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1.
Cell ; 184(9): 2348-2361.e6, 2021 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-33730597

RESUMO

The race to produce vaccines against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) began when the first sequence was published, and this forms the basis for vaccines currently deployed globally. Independent lineages of SARS-CoV-2 have recently been reported: UK, B.1.1.7; South Africa, B.1.351; and Brazil, P.1. These variants have multiple changes in the immunodominant spike protein that facilitates viral cell entry via the angiotensin-converting enzyme-2 (ACE2) receptor. Mutations in the receptor recognition site on the spike are of great concern for their potential for immune escape. Here, we describe a structure-function analysis of B.1.351 using a large cohort of convalescent and vaccinee serum samples. The receptor-binding domain mutations provide tighter ACE2 binding and widespread escape from monoclonal antibody neutralization largely driven by E484K, although K417N and N501Y act together against some important antibody classes. In a number of cases, it would appear that convalescent and some vaccine serum offers limited protection against this variant.


Assuntos
Vacinas contra COVID-19/sangue , Vacinas contra COVID-19/imunologia , SARS-CoV-2/imunologia , Animais , Anticorpos Monoclonais/imunologia , COVID-19/imunologia , COVID-19/terapia , COVID-19/virologia , Chlorocebus aethiops , Ensaios Clínicos como Assunto , Células HEK293 , Humanos , Imunização Passiva , Modelos Moleculares , Mutação/genética , Testes de Neutralização , Ligação Proteica , SARS-CoV-2/química , SARS-CoV-2/genética , Células Vero , Soroterapia para COVID-19
2.
Emerg Infect Dis ; 30(1): 163-167, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38063078

RESUMO

We detected a novel GII.4 variant with an amino acid insertion at the start of epitope A in viral protein 1 of noroviruses from the United States, Gabon, South Africa, and the United Kingdom collected during 2017-2022. Early identification of GII.4 variants is crucial for assessing pandemic potential and informing vaccine development.


Assuntos
Infecções por Caliciviridae , Gastroenterite , Norovirus , Humanos , Gastroenterite/epidemiologia , Norovirus/genética , Infecções por Caliciviridae/epidemiologia , Genótipo , Pandemias , Filogenia
3.
Emerg Infect Dis ; 30(4): 766-769, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38526207

RESUMO

We describe a classic case of nasal rhinosporidiosis in a woman who resided in Johannesburg, South Africa, but originated from a rural area in Eastern Cape Province. We confirmed histologic diagnosis using PCR testing and compared details with those from records on 17 other cases from South Africa.


Assuntos
Rinosporidiose , Feminino , Humanos , África do Sul/epidemiologia , Rinosporidiose/diagnóstico , Nariz
4.
Int J Cancer ; 154(2): 273-283, 2024 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-37658695

RESUMO

HIV infection increases the risk of developing cervical cancer; however, longitudinal studies in sub-Saharan Africa comparing cervical cancer rates between women living with HIV (WLWH) and women without HIV are scarce. To address this gap, we compared cervical precancer and cancer incidence rates between WLWH and women without HIV in South Africa using reimbursement claims data from a medical insurance scheme from January 2011 to June 2020. We used Royston-Parmar flexible parametric survival models to estimate cervical precancer and cancer incidence rates as a continuous function of age, stratified by HIV status. Our study population consisted of 518 048 women, with exclusions based on the endpoint of interest. To analyse cervical cancer incidence, we included 517 312 women, of whom 564 developed cervical cancer. WLWH had an ~3-fold higher risk of developing cervical precancer and cancer than women without HIV (adjusted hazard ratio for cervical cancer: 2.99; 95% confidence interval [CI]: 2.40-3.73). For all endpoints of interest, the estimated incidence rates were higher in WLWH than women without HIV. Cervical cancer rates among WLWH increased at early ages and peaked at 49 years (122/100 000 person-years; 95% CI: 100-147), whereas, in women without HIV, incidence rates peaked at 56 years (40/100 000 person-years; 95% CI: 36-45). Cervical precancer rates peaked in women in their 30s. Analyses of age-specific cervical cancer rates by HIV status are essential to inform the design of targeted cervical cancer prevention policies in Southern Africa and other regions with a double burden of HIV and cervical cancer.


Assuntos
Infecções por HIV , Infecções por Papillomavirus , Displasia do Colo do Útero , Neoplasias do Colo do Útero , Humanos , Feminino , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Neoplasias do Colo do Útero/epidemiologia , Neoplasias do Colo do Útero/prevenção & controle , Incidência , África do Sul/epidemiologia , Displasia do Colo do Útero/epidemiologia , Infecções por Papillomavirus/epidemiologia
5.
Immunol Cell Biol ; 102(1): 15-20, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37524375

RESUMO

In the vast and diverse continent of Africa, the field of immunology holds immense significance as it navigates the complex landscape of infectious diseases and public health challenges. In this article, we speak with Professor Clive Gray, who provides powerful and valuable insights into the unique research opportunities and immunological advancements supported by Africa's unique blend of social, economic and environmental factors and also discusses the societal and cultural challenges that need to be overcome for equitable research to be achieved across the continent.


Assuntos
Alergia e Imunologia , Fortalecimento Institucional , África do Sul
6.
J Clin Microbiol ; 62(4): e0164923, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38470024

RESUMO

Scaling up of newer innovations that address the limitations of the dried blood spot and the logistics of plasma monitoring is needed. We employed a multi-site, cross-sectional assessment of the plasma separation card (PSC) on blood specimens collected from all consenting adults, assenting young and pediatric patients living with HIV from 10 primary healthcare clinics in South Africa. Venous blood for EDTA-plasma samples was collected and analyzed according to the standard of care assay, while collected capillary blood for the PSC samples was analyzed using the Roche COBAS AmpliPrep/Cobas TaqMan (CAP/CTM) HIV-1 Test at the National Reference laboratories. McNemar tests assessed the differences in concordance between the centrifuged plasma and dried plasma spots. The usability of PSC by blood spotting, PSC preparation, and pre-analytical work was assessed by collecting seven-point Likert-scale data from healthcare and laboratory workers. We enrolled 538 patients, mostly adults [n = 515, 95.7% (95% CI: 93.7%-97.1%)] and females [n = 322, 64.2% (95% CI: 60.0%-68.1%)]. Overall, 536 paired samples were collected using both PSC- and EDTA-plasma diagnostics, and 502 paired PSC- and EDTA-plasma samples assessed. Concordance between the paired samples was obtained for 446 samples. Analysis of these 446 paired samples at 1,000 copies per milliliter threshold yielded an overall sensitivity of 87.5% [95% CI: 73.2%-95.8%] and specificity of 99.3% [95% CI: 97.9%-99.8%]. Laboratory staff reported technical difficulties in most tasks. The usability of the PSC by healthcare workers was favorable. For policymakers to consider PSC scale-up for viral load monitoring, technical challenges around using PSC at the clinic and laboratory level need to be addressed. IMPORTANCE: Findings from this manuscript emphasize the reliability of the plasma separation card (PSC), a novel diagnostic method that can be implemented in healthcare facilities in resource-constrained settings. The agreement of the PSC with the standard of care EDTA plasma for viral load monitoring is high. Since the findings showed that these tests were highly specific, we recommend a scale-up of PSC in South Africa for diagnosis of treatment failure.


Assuntos
Infecções por HIV , HIV-1 , Adulto , Feminino , Humanos , Criança , Sensibilidade e Especificidade , HIV-1/genética , Carga Viral/métodos , África do Sul , Estudos Transversais , Ácido Edético , Reprodutibilidade dos Testes , RNA Viral
7.
Appl Environ Microbiol ; 90(8): e0084224, 2024 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-39058027

RESUMO

Bartonella spp. are intracellular bacteria associated with several re-emerging human diseases. Small mammals play a significant role in the maintenance and spread of Bartonella spp. Despite the high small mammal biodiversity in South Africa, there is limited epidemiological information regarding Bartonella spp. in these mammals. The main aim of this study was to determine the prevalence and genetic diversity of Bartonella spp. from wild small mammals from 15 localities in 8 provinces of South Africa. Small mammals (n = 183) were trapped in the Eastern Cape, Free State, Gauteng, Limpopo, Mpumalanga, Northern Cape, North West, and Western Cape provinces of South Africa between 2010 and 2018. Heart, kidney, liver, lung, and spleen were harvested for Bartonella DNA screening, and prevalence was determined based on the PCR amplification of partial fragments of the 16S-23S rRNA intergenic spacer (ITS) region, gltA, and rpoB genes. Bartonella DNA was detected in Aethomys chrysophilus, Aethomys ineptus, Gerbillurus spp., Lemniscomys rosalia, Mastomys coucha, Micaelamys namaquensis, Rhabdomys pumilio, and Thallomys paedulcus. An overall prevalence of 16.9% (31/183, 95% CI: 12.2%-23%) was observed. Bartonella elizabethae, Bartonella grahamii, and Bartonella tribocorum were the zoonotic species identified, while the remaining sequences were aligned to uncultured Bartonella spp. with unknown zoonotic potential. Phylogenetic analyses confirmed five distinct Bartonella lineages (I-V), with lineage IV displaying strong M. coucha host specificity. Our results confirm that South African wild small mammals are natural reservoirs of a diverse assemblage of Bartonella spp., including some zoonotic species with high genetic diversity, although prevalence was relatively low.IMPORTANCESmall mammals play a significant role in the maintenance and spread of zoonotic pathogens such as Bartonella spp. Despite the high small mammal biodiversity in southern Africa including South Africa, there is limited epidemiological information regarding Bartonella spp. in these mammals across the country. Results from our study showed the liver and spleen had the highest positive cases for Bartonella spp. DNA among the tested organs. Bartonella elizabethae, B. grahamii, and B. tribocorum were the three zoonotic species identified and five distinct Bartonella lineages (I-V) were confirmed through phylogenetic analyses. To the best of our knowledge, this study presents the first extensive nuclear diversity investigation of Bartonella spp. in South African small mammals in South Africa.


Assuntos
Infecções por Bartonella , Bartonella , Variação Genética , Bartonella/genética , Bartonella/isolamento & purificação , Bartonella/classificação , África do Sul/epidemiologia , Animais , Infecções por Bartonella/epidemiologia , Infecções por Bartonella/microbiologia , Infecções por Bartonella/veterinária , Prevalência , Filogenia , Animais Selvagens/microbiologia , DNA Bacteriano/genética
8.
J Med Virol ; 96(3): e29514, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38488486

RESUMO

Enteroviruses cause a wide range of neurological illnesses such as encephalitis, meningitis, and acute flaccid paralysis. Two types of enteroviruses, echovirus E4 and E9, have recently been detected in South Africa and are known to be associated with meningitis and encephalitis. The objective of this study was to characterize enterovirus strains detected in cerebrospinal fluid specimens of hospitalized patients in the private and public sector to identify genotypes associated with meningitis and encephalitis. From January 2019 to June 2021 enterovirus positive nucleic acid samples were obtained from a private (n = 116) and a public sector (n = 101) laboratory. These enteroviruses were typed using a nested set of primers targeting the VP1 region of the enterovirus genome, followed by Sanger sequencing and BLASTn analysis. Forty-two percent (91/217) of the strains could be genotyped. Enterovirus B species was the major species detected in 95% (86/91) of the specimens, followed by species C in 3% (3/91) and species A in 2% (2/91) of the specimens. Echovirus E4 and E9 were the two major types identified in this study and were detected in 70% (64/91) and in 10% (9/91) of specimens, respectively. Echovirus E11 has previously been identified in sewage samples from South Africa, but this study is the first to report Echovirus E11 in cerebrospinal fluid specimens from South African patients. The genotypes identified during this study are known to be associated with encephalitis and meningitis. The predominant detection of echovirus E4 followed by E9 corresponds with other studies conducted in South Africa.


Assuntos
Encefalite , Infecções por Enterovirus , Enterovirus , Meningite , Humanos , Lactente , África do Sul/epidemiologia , Setor Público , Enterovirus/genética , Infecções por Enterovirus/diagnóstico , Enterovirus Humano B/genética , Meningite/epidemiologia , Líquido Cefalorraquidiano , Filogenia
9.
J Hum Evol ; 187: 103480, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38159536

RESUMO

Dispersal patterns in primates have major implications for behavior and sociality but are difficult to reconstruct for fossil species. This study applies novel strontium isotope methodologies that have reliably predicted philopatry and dispersal patterns in chimpanzees and other modern primates to previously published strontium isotope ratios (87Sr/86Sr) of two South African hominins, Australopithecus africanus and Australopithecus robustus. In this study, the difference or 'offset' was calculated between the 87Sr/86Sr of each fossil tooth compared to local bioavailable 87Sr/86Sr as defined by cluster analysis of modern plant isotope ratios. Large teeth (presumably belonging to males) have low offsets from local 87Sr/86Sr proxies, while small teeth (presumably from females) have greater offsets from local 87Sr/86Sr proxies. This supports previous conclusions of male philopatry and female dispersal in both A. africanus and A. robustus. Furthermore, A. robustus shows more extreme differences between presumed males and females compared to A. africanus. This is analogous to differences seen in modern olive baboons compared to chimpanzees and suggests that A. africanus may have had a larger home range than A. robustus. Neither hominin species has 87Sr/86Sr consistent with riparian habitat preferences despite the demonstrated presence of riparian habitats in South Africa at the time.


Assuntos
Hominidae , Anormalidades Dentárias , Masculino , Animais , Feminino , Pan troglodytes , África do Sul , Isótopos de Estrôncio/análise , Ecossistema , Fósseis
10.
Neuroepidemiology ; : 1-10, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38857577

RESUMO

INTRODUCTION: We aimed to investigate mid-life food insecurity over time in relation to subsequent memory function and rate of decline in Agincourt, rural South Africa. METHODS: Data from the longitudinal Agincourt Health and Socio-Demographic Surveillance System (Agincourt HDSS) were linked to the population-representative Health and Aging in Africa: A Longitudinal Study of an INDEPTH Community in South Africa (HAALSI). Food insecurity (yes vs. no) and food insecurity intensity (never/rarely/sometimes vs. often/very often) in the past month were assessed every 3 years from 2004 to 2013 in Agincourt HDSS. Cumulative exposure to each food insecurity measure was operationalized as 0, 1, and ≥2 time points. Episodic memory was assessed from 2014/15 to 2021/22 in HAALSI. Mixed-effects linear regression models were fitted to investigate the associations of each food insecurity measure with memory function and rate of decline over time. RESULTS: A total of 3,186 participants (mean age [SD] in 2004: 53 [12.87]; range: 30-96) were included and 1,173 (36%) participants experienced food insecurity in 2004, while this figure decreased to 490 (15%) in 2007, 489 (15%) in 2010, and 150 (5%) in 2013. Experiencing food insecurity at one time point (vs. never) from 2004 to 2013 was associated with lower baseline memory function (ß = -0.095; 95% CI: -0.159 to -0.032) in 2014/15 but not rate of memory decline. Higher intensity of food insecurity at ≥2 time points (vs. never) was associated with lower baseline memory function (ß = -0.154, 95% CI: -0.338 to 0.028), although the estimate was imprecise. Other frequencies of food insecurity and food insecurity intensity were not associated with memory function or decline in the fully adjusted models. CONCLUSION: In this setting, mid-life food insecurity may be a risk factor for lower later-life memory function, but not decline.

11.
Epilepsia ; 65(1): 165-176, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37964464

RESUMO

OBJECTIVE: Focal epilepsy is common in low- and middle-income countries. The frequency and nature of possible underlying structural brain abnormalities have, however, not been fully assessed. METHODS: We evaluated the possible structural causes of epilepsy in 331 people with epilepsy (240 from Kenya and 91 from South Africa) identified from community surveys of active convulsive epilepsy. Magnetic resonance imaging (MRI) scans were acquired on 1.5-Tesla scanners to determine the frequency and nature of any underlying lesions. We estimated the prevalence of these abnormalities using Bayesian priors (from an earlier pilot study) and observed data (from this study). We used a mixed-effect modified Poisson regression approach with the site as a random effect to determine the clinical features associated with neuropathology. RESULTS: MRI abnormalities were found in 140 of 240 (modeled prevalence = 59%, 95% confidence interval [CI]: 53%-64%) of people with epilepsy in Kenya, and in 62 of 91 (modeled prevalence = 65%, 95% CI: 57%-73%) in South Africa, with a pooled modeled prevalence of 61% (95% CI: 56%-66%). Abnormalities were common in those with a history of adverse perinatal events (15/23 [65%, 95% CI: 43%-84%]), exposure to parasitic infections (83/120 [69%, 95% CI: 60%-77%]) and focal electroencephalographic features (97/142 [68%, 95% CI: 60%-76%]), but less frequent in individuals with generalized electroencephalographic features (44/99 [44%, 95% CI: 34%-55%]). Most abnormalities were potentially epileptogenic (167/202, 82%), of which mesial temporal sclerosis (43%) and gliosis (34%) were the most frequent. Abnormalities were associated with co-occurrence of generalized non-convulsive seizures (relative risk [RR] = 1.12, 95% CI: 1.04-1.25), lack of family history of seizures (RR = 0.91, 0.86-0.96), convulsive status epilepticus (RR = 1.14, 1.08-1.21), frequent seizures (RR = 1.12, 1.04-1.20), and reported use of anti-seizure medication (RR = 1.22, 1.18-1.26). SIGNIFICANCE: MRI identified pathologies are common in people with epilepsy in Kenya and South Africa. Mesial temporal sclerosis, the most common abnormality, may be amenable to surgical correction. MRI may have a diagnostic value in rural Africa, but future longitudinal studies should examine the prognostic role.


Assuntos
Encefalopatias , Epilepsia Generalizada , Epilepsia , Esclerose Hipocampal , Humanos , Quênia/epidemiologia , África do Sul/epidemiologia , Teorema de Bayes , Projetos Piloto , Epilepsia/diagnóstico por imagem , Epilepsia/epidemiologia , Encefalopatias/complicações , Epilepsia Generalizada/complicações , Imageamento por Ressonância Magnética
12.
Genome ; 2024 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-38996389

RESUMO

Combating wildlife crimes in South Africa requires accurate identification of traded species and their products. Diagnostic morphological characteristics needed to identify species are often lost when specimens are processed and customs officials lack the expertise to identify species. As a potential solution, DNA barcoding can be used to identify morphologically indistinguishable specimens in forensic cases. However, barcoding is hindered by the reliance on comprehensive, validated DNA barcode reference databases, which are currently limited. To overcome this limitation, we constructed a barcode library of cytochrome c oxidase subunit 1 and cytochrome b sequences for threatened and protected mammals exploited in southern Africa. Additionally, we included closely related or morphologically similar species and assessed the database's ability to identify species accurately. Published southern African sequences were incorporated to estimate intraspecific and interspecific variation. Neighbor-joining trees successfully discriminated 94%-95% of the taxa. However, some widespread species exhibited high intraspecific distances (>2%), suggesting geographic sub-structuring or cryptic speciation. Lack of reliable published data prevented the unambiguous discrimination of certain species. This study highlights the efficacy of DNA barcoding in species identification, particularly for forensic applications. It also highlights the need for a taxonomic re-evaluation of certain widespread species and challenging genera.

13.
Malar J ; 23(1): 62, 2024 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-38419105

RESUMO

BACKGROUND: Malaria elimination requires closely co-ordinated action between neighbouring countries. In Southern Africa several countries have reduced malaria to low levels, but the goal of elimination has eluded them thus far. The Southern Africa Development Community (SADC) Malaria Elimination Eight (E8) initiative was established in 2009 between Angola, Botswana, Eswatini, Mozambique, Namibia, South Africa, Zambia, and Zimbabwe to coordinate malaria interventions aiming to eliminate malaria by 2030. Cross-border coordination is important in malaria elimination settings as it strengthens surveillance, joint planning and implementation, knowledge exchange and optimal use of resources. This paper describes how this collaboration is realized in practice, its achievements and challenges, and its significance for malaria elimination prospects. METHODS: The ministers of health of the E8 countries oversee an intergovernmental technical committee supported by specialist working groups consisting of technical personnel from member countries and partner institutions. These technical working groups are responsible for malaria elimination initiatives in key focus areas such as surveillance, vector control, diagnosis, case management, behaviour change and applied research. The technical working groups have initiated and guided several collaborative projects which lay essential groundwork for malaria elimination. RESULTS: The E8 collaboration has yielded achievements in the following key areas. (1) Establishment and evaluation of malaria border health posts to improve malaria services in border areas and reduce malaria among resident and, mobile and migrant populations. (2) The development of a regional malaria microscopy slide bank providing materials for diagnostic training and proficiency testing. (3) A facility for regional external competency assessment and training of malaria microscopy trainers in collaboration with the World Health Organization. (4) Entomology fellowships that improved capacity in entomological surveillance; an indoor residual spraying (IRS) training of trainers' scheme to enhance the quality of this core intervention in the region. (5) Capacity development for regional malaria parasite genomic surveillance. (6) A mechanism for early detection of malaria outbreak through near real time reporting and a quarterly bulletins of malaria incidence in border districts. CONCLUSIONS: The E8 technical working groups system embodies inter-country collaboration of malaria control and elimination activities. It facilitates sustained interaction between countries through a regional approach. The groundwork for elimination has been laid, but the challenge will be to maintain funding for collaboration at this level whilst reducing reliance on international donors and to build capacities necessary to prepare for malaria elimination.


Assuntos
Malária , Humanos , Malária/epidemiologia , Malária/prevenção & controle , África Austral/epidemiologia , Surtos de Doenças , Moçambique/epidemiologia , África do Sul/epidemiologia
14.
Artigo em Inglês | MEDLINE | ID: mdl-39259456

RESUMO

PURPOSE: The urinary tract is colonized by microbial communities that impact urinary health. Previous studies have suggested that the bacterial composition of the male urinary microbiota is related to STIs. This study assessed the bacterial composition of the urinary microbiome in South African MSM with and without C. trachomatis. METHODS: This study used urine samples from MSM attending care at the King Edward VIII hospital and the Aurum Institute in Durban, South Africa. A total of 200 samples were tested for C. trachomatis infection using the Applied Biosystems™ TaqMan® Assays. Urinary microbiomes of 23 samples were characterized using 16 S rRNA (V3 and V4) gene sequencing on the Illumina MiSeq platform. RESULTS: Bacterial taxonomic analysis showed a high abundance of Streptococcus, Corynebacterium, and Staphylococcus in all the sequenced samples. Moreover, Prevotella and Lactobacillus were detected in urine samples of MSM. Alpha diversity metrics showed a slight increase in microbial diversity in C. trachomatis positive samples; however, this was not significant (ANOVA, P > 0.05). Principal coordinates analysis (PCoA) showed that the microbiome of C. trachomatis infected MSM was not clearly different from those uninfected. Distinct bacterial communities were not detected between positive and negative samples (PERMANOVA F1,22= 1.0284, R2 = 0.047%, P = 0.385). CONCLUSION: Most microbiome studies on MSM to date have focused on the gut microenvironment. Few studies, however, have provided data regarding the normal composition of the male urethral microbiomes or if these microbiomes are associated with male STIs. This study adds to the growing body of knowledge highlighting the urinary microbiome in MSM.

15.
Eur J Clin Microbiol Infect Dis ; 43(4): 627-640, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38265603

RESUMO

PURPOSE: The emergence of carbapenem-resistant P. aeruginosa (CRPA) harbouring acquired carbapenemase genes (blaVIM, blaIMP and blaNDM) has become a global public health threat. Three CRPA isolates included in the study had an extensively drug-resistant phenotype with susceptibility to colistin only and were positive for the blaNDM-1 gene. The current study aimed to investigate the genomic epidemiology and molecular characteristics of the blaNDM-1-positive CRPA isolates collected from the Gauteng region, South Africa. METHODS: Short read whole genome sequencing (WGS) was performed to determine sequence types (STs), genetic relatedness, resistome, virulome and the genetic environment of the blaNDM-1 gene. RESULTS: The WGS and phylogenetic analyses revealed that the study isolates belonged to an international high-risk clone ST773 and belonged to the same clade with eight blaNDM-1-positive ST773 isolates from Hungary, India, Nigeria, South Korea and USA. The study isolates harboured a wide repertoire of intrinsic and acquired antibiotic resistance genes (ARGs) related with mobile genetic elements, porins and efflux pumps, as well as virulence factor genes. The clade-specific ARGs (blaNDM-1, floR2/cmlA9, rmtB4, tetG) were found in a putative integrative and conjugative element (ICE) region similar to ICE6660-like. CONCLUSION: As ICE carrying the blaNDM-1 gene can easily spread to other P. aeruginosa isolates and other Gram-negative bacteria, the findings in this study highlight the need for appropriate management strategies and active surveillance of CRPA isolates in the Gauteng region, South Africa.


Assuntos
Antibacterianos , Pseudomonas aeruginosa , Humanos , Filogenia , África do Sul/epidemiologia , Antibacterianos/farmacologia , beta-Lactamases/genética , Carbapenêmicos/farmacologia , Genômica , Testes de Sensibilidade Microbiana
16.
Int J Legal Med ; 138(5): 2093-2105, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38649549

RESUMO

Taphonomy studies the environmental effects on remains from the time of deposition to the time of recovery and has been integrated into the field of forensic anthropology. The changes to skeletal remains are dependent on the method of disposal and the surrounding environment. This study focused on buried remains where the type and chemical composition of the soil and the microorganisms present need to be considered. The aim was to investigate the type, frequency, and correlations of the taphonomic alterations of buried domestic pigs. Six taphonomic alterations were observed which included depositional staining, adipocere formation, bone weathering, acidic soil corrosion, and plant, and animal activity. Depositional staining, weathering and plant activity were the most common alterations followed by adipocere which was present on 92.3% of the remains. The bones were mostly stained dark brown and brown; however, the trunk region was the only region to present with black staining. The right sides were darker than the left due to the body positioning as most pigs were placed on their right sides and thus were in direct contact with the cadaver decomposition island. Additionally, the right sides presented with more adipocere as well as increased plant activity suggesting that the soil retained water. Darker stains were correlated with a more complete skeleton as adipocere provides some protection. The study confirms that there are various complicated relationships between different taphonomic alterations. A good understanding of them is needed in forensic anthropology to assist in reconstructing the events that occur after death.


Assuntos
Osso e Ossos , Sepultamento , Antropologia Forense , Mudanças Depois da Morte , Solo , Animais , África do Sul , Suínos , Solo/química , Osso e Ossos/química , Restos Mortais , Modelos Animais
17.
AIDS Behav ; 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-39090458

RESUMO

Antiretroviral therapy (ART) adherence is crucial for health outcomes of people living with HIV (PLHIV), influenced by a complex interplay of individual, community, and household factors. This article focuses on the influence of household factors, as well as individual and community factors, on ART adherence among PLHIV in Cape Town who have recently initiated ART. Baseline data for a cluster-randomized controlled trial were collected from 316 PLHIV in 12 districts in Cape Town between 6th May 2021 and 22nd May 2022. Zero-inflated Poisson models, with cluster-adjusted standard errors, were used to analyse the association between individual, household, and community factors and ART adherence measures. At the household-level, household support was associated with both better self-rated adherence (exp(ß) = 0.81, z = - 4.68, p < 0.001) and fewer days when pills were missed (exp(ß) = 0.65, z = - 2.92, p = 0.003). Psychological violence (exp(ß) = 1.37, z = 1.97, p = 0.05) and higher household asset scores (exp(ß) = 1.29, z = - 2.83, p = 0.05) were weakly associated with poorer ART adherence. At the individual-level, male gender (exp(ß) = 1.37, z = 3.95, p < 0.001) and reinitiating ART (exp(ß) = 1.35, z = 3.64, p < 0.001) were associated with worse self-rated ART adherence; higher education levels (exp(ß) = 0.30 times, z = - 3.75, p < 0.001) and better HIV knowledge (exp(ß) = 0.28, z = - 2.83, p = 0.005) were associated with fewer days where pills were missed. At the community-level, community stigma was associated with worse self-rated ART adherence (exp(ß) = 1.24, z = 3.01, p = 0.003). When designing interventions to improve ART adherence, household, individual and community factors should all be considered, particularly in addressing gender-based disparities, reducing stigma, tackling violence, and enhancing household support.Clinical Trial Number: Pan African Clinical Trial Registry, PACTR201906476052236. Registered on 24 June 2019.


RESUMEN: La adherencia a la terapia antirretroviral (TAR) es crucial para los resultados de salud de las personas que viven con el VIH (PLHIV), influenciada por una compleja interacción de factores individuales, comunitarios y del hogar. Este artículo se centra en la influencia de los factores del hogar, individuales y comunitarios en la adherencia al TAR entre personas que iniciaron recientemente el TAR en Ciudad del Cabo. Se recopilaron datos de referencia para un ensayo de control aleatorio por grupos de 316 PLHIV en 12 distritos de Ciudad del Cabo entre el 6 de mayo de 2021 y el 22 de mayo de 2022. Se utilizaron modelos de Poisson inflados a cero, con errores estándar ajustados por conglomerado para estudiar la asociación entre factores individuales, del hogar o comunitarios con dos medidas de adhesión al TAR: por un lado la auto declaración de adhesión, y por otro la cantidad de días en que se olvidó de tomar la medicina en los últimos 4 días. A nivel del hogar, el apoyo del hogar se asoció con una mejor adherencia auto declarada (exp(ß) = 0.81, z = − 4.68, p < 0.001) y menos días en los que se omitió la medicina (exp(ß) = 0.65, z = − 2.92, p = 0.003). La violencia psicológica (exp(ß) = 1.37, z = 1.97, p = 0.05) y las puntuaciones más altas de activos del hogar (exp(ß) = 1.29, z = − 2.83, p = 0.05) se asociaron con una peor adherencia al TAR. A nivel individual, el sexo masculino (exp(ß) = 1.37, z = 3.95, p < 0.001) y el reinicio del TAR (exp(ß) = 1.35, z = 3.64, p < 0.001) se asociaron con una peor adherencia al TAR autodeclarada; niveles de educación más altos (exp(ß) = 0.30 times, z = − 3.75, p < 0.001) y un mejor conocimiento sobre el VIH (exp(ß) = 0.28, z = − 2.83, p = 0.005) se asociaron con menos días en los que se omitió la medicina. A nivel comunitario, el estigma comunitario se asoció con una peor autodelaración de adhesión del TAR (exp(ß) = 1.24, z = 3.01, p = 0.003). Para mejorar la adherencia al TAR, se deben tener en cuenta los factores del hogar, así como los individuales y comunitarios, particularmente al abordar las disparidades de género, reducir el estigma, abordar la violencia y mejorar el apoyo del hogar.

18.
AIDS Behav ; 28(3): 985-992, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37855843

RESUMO

Although alcohol use is associated with depression, it is unclear if brief alcohol reduction interventions can ameliorate depression and psychological distress among people with HIV (PWH). We use data from a two-arm randomised controlled trial to examine this question. PWH on antiretroviral treatment (ART) were randomly assigned to receive a brief intervention or treatment as usual (n = 622). Screening was done with the Alcohol Use Disorders Identification Test (AUDIT), AUDIT-C, Centre for Epidemiological Studies Depression inventory and Kessler Psychological Distress Scale, at baseline and at 3- and 6-months post-baseline. Changes in depression and psychological distress was assessed using analysis of covariance models with baseline measures of alcohol consumption, sex and age included as covariates and adjusting for baseline symptom severity. Changes in alcohol consumption between baseline and follow-up were included in the analysis to establish if this affected outcomes. For both the intervention and control groups, there were significant reductions in symptom severity at 3-months and 6-months for depression and psychological distress, but no significant between group differences were observed. Reductions in alcohol consumption were significantly associated with reductions in depression and psychological distress, supporting the hypothesis that alcohol use is linked to depression among PWH.Trial Registration Pan African Clinical Trials Register, PACTR201405000815100.nh.


Assuntos
Alcoolismo , Infecções por HIV , Humanos , Alcoolismo/diagnóstico , Depressão/complicações , Depressão/epidemiologia , Depressão/terapia , África do Sul/epidemiologia , Infecções por HIV/complicações , Infecções por HIV/epidemiologia , Infecções por HIV/psicologia , Consumo de Bebidas Alcoólicas/epidemiologia , Consumo de Bebidas Alcoólicas/psicologia
19.
AIDS Behav ; 2024 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-39245761

RESUMO

Social networks expand rapidly in adolescence, increasing HIV status disclosure considerations and concerns for young people living with HIV, especially in settings where HIV-related stigma is prevalent. This study examines HIV disclosure and enacted stigma among adolescents and young adults living with HIV in South Africa. This study uses survey data from a sample of 1186 youth living with HIV, aged 14-24, and enrolled in peer support groups led by community-based organizations in KwaZulu Natal and Gauteng provinces, South Africa. Study participants completed a questionnaire on sociodemographic details, physical health, school attendance, who knew the individual's HIV status, and experiences of HIV-related mistreatment. Mixed effects logistic regression examined the association between experiences of HIV-related mistreatment and factors that may inadvertently disclose one's status, such as poor physical health and missed school, and knowledge of an individual's HIV-positive status by their caregiver, household, friends, educators, and most recent sexual partner. Almost a quarter of the sample reported an experience of HIV-related mistreatment in the past six months. After controlling sociodemographic characteristics, missed school due to illness (AOR = 1.75, 95% CI = 1.27-2.43), and knowledge of HIV status by non-family members (AOR = 2.19, 95% CI = 1.60-3.00) were significantly associated with HIV-related mistreatment. Findings suggest that experiences of enacted stigma are common among youth and linked to poor physical health and knowledge of HIV status outside the family. Effective community-level stigma reduction interventions are urgently needed. In the meantime, adolescents need individualized disclosure counseling and support managing their physical health to prevent further inadvertent disclosure and discrimination.

20.
AIDS Behav ; 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38985402

RESUMO

The provision of ART in South Africa has transformed the HIV epidemic, resulting in an increase in life expectancy by over 10 years. Despite this, nearly 2 million people living with HIV are not on treatment. The objective of this study was to develop and externally validate a practical risk assessment tool to identify people with HIV (PWH) at highest risk for attrition from care after testing. A machine learning model incorporating clinical and psychosocial factors was developed in a primary cohort of 498 PWH. LASSO regression analysis was used to optimize variable selection. Multivariable logistic regression analysis was applied to build a model using 80% of the primary cohort as a training dataset and validated using the remaining 20% of the primary cohort and data from an independent cohort of 96 participants. The risk score was developed using the Sullivan and D'Agostino point based method. Of 498 participants with mean age 35.7 years, 192 (38%) did not initiate ART after diagnosis. Controlling for site, factors associated with non-engagement in care included being < 35 years, feeling abandoned by God, maladaptive coping strategies using alcohol or other drugs, no difficulty concentrating, and having high levels of confidence in one's ability to handle personal challenges. An effective risk score can enable clinicians and implementers to focus on tailoring care for those most in need of ongoing support. Further research should focus on potential strategies to enhance the generalizability and evaluate the implementation of the proposed risk prediction model in HIV treatment programs.


RESUMEN: La provisión de TAR (Terapia Antirretroviral) en Sudáfrica ha transformado la epidemia del VIH, resultando en un aumento de la esperanza de vida de más de 10 años. Los últimos objetivos de tratamiento del VIH se sitúan en 94-75-92, con brechas notables después de las pruebas. El objetivo de este estudio fue desarrollar y validar externamente una herramienta práctica de evaluación de riesgos para identificar a las personas con VIH (PVH) con mayor riesgo de deserción del cuidado después de las pruebas. Se desarrolló un modelo sencillo de aprendizaje automático que incorpora factores clínicos y psicosociales en una cohorte primaria de 498 PVH. Se utilizó el análisis de regresión LASSO para optimizar la selección de variables. Se aplicó un análisis de regresión logística multivariable para construir un modelo usando el 80% de la cohorte primaria como conjunto de datos de entrenamiento y validado usando el 20% restante de la cohorte primaria y datos de una cohorte independiente de 96 participantes. El puntaje de riesgo se desarrolló utilizando el método basado en puntos de Sullivan y D'Agostino. De los 498 participantes con una edad media de 35,7 años, 192 (38%) no iniciaron TAR después del diagnóstico. Controlando por sitio, los factores asociados con la no participación en el cuidado incluyeron tener menos de 35 años, sentirse abandonado por Dios, estrategias de afrontamiento desadaptativas usando alcohol u otras drogas, no tener dificultades para concentrarse y tener altos niveles de confianza en la capacidad de manejar desafíos personales. Un puntaje de riesgo efectivo puede permitir a los clínicos y ejecutores enfocarse en personalizar el cuidado para aquellos que más necesitan apoyo continuo. Las investigaciones futuras deben centrarse en estrategias potenciales para mejorar la generalización y evaluar la implementación del modelo de predicción de riesgo propuesto en los programas de tratamiento del VIH.

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