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BACKGROUND: COVID-19 waves caused by specific SARS-CoV-2 variants have occurred globally at different times. We focused on Omicron variants to understand the genomic diversity and phylogenetic relatedness of SARS-CoV-2 strains in various regions of Pakistan. METHODS: We studied 276,525 COVID-19 cases and 1,031 genomes sequenced from December 2021 to August 2022. Sequences were analyzed and visualized using phylogenetic trees. RESULTS: The highest case numbers and deaths were recorded in Sindh and Punjab, the most populous provinces in Pakistan. Omicron variants comprised 93% of all genomes, with BA.2 (32.6%) and BA.5 (38.4%) predominating. The first Omicron wave was associated with the sequential identification of BA.1 in Sindh, then Islamabad Capital Territory, Punjab, Khyber Pakhtunkhwa (KP), Azad Jammu Kashmir (AJK), Gilgit-Baltistan (GB) and Balochistan. Phylogenetic analysis revealed Sindh to be the source of BA.1 and BA.2 introductions into Punjab and Balochistan during early 2022. BA.4 was first introduced in AJK and BA.5 in Punjab. Most recent common ancestor (MRCA) analysis revealed relatedness between the earliest BA.1 genome from Sindh with Balochistan, AJK, Punjab and ICT, and that of first BA.1 from Punjab with strains from KPK and GB. CONCLUSIONS: Phylogenetic analysis provides insights into the introduction and transmission dynamics of the Omicron variant in Pakistan, identifying Sindh as a hotspot for viral dissemination. Such data linked with public health efforts can help limit surges of new infections.
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COVID-19 , Humanos , COVID-19/epidemiologia , Paquistão/epidemiologia , Filogenia , SARS-CoV-2/genéticaRESUMO
BACKGROUND: Enteric fever is an acute systemic infectious disease associated with substantial morbidity and mortality in low- and middle-income countries (LMIC), with a global burden of 14.3 million cases. Cases of enteric fever or paratyphoid fever, caused by Salmonella enterica serovar Paratyphi A (S. Para A) have been found to rise in many endemic and non-endemic countries. Drug resistance is relatively uncommon in S. Para A. Here we report a case of paratyphoid fever caused by ceftriaxone resistant S. Para A from Pakistan. CASE PRESENTATION: A 29-year-old female presented with a history of fever, headache, and shivering. Her blood culture revealed a S. Para A isolate (S7), which was resistant to ceftriaxone, cefixime, ampicillin and ciprofloxacin. She was prescribed oral Azithromycin for 10 days, which resulted in resolution of her symptoms. Two other isolates of S. Para A (S1 and S4), resistant to fluoroquinolone were also selected for comparison. DST and whole genome sequencing was performed for all three isolates. Sequence analysis was performed for identification of drug resistance and phylogeny. Whole Genome Sequencing (WGS) of S7 revealed the presence of plasmids, IncX4 and IncFIB(K). blaCTX-M-15 and qnrS1 genes were found on IncFIB(K). The gyrA S83F mutation conferring fluoroquinolone resistance was also found present. Multi-locus sequence typing (MLST) showed the S7 isolate to belong to ST129. S1 and S4 had the gyrA S83Y and S83F mutations respectively. CONCLUSIONS: We highlight the occurrence of plasmid-mediated ceftriaxone resistant strain of S. Para A. This is of significance as ceftriaxone is commonly used to treat paratyphoid fever and resistance in S. Para A is not known. Continuous epidemiological surveillance is required to monitor the transmission and spread of antimicrobial resistance (AMR) among Typhoidal Salmonellae. This will guide treatment options and preventive measures including the need for vaccination against S. Para A in the region.
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Febre Paratifoide , Febre Tifoide , Humanos , Feminino , Adulto , Febre Tifoide/epidemiologia , Ceftriaxona/farmacologia , Ceftriaxona/uso terapêutico , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Salmonella paratyphi A/genética , Tipagem de Sequências Multilocus , Febre Paratifoide/diagnóstico , Febre Paratifoide/tratamento farmacológico , Salmonella typhi , Paquistão , Fluoroquinolonas , Farmacorresistência Bacteriana/genética , Testes de Sensibilidade MicrobianaRESUMO
BACKGROUND: Protection against SARS-CoV-2 is mediated by humoral and T cell responses. Pakistan faced relatively low morbidity and mortality from COVID-19 through the pandemic. To examine the role of prior immunity in the population, we studied IgG antibody response levels, virus neutralizing activity and T cell reactivity to Spike protein in a healthy control group (HG) as compared with COVID-19 cases and individuals from the pre-pandemic period (PP). METHODS: HG and COVID-19 participants were recruited between October 2020 and May 2021. Pre-pandemic sera was collected before 2018. IgG antibodies against Spike and its Receptor Binding Domain (RBD) were determined by ELISA. Virus neutralization activity was determined using a PCR-based micro-neutralization assay. T cell - IFN-γ activation was assessed by ELISpot. RESULTS: Overall, the magnitude of anti-Spike IgG antibody levels as well as seropositivity was greatest in COVID-19 cases (90%) as compared with HG (39.8%) and PP (12.2%). During the study period, Pakistan experienced three COVID-19 waves. We observed that IgG seropositivity to Spike in HG increased from 10.3 to 83.5% during the study, whilst seropositivity to RBD increased from 7.5 to 33.3%. IgG antibodies to Spike and RBD were correlated positively in all three study groups. Virus neutralizing activity was identified in sera of COVID-19, HG and PP. Spike reactive T cells were present in COVID-19, HG and PP groups. Individuals with reactive T cells included those with and without IgG antibodies to Spike. CONCLUSIONS: Antibody and T cell responses to Spike protein in individuals from the pre-pandemic period suggest prior immunity against SARS-CoV-2, most likely from cross-reactive responses. The rising seroprevalence observed in healthy individuals through the pandemic without known COVID-19 may be due to the activation of adaptive immunity from cross-reactive memory B and T cells. This may explain the more favourable COVID-19 outcomes observed in this population.
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COVID-19 , SARS-CoV-2 , Humanos , COVID-19/epidemiologia , Paquistão/epidemiologia , Pandemias , Estudos Soroepidemiológicos , Glicoproteína da Espícula de Coronavírus , Linfócitos T , Imunoglobulina G , ELISPOT , Anticorpos Antivirais , Anticorpos Neutralizantes , Imunidade HumoralRESUMO
BACKGROUND: Mutations in the Rv0678, pepQ and atpE genes of Mycobacterium tuberculosis (MTB) have been reported to be associated with reduced antimycobacterial susceptibility to bedaquiline (BDQ). Resistance conferring mutations in treatment naïve MTB strains is likely to have implications for BDQ based new drug regimen that aim to shorten treatment duration. We therefore investigated the genetic basis of resistance to BDQ in MTB clinical isolates from BDQ naïve TB patients from Pakistan. In addition, mutations in genes associated with efflux pumps were investigated as an alternate mechanism of resistance. METHODS: Based on convenience sampling, we studied 48 MTB clinical isolates from BDQ naïve TB patients. These isolates (from our strain bank) included 38 MDR/pre-XDR/XDR (10 BDQ resistant, 8 BDQ intermediate and 20 BDQ susceptible) and 10 pan drug susceptible MTB isolates. All strains were subjected to whole genome sequencing and genomes were analysed to identify variants in Rv0678, pepQ, atpE, Rv1979c, mmpLS and mmpL5 and drug resistance associated efflux pump genes. RESULTS: Of the BDQ resistant and intermediate strains 44% (8/18) had variants in Rv0678 including; two reported mutations S63R/G, six previously unreported variants; L40F, R50Q and R107C and three frameshift mutations; G25fs, D64fs and D109fs. Variants in efflux pumps; Rv1273c (G462K), Rv0507c (R426H) and Rv1634c (E198R) were found to be present in drug resistant isolates including BDQ resistant and intermediate isolates. E198R in efflux pump gene Rv1634c was the most frequently occurring variant in BDQ resistant and intermediate isolates (n = 10). CONCLUSION: We found RAVs in Rv0678 to be commonly associated with BDQ resistance. Further confirmation of the role of variants in efflux pump genes in resistance is required so that they may be incorporated in genome-based diagnostics for drug resistant MTB.
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Mycobacterium tuberculosis , Tuberculose Resistente a Múltiplos Medicamentos , Antituberculosos/farmacologia , Diarilquinolinas , Humanos , Testes de Sensibilidade Microbiana , Mutação , Mycobacterium tuberculosis/genética , Paquistão , Tuberculose Resistente a Múltiplos Medicamentos/microbiologiaRESUMO
Tuberculosis (TB) outcomes are worsened by type II diabetes mellitus (DM). Protective immunity against Mycobacterium tuberculosis (MTB) is driven by cytokines. Latent TB (LTBi) is common but its effect on the diabetic host is not well understood. We investigated mycobacterial antigen-stimulated responses in peripheral blood mononuclear cell (PBMC) isolated from healthy endemic controls (EC), those with LTBi, DM groups with and without LTBi, as compared with TB patients. Cytokines were measured using a Luminex-based assay. Gene expression was determined by RT-PCR. In DM-LTBi cases, PPD-stimulated proinflammatory cytokines; IFN-γ, IL-6, IL-2, TNF-α and GM-CSF and anti-inflammatory cytokines, IL-5 and IL-13 were raised as compared with EC. DM-LTBi PPD-stimulated IFN-γ, IL-6 and TNF-α mRNA titres were found raised in DM-LTBi, whilst suppressor of cytokine signalling (SOCS)-3 expression was lowered. Within DM cases, stratification based on HbA1c levels revealed raised IFN-γ but lowered IL-6 gene expression in those with controlled levels as compared with uncontrolled glycaemic levels. Further, SOCS1 expression levels were found higher in DM cases with controlled glycaemia when compared with EC. Overall, we show that diabetics with LTBi manifest raised levels of inflammatory and anti-inflammatory cytokines concomitant with reduced SOCS3 mRNA expression. Reduced glycaemic control results in further inflammatory dysregulation impacting conversing impacting IFN-γ and IL-6 activation. These results suggest that dysregulated immune activation in diabetes is exacerbated by LTBi, lack of glycaemic control may further compromise immunity against MTB infection.
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Diabetes Mellitus Tipo 2 , Tuberculose Latente , Mycobacterium tuberculosis , Tuberculose , Antígenos de Bactérias , Citocinas/metabolismo , Humanos , Leucócitos MononuclearesRESUMO
Tuberculosis (TB), caused by infection with mycobacterium tuberculosis, is a major source of morbidity and mortality in Pakistan. Diabetes caused by imbalance in glycaemic control is also highly prevalent in the country. The coincidence of both diseases results in worsening outcomes of TB, making treatment and management more difficult. Both innate and adaptive arms of the host immune response are required for protection against M. tuberculosis infection. Host immunity is modified in diabetes mellitus type 2 where key pathways such as, the T cell driven interferon-gamma responses to M. tuberculosis antigens and other T cell and macrophage activating cytokines are suppressed. This makes diabetes with TB a more severe disease and results in worse treatment outcomes. Effective coordination between T cells and host macrophages is required for control of TB infection. Therefore, early identification of diabetes and management of hyperglycaemia during TB treatment is essential for favourable outcomes.
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Diabetes Mellitus Tipo 2 , Imunidade Celular , Tuberculose , Diabetes Mellitus Tipo 2/complicações , Diabetes Mellitus Tipo 2/imunologia , Humanos , Tuberculose Latente/imunologia , Tuberculose/complicações , Tuberculose/imunologiaRESUMO
OBJECTIVE: To investigate pre-diabetes and diabetes in newly-diagnosed tuberculosis patients and to assess the association of serum cytokine levels with diabetes status. METHODS: The cross-sectional study was conducted at Indus Hospital and The Aga Khan University Hospital, Karachi from May to November 2015, and included patients of either gender aged 18 years or more with a confirmed diagnosis of tuberculosis who were either newly diagnosed or had received up to 1 month of anti-tuberculosis therapy were included. Patients were enrolled from among those presenting to the clinics at Indus Hospital, Karachi, and the Department of Medicine, Aga Khan University Hospital (AKUH), Karachi. The patients were tested for glycosylated haemoglobin and random blood glucose. Diabetes was defined as HbA1c >6.5%; pre-diabetes as HbA1c=5.7-6.4%; and normoglycaemic as HbA1c <5.7%. Serum cytokines were investigated using the Bio-plex 27, Bio-Rad assay. SPSS version 19.0 was used for data analysis.. RESULTS: Of the 211 subjects, 110(52%) were females and 101(48%) were males. The overall median age of the sample was 26 years, and 100(47.3%) subjects were underweight. Of the total, 24(11.4%) had diabetes and 45(21.3%) had pre-diabetes. Of the diabetics, only 7(29%) knew their status prior to screening. Interferon-gamma and interleukin-13 were significantly different among tuberculosis patients with diabetes, pre-diabetes and normoglycaemia (p<0.05). Glycosylated haemoglobin levels showed a significant correlation with interferon-gamma levels. CONCLUSIONS: Raised interleukin-13 and interferon-gamma levels in newly-diagnosed tuberculosis patients with pre-diabetes.
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Interferon gama/imunologia , Interleucina-13/imunologia , Estado Pré-Diabético/imunologia , Tuberculose/imunologia , Adulto , Glicemia/metabolismo , Diabetes Mellitus/epidemiologia , Diabetes Mellitus/imunologia , Diabetes Mellitus/metabolismo , Feminino , Hemoglobinas Glicadas/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Estado Pré-Diabético/epidemiologia , Estado Pré-Diabético/metabolismo , Tuberculose/diagnóstico , Tuberculose/epidemiologia , Adulto JovemRESUMO
OBJECTIVE: To evaluate the trends in usage of dengue virus diagnostics in Pakistan. METHODS: This retrospective study was conducted at the Aga Khan University Hospital, Karachi, and comprised data for specimens tested for dengue virus from January 2012 to December 2015. Test for dengue virus ribonucleic acid by reverse transcription polymerase chain reaction, dengue virus antigen by immunochromatic assay and for human immunoglobulin M against dengue virus by enzyme-linked immunosorbent assay were reviewed. SPSS 17 was used for data analysis. RESULTS: Overall, 33,577 specimens tested for dengue virus. Of them, 11,995 (35.7%) were positive. among them, 1,039(8.66%) were reported in 2012; 5,791(48.28%) in 2013; 1,027(8.56%) in 2014; and 4,138(34.49%) in 2015. In 2012, 966(93%) of the positive samples were diagnosed by immunoglobulin M-based method and 73(7%) by non-structural protein-1 antigen. In 2013, 4,401(76%) samples were tested positive by immunoglobulin M, 1,332(23%) by antigen and 58(1%) by polymerase chain reaction. The trend continued in 2014, but in 2015, 2,111(51%) of all dengue positive tests were determined by antigen testing, 1,969(47.6%) by immunoglobulin M and 58(1.4%) by polymerase chain reaction. CONCLUSIONS: There was a shift in usage of direct virus identification for rapid diagnosis of dengue virus compared with host immunoglobulin M testing.
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Anticorpos Antivirais/sangue , Antígenos Virais/sangue , Vírus da Dengue , Dengue/diagnóstico , Imunoglobulina M/imunologia , RNA Viral/sangue , Adulto , Anticorpos Antivirais/imunologia , Antígenos Virais/imunologia , Dengue/sangue , Dengue/imunologia , Vírus da Dengue/genética , Vírus da Dengue/imunologia , Ensaio de Imunoadsorção Enzimática/métodos , Feminino , Humanos , Imunoensaio/métodos , Masculino , Pessoa de Meia-Idade , Paquistão , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa/métodos , Fatores de Tempo , Proteínas não Estruturais Virais/sangue , Proteínas não Estruturais Virais/imunologia , Adulto JovemRESUMO
BACKGROUND: Approximately 10% of the Mycobacterium tuberculosis genome is made up of two families of genes that are poorly characterized due to their high GC content and highly repetitive nature. The PE and PPE families are typified by their highly conserved N-terminal domains that incorporate proline-glutamate (PE) and proline-proline-glutamate (PPE) signature motifs. They are hypothesised to be important virulence factors involved with host-pathogen interactions, but their high genetic variability and complexity of analysis means they are typically disregarded in genome studies. RESULTS: To elucidate the structure of these genes, 518 genomes from a diverse international collection of clinical isolates were de novo assembled. A further 21 reference M. tuberculosis complex genomes and long read sequence data were used to validate the approach. SNP analysis revealed that variation in the majority of the 168 pe/ppe genes studied was consistent with lineage. Several recombination hotspots were identified, notably pe_pgrs3 and pe_pgrs17. Evidence of positive selection was revealed in 65 pe/ppe genes, including epitopes potentially binding to major histocompatibility complex molecules. CONCLUSIONS: This, the first comprehensive study of the pe and ppe genes, provides important insight into M. tuberculosis diversity and has significant implications for vaccine development.
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Genes Bacterianos , Família Multigênica , Mycobacterium tuberculosis/genética , Polimorfismo de Nucleotídeo Único , Recombinação Genética , DNA Bacteriano/genética , Evolução Molecular , Genoma Bacteriano , Genômica/métodos , Genótipo , Mutação , Filogenia , Seleção Genética , Análise de Sequência de DNARESUMO
BACKGROUND: Cardiopulmonary bypass is associated with systemic inflammatory response. Steroids suppress this response, although the therapeutic evidence remains controversial. We hypothesised that intravenous steroids in children undergoing open-heart surgery would decrease inflammation leading to better early post-operative outcomes. We conducted a randomised controlled trial to evaluate the trends in the levels of immunomodulators and their effects on clinical parameters. OBJECTIVE: To assess the effects of intravenous steroids on early post-operative inflammatory markers and clinical parameters in children undergoing open-heart surgery. MATERIALS AND METHODS: A randomised controlled trial involving 152 patients, from one month up to 18 years of age, who underwent open-heart surgery for congenital heart disease from April 2010-2012 was carried out. Patients were randomised and administered either three scheduled intravenous pulse doses of dexamethasone (1 mg/kg) or placebo. Blood samples were drawn at four time intervals and serum levels of inflammatory cytokines - Interleukin-6, 8, 10, 18, and tumour necrosis factor-alpha - were measured. Clinical parameters were also assessed. RESULTS: Blood cytokine levels were compared between the dexamethasone (n=65) and placebo (n=64) groups. Interleukin-6 levels were lower at 6 and 24 hours post-operatively (p<0.001), and Interleukin-10 levels were higher 6 hours post-operatively (p<0.001) in the steroid group. Interleukin-8, 18, and tumour necrosis factor-alpha levels did not differ between the groups at any time intervals. The clinical parameters were similar in both the groups. CONCLUSION: Dexamethasone caused quantitative suppression of Interleukin-6 and increased Interleukin-10 activation, contributing to reduced immunopathology, but it did not translate into clinical benefit in the short term.
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Ponte Cardiopulmonar/efeitos adversos , Citocinas/sangue , Dexametasona/administração & dosagem , Cardiopatias Congênitas/terapia , Inflamação/sangue , Fator de Necrose Tumoral alfa/sangue , Administração Intravenosa , Adolescente , Biomarcadores/sangue , Criança , Pré-Escolar , Método Duplo-Cego , Feminino , Cardiopatias Congênitas/sangue , Humanos , Lactente , Inflamação/prevenção & controle , Masculino , PaquistãoRESUMO
INTRODUCTION: Single-nucleotide variants (SNVs) in Mycobacterium tuberculosis (M. tuberculosis) genomes can predict multidrug resistance (MDR) but not all phenotype-genotype correlations can be explained. We investigated SNVs in efflux pumps (EPs) in the context of M. tuberculosis drug resistance. METHODS: We analysed 2221 M. tuberculosis genomes from 1432 susceptible and 200 MDR, 172 pre-extensively drug resistant (XDR) and 417 XDR isolates. Analysis of 47 EP genes was conducted using MTB-VCF, an in-house bioinformatics pipeline. SNVs were categorized according to their SIFT/Polyphen scores. Resistance genotypes were also called using the TB-Profiler tool. RESULTS: Genome comparisons between susceptible and drug resistant (DR) isolates identified 418 unique SNVs in EP of which; 53.5% were in MDR, 68.9% in pre-XDR and 61.3% in XDR isolates. Twenty EPs had unique SNVs with a high SIFT/PolyPhen score, comprising 38 unique SNVs. Sixteen SNVs across 12 EP genes were significantly associated with drug resistance and enriched in pre-XDR and XDR strains. These comprised 12 previously reported SNVs (in Rv0191, Rv0507, Rv0676, Rv1217, Rv1218, Rv1273, Rv1458, Rv1819, and Rv2688) and 4 novel SNVs (in Rv1877 and Rv2333). We investigated their presence in genomes of 52 MDR isolates with phenotype-genotype discrepancies to rifampicin (RIF), isoniazid (INH), or fluoroquinolones. SNVs associated with RIF and INH (Rv1217_1218, Rv1819, Rv0450, Rv1458, Rv3827, Rv0507, Rv0676, Rv1273, and Rv2333), and with fluoroquinolone (Rv2688) resistance were present in these discrepant strains. CONCLUSIONS: Considering SNVs in EPs as part of M. tuberculosis genome-based resistance interpretation may add value, especially in evaluation of XDR resistance in strains with phenotype-genotype discrepancies.
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BACKGROUND: COVID-19 epidemiology changed with the emergence of SARS-CoV-2 variants of concern (VOC). Pakistan administered mostly inactivated vaccines. We investigated the association between VOC and breakthrough infections in a mixed-vaccination-status population of Karachi. METHODS: We investigated SARS-CoV-2 VOC tested in 392 respiratory specimens collected between May and December 2021. Data for age, sex, hospital admission, vaccinations, together with CT values of the diagnostic PCR test were analyzed. RESULTS: The median age of COVID-19 cases tested was 40 (27-57) years and 43.4% were female. Delta variants were most common (56.4%) followed by Alpha (15.9%), Omicron (12.2%), Beta/Gamma (11.3%), and others (4.3%). Eighteen percent of cases were hospitalized whereby, predominant VOC were Beta/Gamma (40.8%), Alpha (35.2%) and Delta (22.5%). Overall, 55.4% of individuals were fully vaccinated, 7.4% were partially vaccinated and 37.2% were unvaccinated. Most (74.6%) inpatients were unvaccinated. Vaccines comprised inactivated (85.34%), single-shot vector (8.62%), two-shot vector (3.02%) and mRNA (3.02%) types. Omicron variants showed lower viral loads as compared to Alpha, Beta/Gamma, and Delta (p = 0.017). The risk of infection with Delta and Omicron variants was higher, 8 weeks after vaccination. The majority of those with breakthrough infections after receiving inactivated vaccines acquired COVID-19 within 4 months of vaccination. CONCLUSION: Our data highlights the shifting of VOC from Delta to Omicron during 2021 and that COVID-19 vaccinations reduced both hospitalizations and viral transmission. It informs on the increased risk of breakthrough infection within 8 weeks of vaccination, indicating the need for booster vaccinations.
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Vacinas contra COVID-19 , COVID-19 , Hospitalização , SARS-CoV-2 , Humanos , COVID-19/epidemiologia , COVID-19/prevenção & controle , COVID-19/virologia , Feminino , Masculino , SARS-CoV-2/genética , SARS-CoV-2/imunologia , Adulto , Pessoa de Meia-Idade , Vacinas contra COVID-19/administração & dosagem , Vacinas contra COVID-19/imunologia , Hospitalização/estatística & dados numéricos , Paquistão/epidemiologia , Índice de Gravidade de Doença , Vacinação/estatística & dados numéricos , Infecções IrruptivasRESUMO
BACKGROUND: In early 2021, the 10-valent Pneumococcal conjugate vaccine (PCV10) was replaced with 13-valent (PCV13) by the federal directorate of immunization (FDI), Pakistan. We assessed the impact of a higher valent vaccine, PCV13, on the serotype distribution of nasopharyngeal carriage in rural Pakistan. METHODS: Children <2 years were randomly selected from two rural union councils of Matiari, Sindh in Pakistan between September-October,2022. Clinical, sociodemographic and vaccination histories were recorded. Nasopharyngeal swabs were collected and processed at Infectious Disease Research Laboratory, Aga Khan University, Karachi. Whole genome sequencing was performed on the culture positive isolates. RESULTS: Of the 200 children enrolled, pneumococcus was detected in 140(70 %) isolates. Majority of age-eligible children (60.1 %,110/183) received 3 PCV13 doses. PCV10 carriage declined from 13.2 %(78/590) in 2017/18 to 7.2 % (10/140) in 2022, additional PCV13 serotypes (3, 6A/6C and 19A) decreased from 18.5 %(109/590) to 11.4 %(16/140) while non-PCV13 serotypes increased from 68.3 %(403/590) to 81.4 %(114/140). There were 88.5 %(n = 124), 80.7 %(n = 113), 55.0 %(n = 77), and 46.0 %(n = 65) isolates predicted to be resistant to cotrimoxazole, penicillin(meningitis cut-off), tetracycline, and erythromycin respectively. CONCLUSION: Replacing PCV10 with PCV13 rapidly decreased prevalence of PCV13 carriage among vaccinated children in Matiari, Pakistan. Vaccine-driven selection pressure may have been responsible for the increase of non-PCV13 serotypes.
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Crimean-Congo hemorrhagic fever (CCHF) is endemic in the Baluchistan province, Pakistan. Sporadic outbreaks of CCHF occur throughout the year especially in individuals in contact with infected livestock. Nosocomial transmission remains a risk due to difficulties in the diagnosis of CCHF and limited availability of facilities for the isolation of suspected patients. Rapid diagnosis of CCHF virus infection is required for early management of the disease and to prevent transmission. This study describes the case of a 43-year-old surgeon who contracted CCHF during a surgical procedure in Quetta, Baluchistan and who was transferred to a tertiary care facility at the Aga Khan University Hospital, Karachi within 1 week of contracting the infection. Diagnosis of CCHF was made using a rapid real-time reverse transcription polymerase chain reaction (RT-PCR) assay for CCHF viral RNA. The patient had chronic hepatitis B and hepatitis D infection for which he had previously received a liver transplant. He proceeded to develop classic hemorrhagic manifestations and succumbed to the infection 14 days post-onset of disease. There was no further nosocomial transmission of the CCHF during the hospital treatment of the surgeon. Early diagnosis of CCHF enables rapid engagement of appropriate isolation, barrier nursing and infection control measures thus preventing nosocomial transmission of the virus.
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Infecção Hospitalar/diagnóstico , Vírus da Febre Hemorrágica da Crimeia-Congo/isolamento & purificação , Febre Hemorrágica da Crimeia/diagnóstico , Adulto , Infecção Hospitalar/patologia , Infecção Hospitalar/virologia , Febre Hemorrágica da Crimeia/patologia , Febre Hemorrágica da Crimeia/virologia , Humanos , Hospedeiro Imunocomprometido , Masculino , Dados de Sequência Molecular , Paquistão , RNA Viral/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Análise de Sequência de DNARESUMO
BACKGROUND: Even though dengue has been recognized as one of the major public health threats in Pakistan, the understanding of its molecular epidemiology is still limited. The genotypic diversity of Dengue virus (DENV) serotypes involved in dengue outbreaks since 2005 in Pakistan is not well studied. Here, we investigated the origin, diversity, genetic relationships and geographic distribution of DENV to understand virus evolution during the recent expansion of dengue in Pakistan. METHODS: The study included 200 sera obtained from dengue-suspected patients from 2006 to 2011. DENV infection was confirmed in 94 (47%) sera by a polymerase chain reaction assay. These included 36 (38.3%) DENV-2, 57 DENV-3 (60.6%) and 1 DENV-4 (1.1%) cases. Sequences of 13 whole genomes (6 DENV-2, 6 DENV-3 and 1 DENV-4) and 49 envelope genes (26 DENV-2, 22 DENV-3 and 1 DENV-4) were analysed to determine the origin, phylogeny, diversity and selection pressure during virus evolution. RESULTS: DENV-2, DENV-3 and DENV-4 in Pakistan from 2006 to 2011 shared 98.5-99.6% nucleotide and 99.3-99.9% amino acid similarity with those circulated in the Indian subcontinent during the last decade. Nevertheless, Pakistan DENV-2 and DENV-3 strains formed distinct clades characterized by amino acid signatures of NS2A-I116T + NS5-K861R and NS3-K590R + NS5-S895L respectively. Each clade consisted of a heterogenous virus population that circulated in Southern (2006-2009) and Northern Pakistan (2011). CONCLUSIONS: DENV-2, DENV-3 and DENV-4 that circulated during 2006-2011 are likely to have first introduced via the southern route of Pakistan. Both DENV-2 and DENV-3 have undergone in-situ evolution to generate heterogenous populations, possibly driven by sustained local DENV transmission during 2006-2011 periods. While both DENV-2 and DENV-3 continued to circulate in Southern Pakistan until 2009, DENV-2 has spread in a Northern direction to establish in Punjab Province, which experienced a massive dengue outbreak in 2011.
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Vírus da Dengue/classificação , Vírus da Dengue/genética , Dengue/virologia , Variação Genética , Análise por Conglomerados , Estudos de Coortes , Dengue/epidemiologia , Vírus da Dengue/isolamento & purificação , Humanos , Epidemiologia Molecular , Dados de Sequência Molecular , Paquistão/epidemiologia , Filogeografia , RNA Viral/genética , Análise de Sequência de DNA , Homologia de SequênciaRESUMO
BACKGROUND: Vitamin D enhances host protective immune responses to Mycobacterium tuberculosis by suppressing Interferon-gamma (IFN-g) and reducing disease associated inflammation in the host. The objectives of this study were to determine whether vitamin D supplementation to patients with tuberculosis (TB) could influence recovery. METHODS: Two hundred and fifty nine patients with pulmonary TB were randomized to receive either 600,000 IU of Intramuscular vitamin D3 or placebo for 2 doses. Assessments were performed at 4, 8 and 12 weeks. Early secreted and T cell activated 6 kDa (ESAT6) and Mycobacterium tuberculosis sonicate (MTBs) antigen induced whole blood stimulated IFN-g responses were measured at 0 and 12 weeks. Statistical comparisons between outcome variables at 0 and 12 weeks were performed using Student's t-test and Chi2 tests. RESULTS: After 12 weeks, the vitamin D supplemented arm demonstrated significantly greater mean weight gain (kg)+3.75, (3.16-4.34) versus+2.61 (95% CI 1.99-3.23) p 0.009 and lesser residual disease by chest radiograph; number of zones involved 1.35 v/s 1.82 p 0.004 (95% CI 0.15, 0.79) and 50% or greater reduction in cavity size 106 (89.8%) v/s 111 (94.8%), p 0.035. Vitamin D supplementation led to significant increase in MTBs-induced IFN-g secretion in patients with baseline 'Deficient' 25-hydroxyvitamin D serum levels (p 0.021). CONCLUSIONS: Supplementation with high doses of vitamin D accelerated clinical, radiographic improvement in all TB patients and increased host immune activation in patients with baseline 'Deficient' serum vitamin D levels. These results suggest a therapeutic role for vitamin D in the treatment of TB. TRIAL REGISTRATION: ClinicalTrials.gov; No. NCT01130311; URL: clinicaltrials.gov.
Assuntos
Suplementos Nutricionais , Tuberculose Pulmonar/tratamento farmacológico , Vitamina D/uso terapêutico , Adolescente , Adulto , Antígenos de Bactérias/imunologia , Proteínas de Bactérias/imunologia , Feminino , Humanos , Interferon gama/sangue , Interferon gama/imunologia , Masculino , Mycobacterium tuberculosis/imunologia , Resultado do Tratamento , Tuberculose Pulmonar/sangue , Tuberculose Pulmonar/imunologia , Vitamina D/análogos & derivados , Vitamina D/sangue , Adulto JovemRESUMO
BACKGROUND: Appropriate immune activation of T cells and macrophages is central for the control of Mycobacterium tuberculosis infections. IFN-γ stimulated responses are lowered in tuberculosis (TB), while expression of Suppressor of Cytokine Signaling (SOCS) molecules - 1 and 3 and CD4+CD25+FoxP3+T regulatory cells is increased. Here we investigated the association of these molecules in regard to clinical severity of TB. METHODS: Peripheral blood mononuclear cells (PBMCs) were isolated from patients with pulmonary TB (PTB, n = 33), extra-pulmonary TB (ETB, n = 33) and healthy endemic controls (EC, n = 15). Cases were classified as moderately advanced or far advanced PTB, and less severe or severe disseminated ETB. M. tuberculosis -stimulated IFN-γ, SOCS1, SOCS3 and FoxP3 gene expression and secretion of Th1 and Th2 cytokines was measured. Statistical analysis was performed using Mann-Whitney U, Wilcoxon Rank and Kruskal Wallis non-parametric tests. RESULTS: In un-stimulated PBMCs, IL-6 (p = 0.018) and IL-10 (p = 0.013) secretion levels were increased in PTB while IL-10 was also increased in ETB (p = 0.003), all in comparison with EC. M. tuberculosis-stimulated IL-6 (p = 0.003) was lowered in ETB as compared with EC. SOCS1 mRNA expression in M. tuberculosis stimulated PBMCs levels in moderately advanced PTB (p = 0.022), far advanced (p = 0.014) PTB, and severe ETB (p = 0.009) were raised as compared with EC. On the other hand, SOCS1 mRNA titers were reduced in less severe ETB, in comparison with severe ETB (p = 0.027) and far advanced PTB (p = 0.016). SOCS3 mRNA accumulation was reduced in far advanced PTB (p = 0.007) and FoxP3 mRNA expression was increased in less severe ETB as compared with EC (p = 0.017). CONCLUSIONS: The lowered SOCS1 mRNA levels in patients with less severe extra-pulmonary TB as compared to those with more severe ETB and PTB may lead to elevated IFN-γ pathway gene expression in the latter group. As localized ETB has shown to be associated with more effective Th1 immunity and adaptive responses, this suggests a role for SOCS1 in determining disease outcome in extra-pulmonary TB.
Assuntos
Fatores de Transcrição Forkhead/genética , Interleucina-6/metabolismo , Mycobacterium tuberculosis , Proteínas Supressoras da Sinalização de Citocina/genética , Tuberculose/genética , Tuberculose/metabolismo , Citocinas/metabolismo , Regulação da Expressão Gênica , Humanos , Leucócitos Mononucleares/imunologia , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/microbiologia , Mycobacterium tuberculosis/imunologia , Índice de Gravidade de Doença , Proteína 1 Supressora da Sinalização de Citocina , Proteína 3 Supressora da Sinalização de Citocinas , Tuberculose/imunologiaRESUMO
PURPOSE: Perianal fistula is one of the most common anorectal diseases in adult patients, especially men. A relationship between pyogenic perianal abscess and fistula formation is established in multiple domains. This is the first exploration of such association among patients in the country as no related study has been published in Bahrain. We expect this study to be a foundation for future protocols and evidence-based practice. METHODS: A retrospective study was conducted in Salmaniya Medical Complex of Bahrain. A total of 109 patients with a diagnosis of anal abscess were included between 2015 and 2018. Data were collected from the electronic files database used in Salmaniya Medical Complex (iSeha) as well as phone calls to the patients. Collected data were analyzed using statistical software. RESULTS: The most predominant presentation of perianal abscess was pain. Over 50% of abscesses were classified as perianal (56.9%) and among those, left-sided abscesses were more common, followed by right-, posterior-, and anterior-sited, respectively. No recurrence of abscess was recorded among 80% of patients. A fistula developed following abscess drainage in 33.9% of patients. Most fistulas (37.8%) were diagnosed within 6 months or less from abscess drainage. Posterior fistulas were the most common, followed by anterior and left-sided fistulas. CONCLUSION: The incidence of anal fistula in Bahrain after perianal abscess was 33.9%. Most of the patients who developed a fistula following pyogenic abscess drainage were males and above the age of 40 years. The most common site for fistula was posterior.
RESUMO
Background: Whole-genome sequencing (WGS) data of Mycobacterium tuberculosis (MTB) complex strains have revealed insights about genetic variants associated with drug resistance (DR). Rapid genome-based diagnostics are being sought for specific and sensitive identification of DR; however, correct prediction of resistance genotypes requires both informatics tools and understanding of available evidence. We analyzed WGS datasets from phenotypically susceptible MTB strains using MTB resistance identification software. Methods: WGS data for 1526 MTB isolates classified as phenotypically drug susceptible were downloaded from the ReSeqTB database. The TB-Profiler software was used to call Single Nucleotide Variants (SNV) associated with resistance to rifampicin (RIF), isoniazid (INH), ethambutol (EMB), pyrazinamide, fluoroquinolone (FLQ), streptomycin (STR), and aminoglycosides. The SNV were further matched against the 2021 World Health Organization (WHO) catalogue of resistance mutations. Results: Genome analysis of 1526 MTB strains susceptible to first-line drugs revealed 39 SNV associated with DR to be present in across 14 genes in 5.9% (n = 90) isolates. Further interpretation of SNV based on the WHO catalog of mutations revealed resistance that 21 (1.4%) MTB isolates were resistant to first-line (4 to RIF, 14 to INH, 3 to EMB) drugs. While, 36 (2.6%) isolates were resistant to second-line (19 to STR, 14 to FLQ, and three to capreomycin) agents. The most frequent predictive SNV were; rpoB Ser450 Leu for RIF; katG Ser315Thr, inhA Ser94Ala, fabG1-15C >T (for INH); gyrA Asp94Gly for FLQ; embB Met306 Leu for EMB; rpsL Lys43Arg for STR; and tlyA Asn236 Lys for Capreomycin. Conclusions: Our study highlights the value of WGS-based sequence data for identifying resistance in MTB. It also shows how MTB strains may be misclassified simply on phenotypic drug susceptibility testing, and that correct genome interpretation is key for correct interpretation of resistance genotypes that can be used to guide clinical treatment.