At present, no infections with the stress have been reported in human beings.
” Because this parasite can infect human beings and other animals, we want others to be knowledgeable about our findings, rapidly acknowledge cases if they encounter them, and take safety measures to prevent infection,” stated matching author Melissa Miller of the California Department of Fish and Wildlife. “We motivate others to take additional safety measures if they observe swollen systemic fat deposits in sea otters or other marine wildlife.”
A common parasite, an unusual outcome
Toxoplasma gondii is a common parasite hosted by domestic and wild felines and shed in their feces. Although healthy human beings hardly ever experience symptoms, toxoplasmosis can cause miscarriages and neurological illness.
Sea otters are specifically susceptible to Toxoplasma infection due to the fact that they live near the shoreline where they might be exposed to the parasites eggs in rainwater overflow, and they consume marine invertebrates that can concentrate the parasites.
The four sea otters described in this research study were stranded in between 2020 and 2022. All had serious swelling of their body fat– a condition called steatitis. Severe steatitis is a very uncommon finding in sea otters with toxoplasmosis.
” The appearance of this deadly type of Toxoplasma in seaside California is concerning for 2 primary reasons: First, since of possible population health impacts on a threatened species, and 2nd, since this parasite might also impact the health of other animals that are susceptible to Toxoplasma infection,” stated research study co-author Devinn Sinnott of the UC Davis School of Veterinary Medicine.
Tiny evaluation of tissues verified Toxoplasma as the cause of death for all four otters. High numbers of the parasites were observed throughout each body other than the brain, which is generally one of the significant organs impacted in sea otters with fatal toxoplasmosis.
DNA screening recognized an unusual strain of Toxoplasma called COUG in all 4 cases. This stress was first discovered in 1995 in Canadian mountain lions throughout monitoring after a close-by outbreak amongst people, but the pressure of Toxoplasma responsible for the outbreak was never ever reported. Detection of COUG in sea otters is worrying for the health and recovery of this threatened types.
” This was a complete surprise,” stated senior author Karen Shapiro of the UC Davis School of Veterinary Medicine. “The COUG genotype has never in the past been explained in sea otters, nor throughout the California seaside environment or in any other water mammal or bird.”
Sea otters under risk
All four otters were stranded during periods of high seaside rains, which implies they may have been exposed to Toxoplasma eggs by means of storm runoff. Three of the otters were stranded near each other, it is unclear whether they were all contaminated in the same area. How this unusual stress might impact humans or other animals is also unidentified.
” I have actually studied Toxoplasma infections in sea otters for 25 years, and I have never seen such extreme lesions or high parasite numbers,” Miller said. “We are reporting our initial findings to alert others about this concerning condition. Given that Toxoplasma can infect any warm-blooded animal, it could likewise possibly cause disease in animals and people that share the very same environment or food resources, including mussels, clams, oysters, and crabs that are taken in raw or undercooked.”
With increased monitoring, the COUG pressure might be identified in other animals.
” We still have much to find out,” said Sinnott. “Larger-scale studies are needed to understand the possible impact of infection by the COUG Toxoplasma stress on sea otter populations, how geographically dispersed it is, how it is being introduced into the ocean and what other animals might be affected.”
Referral: “Newly discovered, virulent Toxoplasma gondii COUG strain triggering fatal steatitis and toxoplasmosis in southern sea otters (Enhydra lutris nereis)” by Melissa Ann Miller, Cara A. Newberry, Devinn M. Sinnott, Francesca Irene Batac, Katherine Greenwald, Angelina Reed, Colleen Young, Michael D. Harris, Andrea E. Packham and Karen Shapiro, 22 March 2023, Frontiers in Marine Science.DOI: 10.3389/ fmars.2023.1116899.
The research study was moneyed by the California Sea Otter Fund, the California Department of Fish and Wildlife-Office of Spill Prevention and Response, and the Morris Animal Foundation.
Sea otters swim together in the Pacific Ocean. A lethal, freshly spotted stress of the parasite Toxoplasma gondii is threatening sea otters, and potentially other species. Credit: Laird Henkel, CDFW
A rare type of toxoplasma infection postures a risk to marine wildlife.
According to a study by the California Department of Fish and Wildlife and the University of California, Davis, 4 sea otters that washed ashore in California died from a serious and extremely unusual form of toxoplasmosis. The disease was brought on by the microscopic parasite Toxoplasma gondii. Researchers are alerting that this unusual pressure, which has actually not been formerly reported in marine animals, could present a health risk to other marine wildlife and humans.
The initial findings, published in the journal Frontiers in Marine Science, note that toxoplasmosis is an extensive event in sea otters and can be lethal. This unusual strain of the illness appears to be especially virulent and capable of quickly triggering the death of healthy adult sea otters.
The unusual stress of Toxoplasma hasnt been detected on the California coast before so is likely to be a recent arrival. Researchers are worried that if it infects the environment and the marine food cycle, it could posture a public health risk.
A fatal, newly discovered pressure of the parasite Toxoplasma gondii is threatening sea otters, and potentially other species. According to a study by the California Department of Fish and Wildlife and the University of California, Davis, 4 sea otters that washed ashore in California passed away from a highly unusual and severe type of toxoplasmosis. The four sea otters described in this study were stranded between 2020 and 2022. Extreme steatitis is an extremely uncommon finding in sea otters with toxoplasmosis.
Detection of COUG in sea otters is worrying for the health and recovery of this threatened species.