LECTURE 22- One world, One Health

what is one health

an integrated, unifying approach to sustainably balance and optimize the health of people, animals and ecosystems

• building capability to detect and respond to emerging epidemic and pandemic disease threats

what is the focus for one health

diseases that are capable of infecting multiple host species between multiple populations (zoonotic diseases)

what do you do if you have a notifiable disease

if you or a pet have a disease on the list, must be notified by local authorities and government

how many human diseases are zoonotic in origin

75%

how many zoonotic diseases represent a threat to animals

over 200

Plague (Yersinia Pestis)

• fatal and easy transmition (~600 infection/year)

• treatable with antibiotics

• managing rodents can reduce spread

how many cases of plague (Yersinia Pestis) were in NZ

21 cases between 1900 and 1911

what’s the most notified disease in NZ

Campylobacteriosis

Campylobacteriosis

• gastro-type disease

• peaks in summer and spring

• Symptoms: abdominal pain, fever, watery diarrhoea, sometimes bloody stools

• Young children and older population are more susceptible

what campylobacter infection are there

→ C. jejuni: (poultry, cattle and domestic pets)

→ C. coli: (pigs and poultry)

→ C. fetus: (abortions in cattle and sheep)

how does Campylobacteriosis spread

• through humans eating contaminated meat (undercooked chicken) or unpasteurized milk- most common

• drinking water contaminated with fecal water

• direct contact with animals

what is the second most common bacterial illness in NZ

Salmonella (Salmonellosis)

where does salmonella live

in the gust of domestic and wild animals  (birds, poultry), fish, reptiles, amphibians, insects, pigs, cattle, rodents, pets and humans

what are common routes of infection for salmonella

food, water, animals contact and exposure to farm environment

how does salmonellosis spread on farms

• tissue from aborting ewes

• sheep shedding bacteria in faeces when stressed

• contaminated water sources and yard dust

• work-related exposure to organisms (e.g farm workers)

what is one of the most common parasites globally

Toxoplasmosis (toxoplasma gondii)

how is Toxoplasmosis commonly spread

 through eating infected meat and oocysts in faeces of infected cats

Toxoplasmosis

→ usually harmless (certain populations are more vulnerable)

→ can cause serious problems if pregnant or have weak immune system

→ second most common cause of abortion in sheep

Leptospirosis

• commonly acquired by people working in the dairy industry (milking or handling cows)

• 5 variants in NZ

what animals are reservoir hosts for leptospirosis

feral animals, rats, mouse, possum, hedgehog, rabbit, deer, dog, goat, pig

Bovine tuberculosis

• existed in NZ for a long time

• possums are a reservoir species

• transmitted from animals (mostly cattle) to humans

what year was the national strategy for Bovine tuberculosis introduces

1998

Influenza

• viral infection

• constantly mutating and creatin new strains

• started from spanish flu pandemic in 1918

how is influenza managed

• annual WHO consultations for flu vaccines

• 2019: global influenza strategry launched (2019-2030)

how is Coronavirus (CoV) transmitted

transmitted from bats, to (potentially snakes), then to humans

Legionnaires Disease

• largest rates of legionnaires is in NZ

• not zoonotic or contagious

• lives in the environment (soil, water systems, compost, etc.)

how is Legionnaires Disease transmitted

• breathing airborne particles (from water sources, or dust)

• Most common infection is from exposure to potting mix or compost

what’s involved in pasture management to prevent zoonotic diseases

• pasture quality

• controlling animal disease/reproduction/parasite infection

• be mindful of diseases that can live in silage, multi-species grazing, or rotation lengths

why does NZ have a reputation as a producer of safe food

• biosecurity gives NZ a disease-free status

• traceability of foodborne illnesses ensures food safety

• animal welfare and human health are priorities