|BIGOT-CLIVOT, AURELIE - Universite De Reims Champagne-Ardenne|
|PALOS, MELISSA - Hopital Maison Blanche|
|LEPOUTRE, ALEXANDRA - Universite De Reims Champagne-Ardenne|
|BASTEIN, FANNY - Universite De Reims Champagne-Ardenne|
|BONNARD, ISABELLE - Universite De Reims Champagne-Ardenne|
|VILLENA, ISABELLE - Hopital Maison Blanche|
|AUBERT, DOMINIQUE - Hopital Maison Blanche|
|GEFFARD, OLIVIER - Institut National De Recherche En Sciences Et Technologies Pour L'Environnement Et L'agriculture(ir|
|GEFFARD, ALAIN - Universite De Reims Champagne-Ardenne|
Submitted to: Water Research
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 7/4/2016
Publication Date: 7/22/2016
Citation: Bigot-Clivot, A., Palos, M.L., Lepoutre, A., Bastein, F., Bonnard, I., Dubey, J.P., Villena, I., Aubert, D., Geffard, O., Geffard, A. 2016. Bioaccumulation of Toxoplasma and Cryptosporidium by the crustacean Gammarus fossarum: involvement in biomonitoring survey and trophic transfer. Water Research. 133:188-194.
Interpretive Summary: Toxoplasmosis, caused by the single celled parasite, Toxoplasma gondii, continues to be a public health problem worldwide. This parasites infects all warm-blooded hosts, including humans. It causes mental retardation and loss of vision in children, and abortion in livestock. The ingestion of food and water contaminated with resistant stage of the parasite, the oocyst, is now considered a major mode of transmission of this parasite. Of all the hosts infected, only cats are known to excrete oocysts in feces. Cats can excrete millions of oocysts after eating an infected prey, such as a mouse or a bird. Oocysts can survive outdoors for months. Epidemiological studies that both fresh and marine waters can be contaminated with oocysts. Mollusks can concentrate oocysts in their body and humans and animals can then become infected if they consume raw mollusks. Bivalves have been proposed as a natural filtration alternative for the detection of oocysts in water as they can and retain parasites, bacteria, and viruses for an extended period of time. In this study, the authors examined the use of fresh water crustacean to accumulate T. gondii. The fresh water crustacean, Gammarus fossarum, were exposed to different concentrations of oocysts. DNA detection of T. gondii oocysts was carried out using TaqMan real-time PCR. After 5 days of depuration, T. gondii oocysts were still present in gammarids indicating the integrative nature of G. fossarum. These results show for the first time that a freshwater crustacean is able to bioaccumulate T. gondii oocysts suggesting that Gammarus fossarum is a potential effective bioindicator of protozoan contamination in biomonitoring studies. These results will be of interest to biologists, parasitologists, and epidemiologists.
Technical Abstract: The protozoans Toxoplasma gondii and Cryptosporidium parvum are public health priorities and their oocysts can persist in environment for long time. They are present in various watercourses as recreational, surface, drinking, river, and seawater and could interact with organisms. To evaluate the capacity of a freshwater crustacean to accumulate T. gondii and C. parvum oocysts, Gammarus fossarum were exposed to 200; 2,000 and 20,000 oocysts per gammarid and per day during 21 days followed by 5 days of depuration. DNA detection of T. gondii and C. parvum oocysts was carried out using TaqMan real-time PCR. C. parvum DNA was detected in gammarids in only one out of four pools for the higher concentration and after 14-day exposure. However, concerning T. gondii, DNA was detected after 7-days exposure with the two highest concentrations, and from 14-day exposure T. gondii DNA was highlighted in gammarids for all conditions. Between 0 and 14-day, oocyst number detected increased with the exposure time, then a saturation effect was observed between 14 and 21-day for the two highest concentrations. A significant dose-response relationship was observed and the maximum quantity of oocysts detected in gammarid tissues is obtained after exposure to 20,000 oocysts per organism and per day. Thus a mean of 3.26 (± 3), 21.71 (± 15.18) and 17.41 (± 10.89) oocysts were measured by gammarid after 7, 14 and 21 days respectively. After 5 days of depuration, T. gondii oocysts were still present in gammarids indicating the integrative nature of G. fossarum. These results show for the first time that a freshwater crustacean is able to bioaccumulate T. gondii oocysts suggesting that Gammarus fossarum is a potential effective bioindicator of protozoan contamination in biomonitoring studies. Moreover, due to their important position in freshwater food webs, G. fossarum could also play a role in the trophic tranfer of protozoa.