Transcript Talk #6
Human Pathogens and the Canada Goose Tyler Baratko Bio 548 Protozoans • • • • Eukaryotes Heterotrophic Motile Unicellular Group Phylum Name Flagellates Mastigophora Ciliates Ciliophora Sporozoans Sporozoa Rhizopods Sarcodina Cryptosporidium Taxonomy Phylum: Apicomplexa Class: Conoidasida Subclass: Coccidiasina Order: Eucoccidiorida Suborder: Eimeriorin Family: Cryptosporidiidae Genus: Cryptosporidium *The Different Species are of particular interest Cryptosporidium parvum • Zoonotic, or animal adapted • Majority of human disease • Infects both ruminants (cattle, sheep, goats, deer) and humans • human-to-human and zoonotic transmission pathways Cryptosporidium hominis • Previously known as C. parvum – Recent genetic discoveries have revealed small differences in the genome • Infects mostly humans • Transmitted from human to humans – Zoonotic pathways have not been observed Cryptosporidiosis • Symptoms – Diarrhea – Abdominal pain – Nausea – Fever – Fatigue • Can be life-threatening in immunocompromised A few more facts….. • 1976 was the first reported case of Cryptosporidiosis • 1993-the largest outbreak of waterborne illness in US history. – Milwaukee, WI – 400,000 infected Facts cont’d • Prevalence – 90% of sewage samples – 75% of river waters – 28% of drinking water • Resistance – Small size (4-6μm) evade sand filters – Disinfectants Giardia Taxonomy Phylum: Sarcomastigophora Subphylum: Mastigophora Class: Zoomastigophora Order: Diplomonadida Family: Hexamitidae Genus: Giardia Giardia lamblia (G. duodenalis, G. intestinalis) • Most Common in children • Cyst contaminated water • Zoonotic with deer, rodents, household pets, or cattle being carriers Giardiasis • Symptoms – Diarrhea – Cramps – Anorexia – Can be chronic Facts • Larger than Cryptosporidium @ 7-10 by 8-12 μm • Disinfectants still useless • Sand-filtering usually removes them Canada Goose and Protozoans… Where’s the Connection? Research • Strong correlation – B. Canadensis and Cryptosporidium • Documented Carriers A bit more research… • Relatively knew – Only handful of studies • Contradictory information • Controversial • Still many unanswered questions Let me pose a couple (think know and answer later) Why are oocysts dormant in the goose GI tract and not ours? Is it really a serious problem, and if so, should the Canada Goose be held responsible? Studies • Fecal droppings of migratory Canada geese, were collected from nine sites near the Chesapeake Bay • Were examined for the presence of Cryptosporidium parvum and Giardia • C. parvum found at 7 of the 9 sites • Giardia found at all 9 • Remember…these two are both thought to be zoonotic (disease that can be transmitted from animals to humans) • The pathogenesis of the oocysts were tested in mice – Each inoculated with approximately 9.0 × 104 oocysts – Intestines revealed developmental stages of C.Parvum This appears to be a problem! Many are jumping to conclusions! For example… • A study was conducted by the following: – Monmouth County Health Department – Monmouth University – Johns Hopkins School of Hygiene & Public Health • Blame the C. Goose for many health problems Their numbers 1999: 10,000 geese x 1.5 lbs./day x 365 days/yr. = 2,737.5 Tons manure • In N.J., the C. Goose population doubles every 7 years. Keeping this in mind, they estimated that this year, the numbers will look like this: 20,000 geese x 1.5 lbs./day x 365 days/yr. = 5,475 Tons manure •If the C. Goose is the main culprit for spreading the pathogens (as Monmouth County assumes), than something must be done to prevent widespread infection. A golf example… Their Solutions Giardiasis Prevention • Wash hands with soap and water after using the toilet and before handling food • Boil your drinking water for 1 minute • Avoid areas that are heavily contaminated with goose feces • Wash hands and feet after being in an area that is contaminated . • Take care not to track contamination into your home. • Do not swim in a pool that is frequented by waterfowl. Pool chlorination does not kill the giardia cysts. Cryptosporidiosis - Prevention • Wash hands with soap and water after using the toilet and before handling food • Boil drinking water for 1 minute • Avoid areas that are heavily contaminated with goose feces • Be careful not to track contamination into your home • Do not swim in a pool that is frequented by waterfowl • Stay away from domestic and farm animalsespecially young animals with diarrhea Does the Canada Goose REALLY deserve most of the blame? Prevalence of Pathogenic Genotypes • 13 sites in Ohio and Illinois • Analysis of fecal droppings (209 specimens) for Crypt. Genotypes – Crypt. Goose Type 1 and Type 2 – Crypt. Duck – Crypt. Hominis and Parvum(zoonotic types) • PCR to analyze SSU rRNA gene for bp differences. The results… • • • • • 49 of 209 positive Crypt. Goose Type 1 in 36 Crypt. Goose Type 2 in 9 Crypt. Duck Type found for the first time! Crypt. Hominis and Crypt. Parvum were found a combined 5 times. That’s only about 10%! The implications • The majority of the genotypes found are not zoonotic. – Goose genotypes are probably actually parasitic to the Geese, but the pathogencity is not known • This study shows the Canada goose as merely an accidental carrier of the infectious types. Conclusion • • • • Very new stuff Still being studied Many other variables Canada Goose DO contribute – Extent is still uncertain Questions revisited Why are oocysts dormant in the goose GI tract and not ours? Is it really a serious problem, and if so, should the Canada Goose be held responsible?