Papers by Patrick Eberechi Akpaka
West Indian Medical Journal, Oct 1, 2007
Microorganisms, Sep 4, 2023
Biotechnology journal international, Jun 9, 2023
In this paper, the main objective was to raise chickens' antibodies against three crucial public ... more In this paper, the main objective was to raise chickens' antibodies against three crucial public health microorganisms: the human immunodeficiency virus-1, Salmonella spp, and Staphylococcus aureus. Immunogens were prepared from the said microorganisms. Chickens were vaccinated either orally or intramuscularly. After a booster immunization, mostly eggs were collected and assess for the presence of specific antibodies. The most important results were the production of a large amount of anti-HIV antibodies in chicken's eggs, and also the synthesis of anti-protein a antibodies with the ability to inhibit the growth of S. aureus in vitro and to serve as anti-anti-idiotypic antibodies with the capacity of neutralizing the original antigen. Enzyme-linked immune absorbent assays detected the presence of these antibodies as anti-Salmonella antibodies that were critical in reducing the bacterial load in the stomach and caeca compared with a control group. The vaccines were effective and safe, but more laboratory work, and economics have to be carried out to start a human trial.
Microbiology Spectrum, 2014
Produce contains high levels of mixed microflora, including coliforms and Escherichia coli , but ... more Produce contains high levels of mixed microflora, including coliforms and Escherichia coli , but occasionally pathogens may also be present. Enterotoxigenic E. coli and Shigatoxin-producing E. coli (STEC) have been isolated from various produce types, especially spinach. The presence of STEC in produce is easily detected by PCR for the Shiga toxin (Stx) gene, stx , but this is insufficient for risk analysis. STEC comprises hundreds of serotypes that include known pathogenic serotypes and strains that do not appear to cause severe illness. Moreover, Stx without a binding factor like intimin (encoded by eae ) is deemed to be insufficient to cause severe disease. Hence, risk analyses require testing for other virulence or serotype-specific genes. Multiplex PCR enables simultaneous testing of many targets, but, in a mixed flora sample, not all targets detected may be coming from the same cell. The need to isolate and confirm STEC in produce is critical, but it is time- and labor-intensi...
Journal of Clinical Microbiology, Feb 1, 2013
PubMed, Mar 1, 2022
Vaginal Candidiasis and associated epidemiological risk factors prevalent among a cross section o... more Vaginal Candidiasis and associated epidemiological risk factors prevalent among a cross section of pregnant women attending tertiary hospital in Trinidad and Tobago was evaluated. Standardized questionnaire was used to survey 492 pregnant women over a period of 10 months in 2019. Vaginal swab was collected and processed using standard microbiological laboratory methods for phenotypic identification. Data were analyzed using SPSS to identify potential risk factors. Chi-squared (ê“2) test and logistic regression tests examined associations and odds ratios with corresponding 95% confidence intervals. Prevalence of vulvovaginal candidiasis was 44.9% with Candida albicans as predominant species identified (62%, N=492). Vaginal candidiasis was statistically significant for several risk factors, including second trimester (p = 0.03), age group 26 - 34 years (p=003), history of masturbation especially during the last 48hours prior to the swabbing (p=0.05), and wearing of pants as opposed to skirt clothes (p=0.04). In conclusion, several epidemiological risk factors are associated vaginal candidiasis among cross section of pregnant women in the country. Patient education, microbiological investigations and appropriate treatment will improve antenatal healthcare delivery in the country.
Antibiotics, Jun 14, 2023
This article is an open access article distributed under the terms and conditions of the Creative... more This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY
International Journal of Community Medicine and Public Health, Jun 23, 2017
Several studies have shown varying trends in knowledge about infection control based on a group o... more Several studies have shown varying trends in knowledge about infection control based on a group of HCW and their years of experience. 6,7 Recent literatures also found differences in terms of actual knowledge of infection transmission and control, its understanding and application by HCW. 8,9 Internationally, it is crucial that effective infection prevention strategies associated with health care are implemented in order to achieve optimum response to disease outbreaks and by extension overall ABSTRACT Background: The objective of the study was assessment of knowledge, attitudes, and practices (KAP) towards infection prevention among healthcare workers (HCW) in Trinidad and Tobago. Methods: A cross-sectional study was conducted among 300 HCWs from three regional hospitals in Trinidad and Tobago about their knowledge, attitude, and practice towards infection prevention in the country. All information's were collected through interview using structured questionnaires. The data was collected from April to June 2016; thoroughly checked and cleaned for completeness before analysis with SPSS version 20 statistical software. The 95% confident interval and the p value were used to check for association between the dependent and independent variables. A p value of <0.05 was considered statistically significant. Finally, the findings of the study were explained using tables. Results: A total of 300 HCW participated in the study, with a 100% response rate. In this study only 20.3% respondents were knowledgeable, 46.7% had good attitude and 44% had good practices toward infection prevention, suggesting less than satisfactory scores in this study. Conclusions: The results highlight generally poor knowledge, attitudes and practices towards infection prevention in the three hospitals in Trinidad and Tobago. Therefore, policies and measures should be put in place to ensure regular training programs for HCW, providing strong understanding and a positive outlook on infection prevention.
African Journal of Microbiology Research, May 7, 2019
Conventional commercially available rapid immuno-chromatographic tests (ICTs) or diagnostic kits ... more Conventional commercially available rapid immuno-chromatographic tests (ICTs) or diagnostic kits were evaluated for their sensitivity, specificity, cost and turnaround time (TAT) results with Dengue IgM/IgG capture enzyme linked immunosorbent assays (ELISA) as the standard test, in blood samples from a cross-section of individuals with clinical features suggestive of dengue fever attending health care facilities in the country. Blood samples taken from over 100 consented participants were analyzed using the two rapid ICTs (SD Bioline Dengue Duo NS1/IgM/IgG and Panbio Dengue Duo Cassette) and compared with the Dengue IgM/IgG capture ELISAs. Standardized questionnaire was used to obtain bio and epidemiological data of the participants. The laboratory evaluation also assessed the TAT to complete the tests as well as the cost for each test method. The laboratory analysis on a given number (n=93) revealed that the SD Bioline was more sensitive (39.9%) than the Panbio (22.1%; p=0.005), and specificities for both were 100%. The SD Bioline includes an extra biomarker test with the same TAT and differs in cost by USD$ 1.14 as opposed to the Panbio. The ELISA has a cost of USD$ 8.07 and despite its longer TAT, it has the advantage of running more samples (1 vs 96) at a given time. While SD Bioline may be the better choice with a higher sensitivity, dengue ELISAs should also be favourably considered as an option for diagnostic purposes. In a resource strapped setting like the laboratories in Trinidad and Tobago, the ELISA should be preferred because its sensitivity and specificity were higher than the Panbio and SD Bioline kits. Besides, more samples were tested giving an effective TAT for amounts of samples completed despite a higher cost.
Advances in medicine, 2016
Geographic spread of vancomycin-resistant enterococci (VRE) clones in cities, countries, or even ... more Geographic spread of vancomycin-resistant enterococci (VRE) clones in cities, countries, or even continents has been identified by molecular techniques. This study aimed at characterizing virulent genes and determining genetic relatedness of 45 VRE isolates from Trinidad and Tobago using molecular tools, including polymerase chain reaction, pulsed-field gel electrophoresis (PFGE), and Random Amplification Polymorphic DNA (RAPD). The majority (84%) of the isolates were Enterococcus faecium possessing vanA gene while the rest (16%) were Enterococcus faecalis possessing vanB. The esp gene was found in all 45 VRE isolates while hyl genes were found only in E. faecium species. The E. faecium species expressed five distinct PFGE patterns. The predominant clones with similar or common patterns belonged to clones one and three, and each had 11 (29%) of the VRE isolates. Plasmid content was identified in representative isolates from each clonal group. By contrast, the E. faecalis species had one PFGE pattern suggesting the presence of an occult and limited clonal spread. The emergence of VRE in the country seems to be related to intra/interhospital dissemination of an epidemic clone carrying the vanA element. Therefore, infection control measures will be warranted to prevent any potential outbreak and spread of VRE in the country.
European Journal of Clinical Microbiology & Infectious Diseases, Nov 9, 2011
Eighty methicillin-resistant Staphylococcus aureus (MRSA) isolates from three hospitals in Trinid... more Eighty methicillin-resistant Staphylococcus aureus (MRSA) isolates from three hospitals in Trinidad and Tobago were collected and genotyped using microarray hybridisation. They were found to belong to three distinct MRSA strains. Of the 80 isolates, 76 were assigned to ST239-MRSA-III. They were largely homogeneous, although some variations affected the presence of the enterotoxin A gene, as well as of resistance markers (mercury resistance operon, aadD, tet(K), qacA). The mupA gene conferring mupirocin resistance was found in 7.3% of isolates. One isolate was identified as CC5-MRSA-II and three isolates belonged to the Panton-Valentine leukocidin (PVL)-positive ST8-MRSA-IV strain USA300. While community-acquired MRSA strains are rare in Trinidad and Tobago, the vast majority of MRSA cases can be attributed to healthcare-associated strains. Thus, infection control procedures within medical facilities need to be revised and enforced. This could substantially reduce the burden of MRSA to healthcare in Trinidad and Tobago.
International Journal of Infectious Diseases, Nov 1, 2007
Objectives: Methicillin-resistant Staphylococcus aureus (MRSA), first reported in a British hospi... more Objectives: Methicillin-resistant Staphylococcus aureus (MRSA), first reported in a British hospital in the early 1960s, has now reached global proportions. Geographic spread of one or several MRSA clones in a city, country, and even among countries and continents has been identified by molecular techniques. We sought to determine whether clonal spread of MRSA has occurred in Trinidad and Tobago from all MRSA isolates collected between 2000 and 2001. Methods: Clinical isolates of MRSA from three major hospitals in Trinidad and Tobago were identified by standard laboratory methods and analyzed using multiplex polymerase chain reaction (PCR) and pulsed-field gel electrophoresis (PFGE) after SmaI digestion. Results: There was a 12.8% prevalence of MRSA in three major regional hospitals in Trinidad and Tobago. All 60 randomly selected MRSA strains from these hospitals produced similar PFGE banding patterns, suggesting a genetic relatedness among strains and that they belonged to a single clonal family. All isolates were negative for the Panton-Valentine leukocidin gene (pvl). These strains shared a PFGE banding pattern approximately (96%) the same as a Canadian strain called CMRSA-6 in the Canadian National Microbiology Laboratory database. Conclusions: We conclude that only one major PFGE genotype of MRSA clone is circulating among the three major regional hospitals in Trinidad and Tobago suggesting one of three possible scenarios of microevolution: (1) all were from the dissemination of a single epidemic MRSA clone prevailing in these hospitals in Trinidad and Tobago; or (2) MRSA in Trinidad and Tobago is evolving § This study was presented in part at the 12th International Congress of the
PLOS ONE, Feb 19, 2014
It has been shown previously that high rates of methicillin-and mupirocin-resistant Staphylococcu... more It has been shown previously that high rates of methicillin-and mupirocin-resistant Staphylococcus aureus exist in the Caribbean islands of Trinidad and Tobago, as well as a high prevalence of Panton-Valentine leukocidin-positive S. aureus. Beyond these studies, limited typing data have been published. In order to obtain insight into the population structure not only of MRSA but also of methicillin-susceptible S. aureus, 294 clinical isolates collected in 2012/2013 were typed by microarray hybridisation. A total of 15.31% of the tested isolates were MRSA and 50.00% were PVL-positive. The most common MSSA strains were PVL-positive CC8-MSSA (20.41% of all isolates tested), PVL-positive CC152-MSSA (9.52%) and PVL-positive CC30-MSSA (8.84%) while the most common MRSA were ST239-MRSA-III&SCCmer (9.18%) and ST8-MRSA-IV, ''USA300'' (5.78%). 2.38% of characterised isolates belonged to distinct strains likely to be related to ''Staphylococcus argenteus'' lineages. The population structure of S. aureus isolates suggests an importation of strains from Africa, endemicity of PVL-positive MSSA (mainly CC8) and of ST239-MRSA-III, and a recent emergence of the PVL-positive CC8-MRSA-IV strain ''USA300''.
InTech eBooks, Apr 4, 2012
In this paper, the main objective was to raise chickens' antibodies against three crucial public ... more In this paper, the main objective was to raise chickens' antibodies against three crucial public health microorganisms: the human immunodeficiency virus-1, Salmonella spp, and Staphylococcus aureus. Immunogens were prepared from the said microorganisms. Chickens were vaccinated either orally or intramuscularly. After a booster immunization, mostly eggs were collected and assess for the presence of specific antibodies. The most important results were the production of a large amount of anti-HIV antibodies in chicken's eggs, and also the synthesis of anti-protein A antibodies with the ability to inhibit the growth of S. aureus in vitro and to serve as anti-anti-idiotypic antibodies with the capacity of neutralizing the original antigen. Enzymelinked immune absorbent assays detected the presence of these antibodies as anti-Salmonella antibodies that were critical in reducing the bacterial load in the stomach and caeca compared with a control group. The vaccines were effective and safe, but more laboratory work, and economics have to be carried out to start a human trial.
British microbiology research journal, Jan 10, 2015
Journal of Medical Case Reports, Apr 20, 2011
Introduction: Certain Staphylococcus aureus strains produce Panton-Valentine leukocidin, a toxin ... more Introduction: Certain Staphylococcus aureus strains produce Panton-Valentine leukocidin, a toxin that lyses white blood cells causing extensive tissue necrosis and chronic, recurrent or severe infection. This report documents a confirmed case of methicillin-sensitive Staphylococcus aureus strain harboring Panton-Valentine leukocidin genes from Trinidad and Tobago. To the best of our knowledge, this is the first time that such a case has been identified and reported from this country. Case presentation: A 13-year-old Trinidadian boy of African descent presented with upper respiratory symptoms and gastroenteritis-like syptoms. About two weeks later he was re-admitted to our hospital complaining of pain and weakness affecting his left leg, where he had received an intramuscular injection of an anti-emetic drug. He deteriorated and developed septic arthritis, necrotizing fasciitis and septic shock with acute respiratory distress syndrome, leading to death within 48 hours of admission despite intensive care treatment. The infection was caused by S. aureus. Bacterial isolates from specimens recovered from our patient before and after his death were analyzed using microarray DNA analysis and spa typing, and the results revealed that the S. aureus isolates belonged to clonal complex 8, were methicillin-susceptible and positive for Panton-Valentine leukocidin. An autopsy revealed multi-organ failure and histological tissue stains of several organs were also performed and showed involvement of his lungs, liver, kidneys and thymus, which showed Hassal's corpuscles. Conclusion: Rapid identification of Panton-Valentine leukocidin in methicillin-sensitive S. aureus isolates causing severe infections is necessary so as not to miss their potentially devastating consequences. Early feedback from the clinical laboratories is crucial.
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Papers by Patrick Eberechi Akpaka