Browsing by Author "Núncio, M.S."
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- Assessment of Francisella Tularensis in PortugalPublication . Lopes de Carvalho, I.; Carvalho, C.L.; Kingry, L.R.; Zé-Zé, Líbia; Petersen, J.M.; Núncio, M.S.
- Biological toxins detection: a rapid diagnosis in an emergency responsePublication . Lopes de Carvalho, I.; Cordeiro, R.; Saraiva, M.; Cunha, I.C.; Pelerito, A.; Núncio, M.S.Toxins are chemical substances of biological origin, and they can be considered chemical or biological warfare agents. Four toxins are included in the list of bioterrorism agents: botulinum toxin (BoNT), saxitocin, ricin, and staphylococcal enterotoxin B. BoNT is included in Category A, while the other 3 are considered Category B. Botulism is a potentially fatal disease caused solely by the action of serologically distinct neurotoxins (BoNT/A, /B, /C, /D, /E, /F/ or /G) that prevent acetylcholine release at neuromuscular junctions, resulting in paralysis. The Emergency Response and Biopreparedness Unit is the Portuguese national reference laboratory for biological events or catastrophes and has skilled professionals, know-how, Biosafety Level (BSL)-3 facilities, capacity to work 24 hours per day, 7 days per week, and trained human resources to increase lab capacity in emergency situations. The laboratory diagnosis capacity includes the detection of bacteria, viruses, and toxins that are considered bioterrorism agents, using microbiology, immunology, and molecular biology techniques. Participation in European projects such as EquaTox allowed the upgrade of biosafety procedures and technical skills and the implementation of the best techniques to detect the biological toxins that can be used as biological weapons.
- Birds as reservoirs for Borrelia burgdorferi s.l. in Western Europe: circulation of B. turdi and other genospecies in bird-tick cycles in PortugalPublication . Norte, A.C.; Ramos, J.A.; Gern, L.; Núncio, M.S.; Lopes de Carvalho, I.Birds as reservoirs for Borrelia burgdorferi s.l. in Western Europe: circulation of B. turdi and other genospecies in bird-tick cycles in Portugal. Norte AC, Ramos JA, Gern L, Núncio MS, Lopes de Carvalho I. SourceInstitute of Marine Research IMAR/CMA, Department of Life Sciences, University of Coimbra, Apartado 3046, 3001-401 Coimbra, Portugal. Center for Vector and Infectious Diseases Research, National Health Institute Doutor Ricardo Jorge, Lisbon, Portugal. Laboratory of Eco-Epidemiology of Parasites, Institute of Biology, University of Neuchâtel, Neuchâtel, Switzerland. Abstract Birds are important in the ecology of Borrelia burgdorferi sensu lato (s.l.) because they are important hosts for vector tick immature stages and are known reservoirs for some Borrelia genospecies. The aim of our study was to assess the role of common passerine bird species as reservoirs for B. burgdorferi s.l. in Western Europe. We surveyed birds in enzootic areas in Portugal, where no information is available for birds as reservoirs for this aetiologic agent and where B. lusitaniae, for which few reservoirs have been identified, is the dominant genospecies. Twenty-three birds (2.9%), including Turdus merula, T. philomelos, Parus major and Fringilla coelebs harboured infected ticks, but only Turdus sp. harboured infected tick larvae. In one study area, although B. lusitaniae was dominant in questing Ixodes ricinus, no ticks feeding on birds were infected with this genospecies, and B. valaisiana was the dominant genospecies in I. ricinus larvae feeding on birds. In the other area ticks collected from birds were mainly I. frontalis which were infected with B. turdi. Two skin biopsies (4.2%) from two T. merula were positive, one for B. valaisiana and the other for B. turdi. This is the first report for B. turdi in Western Europe. © 2012 Society for Applied Microbiology and Blackwell Publishing Ltd. PMID:22882497[PubMed - as supplied by publisher]
- Blackbirds Turdus merula as competent reservoirs for Borrelia turdi and Borrelia valaisiana in Portugal: evidence from a xenodiagnostic experimentPublication . Norte, A.C.; Lopes de Carvalho, I.; Núncio, M.S.; Ramos, J.A.; Gern, L.To confirm that thrushes, such as blackbirds Turdus merula, play a role as reservoir for some Borrelia genospecies, we performed a xenodiagnostic experiment with blackbirds captured in a mixed wood located in Western Portugal where Borrelia turdi, an uncommon genospecies in Europe, was the most prevalent genospecies associated with birds. Two out of five birds harboured B. turdi infected Ixodes frontalis at the time of capture. Four out of five birds transmitted spirochaetes to Ixodes ricinus xenodiagnostic ticks: two birds transmitted Borrelia valaisiana to 25.7% and 10.5% of ticks, and two transmitted B. turdi to 6.4% and 5.4% of ticks. Our results showed that blackbirds transmit B. valaisiana and B. turdi to I. ricinus feeding larvae, acting as reservoir hosts for these genospecies in nature.
- Borrelia hispanica in Ornithodoros erraticus, PortugalPublication . Palma, Mariana; Lopes de Carvalho, I.; Figueiredo, M.; Amaro, F.; Boinas, F.; Cutler, S.J.; Núncio, M.S.Clin Microbiol Infect ABSTRACT: Tick-borne relapsing fever (TBRF) is a spirochetal infection caused by the genus Borrelia. The disease is distributed in the Old and New World with many different species reported. In Europe, TBRF is caused by B. hispanica transmitted to man by Ornithodoros erraticus, a soft tick usually found in old premises to shelter pig herds. In Portugal, the first human case of TBRF was reported in 1942 but since the beginning of the 1960s, the disease has rarely been described and seems to either have disappeared or have been undiagnosed. Therefore, in 2009 a survey was undertaken to evaluate the presence of the tick in this type of premises and to evaluate its role as a reservoir of Borrelia. The work was carried out where the ticks were previously reported in the Alentejo and Algarve regions. Of 63 pigpens surveyed, O. erraticus was collected from 19% (n = 12) of these pigpens using CO(2) traps. To evaluate potential Borrelia hosts, both pigs (n = 25) and small rodents (n = 10) inhabiting these pigpens were surveyed for Borrelia presence, by whole blood PCR and/or tissue culture, respectively. All results for pigs and rodents were negative for the presence of B. hispanica. PCR assays targeting the 16S rRNA gene and intergenic spacer region of Borrelia were used. Sequence analysis of the positive samples confirmed the presence of B. hispanica in 2.2% (n = 5) of ticks from a pigpen in Alentejo. These results confirm natural, but albeit low, persistence of this agent in Portugal.
- Borrelia wingmen: dispersal and maintenance of Borrelia burgdorferi s.l. by birdsPublication . Norte, A. C.; Ramos, J.A.; Araújo, P.M.; da Silva, L.P.; Heylen, D.; Costantini, D.; Eens, M.; Núncio, M.S.; Lopes de Carvalho, I.Lyme borreliosis, caused by Borrelia burgdorferi s.l., is the most prevalent vector-borne disease of moderate climates of the northern hemisfere. In Portugal, several Borrelia genospecies are present in questing ticks, which have different associations with vertebrate reservoir hosts and Lyme borreliosis etiology. To better understand disease risk it is necessary to evaluate the relationships among Borrelia genospecies, their tick vectors and vertebrate reservoir hosts.
- Borreliose de Lyme: descrição clinica e laboratorial em doentes portuguesesPublication . Lopes de Carvalho, I.; Luz, T.; Gomes, M.S.; Parreira, P.; Núncio, M.S.Borrelia burgdorferi sensu lato (s.l.) é o agente etiológico da borreliose de Lyme (BL), uma das doenças transmitidas por carraças com maior impacto em Portugal. No Homem, B. lusitaniae está inequivocamente associada a causar doença no Homem, com dois casos clínicos reportados.
- A comparative test of ixodid tick identification by a network of European researchersPublication . Estrada-Peña, A.; D'Amico, G.; Palomar, A.M.; Dupraz, M.; Fonville, M.; Heylen, D.; Habela, M.A.; Hornok, S.; Lempereur, L.; Madder, M.; Núncio, M.S.; Otranto, D.; Pfaffle, M.; Plantard, O.; Santos-Silva, M.M.; Sprong, H.; Vatansever, Z.; Vial, L.; Mihalca, A.D.This study reports the results of a comparative test of identification of ticks occurring in Western Europe and Northern Africa. A total of 14 laboratories were voluntarily enrolled in the test. Each participant received between 22 and 25 specimens of adult and nymphal ticks of 11 species: Dermacentor marginatus, D. reticulatus, Haemaphysalis punctata, Hyalomma lusitanicum, Hy. marginatum, Ixodes ricinus, I. hexagonus, Rhipicephalus annulatus, R. bursa, R. rossicus, and/or R. sanguineus s.l. Ticks were morphologically identified by three of the co-authors and the identification confirmed by a fourth co-author who used molecular methods based on several genes. Then ticks were randomly selected and blindly distributed among participants, together with a questionnaire. Only specimens collected while questing and, if possible, in the same survey, were circulated. Because of the random nature of the test, a participant could receive several specimens of the same species. Species in the different genera had variable misidentification rates (MR) of 7% (Dermacentor), 14% (Ixodes), 19% (Haemaphysalis), 36% (Hyalomma), and 54% (Rhipicephalus). Within genera, the MR was also variable ranging from 5.4% for I. ricinus or 7.4% for D. marginatus or D. reticulatus to 100% for R. rossicus. The test provided a total misidentification rate of 29.6% of the species of ticks. There are no significant differences in MR according to the sex of the tick. Participants were requested to perform a second round of identifications on the same set of ticks, using only purposely prepared keys (without illustrations), circulated to the enrolled participants, including 2 species of the genus Dermacentor, 8 of Haemaphysalis, 10 of Hyalomma, 23 of Ixodes, and 6 of Rhipicephalus. The average MR in the second round was 28%: 0% (Dermacentor), 33% (Haemaphysalis), 30% (Hyalomma) 18% (Ixodes), and 50% (Rhipicephalus). Species which are not reported in the countries of a participating laboratory had always highest MR, i.e. purely Mediterranean species had highest MR by laboratories in Central and Northern Europe. Participants expressed their concerns about a correct identification for almost 50% of the ticks of the genera Hyalomma and Rhipicephalus. The results revealed less than total confidence in identifying the most prominent species of ticks in the Western Palearctic, and underpin the need for reference libraries for specialists involved in this task. Results also showed that a combination of certain genes may adequately identify the target species of ticks.
- Dengue outbreak in Madeira Island (Portugal). Blood safety measures.Publication . Escoval, M.A.; Sousa, G.; Freitas, B.; Sousa, A.P.; Alves, M.J.; Núncio, M.S.; Mansinho, K.; Carmona, R.
- 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.