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1.
Article in English | MEDLINE | ID: mdl-37835073

ABSTRACT

Mpox is a viral disease caused by the monkeypox virus, which marked the year of 2022 with a global outbreak. While previously considered to be a zoonosis of almost exclusive animal-to-human transmission, the current outbreak has been attributed to human-to-human transmission, particularly sexual transmission. As a new sexually transmissible disease, we studied the epidemiological and clinical features, as well as the concomitant occurrence of other sexually transmissible diseases, treatment approach, and outcome of our 291 patients, in the current outbreak. We found a total of 169 concomitant sexually transmissible infections of bacterial and viral origins, corresponding to 107 patients. Neisseria gonorrhoeae was the most common agent, particularly in the anal location. With this work, we emphasize the need for a thorough epidemiological and medical history, as well as a concomitant complete laboratorial screening for other STIs in patients with confirmed or suspected mpox.


Subject(s)
Mpox (monkeypox) , Animals , Humans , Zoonoses , Ambulatory Care Facilities , Disease Outbreaks , Demography
2.
Nat Med ; 29(10): 2509-2517, 2023 10.
Article in English | MEDLINE | ID: mdl-37696933

ABSTRACT

Pathogen genome sequencing during epidemics enhances our ability to identify and understand suspected clusters and investigate their relationships. Here, we combine genomic and epidemiological data of the 2022 mpox outbreak to better understand early viral spread, diversification and transmission dynamics. By sequencing 52% of the confirmed cases in Portugal, we identified the mpox virus sublineages with the highest impact on case numbers and fitted them into a global context, finding evidence that several international sublineages probably emerged or spread early in Portugal. We estimated a 62% infection reporting rate and that 1.3% of the population of men who have sex with men in Portugal were infected. We infer the critical role played by sexual networks and superspreader gatherings, such as sauna attendance, in the dissemination of mpox virus. Overall, our findings highlight genomic epidemiology as a tool for the real-time monitoring and control of mpox epidemics, and can guide future vaccine policy in a highly susceptible population.


Subject(s)
Mpox (monkeypox) , Sexual and Gender Minorities , Male , Humans , Portugal/epidemiology , Homosexuality, Male , Disease Outbreaks , Cluster Analysis
4.
Influenza Other Respir Viruses ; 17(3): e13121, 2023 03.
Article in English | MEDLINE | ID: mdl-36935845

ABSTRACT

Background: Information on vaccine effectiveness in a context of novel variants of concern (VOC) emergence is of key importance to inform public health policies. This study aimed to estimate a measure of comparative vaccine effectiveness between Omicron (BA.1) and Delta (B.1.617.2 and sub-lineages) VOC according to vaccination exposure (primary or booster). Methods: We developed a case-case study using data on RT-PCR SARS-CoV-2-positive cases notified in Portugal during Weeks 49-51, 2021. To obtain measure of comparative vaccine effectiveness, we compared the odds of vaccination in Omicron cases versus Delta using logistic regression adjusted for age group, sex, region, week of diagnosis, and laboratory of origin. Results: Higher odds of vaccination were observed in cases infected by Omicron VOC compared with Delta VOC cases for both complete primary vaccination (odds ratio [OR] = 2.1; 95% confidence interval [CI]: 1.8 to 2.4) and booster dose (OR = 5.2; 95% CI: 3.1 to 8.8), equivalent to reduction of vaccine effectiveness from 44.7% and 92.8%, observed against infection with Delta, to -6.0% (95% CI: 29.2% to 12.7%) and 62.7% (95% CI: 35.7% to 77.9%), observed against infection with Omicron, for complete primary vaccination and booster dose, respectively. Conclusion: Consistent reduction in vaccine-induced protection against infection with Omicron was observed. Complete primary vaccination may not be protective against SARS-CoV-2 infection in regions where Omicron variant is dominant.


Subject(s)
COVID-19 , Humans , COVID-19/prevention & control , COVID-19 Vaccines , SARS-CoV-2/genetics , Electronic Health Records
9.
Microorganisms ; 10(7)2022 Jul 20.
Article in English | MEDLINE | ID: mdl-35889189

ABSTRACT

Brucellosis, mainly caused by Brucella (B.) melitensis, is associated with a risk of chronification and relapses. Antimicrobial susceptibility testing (AST) standards for B. melitensis are not available, and the agent is not yet listed in the EUCAST breakpoint tables. CLSI recommendations for B. melitensis exist, but they do not fulfill the requirements of the ISO 20776 standard regarding the culture medium and the incubation conditions. Under the third EU Health Programme, laboratories specializing in the diagnostics of highly pathogenic bacteria in their respective countries formed a working group within a Joint Action aiming to develop a suitable method for the AST of B. melitensis. Under the supervision of EUCAST representatives, this working group adapted the CLSI M45 document to the ISO 20776 standard after testing and validation. These adaptations included the comparison of various culture media, culture conditions and AST methods. A Standard Operation Procedure was derived and an interlaboratory validation was performed in order to evaluate the method. The results showed pros and cons for both of the two methods but also indicate that it is not necessary to abandon Mueller-Hinton without additives for the AST of B. melitensis.

10.
Euro Surveill ; 27(22)2022 06.
Article in English | MEDLINE | ID: mdl-35656830

ABSTRACT

Up to 27 May 2022, Portugal has detected 96 confirmed cases of monkeypox. We describe 27 confirmed cases (median age: 33 years (range: 22-51); all males), with an earliest symptom onset date of 29 April. Almost all cases (n = 25) live in the Lisbon and Tagus Valley health region. Most cases were neither part of identified transmission chains, nor linked to travel or had contact with symptomatic persons or with animals, suggesting the possible previously undetected spread of monkeypox.


Subject(s)
Monkeypox virus , Mpox (monkeypox) , Disease Outbreaks , Humans , Male , Mpox (monkeypox)/diagnosis , Mpox (monkeypox)/epidemiology , Monkeypox virus/genetics , Portugal/epidemiology , Travel
11.
Nat Med ; 28(8): 1569-1572, 2022 08.
Article in English | MEDLINE | ID: mdl-35750157

ABSTRACT

The largest monkeypox virus (MPXV) outbreak described so far in non-endemic countries was identified in May 2022 (refs. 1-6). In this study, shotgun metagenomics allowed the rapid reconstruction and phylogenomic characterization of the first MPXV outbreak genome sequences, showing that this MPXV belongs to clade 3 and that the outbreak most likely has a single origin. Although 2022 MPXV (lineage B.1) clustered with 2018-2019 cases linked to an endemic country, it segregates in a divergent phylogenetic branch, likely reflecting continuous accelerated evolution. An in-depth mutational analysis suggests the action of host APOBEC3 in viral evolution as well as signs of potential MPXV human adaptation in ongoing microevolution. Our findings also indicate that genome sequencing may provide resolution to track the spread and transmission of this presumably slow-evolving double-stranded DNA virus.


Subject(s)
Monkeypox virus , Mpox (monkeypox) , Disease Outbreaks , Humans , Mpox (monkeypox)/epidemiology , Mpox (monkeypox)/genetics , Monkeypox virus/genetics , Phylogeny
12.
Front Microbiol ; 12: 740068, 2021.
Article in English | MEDLINE | ID: mdl-34867857

ABSTRACT

Brucellosis is an important zoonosis that is emerging in some regions of the world, gaining increased relevance with the inclusion of the causing agent Brucella spp. in the class B bioterrorism group. Until now, multi-locus VNTR Analysis (MLVA) based on 16 loci has been considered as the gold standard for Brucella typing. However, this methodology is laborious, and, with the rampant release of Brucella genomes, the transition from the traditional MLVA to whole genome sequencing (WGS)-based typing is on course. Nevertheless, in order to avoid a disruptive transition with the loss of massive genetic data obtained throughout the last decade and considering that the transition timings will vary considerably among different countries, it is important to determine WGS-based MLVA alleles of the nowadays sequenced genomes. On this regard, we aimed to evaluate the performance of a Python script that had been previously developed for the rapid in silico extraction of the MLVA alleles, by comparing it to the PCR-based MLVA procedure over 83 strains from different Brucella species. The WGS-based MLVA approach detected 95.3% of all possible 1,328 hits (83 strains×16 loci) and showed an agreement rate with the PCR-based MLVA procedure of 96.4% for MLVA-16. According to our dataset, we suggest the use of a minimal depth of coverage of ~50x and a maximum number of ~200 contigs as guiding "boundaries" for the future application of the script. In conclusion, the evaluated script seems to be a very useful and robust tool for the in silico determination of MLVA profiles of Brucella strains, allowing retrospective and prospective molecular epidemiological studies, which are important for maintaining an active epidemiological surveillance of brucellosis.

13.
PLoS One ; 15(3): e0229863, 2020.
Article in English | MEDLINE | ID: mdl-32150564

ABSTRACT

Brucellosis is an important zoonotic disease that affects both humans and animals. To date, laboratory surveillance is still essentially based on the traditional MLVA-16 methodology and the associated epidemiological information is frequently scarce. Our goal was to contribute to the improvement of Brucella spp. surveillance through the implementation of a whole genome sequencing (WGS) approach. We created a curated ready-to-use species-specific wgMLST scheme enrolling a panel of 2656 targets (http://doi.org/10.5281/zenodo.3575026) and used this schema to perform a retrospective analysis of the genetic relatedness among B. melitensis strains causing human infection in Portugal (a country where brucellosis is an endemic disease) from 2010 to 2018. The strains showed a phylogenetic clustering within genotype II (25 out of 36) and IV (4 out of 36), and shared clades with strains isolated from countries with which Portugal has intense food trading, tourism and similar eating habits, such as Spain, Italy and Greece. In addition, our results point to the identification of strong associations between B. melitensis strains, likely underlying missed "outbreaks" as 22 out of the 36 strains showed genetic linkage with others. In fact, the applied gene-by-gene approach grouped these strains into six genetic clusters each one containing putative epidemiological links. Nevertheless, more studies will be needed in order to define the appropriate range of cut-offs (probable non-static cut-offs) that best illustrate the association between genetic linkage and epidemiological information and may serve as alerts for the health authorities. The release of this freely available and scalable schema contributes to the required technological transition for laboratorial surveillance of brucellosis and will facilitate the assessment of ongoing and future outbreaks in order to prevent the transmission spread.


Subject(s)
Brucella melitensis/genetics , Brucellosis/microbiology , Genome, Bacterial , Brucellosis/epidemiology , Humans , Phylogeny , Portugal/epidemiology , Whole Genome Sequencing
14.
Toxicon X ; 4: 100017, 2019 Oct.
Article in English | MEDLINE | ID: mdl-32550574

ABSTRACT

In Portugal, the potent paralytic shellfish toxins (PSTs) have appeared irregularly since the onset of a national monitoring program for marine biotoxins in 1986. In years where high contamination levels were attained in bivalves, sporadic cases of human poisonings have been recorded, as in 1994 and 2007. The reappearance of high contamination levels led to the appearance of new cases during the autumn of 2018. This study details toxin ingestion, symptomatology and toxin elimination and metabolization in the fluids of two patients, who ingested mussels from the Portuguese southwest coast and required hospitalization due to the severity of symptoms. Toxin elimination was confirmed by ELISA in plasma and urine samples. In mussel samples, the toxin profile obtained by HPLC-FLD displayed a wide diversity of toxins, typical of Gymnodinum catenatum ingestion. However, in the urine samples, the toxin profile was reduced to B1 and dcSTX. Abundant compounds in mussels having an O-sulphate at C11, such as C1+2 and dcGTX2+3, were absent in urine. In plasma, PSTs were not detected by HPLC-FLD. Calculated toxin ingestion, resulting from consumption of an estimated 200-g portion, was in the range of 104-120 µg STX eq./kg b. w.

15.
Nat Commun ; 9(1): 4857, 2018 11 19.
Article in English | MEDLINE | ID: mdl-30451842

ABSTRACT

Anthrax is an infectious disease caused by Bacillus anthracis, a bioterrorism agent that develops resistance to clinically used antibiotics. Therefore, alternative mechanisms of action remain a challenge. Herein, we disclose deoxy glycosides responsible for specific carbohydrate-phospholipid interactions, causing phosphatidylethanolamine lamellar-to-inverted hexagonal phase transition and acting over B. anthracis and Bacillus cereus as potent and selective bactericides. Biological studies of the synthesized compound series differing in the anomeric atom, glycone configuration and deoxygenation pattern show that the latter is indeed a key modulator of efficacy and selectivity. Biomolecular simulations show no tendency to pore formation, whereas differential metabolomics and genomics rule out proteins as targets. Complete bacteria cell death in 10 min and cellular envelope disruption corroborate an effect over lipid polymorphism. Biophysical approaches show monolayer and bilayer reorganization with fast and high permeabilizing activity toward phosphatidylethanolamine membranes. Absence of bacterial resistance further supports this mechanism, triggering innovation on membrane-targeting antimicrobials.


Subject(s)
Anti-Bacterial Agents/pharmacology , Bacillus anthracis/drug effects , Bacillus cereus/drug effects , Cell Membrane/drug effects , Cell Wall/drug effects , Glycosides/pharmacology , Phosphatidylethanolamines/antagonists & inhibitors , Bacillus anthracis/chemistry , Bacillus anthracis/growth & development , Bacillus anthracis/metabolism , Bacillus cereus/chemistry , Bacillus cereus/growth & development , Bacillus cereus/metabolism , Caco-2 Cells , Carbohydrate Conformation , Cell Membrane/chemistry , Cell Membrane/metabolism , Cell Survival/drug effects , Cell Wall/chemistry , Cell Wall/metabolism , Humans , Kinetics , Lipid Bilayers/chemistry , Lipid Bilayers/metabolism , Microbial Sensitivity Tests , Microbial Viability/drug effects , Phase Transition , Phosphatidylethanolamines/chemistry , Phosphatidylethanolamines/metabolism , Structure-Activity Relationship
16.
PLoS One ; 12(7): e0179667, 2017.
Article in English | MEDLINE | ID: mdl-28692674

ABSTRACT

Brucellosis is a zoonosis that is emerging in some regions of the world. Although brucellosis is a disease of obligatory declaration and is not eradicated in Portugal, no prevalence data is available in this country. In this study, we retrospectively analyzed the data available at the Reference Laboratory at the Portuguese National Institute of Health during the past 7 years (2009-2016) in order to get insight into the epidemiological scenario of brucellosis in Portugal. A total of 2313 biological samples from patients with clinical suspicion of brucellosis were subjected to immunological techniques for laboratory diagnosis. From 2010 to 2015, a subset of 259 samples was subjected to molecular methods. According to the available data, 167 out of 2313 (7.2%) samples had positive serology for Brucella spp. and 43 out of 259 samples (16.6%) were positive for B. melitensis by real time PCR, being classified as biovar 1 and 3. This study draws attention to the importance of integrating clinical and laboratory data of human cases in order to increase the efficacy of the response measures in case of outbreaks.


Subject(s)
Brucellosis/epidemiology , Adolescent , Adult , Aged , Aged, 80 and over , Child , Female , Humans , Male , Middle Aged , Portugal/epidemiology , Retrospective Studies , Young Adult
17.
IDCases ; 3: 10-1, 2016.
Article in English | MEDLINE | ID: mdl-26962474

ABSTRACT

Burkholderia pseudomallei is a Gram-negative bacillus and the causative agent of melioidosis, a serious infection associated with high mortality rate in humans. It can be naturally found as an environmental saprophyte in soil or stagnant water, and rice paddies that predominate in regions of endemicity such as Northeast Thailand. B. pseudomallei is a Biosafety Level 3 organism due to risks of aerosolization and severe disease and is now included in formal emergency preparedness plans and guidelines issued by various authorities in the United States and Europe. Here, we report the first case of imported melioidosis in Portugal. B. pseudomallei was isolated from the patient's blood as well as from a left gluteal abscess pus. The isolate strain showed the unusual resistance profile to first-line eradication therapy trimethroprim/sulfamethoxazole. Whole genome sequencing revealed its similarity with isolates from Southeast Asia, suggesting the Thai origin of this Portuguese isolate, which is in agreement with a recent patient's travel to Thailand.

18.
Helicobacter ; 16(5): 363-72, 2011 Oct.
Article in English | MEDLINE | ID: mdl-21923682

ABSTRACT

BACKGROUND: Helicobacter pylori is mainly acquired in childhood. Although adult studies reported a high prevalence of H. pylori infection in Portugal, the actual rate in children remains unknown. This study aimed to determine the prevalence and the incidence of H. pylori infection in an asymptomatic pediatric population of the Lisbon area and to correlate prevalence with sociodemographic determinants. MATERIALS AND METHODS: Helicobacter pylori infection was determined by stool antigen test in 844 asymptomatic children (age 0-15 years; 49.4% boys). For the incidence study, H. pylori-negative children in the prevalence study were followed-up every 6 months over a 3-year period. RESULTS: The global prevalence of H. pylori infection was 31.6%, increasing with age (19.9, 37.0 and 51.5%, in age groups 0-5, 6-10, and 11-15, respectively), but was similar among genders (34.5% in boys and 28.4% in girls). Older age and attendance of nursery/kindergarten during preschool constituted independent risk factors. The overall estimated incidence was 11.6 per 100 child-years (CY). Although 47.5% of children acquired H. pylori infection before 5 years of age, the mean age of acquisition was 6.3. The incidence of infection was similar among the three age groups (11.5, 13.0, and 10.5 per 100 CY, in age groups 0-5, 6-10, and 11-15, respectively). CONCLUSIONS: The prevalence of H. pylori infection in the Portuguese pediatric population is still high. Although this study confirmed that the highest acquisition rate occurs at young age, it showed that in high-prevalence populations, older children can also acquire H. pylori infection at a rate similar to that of young children.


Subject(s)
Helicobacter Infections/epidemiology , Helicobacter pylori/isolation & purification , Adolescent , Age Factors , Child , Child, Preschool , Female , Humans , Incidence , Infant , Infant, Newborn , Male , Portugal/epidemiology , Prevalence
19.
Scand J Infect Dis ; 40(11-12): 859-66, 2008.
Article in English | MEDLINE | ID: mdl-18622806

ABSTRACT

Incidence, morbidity and mortality of bacterial meningitis in developing countries are manifold greater than those in the industrialized world. We reviewed retrospectively children with meningitis treated in the paediatric hospital of Luanda in 2004. Among the 555 children, median age 11.0 months, the leading agents were Haemophilus influenzae type b (Hib), pneumococcus, and meningococcus in 60%, 24%, and 10%, respectively. The median length of illness before admission was 7 d. 65% had convulsed. Altered level of consciousness was observed in 61% and blood haemoglobin lower than 8 g/dl in 36% of cases. Case fatality was 35% and, of survivors, 24% were left with severe neurological sequelae. Blood transfusion appeared beneficial since fatality of children with and without transfusion was 23% versus 39% (p=0.003). While awaiting large-scale vaccinations, tools to improve the prognosis of meningitis in Angola comprise generating better awareness to reduce the delay, better fluid treatment and monitoring and active use of blood transfusions.


Subject(s)
Meningitis, Haemophilus/epidemiology , Meningitis, Meningococcal/epidemiology , Meningitis, Pneumococcal/epidemiology , Angola/epidemiology , Anti-Bacterial Agents/therapeutic use , Blood Transfusion , Child, Preschool , Female , Humans , Incidence , Infant , Male , Meningitis, Haemophilus/mortality , Meningitis, Haemophilus/therapy , Meningitis, Meningococcal/mortality , Meningitis, Meningococcal/therapy , Meningitis, Pneumococcal/mortality , Meningitis, Pneumococcal/therapy , Oxygen/therapeutic use , Retrospective Studies , Treatment Outcome
20.
Am J Gastroenterol ; 101(9): 2113-22, 2006 Sep.
Article in English | MEDLINE | ID: mdl-16848806

ABSTRACT

OBJECTIVES: Both bacterial and host determinants underlying differences in histopathology and clinical outcome in H. pylori pediatric infection, as compared to adults, are still poorly documented. Pediatric studies may provide important insights on H. pylori infection immunopathogenesis, particularly in high gastric cancer risk populations. The present study concerns H. pylori genotypic diversity of isolates in children from a population with high gastric cancer risk, and its association with demographic and clinical variables, including gastroduodenal endoscopic and histopathological features. METHODS: A total of 119 subjects (mean age 10.3 yr, 1.5-18.0 yr) with H. pylori infection were studied. H. pylori vacA, cagA, and iceA genotypes were determined (PCR) in antral-obtained primary cultures; histopathological evaluation was performed in corpus, antrum, and duodenum biopsy specimens. RESULTS: cagA-, vacA s2m2, and iceA2 were the most prevalent genotypes. No association was observed between H. pylori genotypes and subject demographic and clinical variables, with the exception of a significant association between vacA s2 genotype and lower corpus inflammation score (p< 0.03). CONCLUSIONS: In this pediatric cohort, H. pylori genotype profiles were distinct from those reported in adult subjects in the same area, with a lower prevalence of the putative more virulent genotypes. Moreover, they were not associated with clinical expression of gastroduodenal disease, suggesting the potential role of host and/or environmental factors for the development of clinical disease at a later age.


Subject(s)
DNA, Bacterial/genetics , Helicobacter Infections/microbiology , Helicobacter pylori/genetics , Pyloric Antrum/microbiology , Stomach Neoplasms/complications , Adolescent , Antigens, Bacterial/genetics , Bacterial Outer Membrane Proteins/genetics , Bacterial Proteins/genetics , Biopsy , Child , Child, Preschool , Duodenum/microbiology , Duodenum/pathology , Endoscopy, Gastrointestinal , Female , Follow-Up Studies , Genotype , Helicobacter Infections/complications , Helicobacter Infections/pathology , Helicobacter pylori/isolation & purification , Humans , Infant , Male , Polymerase Chain Reaction , Prevalence , Prospective Studies , Pyloric Antrum/pathology , Risk Factors , Severity of Illness Index , Stomach Neoplasms/epidemiology , Stomach Neoplasms/pathology
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