Reverse Zoonosis:Reverse Zoonosis:A new way of thinking A new way of thinking about pathogen flowabout pathogen flow

Nancy P. Lung, VMD, MSNancy P. Lung, VMD, MS

Director of Veterinary Director of Veterinary ServicesServices

Fort Worth ZooFort Worth Zoo

The Science of Zoonosis Control

One-directional thinking

Pathogen Flow is DynamicPathogen Flow is Dynamic

This dynamic flow can result in This dynamic flow can result in many fascinating situations!many fascinating situations!

Reverse Zoonosis Pass-through Zoonosis

Examples from the literature Examples from the literature and from my experienceand from my experience

Animal HospitalsAnimal Hospitals AgricultureAgriculture Risks from EcotourismRisks from Ecotourism ZoosZoos

Animal Hospital SettingAnimal Hospital SettingMRSA in HorsesMRSA in Horses

VMTHVMTH 11 Cases of post-procedure infection over 11 Cases of post-procedure infection over

a 13-month perioda 13-month period Previously undiagnosed at this hospitalPreviously undiagnosed at this hospital 3/5 people associated with equine surgery 3/5 people associated with equine surgery

and recovery were positive by nasal and recovery were positive by nasal cultureculture

Likely that colonized staff transmitted the Likely that colonized staff transmitted the bacteria to the affected horsesbacteria to the affected horses

AgricultureAgriculture

Herd of 122 dairy cattleHerd of 122 dairy cattle Long standing TB negative status in Long standing TB negative status in

herdherd 14 of 122 developed clinical M. bovis14 of 122 developed clinical M. bovis Source identified from the farmerSource identified from the farmer

Asymptomatic renal M. bovisAsymptomatic renal M. bovis Infected the cattle by urinating on the Infected the cattle by urinating on the

straw in the barnstraw in the barn Risk to the swine industry from H1N1Risk to the swine industry from H1N1

Risks from Risks from EcotourismEcotourism

Tourism is now the world’s largest Tourism is now the world’s largest industry---$476 billion!industry---$476 billion!

698 million international travelers 698 million international travelers per yearper year

Ecotravel is rising by 30% per year Ecotravel is rising by 30% per year and is growing fastest in developing and is growing fastest in developing countries.countries.

EcotourismPathogen Flow

Local People

Arthropod vectors

Domestic or Wild Animals

Traveler

Endangered primate Endangered primate populations are particularly populations are particularly

vulnerable.vulnerable.

Mountain Gorillas of the Virunga Mountains

Dian Fossey’s first field work in mid 1970’s

First tourists visited camp in 1979. First gorilla group was officially

“visited” by a handful of tourists in 1981.

10,641 tourists visited in 2005!!

Pathogen Flow in the Zoo setting

Interaction between animal care staff and the collection animals

Interaction between the public and the collection animals

20/55 infected (36%)

13 elephant keepers

5 nursery staff

1 vet 1 nutritionist

MRSA-colonized caretakerUSA 300

A fascinating pass-through, amplification situation

Elephant calf MRSA Lesions

Elephant Keeper MRSA Lesion

Reducing Pathogen Flow Between the Public and

Collection Animals

Case Examples

“Jackie” the Lowland Gorilla

10yr old female Flu-like symptoms in family

group Rapid decline in Jackie—

recumbent within 48 hrs Confirmed Parainfluenza 3 Placed on life support for 7

days Eventually made a full

recovery

“Ramses”31 yr old

gorilla Pneumococcal

pneumonia Maintained in

oxygen cage Outcome--

recovered

Influenza A Secondary

pericarditis Outcome--died

“Kate”39 yr old gorilla

Chimpanzee Group

Lincoln Park ZooMarch, 2009

7 animals in a single family group

All 7 had cold/flu-like symptoms

9 yr old male—status declined rapidly

Outcome—young male died, others recovered

Confirmed human metapneumoniavirus

Upper and lower respiratory infection

Confirmed Haemophilus influenzae

Outcome--recovered

“Basan”

4yr old orangutan

Kimberly Clarke Chimpanzee Forest

Dallas Zoo

FWZ Outdoor Chimpanzee and Bonobo

exhibit

FWZ Bonobo Exhibit

How to protect the health of animals in captive settings

Exhibit design in zoos Personnel health assessment

protocols in captive animal settings Personal protective equipment

during animal interactions Public Education

Zoonosis Control Pathogen Flow is DynamicPathogen Flow is Dynamic

Protection of People and Animals Goes Hand-in-Hand