Comparison of susceptibility test methods to detect penicillin susceptibility in Streptococcus pneumoniae isolates

The increasing prevalence of penicillin-resistant Streptococuus pneumoniae urges for fast and accurate susceptibility testing methods. This study evaluated the comparability of three commonly used techniques; disk diffusion, E-test and agar dilution, to detect penicillin susceptibility in clinical isolates of S. pneumoniae. Fifty pneumococcal isolates, obtained from patients at the University of Malaya Medical Centre, were selected to include both penicillin-susceptible strains and those that had decreased susceptibility (resistant and intermediate) to penicillin. The minimum inhibitory concentration (MIC) values of penicillin to serve as the reference was determined by the agar dilution method in which, based on the MIC breakpoints recommended by the National Committee for Clinical Laboratory Standards (NCCLS), 27 strains had decreased susceptibility to penicillin with 17 strains resistant and 10 intermediate. Comparing to the agar dilution method, oxacillin disk diffusion test detected all strains with decreased penicillin susceptibility as such while E-test showed a close agreement of susceptibility (92%) of the isolates to penicillin. This confirmed that oxacillin is a good screening test for S. pneumoniae isolates with decreased susceptibility to penicillin while E-test is very reliable for rapid and accurate detection of penicillin susceptibility

The Internet Journalism Disturb Malaysian Social Political Harmony

Internet journalism has been recognized to provide better efficiency on information gathering and adapting to the modernization of technology and life of our society. Dissemination of news and information is more flexible, efficient and instantaneous covering the widest possible audience across geographical barriers and providing medium for public discussion, public opinion and concerns on various aspects such as political, social and economic development. Internet journalism plays important roles in our society nowadays as the medium to influence public opinion, providing forum for discussion especially on issues of public concern, providing critical monitoring of political development, building up the intellectual environment and cultural interest of the public and setting up political agenda. However, issues arise regarding the reliability and capability of internet journalism in reporting and covering few breaking news in Malaysia, the roles of internet journalism in socio-political harmony and the development of media law to control the distribution of news through online medium. Therefore, this paper will investigate the advantages of utilizing internet journalism as a medium for disseminating news and information, their roles in shaping the social and political harmony of our country, issues regarding disturbance caused by internet journalism and the implementation of laws to control news dissemination

The Evolution and Dissemination of Methicillin Resistance Determinant in Staphylococcus aureus

Staphylococcus aureus is an opportunistic pathogen and is frequently associated with the antimicrobial resistance. There has been horizontal gene transfer of Staphylococcus chromosome cassette mec (SCCmec) among the staphylococcal species that colonize a similar colonization niche, which eventually results in emergence of new variant with enhanced survival ability in terms of antimicrobial resistance and virulence level in S. aureus. Evolution and dissemination of SCCmec structure resulted in the emergence of methicillin-resistant S. aureus (MRSA) clones around the world covering hospital, community, and livestock settings. MRSA also has the ability to resist different antibiotic profiles known as multidrug-resistant S. aureus (MDR S. aureus)

Expression analysis of adherence-associated genes in pneumococcal clinical isolates during adherence to human respiratory epithelial cells (in vitro) by real-time PCR.

Pneumococcal virulence determinants have been extensively studied but molecular evidence on virulence gene expression pattern is still lacking. We undertook this study to analyze the regulation pattern of adherence-associated genes; psaA, pspC, cbpG, including ply of serotypes 1, 7F, 19F and 23F clinical isolates during the bacterial adherence to human lung epithelial cells (in vitro), by real-time PCR. We were able to harvest the bacterial RNA (0.5-1 μg μL-1) from the infected host cell and analysis showed a consistent upregulation of psaA. Differential expressions were observed for pspC, cbpG and ply genes but the former was mostly upregulated whereas the later two frequently showed either no significant change or a downregulation. Partial nucleotide sequences of psaA, cbpG and ply were highly homologous among the isolates as well as against GenBank sequences (99%) whereas those for pspC were similar (98%) to allelic variants pspC-3 and pspC-5

A review on Escherichia coli O157:H7-the super pathogen

Shiga-toxin producing Escherichia coli (STEC) are among most important cause of food diseases. More than 70 different serotypes of Shiga-toxin producing E. coli (STEC) that cause disease in humans worldwide have been described. Illnesses range from mild diarrhea to bloody diarrhea to hemorrhagic colitis (HC) and life-threatening Hemolytic Uremic Syndrome (HUS). E. coli O157:H7 is STEC strain most often associated with the most severe form of disease. Infections have been associated with bovine food products, direct animal contact, and bovine manure contamination of vegetables; fruits and drinking water have also been implicated. Epidemiological investigations have implicated food and water as most common vehicle for infections cause by E. coli O157:H7. E. coli O157:H7 has been isolated from surface water and can survive for many weeks in these kinds of environments. It was demonstrated that E. coli O157:H7 can enter the lettuce plant through the root system and migrate throughout the edible portion of the plant. There is an obvious risk of E.coli O157:H7 infection arising from contamination of fruit and vegetable crops grown in soil to which abattoir waste especially where the food products (e.g. salad vegetables) are consumed with minimal processing. E. coli 0157:H7 serotype is considered as being the most significant and has been associated with large food-borne outbreaks in North America, Europe, and Japan. The Centre for Disease Control estimate that E. coli 0157:H7 causes approximately 73,000 illnesses and 61 deaths each year in the USA. After E. coli was recognized as a cause of hemorrhagic colitis, the centers for disease control and prevention (CDC) reviewed over 3,000 E.coli strains serotyped between 1973 and 1983 and found only one O157:H7 isolate. The largest out break to date occurred in Japan in 1996, affecting over 9000 people with contaminated radish sprout as the possible source of infection. Its resist to commonly used antimicrobials generates a public health dilemma. The mini review aims to highlight epidemiology of E. coli O157:H7 and the resultant Public and environmental implications of its continuous existence in our ecosystem

Rapid and reliable identification of meat origin in meat products using CP-M-PCR

A fast and reliable analytical method is necessary to detect adulteration practices in meat-based products in order to provide a sufficient guarantee to protect consumer rights in accordance with European Union and Malaysian Description Act 2011. A single-tube multiplex PCR-based assay namely Common Primer Multiplex PCR (CP-M-PCR), for the detection of meat origin was developed, optimised and used to evaluate the presence of fraudulently added meat in meat products. This effort assists in the detection of pig, ruminant, avian, and rabbit, which multiple target fragments were amplified from mitochondrial NADH dehyrogenase subunit 4 (Nad 4) gene. The designed primers generated specific fragments of 267, 370, 504, and 548 bp lengths for pig, ruminant, avian and rabbit meats, respectively. This system was designed based on the ability of a unique sequence which served as a universal reverse primer and a common forward primer shared by all of the animal groups to amplify the target fragments specifically. The developed system was applied to 42 commercial meat-products and showed the presence of avian meat in analyzed ruminant (1/14), rabbit (1/2) and pig (1/10) samples. CP-M-PCR greatly removed the poor universality and inconsistency of multiplex PCR. Additionally, it provides a rapid, cost-effective and more sensitive method with a detection limit of 0.01 ng of DNA. This highly sensitive, reproducible and practical method could potentially be applied in other areas, such as species identification, bio-security and forensic

Genotyping Approaches for Identification and Characterization of Staphylococcus aureus

Genotyping methods are vital epidemiological tools for discriminating different bacterial isolates within same species, which in turn provide useful data in tracing source of infection and disease management. There have been a revolutionary efforts in ways to distinguish between bacterial types and subtypes at molecular level utilizing DNA in the genomes. Notably, the growth of various DNA typing methods has provided innovative apparatuses for improved surveillance and outbreak investigation. Thus, early identification and genotyping are indispensable as resources for managing therapeutic treatment and the control of rapid expansion of clinically important bacteria. Methicillin-resistant Staphylococcus aureus (MRSA) has been in a great attention due to its contagious nature and subjected to various typing analyses. Thus, in this chapter, we aimed to review the contribution of various genotyping methods of commonly used as well as those unique to staphylococci in understanding its epidemiology, infection and dissemination pattern, and to provide an impression of specific advantages and disadvantages of each tool

Prevalence of Escherichia coli O157:H7 and Enterobacteriaceae on hands of workers in Halal cattle Abattoirs in Peninsular Malaysia

Background: Several occupational diseases of multiple origins are encountered among abattoir workers. Presence of indicator microorganisms (coliforms) on hands of workers can be used a gauge for hygienic practices. Methods: A cross-sectional study was performed to assess the prevalence of E.coli and enterobacteriaceae among Halal abattoir workers in some government halal abattoirs of Malaysia. A total of one hundred and sixty-five hand swab samples were collected from workers of Halal abattoirs in Malaysia. The samples were subjected to microbiological analysis for characterisation and serotyping. Results: The results have shown that no Escherichia coli O157:H7 was isolated on the hands of abattoir workers before and after work. However, a total prevalence of 9.7% was recorded for all samples during work. For non-O157:H7, total prevalence of 33.3% during work and 13% after work were obtained. High prevalence was recorded in sample taken during work from Tampin, Jasin and Kemaman (100% each) while low prevalence where observed in Shah Alam, Banting and Ipoh (20% each). Conclusions: Based on the findings the hygienic practices of hand washing among the workers in few locations was found to be low especially after work

Evaluation of potential public health risk associated with waste water treatment in some Halal abattoirs of Malaysia

Background: Abattoir waste can be detrimental to humans and the environment if proper precautions are put in place. In general, the major environmental problem is linked to abattoir liquid wastes which serve as vehicle for dissemination of pathogenic microorganisms. Epidemiological investigations have implicated food and water as most common vehicle for infections cause by pathogens such as E.coli O157: H7. Method: A cross-sectional study was performed to assess potential health risk of liquid waste disposal from some selected Halal abattoirs in Malaysia. A total of 120 waste water samples were collected. Total coliform count was performed to determine the levels of pollution before and after filtration. Cultural, Biochemical and serological tests were used for identification and characterization of the isolates. Results: Results showed that the abattoir located in Dungun in Terranganu region had the highest cfu/ml before (2200) and after waste water filtration while Senawang abattoir in Negeri Sembilan had the lowest. Highest occurrence rate of E.coli were recorded in Shah Alam, Banting and Tampin(40% each). Non-O157: H7 Escherichia coli were found to be present in almost all the abattoirs before waste water filtration. Samples collected after discharge revealed that five of the abattoirs had 100%. Other pathogenic bacteria isolated from the abattoirs include Salmonella entritidis and Citrobacter freundii. Findings: Occurrence of pathogenic bacteria coupled with increased total bacteria count have indicated alarming risk of dissemination of harmful bacterial into the environment. Conclusion: Effectiveness of waste water treatment was found to be very low in most of the abattoirs from the assessment

Multiple ambler class A ESBL genes among Klebsiella pneumoniae isolates in a Malaysian district hospital

Detailed reports regarding the distribution and activity of extended-spectrum beta-lactamase (ESBL)-producing Klebsiella pneumoniae isolates are currently not widely available in the Malaysian setting. This study was conducted to determine the ESBL genes distribution rate, phenotypic detection, and antimicrobial susceptibility patterns among beta-lactam resistant Klebsiella pneumoniae isolated from a Malaysian district hospital. K. pneumoniae isolates were collected from a microbiology laboratory at Hospital Pakar Sultanah Fatimah, Malaysia. Following exclusion and inclusion criteria, 141 isolates were selected for this study. K. pneumoniae was identified by phenotypic method, whilst antibiotics' susceptibility patterns were determined by the Kirby-Bauer method, as described in Clinical Laboratory Standard Institute (CLSI) guidelines (Oxoid, UK; Becton-Dickenson, USA). Detection of Ambler Group A ESBL gene (blaSHV, blaTEM, blaCTX-M-1, blaCTX-M-2, blaCTX-M-8, blaCTX-M-9, and blaCTX-M-25) was done using polymerase chain reaction (PCR). ESBL genes were found in 85.8% of K. pneumoniae (121 of 141) isolates. Only blaSHV, blaTEM, blaCTX-M-1, and blaCTX-M-9 were detected among K. pneumoniae isolates with distribution rates of 75.2% (106 of 141), 41.1% (58 of 141), 44% (62 of 141), and 0.7% (1 of 141), respectively. There was no blaCTX-M-2, blaCTX-M-8, or blaCTX-M-25 detected from any isolates in this study. Sequencing of representative amplicons revealed blaSHV as SHV-12, blaTEM as TEM-1, blaCTX-M-1 as CTX-M-15, and blaCTX-M-9 as CTX-M-18. The phenotypic detection rate of ESBL was 71.6% (101 of 141), whilst 9.2% (13 of 141) were positive for carbapenemase. AmpC beta-lactamase was detected in 22% (31 of 141) of all isolates. Antibiotic resistance was between 44.6% (netilmicin) and 97.2% (cefotaxime). Based on ESBL genes distribution, blaSHV was a predominant gene found in one of Malaysian district hospitals, notwithstanding having blaTEM, blaCTX-M-1, and blaCTX-M-9. Despite carrying multiple ESBL genes, some strains were positive for carbapenemase or AmpC beta-lactamase, which resulted in high antimicrobial resistance rates