maria Exindari, Georgia Gioula, Suzana Vergkizi-Nikolakaki, Maria Christoforidi, Anastasia Andreopoulou, Theano Georgakopoulou, Anna Papa-Konidari

Department of Microbiology, School of Medicine, Aristotle University of Thessaloniki (National Influenza Centre for N. Greece)

Influenza is an important issue of public health, due to its yearly outbreaks. The present study presents the results of influenza laboratory testing performed by the National Influenza Centre for N. Greece during the 2017-18 season. From the 40th week 2017 to the 20th 2018 740 specimens were tested. The specimens belonged to ILI patients (Sentinel surveillance system) as well as to patients hospitalised in wards and ICUs. One hundred eighty one positive samples were detected and they were then cultured in MDCKSIAT cells and in embryonated hen eggs. The detected viral types/subtypes were Α(Η1Ν1)pdm09, Α(Η3Ν2) and Β. Type B Yamagata lineage viruses strongly predominated (75% of positives), while the circulation of Α(Η3Ν2) viruses was very small (3.3% of positives). Fifteen fatalities were reported. Out of them, 5 were caused by Α(Η1Ν1)pdm09 and 10 by B viruses. The overall mean age was 63.3 years. The specific mean ages were 55 and 67.5 years for Α(Η1Ν1)pdm09 and B viruses respectively. For most of the fatal cases pre-existing medical conditions were reported. The molecular analysis of the haemagglutinin of representative strains was performed in order to investigate the viral evolution and to evaluate the vaccine effectiveness. The revealed mutations and amino acid substitutions indicate an antigenic affinity of the Α(Η1Ν1)pdm09 to the vaccine strain and an antigenic divergence of the Α(Η3Ν2) strains from it. The strains belonged to Yamagata lineage, which was not included in the trivalent vaccine of the 2017-18 influenza season, thus resulting to low vaccine effectiveness. Furthermore, the molecular analysis revealed two Α(Η1Ν1)pdm09 strains having the H275Y mutation leading to viral resistance to neuraminidase inhibitors (oseltamivir). As suggested by the WHO, constant surveillance of influenza viruses is necessary at national and global level.

Key words: influenza, Α(Η1Ν1)pdm09, Α(Η3Ν2), Β, vaccine, resistance

Testing level of immunity against measles in personnel of pediatric hospital and complementary vaccination

Nikolaos Giormezis,1Vasiliki Diamanti,2 Anastasia Aggelatou,1 Aikaterini Gatopoulou1,3

1Department of Microbiology, 3President of Hospital Infections Committee, “Karamandaneion” Children’s Hospital, Patras. 2Biopathologist, Patras.

Measles is a viral, highly contagious disease, accompanied by fever and skin rash. Adults suffer more rarely than children, but with more severe symptoms. Around 30% of patients will develop one or more complications, some of which are very serious. Since 2017, measles outbreaks have occurred in Europe and Greece due to incomplete or absent immunization. People who work at healthcare services are often included among those who have not been vaccinated at all or who are not fully vaccinated. According to KEELPNO, those who are born after 1970 and did not undergo measles in the past or have not been vaccinated with two doses of MMR or have not confirmed that they are immune should be vaccinated immediately. The main goal of this study was the serological testing for measles of people who work at “Karamandaneio” Children’s Hospital of Patras and have been born after 1970 and the complete vaccinationof the subject to disease personnel, due to the measles outbreak, especially in Southern Greece and the direct or indirect contact of the personnel with significant number of young patients who come at the outpatients department or those who are hospitalized with measles, in the only pediatric hospital outside of Attica in our country. 73 people, who work at “Karamandaneio” Children’s Hospital, under 48 years old, were tested in the Immunology Laboratory of the department of Microbiology for IgG antibodies against measles virus with SERION ELISA classic Measles Virus IgG/IgM method. Title of IgG antibodies >200 mIU/ml was considered positive for immunity, 150-200 mIU/ml as grey zone and <150 mIU/ml as negative. From the 73 people of the hospital personnel tested, 59 (80.82%) were found immune (IgG+) against measles, one (1.37%) had antibody title in the grey zone and 13 (17.81%) were not immune (IgG-) and were fully vaccinated with MMR. Despite the measles outbreak in our area and the continuous admission of children with measles in “Karamandaneio” Children’s Hospital of Patras, the only pediatric hospital outside of Attica in our country, and in spite of the high percentage (19.18%) of the subject to disease personnel in our pediatric hospital, no one from the hospital stuff suffered from measles, thanks to the serological testing and the immediate complete vaccinations (MMR), which is the only protection strategy for the creation of herd immunity and the elimination of a reemerging disease. Key words: Measles, serological testing, immunity, subject to disease personnel, Pediatric Hospital, vaccination

Increase resistance towards colistin in carbapenem-resistant Enterobacteriaceaestrains in a tertiary hospital, Quito, Ecuador

Santiago Moisés Garrido, David Israel Garrido, Leonel Rene Calvopiña, Betty Elizabeth Marcillo, Patricia del Carmen Ramírez, Gina Vivas

Hospital de Especialidades de las Fuerzas Armadas N1, Microbiology Department, Quito-Ecuador

The aim of the current study was to present the increased resistance in carbapenem-resistant Enterobacteriaceae strains towards colistin.An observational, descriptive study, based on the analysis of microbiological reports of carbapenemase-producing strains from 2015 to June 2018 in the Microbiology Department of the Hospital de Especialidades de las Fuerzas Armadas N°1 in Quito, Ecuador, was carried out. Between 2015 and June 2018, carbapenemase-producing strains infected 67 patients, in total. Among them, males (57.89% to 81.82%), and people older than 60 years (57.33% to 90.91%), were mostly affected by the infection. Further, the most frequent pathogen isolated was Klebsiella pneumoniae (57.69% to 93.33%), followed by K. oxytoca, Enterobacter cloacae, Escherichia coli, Citrobacter freundii,and Serratia marcescens. However, a reduction in the number of patients affected through the years, 24 in 2015, 19 in 2016, 13 in 2017, and 11 in 2018, was witnessed. In all the isolates, carbapenemase blaKPC-type producing strains with 100 % resistance towards aminopenicillins alone or combined with beta-lactamase inhibitors, ureidopenicillin, cephalosporins, ciprofloxacin, and carbapenems, were discovered. On the contrary, aminoglycosides and colistin exhibited variable resistance patterns. In the current investigation, emerging resistance to colistin in K. pneumoniaein 2017 and 2018 was observed, upon being compared with the year 2015 and 2016. The observations, in the current study, are similar to other reports that show the emerging resistance to colistin. However, more studies are required to determine the impact of this problem in public health.

Key words: Carbapenem-Resistant Enterobacteriaceae; Colistin; Resistance


phtalazine and bis-pyrazole’ tags=”]
Masoud Hamidi1,2, Nahid Ramezanpour2, Fatemeh Karimitabar1,2,*, Ardeshir Khazaei3, Mohammad Ali Zolfigol3, Iraj Nikokar2, Rasool Mirzaei2, Afshin Vanak Araghian2

1Food and Drug Research Center, Vice-Chancellery of Food and Drug, Guilan University of Medical Sciences, Rasht, Iran; 2Medical Biotechnology Research Center, Faculty of Paramedicine, Guilan University of Medical Sciences, Rasht, Iran; 3Faculty of Chemistry, Bu-Ali Sina University, Hamedan, Iran

In recent years, due to a sharp increase of antibiotic resistance, synthesized derivative compounds have been considered as a superseded source for new drugs. With regard to the high therapeutic behavior of isatin derivatives from many aspects of drug discovery, in this study, the antibacterial effects of newly synthesized derivatives of pyranopyrazole, pyrazolo[1,2-b]phtalazine and bis-pyrazole against Bacillus cereus, Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureusand Enterococcus faecaliswere examined. Twelve individual compounds were weighted and prepared at a final concentration of 1 mg/mL in dimethyl sulfoxide (DMSO). Bacterial test organisms were maintained in nutrient agar slants at 4ºC and subcultured in Petri plates prior to use. The tested compounds are randomly added into the wells with a 100 μl volume on the plate under sterile condition and then were incubated at 37ºC for 24 hours. All experiments were repeated three times and the mean values are reported as the results. The antibacterial effects of the compounds that produced ≥ 8mm zone of inhibition were tested quantitatively by Micro broth dilution method for determination of minimal inhibitory concentration (MIC) value. After incubation overnight, the first tube with clean appearance determined the MIC. According to the results, the MIC of the compounds defined as cand dagainst S. aureusis 64 (μg/ml). It is found that the synthesized compounds are only effective against S. aureus. The comparison of the maximum zone of inhibition (22±0.4) and MICs between the present study and those in literature, shows the privilege of using compound cand d against S. aureus.

Key words: Antibacterial activity; Antibiotic resistance; Maximum zone of inhibition; Minimum inhibitory concentration (MIC); Isatin

Characterization of efflux pump-mediated resistance against fluoroquinolones among clinical isolates of Pseudomonas aeruginosa in the northeast of Iran and its association with mortality of infected patients

Maedeh Amiri Rudy1, Samaneh Dolatabadi1, Hosna Zare2,3,4, Kiarash Ghazvini2,3*
1Department of Microbiology, School of Medicine, Islamic Azad University of Neyshabur
2Antimicrobial Resistance Research Center, Mashhad University of Medical Sciences, Mashhad, Iran.
3Department of Microbiology and Virology, school of Medicine, Mashhad University of Medical Sciences,
Mashhad, Iran.
4Student Research Committee, Mashhad University of Medical Sciences, Mashhad, Iran.

Pseudomonas aeruginosa is an opportunistic human pathogen which causes serious nosocomial infections with a high level of resistance. Fluoroquinolone resistance is mostly due to efflux pumps and target mutations. Multidrug-efflux transporter MexB in MexAB-OprM pump is a mechanism for this resistance. The present study aimed to investigate the prevalence of resistance against fluoroquinolones among clinical isolates of P. aeruginosa in Mashhad, Iran.
This cross-sectional study was performed on 150 Pseudomonas aeruginosa isolates from hospitalizedpatients in burn and intensive care units of the two main hospitals of Mashhad. The bacteria were identified primarily based on biochemical tests. Then antibiotic susceptibility was studied by disk diffusion method against 11 antibiotics, and minimum inhibitory concentration (MIC) was measured for ciprofloxacin, levofloxacin, and ofloxacin. Finally, the presence
of mexB gene was evaluated using PCR method. One hundred thirty-two isolates (88%) were multidrug resistant, 8 isolates (5.3%) were completely
susceptible, and 10 isolates (6.6%) were totally drug resistant. We detected 76 (50.8) ciprofloxacin-resistant isolates and all of them were resistant to one or more other tested antibiotics. Based on the PCR results, 42% of clinical isolates had the mexB gene and mexAB-oprM operon, and this pump was more prevalent (80%) among ciprofloxacin-resistant isolates. In conclusion in this study, ciprofloxacin and multidrug resistance due to the efflux pumps were
frequent. Based on our results, there is a strong association between mexB gene and the mortality of patients.

Key words: Pseudomonas aeruginosa, Fluoroquinolone,Resistance, mexB, Efflux pump

In silicoanalysis of tetracycline resistance in Acinetobacter baumannii and its protein diversity

Vijayashree Priyadharsini J1, Smiline Girija AS2, Paramasivam A1

1Biomedical research unit and laboratory animal centre-Dental research cell (BRULAC-DRC), Saveetha Dental College, Saveetha Institute of Medical and Technical Sciences [SIMATS], Saveetha University, Poonamallee High Road, Chennai – 600 077, Tamilnadu, India 2Department of Microbiology, Saveetha Dental College, Saveetha Institute of Medical and Technical Sciences [SIMATS], Saveetha University, Poonamallee High Road, Chennai – 600 077, Tamilnadu, India

Resistance towards antimicrobial drugs have posed a serious threat to mankind. Acinetobacter baumannii, a nosocomial pathogen have been spotted to hold a bunch of drug resistant genes which serves as an armour to escape from antimicrobial drugs commonly used for treatment. The present study describes the tetracycline resistant phenotype encountered in A. baumannii and its evolutionary relatedness with other bacterial species.  A small subset of genome sequence from Acinetobacter sp.was probed to assess the frequency of tetracycline-resistant phenotype by in silicoamplification. Further, the protein sequences of PCR-positive genes were subjected to multiple sequence alignment, to deduce the phylogenetic relationship across several other bacterial species. Thetet(B) gene was found to occur in a greater frequency (42.1%) followed by tet(A) (10.5%),among eleven different tetgenes analysed. The tet(A)gene was found in strains harbouring plasmids and tet(B)was observed in plasmid-bearing strains as well as one strain devoid of plasmids. Multiple sequence alignment and phylogenetic analysis of the protein sequences revealed an evolutionary closeness oftet(A) and tet(B) from A. baumannii to E. coliand P . stuartii respectively. A basic understanding on the molecular mechanisms underlying drug-resistant phenotype would eventually lead to the assessment of new drug targets. An evolutionary analysis of proteins encoding drug resistance might be useful to target closely related pathogens which enable the discovery of broad spectrum drugs targeting multiple pathogens.

 Key words: A.baumannii, tetracycline, PCR, phylogenetic analysis