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Item ABBV744 as a potential inhibitor of SARSCoV2 main protease enzyme against COVID19Zeynab Fakhar; Shama Khan; Afrah Alkhuriji; Suliman Y. AlOmar; Aijaz AhmadItem HIV1 resupression on a firstline regimen despite the prescence of phenotypic drug resistanceAdriaan Basson; Salome Charalambous; Christopher Hoffmann; Lynn MorrisItem The Novel Coronavirus and Haemostatic Abnormalities Pathophysiology Clinical Manifesttations and Treatment RecommendationsSusan Louw; Barry Jacobson; Elizabeth Mayne; Tracey WiggillItem Overview of the Haematological Effects of COVID19 InfectionTracey Wiggill; Elizabeth Mayne; Jenifer Vaughan; Susan LouwItem Determining immunological correlates of protection against group B streptococcus colonization in pregnant women(2016) Kwatra, GauravIntroduction: Maternal recto-vaginal colonization with Group B Streptococcus (GBS) is the major risk factor for invasive GBS disease in newborn’s. Maternal vaccination against GBS during pregnancy may prevent or reduce subsequent recto-vaginal colonization in women, which could lower fetal/newborn exposure to GBS and contribute to reducing GBS associated infections during early infancy. In this study we determined the immunological correlates of protection against GBS colonization in black African pregnant women. Methods: We compared GBS serotype-specific serum IgG, mucosal IgG, mucosal IgA and cellular immune responses in relation to GBS rectovaginal acquisition and clearance in pregnant women from 20 to 37+ weeks of gestational age. Furthermore, we also evaluated different media for isolation of GBS from vaginal and rectal swabs. Results: The prevalence of recto-vaginal GBS colonization was 33.0%, 32.7%, 28.7% and 28.4% at 20-25 weeks, 26-30 weeks, 31-35 weeks and 37+ weeks of gestational age, respectively. The most common identified serotypes were Ia (39.2%), III (32.8%) and V (12.4%). The cumulative overall recto-vaginal acquisition rate of new serotypes during the study was 27.9%, including 11.2%, 8.2% and 4.3% for serotypes Ia, III and V, respectively. The recovery of GBS from rectal swabs was significantly higher from direct plating on chromogenic medium (p<0.0001) than from selective broth method. New-acquisition of GBS was inversely correlated with serotype-specific serum IgG concentration for serotype III (p=0.009) and OPA titer for serotype Ia and III (p<0.001 for both) at time of enrolment. Serum IgG concentration significantly associated with protection against recto-vaginal acquisition of the homotypic serotype was ≥1 μg/ml for serotype V (p=0.039), ≥3 μg/ml for serotype Ia (p=0.043) and III (p=0.023). Mucosal IgG correlated significantly with serum IgG with Rho values of 0.839, 0.621 and 0.426 (all p<0.001) for serotype Ia, III and V, respectively. The clearance of serotype-specific GBS recto-vaginal colonization during pregnancy was positively associated with presence of homotypic capsular ELISpot IFN-γ positivity for serotype III (p=0.008) Conclusion: Maternal GBS colonization could be used as end point to evaluate efficacy of GBS vaccine. A serotype-specific capsular polysaccharide based GBS vaccine able to elicit both humoral and cell-mediated capsular immune responses could confer protection against EOD by reducing the exposure of the newborn’s to GBS colonization during the peri-partum period.Item Blood pressure measurements in the ankle are not equivalent to blood pressure measurements in the arm(2014-12) Goldstein, L.N.; Wells, M.; Sliwa, K.Item National sentinel site surveillance for antimicrobial resistance in Klebsiella pneumoniae isolates in South Africa, 2010-2012(2014-08) Perovic, O; Singh- Moodley, A; Duse, A; et al.Background: The increasing rates of antimicrobial resistance observed in the nosocomial pathogen Klebsiella pneumoniae are of major public health concern worldwide. Objectives: To describe the antibiotic susceptibility profiles of K. pneumoniae isolates from bacteraemic patients submitted by sentinel laboratories in five regions of South Africa from mid-2010 to mid-2012. Molecular methods were used to detect the most commonly found extended-spectrum beta-lactamase (ESBL) and carbapenemase resistance genes. Methods: Thirteen academic centres serving the public healthcare sector in Gauteng, KwaZulu-Natal, Free State, Limpopo and Western Cape provinces submitted K. pneumoniae isolates from patients with bloodstream infections. Vitek 2 and MicroScan instruments were used for organism identification and susceptibility testing. Multiplex polymerase chain reactions (PCRs) were used to detect blaCTX-M, blaSHV and blaTEM genes in a proportion of the ESBL isolates. All isolates exhibiting reduced susceptibility to carbapenems were PCR tested for blaKPC and blaNDM-1 resistance genes. Results: Overall, 68.3% of the 2 774 isolates were ESBL-positive, showing resistance to cefotaxime, ceftazidime and cefepime. Furthermore, 46.5% of all isolates were resistant to ciprofloxacin and 33.1% to piperacillin-tazobactam. The major ESBL genes were abundantly present in the sample analysed. Most isolates (95.5%) were susceptible to the carbapenems tested, and no isolates were positive for blaKPC or blaNDM-1. There was a trend towards a decrease in susceptibility to most antibiotics. Conclusion: The high proportion of ESBL-producing K. pneumoniae isolates observed, and the prevalence of ESBL genes, are of great concern. Our findings represent a baseline for further surveillance in SA, and can be used for policy and treatment decisions.Item Laboratory information system data demonstrate successful implementation of the prevention of the mother- child transmission programme in South Africa(2014-03) Sherman, G.G; Lilian, R.R; Bhardwaj, S; et alBackground: Monitoring the prevention of mother-to-child transmission (PMTCT) programme to identify gaps for early intervention is essential as South Africa progresses from prevention to elimination of HIV infection in children. Early infant diagnosis (EID) by an HIV polymerase chain reaction (PCR) test is recommended at 6 weeks of age for all HIV-exposed infants. The National Health Laboratory Service (NHLS) performs the PCR tests for the public health sector and stores test data in a corporate data warehouse (CDW). Objectives: To demonstrate the utility of laboratory data for monitoring trends in EID coverage and early vertical transmission rates and to describe the scale-up of the EID component of the PMTCT programme. Methods. HIV PCR test data from 2003 to 2012 inclusive were extracted from the NHLS CDW by year, province, age of infant tested and test result and used to calculate EID coverage and early vertical transmission rates to provincial level. Results: Rapid scale-up of EID over the first decade of the PMTCT programme was evident from the 100-fold increase in PCR tests to 350 000 by 2012. In 2012, 73% of the estimated 270 000 HIV-exposed infants requiring an early PCR were tested and the early vertical transmission rate had fallen to 2.4% as a result of successful implementation of the PMTCT programme. Conclusions: Laboratory data can provide real time, affordable monitoring of aspects of the PMTCT programme and assist in achieving virtual elimination of paediatric HIV infection in South Africa.Item Critical value reporting : A survey of 36 clinical laboratories in South Africa(2014-01) Schapkaitz, E; Mafika, ZObjective: Critical value policies are used by clinical laboratories to decide when to notify caregivers of life-threatening results. Despite their widespread use, critical value policies have not been published locally. A survey was designed to determine critical value policies for haematology tests in South Africa. Methods: A survey was carried out on 136 identified laboratories across South Africa in January 2013. Of these, 36 responded. Data collected included critical value policies, critical values for haematology parameters, and critical value reporting. Results: Of the 36 laboratories surveyed, 11.1% (n=4) were private, 33.3% (n=12) were affiliated to academic institutions and 55.6% (n=20) were peripheral or regional National Health Laboratory Service laboratories. All the laboratories confirmed that they had a critical value policy, and 83.3% of such policies were derived from local clinical opinion. Mean low and high critical limits for the most frequently listed tests were as follows: haemoglobin <6 and >20 g/dl, platelet count <41 and >1 000 ×109 /l, white cell count <2 and >46×109 /l, activated partial thromboplastin time >101 seconds, and international normalised ratio >6. In almost all cases critical value reporting was performed by the technologist on duty (97.2%). The majority of laboratories required that the person notified of the critical value be the doctor who ordered the test or the caregiver directly involved in the patient’s care (83.3%); 73.3% of laboratories indicated that they followed an algorithm if the doctor/caregiver could not be reached. Conclusion: Each laboratory is responsible for establishing clinically relevant critical limits. Clinicians should be involved in developing the laboratory’s critical value policy. The findings of this survey may be of value to local laboratories that are in the process of establishing or reviewing critical value policies