1
|
Ahmed NHM, Ghallab A, Shaalan M, Saied M, Mohammed ES. First molecular identification and phylogenetic illustration of Sarcocystis species infection in Red Sea shortfin mako shark (Isurus oxyrinchus Rafinesque, 1810). BMC Vet Res 2024; 20:104. [PMID: 38491459 PMCID: PMC10941371 DOI: 10.1186/s12917-024-03952-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Accepted: 02/23/2024] [Indexed: 03/18/2024] Open
Abstract
BACKGROUND members of the genus Sarcocystis are intracellular obligate protozoan parasites classified within the phylum Apicomplexa and have an obligate heteroxenous life cycle involving two hosts. A more comprehensive understanding of the prevalence and geographic range of different Sarcocystis species in marine ecosystems is needed globally and nationally. Hence, the objective of this study was to document the incidence of Sarcocystis infection in sharks within the aquarium ecosystem of Egypt and to identify the species through the characterization of the SSU rDNA gene. METHODS All organs of the mako shark specimen underwent macroscopic screening to detect the existence of a Sarcocystis cyst. Ten cysts were collected from the intestine and processed separately to extract the genomic DNA. The polymerase chain reaction (PCR) was accomplished by amplifying a specific 18S ribosomal RNA (rRNA) gene fragment. Subsequently, the resulting amplicons were subjected to purification and sequencing processes. RESULTS Macroscopic examination of the mako shark intestinal wall sample revealed the presence of Sarcocystis cysts of various sizes and shapes, and sequencing of the amplicons from Sarcocystis DNA revealed a 100% nucleotide identity with the sequence of Sarcocystis tenella recorded from sheep in Iran; The mako shark sequence has been deposited in the GeneBank with the accession number OQ721979. This study presents the first scientific evidence demonstrating the presence of the Sarcocystis parasite in sharks, thereby documenting this specific marine species as a novel intermediate host in the Sarcocystis life cycle. CONCLUSIONS This is the first identification of Sarcocystis infection in sharks, and we anticipate it will be an essential study for future screenings and establishing effective management measures for this disease in aquatic ecosystems.
Collapse
Affiliation(s)
- Nahla He M Ahmed
- National Institute of Oceanography and Fisheries, NIOF, Cairo, Egypt.
| | - Ahmed Ghallab
- Natural Conservation Sector, Ministry of Environment, Cairo, Egypt
| | - Mohamed Shaalan
- Department of Pathology, Faculty of Veterinary Medicine, Cairo University, Cairo, Egypt
| | - Mahmoud Saied
- National Institute of Oceanography and Fisheries, NIOF, Cairo, Egypt
| | - Eman Sayed Mohammed
- Department of Parasitology, Faculty of Veterinary Medicine, South Valley University, Qena, 83523, Egypt
| |
Collapse
|
2
|
St. Leger J, Chen Y, Sakamaki K, Mena A, Raverty SA, Rotstein D, Grigg ME. Fatal hepatic sarcocystosis in three captive and one free-ranging pinniped. Int J Parasitol Parasites Wildl 2023; 22:249-254. [PMID: 38059179 PMCID: PMC10696305 DOI: 10.1016/j.ijppaw.2023.10.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2023] [Revised: 10/29/2023] [Accepted: 10/29/2023] [Indexed: 12/08/2023]
Abstract
Fatal hepatic sarcocystosis was diagnosed as the cause of death in four pinnipeds: two captive Hawaiian monk seals (Monachus schauinslandi), a captive, and a free-ranging California sea lion (Zalophus californianus). Based on necropsy, histopathology, electron microscopy and DNA sequencing, intralesional protozoal schizonts were determined to have caused the necrotizing hepatitis observed. Transmission Electron Microscopy (TEM) revealed schizonts similar to Sarcocystis canis in hepatocytes. PCR-DNA sequencing and phylogenetic analysis at the conserved 18S rRNA and variable ITS1 gene markers within the nuclear rRNA gene array from schizont-laden tissue established that the parasites were indistinguishable from Sarcocystis canis at the 18S rRNA locus. However, six distinct single nucleotide polymorphisms (SNPs) were resolved at ITS1 suggesting that the parasites infecting pinnipeds were distinct from S. canis, which commonly infects bears and dogs. We hypothesize that the parasite represents a novel Sarcocystis variant that we refer to as S. canis-like that infects pinnipeds. The definitive host of S. canis is enigmatic and its life cycle incomplete. These findings document a critical need to identify the life cycle(s), definitive host(s), and all susceptible marine and terrestrial intermediate hosts of S. canis and the S. canis-like variant infecting pinnipeds.
Collapse
Affiliation(s)
| | - Yang Chen
- Molecular Parasitology Section, Laboratory of Parasitic Diseases, NIAID, National Institutes of Health, Bethesda, MD, USA
| | | | | | - Stephen A. Raverty
- Animal Health Center, Ministry of Agriculture, Abbotsford, British Columbia, V3G 2M3, Canada
| | | | - Michael E. Grigg
- Molecular Parasitology Section, Laboratory of Parasitic Diseases, NIAID, National Institutes of Health, Bethesda, MD, USA
| |
Collapse
|
3
|
Bush JC, Maggi RG, Breitschwerdt EB. Viability and Desiccation Resistance of Bartonella henselae in Biological and Non-Biological Fluids: Evidence for Pathogen Environmental Stability. Pathogens 2023; 12:950. [PMID: 37513797 PMCID: PMC10383451 DOI: 10.3390/pathogens12070950] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Revised: 07/06/2023] [Accepted: 07/06/2023] [Indexed: 07/30/2023] Open
Abstract
Pathogen environmental stability is an often-neglected research priority for pathogens that are known to be vector-transmitted. Bartonella henselae, the etiologic agent of Cat Scratch Disease, has become a "pathogen of interest" in several serious human illnesses, which include neoplastic, cardiovascular, neurocognitive, and rheumatologic conditions. Survival in the flea gut and feces as well as the association with a biofilm in culture-negative endocarditis provides insight into this organism's ability to adjust to environmental extremes. The detection of B. henselae DNA in blood and tissues from marine mammals also raises questions about environmental stability and modes of pathogen transmission. We investigated the ability of B. henselae to survive in fluid matrices chosen to mimic potential environmental sources of infective materials. Feline whole blood, serum and urine, bovine milk, and physiologic saline inoculated with a laboratory strain of B. henselae San Antonio 2 were subsequently evaluated by culture and qPCR at specified time intervals. Bacterial viability was also assessed following desiccation and reconstitution of each inoculated fluid matrix. Bartonella henselae SA2 was cultured from feline urine up to 24 h after inoculation, and from blood, serum, cow's milk, and physiologic saline for up to 7 days after inoculation. Of potential medical importance, bacteria were cultured following air-desiccation of all fluid inoculates. The viability and stability of Bartonella within biological and non-biological fluids in the environment may represent a previously unrecognized source of infection for animals and human beings.
Collapse
Affiliation(s)
- Janice C Bush
- Intracellular Pathogens Research Laboratory, Department of Clinical Sciences, Comparative Medicine Institute, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27606, USA
| | - Ricardo G Maggi
- Intracellular Pathogens Research Laboratory, Department of Clinical Sciences, Comparative Medicine Institute, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27606, USA
| | - Edward B Breitschwerdt
- Intracellular Pathogens Research Laboratory, Department of Clinical Sciences, Comparative Medicine Institute, College of Veterinary Medicine, North Carolina State University, Raleigh, NC 27606, USA
| |
Collapse
|
4
|
Barratclough A, Ferguson SH, Lydersen C, Thomas PO, Kovacs KM. A Review of Circumpolar Arctic Marine Mammal Health-A Call to Action in a Time of Rapid Environmental Change. Pathogens 2023; 12:937. [PMID: 37513784 PMCID: PMC10385039 DOI: 10.3390/pathogens12070937] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Revised: 06/16/2023] [Accepted: 07/12/2023] [Indexed: 07/30/2023] Open
Abstract
The impacts of climate change on the health of marine mammals are increasingly being recognised. Given the rapid rate of environmental change in the Arctic, the potential ramifications on the health of marine mammals in this region are a particular concern. There are eleven endemic Arctic marine mammal species (AMMs) comprising three cetaceans, seven pinnipeds, and the polar bear (Ursus maritimus). All of these species are dependent on sea ice for survival, particularly those requiring ice for breeding. As air and water temperatures increase, additional species previously non-resident in Arctic waters are extending their ranges northward, leading to greater species overlaps and a concomitant increased risk of disease transmission. In this study, we review the literature documenting disease presence in Arctic marine mammals to understand the current causes of morbidity and mortality in these species and forecast future disease issues. Our review highlights potential pathogen occurrence in a changing Arctic environment, discussing surveillance methods for 35 specific pathogens, identifying risk factors associated with these diseases, as well as making recommendations for future monitoring for emerging pathogens. Several of the pathogens discussed have the potential to cause unusual mortality events in AMMs. Brucella, morbillivirus, influenza A virus, and Toxoplasma gondii are all of concern, particularly with the relative naivety of the immune systems of endemic Arctic species. There is a clear need for increased surveillance to understand baseline disease levels and address the gravity of the predicted impacts of climate change on marine mammal species.
Collapse
Affiliation(s)
- Ashley Barratclough
- National Marine Mammal Foundation, 2240 Shelter Island Drive, San Diego, CA 92106, USA
| | - Steven H. Ferguson
- Arctic Aquatic Research Division, Fisheries and Oceans Canada, Winnipeg, MB R3T 2N6, Canada;
| | - Christian Lydersen
- Norwegian Polar Institute, Fram Centre, 9296 Tromsø, Norway; (C.L.); (K.M.K.)
| | - Peter O. Thomas
- Marine Mammal Commission, 4340 East-West Highway, Room 700, Bethesda, MD 20814, USA;
| | - Kit M. Kovacs
- Norwegian Polar Institute, Fram Centre, 9296 Tromsø, Norway; (C.L.); (K.M.K.)
| |
Collapse
|
5
|
Lindsay SA, Fulham M, Caraguel CGB, Gray R. Mitigating disease risk in an endangered pinniped: early hookworm elimination optimizes the growth and health of Australian sea lion pups. Front Vet Sci 2023; 10:1161185. [PMID: 37180065 PMCID: PMC10168540 DOI: 10.3389/fvets.2023.1161185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2023] [Accepted: 04/04/2023] [Indexed: 05/15/2023] Open
Abstract
The Australian sea lion (Neophoca cinerea) experiences high pup mortality of seasonally alternating severity, partly attributed to endemic hookworm (Uncinaria sanguinis) infection. To further explore health outcomes of early hookworm elimination, a treatment trial was conducted at Seal Bay Conservation Park, South Australia, over consecutive lower and higher mortality breeding seasons (2019, 19.2%; 2020-1; 28.9%). Pups (n = 322) were stratified into two age cohorts (median 14 d and 24 d recruitment ages) and randomly assigned to treated (topical ivermectin 500 μg/kg) or control (untreated) groups. A younger prepatent cohort <14 d old (median 10 d) was identified a posteriori. A seasonally independent growth benefit resulted from hookworm elimination across all age cohorts. The greatest relative improvements (bodyweight + 34.2%, standard length + 42.1%; p ≤ 0.001) occurred in the month post-treatment, in the youngest prepatent cohort. A significant benefit of lesser magnitude (bodyweight + 8.6-11.6%, standard length + 9.5-18.4%; p ≤ 0.033) persisted up to 3 months across all age cohorts - greatest in the youngest pups. Treatment resulted in immediate improvement in hematological measures of health - decreased anemia and inflammation severity (p ≤ 0.012). These results enhance our understanding of host-parasite-environment interactions within the context of hematological ontogenesis, confirm the seasonally independent benefits of hookworm disease intervention, and further inform conservation recommendations for this endangered species.
Collapse
Affiliation(s)
- Scott A. Lindsay
- Faculty of Science, Sydney School of Veterinary Science, The University of Sydney, Camperdown, NSW, Australia
- Faculty of Science, School of Animal and Veterinary Sciences, The University of Adelaide, Roseworthy, SA, Australia
| | - Mariel Fulham
- Faculty of Science, Sydney School of Veterinary Science, The University of Sydney, Camperdown, NSW, Australia
| | - Charles G. B. Caraguel
- Faculty of Science, School of Animal and Veterinary Sciences, The University of Adelaide, Roseworthy, SA, Australia
| | - Rachael Gray
- Faculty of Science, Sydney School of Veterinary Science, The University of Sydney, Camperdown, NSW, Australia
| |
Collapse
|