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: EimeriorinFamily: 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

http://www.dpd.cdc.gov/dpdx/HTML/Frames/A-F/Cryptosporidiosis/body_Cryptosporidiosis_life_cycle_lrg.htm

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

TaxonomyPhylum: 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 animals-

especially 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?