The objective of this study was to assess the performance of direct real time RT-PCR detection of SARS-CoV-2 in heated saliva samples, avoiding the RNA isolation step. Oropharyngeal and nasopharyngeal swabs together with saliva samples were obtained from 51 patients clinically diagnosed as potentially having COVID-19. Two different methods were compared: 1. RNA was extracted from 500 μl of sample using a MagNA Pure Compact Instrument with an elution volume of 50μl and 2. 700µL of saliva were heat-inactivated at 96°C for 15 minutes, and directly subjected to RT-PCR. One step real time RT-PCR was performed using 5 μl of extracted RNA or directly from 5 μl of heated sample. RT-PCR was performed targeting the SARS-CoV-2 envelope (E) gene region. Diagnostic performance was assessed using the results of the RT-PCR from nasopharyngeal and oropharyngeal swabs as the gold standard. The overall sensitivity, specificity, positive and negative predictive values were 81.08%, 92.86%, 96.77% and 65.00%, respectively when RNA extraction was included in the protocol with saliva, whereas sensitivity, specificity, positive and negative predictive values were 83.78%, 92.86%, 68.42% and 96.88%, respectively, for the heat-inactivation protocol. However, when the analysis was performed exclusively on saliva samples with a limited time from the onset of symptoms (<9 days, N=28), these values were 90%, 87.5%, 44% and 98.75% for the heat-inactivation protocol. The study showed that RT-PCR can be performed using saliva in an RNA extraction free protocol, showing good sensitivity and specificity.
We report a case of spontaneous abortion associated with Zika virus infection in a pregnant woman who traveled from Spain to the Dominican Republic and developed a rash. Maternal Zika viremia persisted at least 31 days after onset of symptoms and 21 days after uterine evacuation.
Background: Leptospirosis is an important zoonosis worldwide, nevertheless is often poor recognized in non tropical settings. In Thailand is becoming an emerging disease and Chiang Mai could become a popular spot to acquire the disease amongst travelers. Methods: We describe three cases of imported leptospirosis undifferentiated fever after travelling to Thailand during the summer of 2015 diagnosed at two Spanish hospitals. Results: Our three patients probably acquired leptospirosis while swimming in freshwater around Chiang Mai, a Thailand's northern region with moderate incidence of leptopirosis. Travelers had normal white blood cell counts and low platelets, suggesting leptospirosis after ruling out other imported diseases such as malaria, dengue or typhoid. Conclusion: As recent findings point out, low platelets and normal white blood cell counts are clinical features that could help the clinician to suspect Leptospirosis infection. It should be always considered as a cause of fever, particularly if travelers come from a tropical country and have had contact with water or flooding, especially during rainy season.
62 Schistosomiasis in the Senegal River Basin and the role of wild rodents as reservoir hosts Stefano Catalano1, Elsa Léger1, Cheikh B. Fall2, Anna Borlase1, Mariama Sène3, Nicolas D. Diouf3, Khalilou Bâ4, Joanne P. Webster1 1Centre for Emerging, Endemic and Exotic Diseases (CEEED), Department of Pathobiology and Population Sciences, The Royal Veterinary College, University of London, Hatfield AL9 7TA, United Kingdom, scatalano@rvc.ac.uk 2Faculté de Médecine, de Pharmacie et d’Odontologie, Université Cheikh Anta Diop, Dakar, Senegal 3Unité de Formation et de Recherche (UFR) des Sciences Agronomiques, d’Aquaculture et de Technologies Alimentaires (S2ATA), Université Gaston Berger, Saint-Louis BP234, Senegal 4Centre de Biologie et de Gestion des Populations, Institut de Recherche pour le Développement, Campus ISRA-IRD Bel Air, Dakar, Senegal
Viruses are a key component of marine ecosystems, but the assessment of their global role in regulating microbial communities and the flux of carbon is precluded by a paucity of data, particularly in the deep ocean. We assessed patterns in viral abundance and production and the role of viral lysis as a driver of prokaryote mortality, from surface to bathypelagic layers, across the tropical and subtropical oceans. Viral abundance showed significant differences between oceans in the epipelagic and mesopelagic, but not in the bathypelagic, and decreased with depth, with an average power-law scaling exponent of -1.03 km-1 from an average of 7.76 × 106 viruses ml-1 in the epipelagic to 0.62 × 106 viruses ml-1 in the bathypelagic layer with an average integrated (0 to 4000 m) viral stock of about 0.004 to 0.044 g C m-2, half of which is found below 775 m. Lysogenic viral production was higher than lytic viral production in surface waters, whereas the opposite was found in the bathypelagic, where prokaryotic mortality due to viruses was estimated to be 60 times higher than grazing. Free viruses had turnover times of 0.1 days in the bathypelagic, revealing that viruses in the bathypelagic are highly dynamic. On the basis of the rates of lysed prokaryotic cells, we estimated that viruses release 145 Gt C year-1 in the global tropical and subtropical oceans. The active viral processes reported here demonstrate the importance of viruses in the production of dissolved organic carbon in the dark ocean, a major pathway in carbon cycling.