Browsing by Author "Silva, C."
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- Country-wide surveillance of norovirus outbreaks in the Portuguese Army, 2015-2017Publication . Lopes-João, A.; Mesquita, J.R.; de Sousa, R.; Oleastro, M.; Silva, C.; Penha-Gonçalves, C.; Nascimento, M.S.J.INTRODUCTION: Gastrointestinal infections are among the most common foodborne and waterborne diseases in military populations, with direct implications in operational efficiency and force readiness. Through the surveillance system of reportable acute gastrointestinal illness in the Portuguese Army, four norovirus outbreaks were identified between October 2015 and October 2017 in mainland Portugal and the Azores archipelago. The present study documents the epidemiological, clinical and laboratory investigations of these norovirus outbreaks. METHODS: Cases were investigated and epidemiological questionnaires were distributed to all soldiers in each military setting where the outbreaks occurred. Stool samples from soldiers with acute gastroenteritis illness were collected and screened for common enteropathogenic agents. Food and water samples served on the settings were also collected for microbiological investigation. Norovirus-positive samples were further characterised by sequence analysis using a public automated genotyping tool. RESULTS: The four outbreaks affected a total of 99 soldiers among the 618 stationed on base units and in a military exercise. A total of 27 soldiers provided a stool sample, of which 20 were positive for norovirus by real-time PCR. Phylogenetic analysis showed that the noroviruses involved were all genogroup II, namely GII.17, GII.Pe-GII.4 Sydney 2012, GII.P2-GII.2 and GII.P16-GII.2. Of note, 30 soldiers had to receive treatment at the military hospital due to severity of symptoms. CONCLUSION: In this short, two-year surveillance period, a total of four norovirus gastroenteritis outbreaks were detected in the Portuguese Army which caused a considerable morbidity, showing once again the impact of norovirus on Army effectiveness and force readiness.
- Development of a Novel Targeted Panel Sequencing Assay to Identify Patients with Familial HypercholesterolemiaPublication . Medeiros, A.M.; Silva, C.; Vieira, Luís; Bourbon, M.Introduction: Familial hypercholesterolemia (FH) is a common autosomal dominant disorder of lipid metabolism. Genetic diagnosis of FH currently includes the study of LDLR, APOB (2 fragments of exons 26 and 29) and PCSK9, by PCR plus Sanger sequencing, although other techniques such as pyrosequencing have already been used in our lab to study LDLR and APOB genes. However, in our cohort, like in most populations, about 55% of patients with clinical diagnosis of FH do not present an identifiable mutation in any of these genes using these current techniques. Based on our previous studies we speculate that up to 10% of our clinical FH patients without an identifiable mutation may have an unknown functional mutation in APOB gene, outside the LDL-binding region; also mutations in other genes like LDLRAP1, APOE or LIPA are expected in other 2-5% patients. Here we present the preliminary results of the development of a novel targeted panel sequencing (TPS) approach with all the mentioned 6 genes, for patient identification improvement.
- Molecular and epidemiologic study of Clostridium difficile reveals unusual heterogeneity in clinical strains circulating in different regions in PortugalPublication . Santos, A.; Isidro, J.; Silva, C.; Boaventura, L.; Diogo, J.; Faustino, A.; Toscano, C.; Oleastro, M.Clostridium difficile infection (CDI) represents a great healthcare burden in developed countries. The emergence of the epidemic PCR ribotype (RT) 027 and its acquired fluoroquinolones resistance have accentuated the need for an active surveillance of CDI. Here we report the first countrywide study of CDI in Portugal with the characterization of 498 C. difficile clinical isolates from 20 hospitals in four regions in Portugal regarding RT, virulence factors and antimicrobial susceptibility. We identified 96 RTs with marked variations between and within regions, as only six RTs appeared in all four regions. RT027 was the most frequent RT overall (18.5%) and among healthcare facility-associated isolates (19.6%), while RT014 was the most common among community-associated isolates (12%). The north showed a high RT diversity among isolates and a low moxifloxacin (MXF) resistance rate (11.9%), being the only region in which RT027 was not predominant. In contrast, the isolates from the centre presented the highest RT027 frequency, and 53.4% were resistant to MXF. Overall, MXF resistance (33.2%) was associated (p <0.001) with the presence of binary toxin genes and mutations in tcdC regardless of the RT. Both traits appeared in almost 30% of the strains. RT027 showed a reduced susceptibility to metronidazole (p <0.01), and RT126 had higher minimum inhibitory concentrations to vancomycin (p = 0.03) compared to other RTs. The present study highlights an unusual heterogeneity of RTs in Portugal, with a high frequency of hypervirulent RTs and the emergence of virulence factors in non-027 RTs, emphasizing the need for a surveillance system for CDI in Portugal.
- Tonsillar ulceration as manifestation of disseminated African histoplasmosis in an immunocompetent Portuguese hostPublication . Cardoso, L.; Silva, C.; Marques, N.; Veríssimo, CristinaHistoplasmosis is a systemic mycosis caused by Histoplasma capsulatum. Rare in Europe but endemic in some regions of Brazil, United States, Africa and Asia. Most of the cases are asymptomatic. Disseminated form is defined by the presence of an extra-pulmonary focus, particularly associated with immunosuppression. We report a case of an unilateral persisted tonsillar ulceration, in an immunocompetent Portuguese host, as manifestation of disseminated African histoplasmosis 45 years later after living 3 years in Africa.
- Untreated sewage contamination of beach sand from a leaking underground sewage systemPublication . Brandão, J.; Albergaria, I.; Albuquerque, J.; José, S.; Grossinho, J.; Ferreira, F.C.; Raposo, A.; Rodrigues, R.; Silva, C.; Jordao, L.; Sousa, M.; Rebelo, M.H.; Veríssimo, C.; Sabino, R.; Amaro, T.; Cardoso, F.; Patrão-Costa, M.; Solo-Gabriele, H.Thirty people (mostly children) experienced an episode of skin rash days after a sand sifting beach operation at Porto Pim Beach in Faial, Azores during June 2019. An environmental and epidemiologic investigation was conducted to identify the cause of the outbreak of skin rash. The epidemiologic investigation found that some of the patients experiencing symptoms had never entered the beach water. During the pollution period and throughout the epidemiologic investigation, faecal indicator bacteria levels (94 CFU/100 ml for intestinal enterococci and 61 CFU/100 ml for Escherichia coli) in water remained under the limits used for the ninety-five percentile calculation of an Excellent coastal and transitional bathing water defined in the Portuguese Legislation (100 CFU/100 ml for intestinal enterococci and 250 CFU/100 ml for Escherichia coli). Thus sand contact was considered as a likely primary exposure route. Sand microbiological analysis for faecal indicator organisms and electron microscopy strongly suggested faecal contamination. Chemical analysis of the sand also revealed a concomitant substance compatible with sodium-hypochlorite as analysed using gas chromatography and subsequently confirmed by free chlorine analysis. Inspection of the toilet facilities and sewage disposal system revealed a leaking sewage distribution box. Collectively, results suggest that the cause of the outbreak was the leaking underground sewage distribution box that serviced the beach toilet facilities (40 m from beach), where sodium-hypochlorite was used for cleaning and disinfection. This sewage then contaminated the surficial sands to which beach goers were exposed. Chlorine being an irritant substance, was believed to have been the cause of the symptoms given the sudden presentation and dissipation of skin rashes. No gastro-intestinal illness was reported during this episode and during the following 30 days. Like water, beach sand should also be monitored for safety, especially for areas serviced by aged infrastructure.