Characterization of Panton-Valentine leukocidin-positive Staphylococcus aureus from skin and soft tissue infections and wounds in Nigeria: a cross-sectional study.

Background:Staphylococcus aureus is a significant pathogen implicated in numerous nosocomial and community-acquired infections. The Panton-Valentine leukocidin (PVL) can be associated with severe necrotizing diseases such as pneumonia, skin and soft tissue infection (SSTI).  Methods: In total, 96 S. aureus isolates were obtained from patients presenting with wounds (n=48) and soft tissue infections (SSTIs, n=48). These were characterized based on their antimicrobial susceptibility profile, the possession of virulence genes (e.g. capsular type, PVL), accessory gene regulator ( agr) type, and the staphylococcal protein A ( spa) type. The production of the PVL protein was assessed by western blotting. Results: All isolates were susceptible to methicillin. The resistance was highest to penicillin (97.9%), followed by trimethoprim/sulfamethoxazole (85.4%) and tetracycline (10.4%). The PVL gene was found in 83.3% of isolates from SSTIs and in 79.2% of isolates from wound. Of these, 53 (68%) produced PVL as assessed by western blotting. The most prevalent spa type was the t084 (78.1%, n=75) and, majority of the isolates carried  agr2 (82.3%, n=79). Conclusions: Prevalence of antibiotic resistant PVL-positive methicillin susceptible S. aureus strains has severe implications on PVL mediated infections.

Data set on Rapid Diagnostic Tests (RDTs) and microscopy for diagnosing plasmodium falciparum and plasmodium vivax.

The World Heal Organization (WHO) has identified malaria diagnosis as being pivotal to eradicating the disease by 2030 as stipulated in the Sustainable Development Goals (SDG). The data presented here was obtained from outpatients of a hospital in the South Western Region of Nigeria from November 2016 to May 2017. The data contains malaria incidence amongst asymptomatic and symptomatic outpatients in the period under review. Malaria incidence was obtained using two diagnostic test kits, Bioline SD (HRP-2) and ACON (HRP-2/Aldolase) alongside Microscopy as gold standard. Specificity, Sensitivity and Kappa statistic of each test device is presented in the tables herewith. Data presented here could be used alongside other data sources to assess the state of malaria diagnostics.

Molecular Characterization and Antimicrobial Susceptibility of Staphylococcus aureus Isolates from Clinical Infection and Asymptomatic Carriers in Southwest Nigeria.

Few reports from Africa suggest that resistance pattern, virulence factors and genotypes differ between Staphylococcus aureus from nasal carriage and clinical infection. We therefore compared antimicrobial resistance, selected virulence factors and genotypes of S. aureus from nasal carriage and clinical infection in Southwest Nigeria. Non-duplicate S. aureus isolates were obtained from infection (n = 217) and asymptomatic carriers (n = 73) during a cross sectional study in Lagos and Ogun States, Nigeria from 2010-2011. Susceptibility testing was performed using Vitek automated systems. Selected virulence factors were detected by PCR. The population structure was assessed using spa typing. The spa clonal complexes (spa-CC) were deduced using the Based Upon Repeat Pattern algorithm (BURP). Resistance was higher for aminoglycosides in clinical isolates while resistances to quinolones and tetracycline were more prevalent in carrier isolates. The Panton-Valentine leukocidin (PVL) was more frequently detected in isolates from infection compared to carriage (80.2 vs 53.4%; p<0.001, chi2-test). Seven methicillin resistant S. aureus isolates were associated with spa types t002, t008, t064, t194, t8439, t8440 and t8441. The predominant spa types among the methicillin-susceptible S. aureus isolates were t084 (65.5%), t2304 (4.4%) and t8435 (4.1%). spa-CC 084 was predominant among isolates from infection (80.3%, n = 167) and was significantly associated with PVL (OR = 7.1, 95%CI: 3.9-13.2, p<0.001, chi2-test). In conclusion, PVL positive isolates were more frequently detected among isolates from infection compared to carriage and are associated with spa-CC 084.

In vitro studies on the sensitivity pattern of Plasmodium falciparum to anti-malarial drugs and local herbal extracts.

BACKGROUND: The resistance of human malaria parasites to anti-malarial compounds has become considerable concern, particularly in view of the shortage of novel classes of anti-malarial drugs. One way to prevent resistance is by using new compounds that are not based on existing synthetic antimicrobial agents. RESULTS: Sensitivity of 100 Plasmodium falciparum isolates to chloroquine, quinine, amodiaquine, mefloquine, sulphadoxine/pyrimethamine, artemisinin, Momordica charantia ('Ejirin') Diospyros monbuttensis ('Egun eja') and Morinda lucida ('Oruwo') was determined using the in vitro microtest (Mark III) technique to determine the IC50 of the drugs. All the isolates tested were sensitive to quinine, mefloquine and artesunate. Fifty-one percent of the isolates were resistant to chloroquine, 13% to amodiaquine and 5% to sulphadoxine/pyrimethamine. Highest resistance to chloroquine (68.9%) was recorded among isolates from Yewa zone while highest resistance to amodiaquine (30%) was observed in Ijebu zone. Highest resistance to sulphadoxine/pyrimethamine was recorded in Yewa and Egba zones, respectively. A positive correlation was observed between the responses to artemisinin and mefloquine (P<0.05), artemisinin and quinine (P<0.05) and quinine and mefloquine (P<0.05). A negative correlation was observed between the responses to chloroquine and mefloquine (P>0.05). Highest anti-plasmodial activity was obtained with the ethanolic extract of D. monbuttensis (IC50 = 3.2 nM) while the lowest was obtained from M. lucida (IC50 = 25 nM). CONCLUSIONS: Natural products isolated from plants used in traditional medicine, which have potent anti-plasmodial action in vitro, represent potential sources of new anti-malarial drugs.