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MSc (Biology), North-West University, Mafikeng Campus Salmonella species are currently one of the most widespread foodborne pathogens that claim millions of lives yearly nationwide and therefore they pose severe challenges in humans in developing as well as developed countries. In addition, Salmonella infections are difficult to treat due to the ·emergence and wide spread distribution of antibiotic resistant strains. Treatment failures amplify the need to explore the virulence capabilities of other antibacterial agents such as bacteriophages to serve as alternative antimicrobial agents, especially in resolving the war against resistant bacteria strains. The aim of this study was to isolate, characterise and determine the virulence capabilities of Salmonella species and Salmonella specific bacteriophages from cattle faeces and raw beef obtained from some supermarkets and butcheries in the North West Province, South Africa against environmental antibiotic resistant isolates. A total of 300 presumptive Salmonella isolates were isolated from 160 samples (cattle faeces and raw beef) using Salmonella Shigella agar. Typical pale yellow colonies with black spots on their centres were subjected to both preliminary and confirmatory tests specific for Salmonella species. The antibiotic resistance profiles of the Salmonella strains were determined against a panel of 12 antimicrobial agents. Multiple antibiotic resistance phenotypes and cluster analysis of antibiotic resistance inhibition zone diameter data was used to determine the phenotypic relationship of isolates from different sources. PCR assays were used to determine the pathogenicity of the isolates in order to assess their impact on consumers. Genetic similarities among isolates from different sampling stations and/or sources were assessed by determining the restriction fragment length polymorphic (RFLP) patterns of the 16S rRNA gene fragments amplified from isolates in the study. Furthermore, morphological characterisation of Salmonella specific bacteriophages was achieved using the double agar layer technique and electron microscopy. The findings of the study suggest a high presence 140 (46%) of Salmonella species in both cattle faeces and raw beef obtained from the different locations. All the isolates were Gram negative rods while a significantly large proportion 291 (97%) were oxidase negative and only 12 (4%) of the isolates produced H2S. Eight (34.8%) representative isolates were identified as Salmonella species. Of the 300 presumptive isolates a large proportion 159 (53%) were positive for Salmonella based on agglutination with the polyvalent O antiserum and belonged to groups A-G, while 185 (61.7%) were positive for the polyvalent H antiserum. Salmonella species specific 16S rRNA PCR analysis indicated that 128 (42 .7%) were positively identified. Despite the fact that only a small proportion 60 (20%) of the isolates were confirmed as Salmonella species based on the presence of the f/iC gene sequence while 80 (26.7%) had the f/iB gene fragment. Large proportions (62.4% to 94.3%) of the isolates from both cattle faeces and beef samples were most often resistant to Erythromycin, Rifampicin, Penicillin, Ampicillin and Cephalexin. On the contrary, these isolates showed very little resistance (4.3% to 37.9%) against Cefixime, Nalidixic Acid, Gentamicin, Ciprofloxacin, Tetracycline, Norfloxacin and Chloramphenicol. MAR phenotypes E-RP-PG-CFXM, AP-E-RP-PGV CFXM, RP-PG-CFXM, AP-CFM-E-RP-PG-CFXM, T-E-RP-PG-CFXM and AP-CFM-T-ERP- PG-CFXM were dominant among these isolates. On the other hand, phenotypes AP-CFM-NA-CIP-NOR-E-RP-PG, E-RP-PG-CFXM and T-E-RP-PG-CFXM were predominant among isolates obtained from Rustenburg. Despite the fact that phenotype AP-CFM-T-E-RP-PG-CFXM was observed only in 1 isolate obtained from Mafikeng, a cause for concern is that this isolate was resistant to 7 of the 12 antibiotics tested. In addition the AP-CFM-NA-CIP-NOR-E-RP-PG was not only dominant among isolates from Rustenburg but the isolates were resistant to eight different antimicrobial agents. Two major clusters (cluster 1 and cluster 2) that contained four sub-clusters (1A, 1 B, 2A and 2B) were obtained. Generally three sub-clusters (1A, 1 B and 2A) were mixed since they had isolates from almost all the different sites sampled. Large proportions 38 (27.1%) and 46 (30.7%) were positive for the spvC and invA virulence genes respectively. RFLP patterns of 16S rRNA gene fragments indicated that the band sizes ranged from 50 bp and 572 bp and from 50 bp to 300 bp for EcoRI and Haelll respectively. The great similarities in the antibiotic resistance profiles of Salmonella isolates from the different locations indicated that isolates share similarly antibiotic exposure histories. In addition, the similarities in the RFLP patterns of 16S rRNA gene fragments also revealed that the data may be of great epidemiological importance and therefore be very useful in identifying the source of contamination. Masters

Background Between 1995 and 2000, KwaZulu–Natal province, South Africa, experienced a marked increase in Plasmodium falciparum malaria, fuelled by pyrethroid and sulfadoxine-pyrimethamine resistance. In response, vector control was strengthened and artemether-lumefantrine (AL) was deployed in the first Ministry of Health artemisinin-based combination treatment policy in Africa. In South Africa, effective vector and parasite control had historically ensured low-intensity malaria transmission. Malaria is diagnosed definitively and treatment is provided free of charge in reasonably accessible public-sector health-care facilities. Methods and Findings We reviewed four years of malaria morbidity and mortality data at four sentinel health-care facilities within KwaZulu–Natal's malaria-endemic area. In the year following improved vector control and implementation of AL treatment, malaria-related admissions and deaths both declined by 89%, and outpatient visits decreased by 85% at the sentinel facilities. By 2003, malaria-related outpatient cases and admissions had fallen by 99%, and malaria-related deaths had decreased by 97%. There was a concomitant marked and sustained decline in notified malaria throughout the province. No serious adverse events were associated causally with AL treatment in an active sentinel pharmacovigilance survey. In a prospective study with 42 d follow up, AL cured 97/98 (99%) and prevented gametocyte developing in all patients. Consistent with the findings of focus group discussions, a household survey found self-reported adherence to the six-dose AL regimen was 96%. Conclusion Together with concurrent strengthening of vector control measures, the antimalarial treatment policy change to AL in KwaZulu–Natal contributed to a marked and sustained decrease in malaria cases, admissions, and deaths, by greatly improving clinical and parasitological cure rates and reducing gametocyte carriage., In KwaZulu-Natal strengthening of vector control and a change in antimalarial treatment policy to use of artemether-lumefantrine has been associated with a decrease in malaria cases, admissions, and deaths.

Tuberculosis remains an important clinical and public health issue in South Africa, which has one of the highest tuberculosis burdens in the world. We aimed to estimate the burden of bacteriologically confirmed pulmonary tuberculosis among people aged 15 years or older in South Africa.This multistage, cluster-based, cross-sectional survey included eligible residents (age ≥15 years, who had slept in a house for ≥10 nights in the preceding 2 weeks) in 110 clusters nationally (cluster size of 500 people; selected by probability proportional-to-population size sampling). Participants completed face-to-face symptom questionnaires (for cough, weight loss, fever, and night sweats) and manually read digital chest X-ray screening. Screening was recorded as positive if participants had at least one symptom or an abnormal chest X-ray suggestive of tuberculosis, or a combination thereof. Sputum samples from participants who were screen-positive were tested by the Xpert MTB/RIF Ultra assay (first sample) and Mycobacteria Growth Indicator Tube culture (second sample), with optional HIV testing. Participants with a positive Mycobacterium tuberculosis complex culture were considered positive for bacteriologically confirmed pulmonary tuberculosis; when culture was not positive, participants with a positive Xpert MTB/RIF Ultra result with an abnormal chest X-ray suggestive of active tuberculosis and without current or previous tuberculosis were considered positive for bacteriologically confirmed pulmonary tuberculosis.Between Aug 15, 2017, and July 28, 2019, 68 771 people were enumerated from 110 clusters, with 53 250 eligible to participate in the survey, of whom 35 191 (66·1%) participated. 9066 (25·8%) of 35 191 participants were screen-positive and 234 (0·7%) were identified as having bacteriologically confirmed pulmonary tuberculosis. Overall, the estimated prevalence of bacteriologically confirmed pulmonary tuberculosis was 852 cases (95% CI 679-1026) per 100 000 population; the prevalence was highest in people aged 35-44 years (1107 cases [95% CI 703-1511] per 100 000 population) and those aged 65 years or older (1104 cases [680-1528] per 100 000 population). The estimated prevalence was approximately 1·6 times higher in men than in women (1094 cases [95% CI 835-1352] per 100 000 population vs 675 cases [494-855] per 100 000 population). 135 (57·7%) of 234 participants with tuberculosis screened positive by chest X-ray only, 16 (6·8%) by symptoms only, and 82 (35·9%) by both. 55 (28·8%) of 191 participants with tuberculosis with known HIV status were HIV-positive.Pulmonary tuberculosis prevalence in this survey was high, especially in men. Despite the ongoing burden of HIV, many participants with tuberculosis in this survey did not have HIV. As more than half of the participants with tuberculosis had an abnormal chest X-ray without symptoms, prioritising chest X-ray screening could substantially increase case finding.Global Fund, BillMelinda Gates Foundation, USAID.