Browsing by Author "Bazzi, Ali M."

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    Comparison among four proposed direct blood culture microbial identification methods using MALDI-TOF MS
    (Elsevier, 2017-05) Bazzi, Ali M.; Rabaan, Ali A.; El Edaily, Zeyad; John, Susan; Fawarah, Mahmoud M.; Al-Tawfiq, Jaffar A.; Department of Medicine, School of Medicine
    Matrix-assisted laser desorption-ionization time-of-flight (MALDI-TOF) mass spectrometry facilitates rapid and accurate identification of pathogens, which is critical for sepsis patients. In this study, we assessed the accuracy in identification of both Gram-negative and Gram-positive bacteria, except for Streptococcus viridans, using four rapid blood culture methods with Vitek MALDI-TOF-MS. We compared our proposed lysis centrifugation followed by washing and 30% acetic acid treatment method (method 2) with two other lysis centrifugation methods (washing and 30% formic acid treatment (method 1); 100% ethanol treatment (method 3)), and picking colonies from 90 to 180 min subculture plates (method 4). Methods 1 and 2 identified all organisms down to species level with 100% accuracy, except for Streptococcus viridans, Streptococcus pyogenes, Enterobacter cloacae and Proteus vulgaris. The latter two were identified to genus level with 100% accuracy. Each method exhibited excellent accuracy and precision in terms of identification to genus level with certain limitations.
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    Comparison of Effectiveness of Germania Honey Compared to Manuka Honey in Methicillin-Resistant Staphylococcus aureus (MRSA) Killing
    (Bentham, 2019) Bazzi, Ali M.; Rabaan, Ali A.; Al-Tawfiq, Jaffar A.; Shannak, Bilal M.; Medicine, School of Medicine
    Purpose: Manuka honey is currently used in medical-grade sterile wound treatment products and has been shown to be effective in methicillin-resistant Staphylococcus aureus (MRSA) killing in vitro and in wound healing in a number of case studies and series. Locally produced honey in Pakistan and Chile have been proposed to be as effective as Manuka honey in bacterial killing in vitro, presenting potentially more accessible and affordable alternatives. In this study, we compared the effectiveness of a local Germania honey from Saudi Arabia to Manuka honey MGO 550 for in vitro killing of MRSA. Methodology: Overnight Muller Hinton broth cultures of 50 wound culture isolates of MRSA from 50 patients were incubated with a series of dilutions of Manuka honey MGO 550 and corresponding Germania honey dilutions for 24 h. Turbidity was assessed to determine whether bacterial growth had occurred, and no growth was confirmed by a further 24 h sub-culture on blood agar. Results/Key findings: Manuka honey MGO 550 was significantly more effective than Germania honey at MRSA killing at 100% v/v, 50% v/v and 25% v/v (p=0.025, 0.000265, and 0.000112 respectively) Conclusion: Manuka honey MGO 550 is significantly more effective in killing MRSA in vitro than Germania honey. Germania honey does not appear to be a promising locally produced alternative to Manuka honey for the development of honey-based wound dressings. Further experiments could determine if Germania honey is effective against other bacterial species.
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    Direct identification and susceptibility testing of positive blood cultures using high speed cold centrifugation and Vitek II system
    (Elsevier, 2017-05) Bazzi, Ali M.; Rabaan, Ali A.; Fawarah, Mahmoud M.; Al-Tawfiq, Jaffar A.; Department of Medicine, School of Medicine
    Compared to routine isolated colony-based methods, direct testing of bacterial pellets from positive blood cultures reduces turnaround time for reporting of antibiotic susceptibility. The aim of this study was to compare the accuracy, and precision, of a rapid method for direct identification and susceptibility testing of blood cultures with the routine method used in our laboratory, using Vitek 2. A total of 60 isolates were evaluated using the candidate and the routine method. The candidate method had 100% accuracy for the identification of Gram negative bacteria, Staphylococcus and Enterococcus, 50% for Streptococcus and 33.3% for Corynebacterium species. Susceptibility testing of Gram negative isolates yielded 98–100% essential agreement. For Staphylococcus and Enterococcus isolates, essential agreement was 100% for 17 antibiotics except for moxifloxacin. Direct testing of blood culture samples with Vitek 2 produced reliable identification and susceptibility results 18–24 h sooner for aerobic/anaerobic facultative Gram-negative bacteria and Gram-positive Staphylococcus and Enterococcus strains.
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    Dynamics of scientific publications on the MERS-CoV outbreaks in Saudi Arabia
    (Elsevier, 2017-11) Rabaan, Ali A.; Al-Ahmed, Shamsah H.; Bazzi, Ali M.; Al-Tawfiq, Jaffar A.; Medicine, School of Medicine
    Middle East Respiratory Syndrome Coronavirus (MERS-CoV) is an emerging disease with a relatively high case fatality rate. Most cases have been reported from Saudi Arabia, and the disease epidemic potential is considered to be limited. However, human–human transmission has occurred, usually in the context of healthcare facility-associated outbreaks. The scientific and medical community depends on timely publication of epidemiological information on emerging diseases during outbreaks to appropriately target public health responses. In this review, we considered the academic response to four MERS CoV outbreaks that occurred in Al-Hasa in 2013, Jeddah in 2014 and Riyadh in 2014 and 2015. We analysed 68 relevant epidemiology articles. For articles for which submission dates were available, six articles were submitted during the course of an outbreak. One article was published within a month of the Al-Hasa outbreak, and one each was accepted during the Jeddah and Riyadh outbreaks. MERS-CoV epidemiology articles were cited more frequently than articles on other subjects in the same journal issues. Thus, most epidemiology articles on MERS-CoV were published with no preferential advantage over other articles. Collaboration of the research community and the scientific publishing industry is needed to facilitate timely publication of emerging infectious diseases.
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    Molecular aspects of MERS-CoV
    (Springer Nature, 2017) Rabaan, Ali A.; Bazzi, Ali M.; Al-Ahmed, Shamsah H.; Al-Tawfiq, Jaffar A.; Medicine, School of Medicine
    Middle East respiratory syndrome coronavirus (MERS-CoV) is a betacoronavirus which can cause acute respiratory distress in humans and is associated with a relatively high mortality rate. Since it was first identified in a patient who died in a Jeddah hospital in 2012, the World Health Organization has been notified of 1735 laboratory-confirmed cases from 27 countries, including 628 deaths. Most cases have occurred in Saudi Arabia. MERS-CoVancestors may be found in OldWorld bats of the Vespertilionidae family. After a proposed bat to camel switching event, transmission of MERS-CoV to humans is likely to have been the result of multiple zoonotic transfers from dromedary camels. Human-to-human transmission appears to require close contact with infected persons, with outbreaks mainly occurring in hospital environments. Outbreaks have been associated with inadequate infection prevention and control implementation, resulting in recommendations on basic and more advanced infection prevention and control measures by the World Health Organization, and issuing of government guidelines based on these recommendations in affected countries including Saudi Arabia. Evolutionary changes in the virus, particularly in the viral spike protein which mediates virus-host cell contact may potentially increase transmission of this virus. Efforts are on-going to identify specific evidence-based therapies or vaccines. The broad-spectrum antiviral nitazoxanide has been shown to have in vitro activity against MERS-CoV. Synthetic peptides and candidate vaccines based on regions of the spike protein have shown promise in rodent and non-human primate models. GLS-5300, a prophylactic DNA-plasmid vaccine encoding S protein, is the first MERS-CoV vaccine to be tested in humans, while monoclonal antibody, m336 has given promising results in animal models and has potential for use in outbreak situations.
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    Overview of Zika infection, epidemiology, transmission and control measures
    (Elsevier, 2017-03) Rabaan, Ali A.; Bazzi, Ali M.; Al-Ahmed, Shamsah H.; Al-Ghaith, Mohamed H.; Al-Tawfiq, Jaffar A.; Medicine, School of Medicine
    The current Zika virus outbreak in the Americas and the proposed link to increases in microcephaly and neurological disorders have prompted the World Health Organization to declare a Public Health Emergency of International Concern on February 1, 2016. The virus is transmitted by Aedes mosquitoes and potentially by transfusion, perinatal and sexual transmission. The potential for spread into countries where Aedes mosquitoes are endemic is high. Previously, cases tended to be sporadic and associated with mild, non-specific symptoms. Prior outbreaks occurred in Yap Island in Micronesia in 2007, the first time Zika arose outside of Africa and Asia, and in French Polynesia in 2013. A birth data review has confirmed that the latter outbreak was followed by an increase in microcephaly cases. A coordinated international response is needed to address mosquito control; expedite development of diagnostic tests, vaccines and specific treatments for Zika; and address the proposed link to microcephaly and neurological diseases.