Can Animal Sentinels Link Can Animal Sentinels Link Ecosystem and Human Ecosystem and Human

Health?Health?

Peter Rabinowitz MD MPHPeter Rabinowitz MD MPH

Yale University School of Yale University School of MedicineMedicine

Challenges in Human Challenges in Human Environmental HealthEnvironmental Health

Clinical EncountersClinical Encounters Often hard to tease our environmental factors Often hard to tease our environmental factors

from other more “medical” risk factors. from other more “medical” risk factors. Environmental Health Tracking Initiatives:Environmental Health Tracking Initiatives:

Difficulty correlating human health outcomes Difficulty correlating human health outcomes (asthma, cancer, etc.) with environmental (asthma, cancer, etc.) with environmental variablesvariables

The Problem: The Problem: Linking Environmental Health and Linking Environmental Health and

Human HealthHuman Health Mobility of Human populationsMobility of Human populations Exposures low levelExposures low level Long latency periods for some exposuresLong latency periods for some exposures

Can Animal Sentinels Be the Can Animal Sentinels Be the Missing Link?Missing Link?

Potential Advantages of Potential Advantages of Animal Sentinels Animal Sentinels

Animals may be Animals may be more susceptiblemore susceptible than than humans to particular hazardshumans to particular hazards

Animals Animals may be more exposedmay be more exposed thanthan humans to environmental hazardshumans to environmental hazards

Shorter latencyShorter latency due to short lifespan, due to short lifespan, intergenerational period to see effects of intergenerational period to see effects of chronic exposureschronic exposures

Traditional Human Health Traditional Human Health Perspective on (Non-lab) AnimalsPerspective on (Non-lab) Animals

Do animals pose direct threat to human Do animals pose direct threat to human health? health? (“Us vs. Them”)(“Us vs. Them”) Infectious agentsInfectious agents

• RabiesRabies• Plague, etc.Plague, etc.

Toxic agents (food animals)Toxic agents (food animals)• Mercury, PCBs in fish, etc.Mercury, PCBs in fish, etc.

Traditional Response: Traditional Response: “Blame the Animal”“Blame the Animal”

Avoidance Avoidance QuarantineQuarantine EducationEducation Personal protectionPersonal protection

Vector/reservoir population controlVector/reservoir population control Vaccines and drugsVaccines and drugs

Animals Sentinels and Animals Sentinels and “Shared Risk”“Shared Risk”

Is infection or toxin in Is infection or toxin in an animal a “sentinel an animal a “sentinel event” warning of a event” warning of a shared riskshared risk from from environmental environmental hazards?hazards?

A conceptual leap A conceptual leap from “Us vs. Them”from “Us vs. Them”

““Shared Risk” ModelShared Risk” Model

Communication between animal and Communication between animal and human health clinicianshuman health clinicians

Early recognition of hazardsEarly recognition of hazards Enhanced prevention and treatmentEnhanced prevention and treatment Growing body of knowledge linking animal Growing body of knowledge linking animal

and human healthand human health

““Shared Risk” Example:Shared Risk” Example: Asthma Asthma

Human prevalence increasingHuman prevalence increasing Attributed to multiple environmental factors, Attributed to multiple environmental factors,

including respiratory irritants, mold and other including respiratory irritants, mold and other allergens, inadequate , air qualityallergens, inadequate , air quality

Still difficult to correlate asthma rates with Still difficult to correlate asthma rates with particular environmental variables, indoor vs. particular environmental variables, indoor vs. outdoor exposures play a roleoutdoor exposures play a role

Could animals serve as asthma sentinels?Could animals serve as asthma sentinels?

Who Stays in the House All Day?Who Stays in the House All Day?

Case of Shared Risk Case of Shared Risk for Asthmafor Asthma

Asthma is diagnosed in catAsthma is diagnosed in cat Testing of cat reveals reactions to several Testing of cat reveals reactions to several

allergens and irritants in the environmentallergens and irritants in the environment Steps are taken to improve conditions that Steps are taken to improve conditions that

help both cat and humanshelp both cat and humans Vet and MD talkVet and MD talk Family’s physician is is able to detect early Family’s physician is is able to detect early

asthma in teenager living in houseasthma in teenager living in house

Why We Are Not There YetWhy We Are Not There Yet

We don’t know much (anything?) about:We don’t know much (anything?) about: How does cat asthma differ from human asthma?How does cat asthma differ from human asthma? Are cats more Are cats more susceptiblesusceptible than humans to particular than humans to particular

asthma triggers?asthma triggers? Do cats have higher exposures to particular Do cats have higher exposures to particular

allergens?allergens? Does asthma develop Does asthma develop soonersooner in cats than humans in cats than humans Are there cases of cat asthma providing Are there cases of cat asthma providing early warningearly warning

for humans? for humans?

Example: Avian InfluenzaExample: Avian Influenza

Shared Risk Ideal for AIShared Risk Ideal for AI

Reports of AI infection in animals leads to Reports of AI infection in animals leads to quick interventions to reduce human quick interventions to reduce human exposure riskexposure risk

We reliably track animal cases of We reliably track animal cases of emerging AIemerging AI

And we use the animal data to better And we use the animal data to better understand the environmental risk factors understand the environmental risk factors for both animal AND human infectionfor both animal AND human infection

Why We’re Not There YetWhy We’re Not There Yet

Linkage between human cases and poultry Linkage between human cases and poultry exposure poorly understood- no evidence of exposure poorly understood- no evidence of wildlife-human transmission of HP H5N1wildlife-human transmission of HP H5N1

We are still learning about environmental risk We are still learning about environmental risk factors for spread and propagationfactors for spread and propagation

We don’t know about relative exposure risks of We don’t know about relative exposure risks of animals and humans or relative susceptibilityanimals and humans or relative susceptibility

Roles of companion animals poorly understoodRoles of companion animals poorly understood So the human health implications of AI being So the human health implications of AI being

detected in an animal remains uncertaindetected in an animal remains uncertain

Animal Sentinel Evidence Linking Animal Sentinel Evidence Linking Human and Ecosystem HealthHuman and Ecosystem Health

“Us vs. Them” “SharedRisk”

Host Factors

“Medical”

Environmental Factors

“Ecology”

Human/animal Comparative Biology

“Sentinel Science”(Evidence)

*Susceptibility*Latency

*Climate

*Urbanization

*Vector ecology

*Land use

*Exposure

Epidemiology

Clinical Reports

Genomics

Disease models

Exposure Studies

The Canary Database:The Canary Database:Animals as Sentinels of Human Animals as Sentinels of Human Environmental Health HazardsEnvironmental Health Hazards

(http://canarydatabase.org)(http://canarydatabase.org) An interdisciplinary project An interdisciplinary project

funded by the National funded by the National Library of Medicine Library of Medicine

Canary DataCanary Data

Assembles studies of animals as sentinelsAssembles studies of animals as sentinels Highlights evidence providing linkages to Highlights evidence providing linkages to

human healthhuman health Data summariesData summaries Identifies evidence gapsIdentifies evidence gaps

The project is searching the scientific literature The project is searching the scientific literature for evidence that various animal species could for evidence that various animal species could fulfill any of the following “sentinel” criteria:fulfill any of the following “sentinel” criteria: Increased SusceptibilityIncreased Susceptibility Higher ExposureHigher Exposure Shorter LatencyShorter Latency Evidence of providing early warning for humansEvidence of providing early warning for humans Role of environmental factorsRole of environmental factors

Use of Canary DataUse of Canary Data

Veterinarian is seeing cat with asthmaVeterinarian is seeing cat with asthma Checks Canary database, sees that cats Checks Canary database, sees that cats

are more likely than humans to react to ---are more likely than humans to react to --- Is able to use this info to screen for Is able to use this info to screen for

reactionreaction Is able to use info to discuss with Is able to use info to discuss with

physicianphysician

Use of Canary Data (cont.)Use of Canary Data (cont.)

Public health department is seeing Public health department is seeing mortality of birdsmortality of birds

Checks Canary database for ways to link Checks Canary database for ways to link to human health- including environmental to human health- including environmental variables (and human factors) associated variables (and human factors) associated with human risk from a zoonotic outbreakwith human risk from a zoonotic outbreak

Able to prioritize and carry out Able to prioritize and carry out interventions BEFORE human casesinterventions BEFORE human cases

Thanks To: Thanks To:

USGS National Wildlife Health USGS National Wildlife Health CenterCenter

F. Joshua Dein F. Joshua Dein Yale Center for Medical Yale Center for Medical

InformaticsInformatics Prakash NakdarniPrakash Nakdarni Dan ChudnovDan Chudnov

Yale School of Public HealthYale School of Public Health Matthew WilcoxMatthew Wilcox

Yale Occupational and Yale Occupational and Environmental Medicine Environmental Medicine ProgramProgram

Lynda Odofin, Zimra Gordon, Lynda Odofin, Zimra Gordon, Ann Liu, Vivian LeeAnn Liu, Vivian Lee

National Library of Medicine National Library of Medicine