{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,7,20]],"date-time":"2026-07-20T18:40:19Z","timestamp":1784572819554,"version":"3.55.0"},"reference-count":32,"publisher":"MDPI AG","issue":"8","license":[{"start":{"date-parts":[[2023,7,28]],"date-time":"2023-07-28T00:00:00Z","timestamp":1690502400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"Istituto Zooprofilattico Sperimentale del Mezzogiorno"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Pathogens"],"abstract":"<jats:p>Nocardia crassostreae is a novel pathogen responsible for infections in oysters (Crassostrea gigas) and mussels (Mytilus galloprovincialis). N. crassostreae is also responsible for nocardiosis both in immunocompetent and immunocompromised patients. We investigated N. crassostreae DNA in mussels grown in marine sites of the Mediterranean Sea in the Campania Region. We examined 185 mussel pooled samples by droplet digital PCR (ddPCR) and real-time quantitative PCR (qPCR), each pool composed of 10 mussels and 149 individual mussels. ddPCR detected N. crassostreae DNA in 48 mussel pooled samples and in 23 individual mussel samples. qPCR detected N. crassostreae DNA in six pooled samples and six individual mussel samples. The two molecular assays for the detection of N. crassostreae DNA showed significant differences both in the pooled and in individual samples. Our study demonstrated that ddPCR outperformed real-time qPCR for N. crassostreae DNA detection, thus confirming that ddPCR technology can identify the pathogens in many infectious diseases with high sensitivity and specificity. Furthermore, in individual mussels showing histological lesions due to N. crassostreae, the lowest copy number\/microliter detected by ddPCR of this pathogen was 0.3, which suggests that this dose could be enough to cause infections of N. crassostreae in mussels.<\/jats:p>","DOI":"10.3390\/pathogens12080994","type":"journal-article","created":{"date-parts":[[2023,7,31]],"date-time":"2023-07-31T03:30:02Z","timestamp":1690774202000},"page":"994","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Detection and Quantification of Nocardia crassostreae, an Emerging Pathogen, in Mytilus galloprovincialis in the Mediterranean Sea Using Droplet Digital PCR"],"prefix":"10.3390","volume":"12","author":[{"given":"Anna","family":"Cutarelli","sequence":"first","affiliation":[{"name":"Istituto Zooprofilattico Sperimentale del Mezzogiorno, 80055 Portici, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-1780-1990","authenticated-orcid":false,"given":"Francesca","family":"Carella","sequence":"additional","affiliation":[{"name":"Dipartimento di Biologia, Universit\u00e0 degli Studi di Napoli Federico II, 80126 Napoli, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Francesca","family":"De Falco","sequence":"additional","affiliation":[{"name":"Dipartimento di Medicina Veterinaria e Produzioni Animali, Universit\u00e0 degli Studi di Napoli Federico II, 80137 Napoli, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4769-5703","authenticated-orcid":false,"given":"Bianca","family":"Cuccaro","sequence":"additional","affiliation":[{"name":"Dipartimento di Medicina Veterinaria e Produzioni Animali, Universit\u00e0 degli Studi di Napoli Federico II, 80137 Napoli, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Fabio","family":"Di Nocera","sequence":"additional","affiliation":[{"name":"Istituto Zooprofilattico Sperimentale del Mezzogiorno, 80055 Portici, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Donatella","family":"Nava","sequence":"additional","affiliation":[{"name":"Istituto Zooprofilattico Sperimentale del Mezzogiorno, 80055 Portici, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-5953-4160","authenticated-orcid":false,"given":"Gionata","family":"De Vico","sequence":"additional","affiliation":[{"name":"Dipartimento di Biologia, Universit\u00e0 degli Studi di Napoli Federico II, 80126 Napoli, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-6210-5519","authenticated-orcid":false,"given":"Sante","family":"Roperto","sequence":"additional","affiliation":[{"name":"Dipartimento di Medicina Veterinaria e Produzioni Animali, Universit\u00e0 degli Studi di Napoli Federico II, 80137 Napoli, Italy"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,7,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"237","DOI":"10.1099\/00207713-48-1-237","article-title":"Nocardia crassostreae sp. nov., the causal agent of nocardiosis in Pacific oysters","volume":"48","author":"Friedman","year":"1998","journal-title":"Int. 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