Browsing by Author "Lopes de Carvalho, Isabel"
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- Borrelia lusitaniae and Lyme borreliosis in Portugal: a contribution to the study of an emerging bacterial zoonosis with an impact on public healthPublication . Lopes de Carvalho, Isabel; Núncio, Maria Sofia; Carolino, M. ManuelaLyme borreliosis, is a tick-borne disease caused by Borrelia burgdorferi sensu lato, that is considered an emerging disease in some regions of the world, namely in Portugal. The B. burgdorferi s. l. complex includes 16 different species that are transmitted to the vertebrate host by the tick vector. The principal vector in Europe is Ixodes ricinus. LB is a multisystem disease involving many organs such as the skin, the nervous system, the joints, and the heart. The main goal of this project is to examine specific biological and molecular aspects of B. lusitaniae. The aims of this dissertation are divided into two main topics: Human infection and the eco-epidemiological study of B. burgdorferi s.l. in Portugal. Although LB is a mandatorily notifiable disease in Portugal, the evaluation of CEVDI/INSA data concerning human cases and the number of notified cases shows that this disease is clearly underreported in Portugal. In the period of 1999-2004, the estimated incidence was 0.4 per 100 000 inhabitants, which is relatively low when compared with some endemic countries. In this work it was reported an isolation of B. lusitaniae from a human patient presenting with a vasculitis-like syndrome that confirm the patogenicity of this genospecies. This clinical report supports also the hypothesis that the clinical manifestations associated with infection by B. lusitaniae include some clinical symptoms until this moment considered unspecific for LB. In a prospective study, twelve patients with clinical diagnostic of LB were analysed and enabled the first detection of B. afzelii DNA in a patient with neurological symptoms. A survey of ixodid ticks collected in Madeira Island and southern region revealed that both are hotspot regions for the presence of B. lusitaniae, however other Borrelia genospecies were detected in Madeira Island. Moreover, Ixodes ricinus species was confirmed as the principal vector of this zoonosis in Portugal. Other species such as Dermacentor marginatus were found to contain Borrelia DNA, but the ability of this tick to transmit B. burgdorferi is unknown. The sequences analysis of the isolates obtained from ticks from the southern region reveal that some recombinants strains are present which could indicate that an intersection in the allelic profiles of the B. lusitaniae populations exists. In this dissertation is also described the first report of dual infections of Rickettsia helvetica, R. monacensis and R. slovaca, each of which infected with B. lusitaniae, highlighting the increased likelihood of infection by multiple agents to humans. Concerning the study on migratory shorebirds the detection of B. garinii DNA was observed in three different genera (black-tailed godwits Limosa l. limosa, Icelandic black-tailed godwit Limosa l. islandica and little stints Calidris minuta) and also Francisella tularensis subsp. holarctica DNA in a little stint. The studies conducted in animal species prove the involvement of the small mammals, Apodemus sylvaticus, as a potential reservoir of B. lusitaniae with the first isolate from this animal species. Seropositive samples were obtained from M. spretus and R. rattus species. Phylogenetic analyses grouped this new isolate near other B. lusitaniae strains isolated within this dissertation and most closely aligned to the North African clade. Furthermore the importance of lizards (Teira dugessi) in the maintenance of B. burgdorferi s.l. was confirmed. Potential B. valaisiana isolation from lizard tissues and detection on parasitizing ticks was reported for the first time, but this observation needs conformation. B. lusitaniae DNA was also detected in lizard tissues and in ticks that are collected from them. However, the sequence data from lizards’ isolation suggest the co-existence of B. lusitaniae. This data indicates that there may exist a sylvatic cycle specific to the B. lusitaniae, maintained by a variety of hosts and reservoirs. Many aspects introduced and explored in this work will require more detailed investigations. However, this dissertation contributes to clarify some important epidemiological aspects of the clinical and laboratorial diagnosis of LB, a disease with impact in public health in Portugal.
- Characterization through multilocus sequence analysis of Borrelia turdi isolates from PortugalPublication . Norte, Ana Cláudia; Araújo, Pedro Miguel; Pascoal da Silva, Luís; Tenreiro, Paulo Quadros; Ramos, Jaime A; Núncio, Maria Sofia; Zé-Zé, Líbia; Lopes de Carvalho, IsabelBorrelia turdi is a spirochete from the Borrelia burgdorferi complex, first reported in Japan, that has been increasingly detected in Europe. This genospecies is mostly associated with avian hosts and their ornithophilic ticks such as Ixodes frontalis. In this study, we isolated B. turdi from five I. frontalis feeding on Turdus merula, Turdus philomelos, Parus major and Troglodytes troglodytes, and one Ixodes ricinus feeding on a T. merula in Portugal. These isolates were genetically characterised according to their 5S-23S rRNA intergenic spacer, 16S rRNA and through typing of seven housekeeping genes (multilocus sequence typing). Multilocus sequence analyses revealed that the strains isolated in our study, although belonging to B. turdi genospecies, are not identical to the B. turdi reference strain Ya501. Instead, our strains are separated into a clear defined group, suggesting that the European samples diverged genetically from the strain originally detected in Japan. Population analysis of 5S-23S rRNA sequences can further resolve subpopulations within B. turdi, but more samples from a large geographical scale and host range would be needed to assess potential phylogeographical patterns within this genospecies.
- Demographic and Clinical Characteristics of Mpox Patients Attending an STD Clinic in LisbonPublication . Cid Brito, Margarida; Nuncio, M.S.; Lopes de Carvalho, Isabel; Cordeiro, Rita; Pelerito, AnaMpox 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.
- Detection of Borrelia lusitaniae, Rickettsia sp. IRS3, Rickettsia monacensis and Anaplasma phagocytophilum in Ixodes ricinus collected in Madeira Island, PortugalPublication . Lopes de Carvalho, Isabel; Milhano, N.; Santos, A.S.; Almeida, V.; Barros, S.C.; De Sousa, R.; Núncio, M.S.A total of 300 Ixodes ricinus ticks were tested by polymerase chain reaction (PCR) for the presence of Borrelia spp., Rickettsia spp., and Anaplasma phagocytophilum. Sequence analysis demonstrated 8 (2.7%) ticks infected with B. lusitaniae, 60 (20%) with Rickettsia spp., and 1 (0.3%) with A. phagocytophilum. Seven (2.3%) ticks were coinfected with B. lusitaniae and Rickettsia spp., 2 (0.6%) with R. monacensis, and 5 (1.7%) with Rickettsia sp. IRS3. The results of this study suggest simultaneous transmission of multiple tick-borne agents on Madeira Island, Portugal.
- Detection of mpox using polymerase chain reaction from the skin and oropharynx over the course of infection: A prospective studyPublication . Correia, Catarina; Alpalhão, M,; de Sousa, D,; Vieitez-Frade, J.; Pelerito, Ana; Cordeiro, Rita; Lopes de Carvalho, Isabel; Núncio, MS; Ferreira, J,; Filipe, P.To the Editor: Since early May 2022, 86,746 mpox virus (MPV) infections have been reported worldwide.1,2 However, its in vivo viral kinetics and infectivity remain unclear.3 We conducted a prospective observational study to determine how long MPV remains detectable in skin lesions and the oropharynx. (...)
- Detection of pathogenic microorganisms in ticks collected from wild boars (Sus scrofa) in a recreational park in PortugalPublication . Guerreiro-Nunes, Andreia; Sousa, Rita de; Núncio, Maria Sofia; Norte, Ana Cláudia; Lopes de Carvalho, Isabel[Extract] The Tapada Nacional de Mafra is a Portuguese hunting ground located in the Lisbon district, regularly visited by the public for tourism, environmental education and hunting activities. Its forest consists of an enormous plant diversity with almost 100 plants identified, and with the maritime pine (Pinus pinaster), the stone pine (Pinus pinea), and the cork oak (Quercus suber) being especially abundant (Norte et al. 2012). Furthermore, mammal species such as the wild boar (Sus scrofa, are frequently sighted in close proximity to human trails. These animals are important reproduction hosts for ticks and may play a role in the transmission of tick-borne pathogens. Ticks are vectors of several infectious agents, and consequently, their parasitic relationship with humans can cause various diseases of public health importance. The identification of those pathogens in circulation in different geographic areas contributes to a better understanding of the epidemiology of tick-related diseases, such as Lyme borreliosis, relapsing fever (RF), rickettsioses and tularemia. [...]
- Detection of Rickettsia in ticks using loop-mediated isothermal amplification (LAMP)Publication . Lansdell, Samantha; Hassan, Marwa M.; La Ragione, Roberto; Betson, Martha; Nuncio, MS; Lopes de Carvalho, Isabel; Zé-Zé, Líbia; de Sousa, Rita; Cutler, Sally; Davis, Joshua S.Objectives: The objective of the study was to develop a Loop-mediated Isothermal Amplification (LAMP) assay for screening of Rickettsia species circulating in ticks using the citrate synthase gene (gltA). The LAMP assay employed portable visualisation methods, making the assay more field-suitable. Furthermore, prior methods have not used gltA as the target, despite proven success in Polymerase Chain Reaction (PCR) methods. Methods: Using an alignment of 72 DNA sequences (comprised of 21 Rickettsia species) from GenBank we designed a novel set of gltA LAMP primers. Evaluation used DNA from 12 Rickettsia species as positive controls (extracted from cultures or naturally infected ticks) alongside a panel of negative controls representing different bacterial species. Subsequently this assay was used to screen 295 Ixodes ricinus and 24 I. hexagonus ticks collected from the UK (including northern and southern England and northern Scotland). Results: LAMP successfully detected 11 out of 12 (91.7%) Rickettsia species, excluding Rickettsia akari. Among 319 ticks collected in the UK, three were positive for Rickettsia (0.9%). All three positives were I. ricinus ticks, while none of the 24 I. hexagonus ticks were positive. Results were confirmed using a published PCR method. Sanger sequencing of PCR amplicons generated for each positive tick showed that they were all R. helvetica. Conclusions: This study introduces a novel field-applicable LAMP protocol for efficient Rickettsia screening in ticks to better assess its prevalence and consequent health risks. Furthermore, this assay has proven suitability for rickettsial detection in I. ricinus ticks, which has been reported as unsuccessful in previous European studies.
- Diversity of microorganisms in Hyalomma aegyptium collected from spur-thighed tortoise (Testudo graeca) in North Africa and AnatoliaPublication . Norte, Ana Cláudia; Harris, David James; Silveira, Diogo; Nunes, Carolina Saramago; Núncio, Maria Sofia; Martínez, Eva Graciá; Giménez, Andrés; de Sousa, Rita; Lopes de Carvalho, Isabel; Perera, AnaTicks carry a diverse community of microorganisms including non-pathogenic symbionts, commensals, and pathogens, such as viruses, bacteria, protozoans, and fungi. The assessment of tick-borne microorganisms (TBM) in tortoises and their ticks is essential to understand their eco-epidemiology, and to map and monitor potential pathogens to humans and other animals. The aim of this study was to characterize the diversity of microorganisms found in ticks collected from the spur-thighed tortoise (Testudo graeca) in North Africa and Anatolia. Ticks feeding on wild T. graeca were collected, and pathogens were screened by polymerase chain reaction using group-specific primers. In total, 131 adult Hyalomma aegyptium ticks were collected from 92 T. graeca in Morocco (n = 48), Tunisia (n = 2), Algeria (n = 70), and Turkey (n = 11). Bacteria and protozoa detected included Hemolivia mauritanica (22.9%), Midichloria mitochondrii (11.4%), relapsing-fever borreliae (8.4%), Ehrlichia spp. (7.6%), Rickettsia spp. (3.4%), Borrelia burgdorferi s.l. (0.9%), Francisella spp. (0.9%), and Wolbachia spp. (0.8%). The characterization of Rickettsia included R. sibirica mongolitimonae (Algeria), R. aeschlimannii (Turkey), and R.africae (Morocco). Hemolivia mauritanica and Ehrlichia spp. prevalence varied significantly with the sampling region/country. We did not detect significant associations in microorganism presence within ticks, nor between microorganism presence and tick mitochondrial DNA haplogroups. This is the first report of Francisella persica-like, relapsing fever borreliae, M. mitochondrii, and Wolbachia spp. in H. aegyptium ticks collected from wild hosts from the South and Eastern Mediterranean region, and of R. sibirica mongolitimonae and R. africae in H. aegyptium from Algeria and Morocco, respectively. Given that T. graeca is a common species in commercial and non-commercial pet trade, the evaluation of the role of this species and its ticks as hosts for TBM is particularly relevant for public health.
- Doenças transmissíveis por carraças com importância em Portugal: diagnósticoPublication . Lopes de Carvalho, Isabel
- Ebolavirus outbreak in West Africa: Portuguese laboratory response overviewPublication . Cordeiro, Rita; Pelerito, Ana; Lopes de Carvalho, Isabel; Núncio, SofiaThe Ebola outbreak in West Africa was the largest and most complex outbreak since the virus was discovered in 1976. First cases were notified in March of 2014 and currently cases are still being reported in the affected countries. To respond to the epidemic of Ebola virus, Portugal created an coordination committee where the National Institute of Health, through the Emergency Response and Biopreparedness Unit (UREB), participated integrating the “Platform Response to Ebola Virus Disease”. This unit is the national reference laboratory for biological events or catastrophes and has skilled professionals, know-how, BSL-3 facilities, capacity to work 24h/7d and trained human resources to increase lab capacity in emergency situations. The laboratory diagnosis capacity includes the detection of bacteria, virus and toxins, which are considered bioterrorism agents, using Microbiology, Immunology and Molecular Biology techniques. elopment of national guidelines and establish an agreement with European reference BSL-4 laboratories for additional tests.
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