Emerging viruses in Companion Animals. Pesavento - Viral Emergence.pdf · Patricia A. Pesavento [email protected] Emerging viruses in Companion Animals Consider diagnostics,

Patricia A. Pesavento [email protected]

Emerging viruses in Companion Animals Consider diagnostics, pathogens, and pathogenesis

Outline of conversation1.!Emergence!pathways!

! Viral!evolution:!Parvovirus!! Ecosystem!impact!

2.!Canine!in9luenza!

3.!Diarrhea,!polymicrobial!disease,!and!!!!diagnostic!dilemmas!(Circo,!Boca,!Astro,!Corona,!Giardia,!Campy!etc)

Viral evolution will happen. You are the most likely person to discover changes.

Our!pets!are!a!relatively!unguarded!interface!15!million!dogs/cats!vs.!9!million!cows,!280!vs.!3000!veterinarians

Polymicrobial!infections

Stress

Impact!of!medical!intervention

Mechanisms of Emergence

! Virus ! changes in virulence, episodic

epidemics, species-jumping ! Host

! Breeds, medicine, and contact ! Environment

! Anthropogenic

! Viral Discovery

Help the individual animal, help the herd, identify emergence, identify zoonoses

Why do diagnostics?

Having a diagnosis will result in a better prognosis.

REGARDLESS OF WHETHER OR NOT THERE IS A CURE

• pain&• duration&of&disease&• time&to&death&

Viral&Discovery&

Method Detection Limitation

PCR specific, sensitive, standard

Requires knowledge of target pathogen

Microarray broad range of pathogens (family)

not broadly available, cost

Metagenomics (massive sequencing) almost unbiased depends on informatics,

costly, slow

EM unbiased not broadly available, not always specific

Culture bacteria biased

Serology broad range of systemic pathogens exposure only

Anthony S J et al. mBio 2013

Viral!discovery!curve

Estimate!that!mammals!alone!harbor!at!least!320,000!viruses!waiting!to!be!discovered

Interpretation of results

quantitative PCR Based on the intact presence of genetic material Highly sensitive Highly specific Fast turn-around time for results Many different types of biologic samples can be interrogated

Organism Salmonella Giardia Canine coronavirus

Canine parvovirus 2

Canine distempervirus Campylobacter

Clinical signs Fever, sepsis,

anorexia, may or may

not be hemorrhagic

Acute/chronic/ intermitt

ent

Acute diarrhea, with vomiting can have fever

Acute, hemorrhagic

Vomiting, diarrhea

Prevalence

Found at LOW rates in

both non-diarrhetic

and diarrhetic animals (<2%)

Overall 8%

50% in puppies

up to 100% in shelters

15-26% healthy 60% in non-diarrhea in a

shelter 73% in diarrhea

in a shelter

High in identified

cases (young, hemorrhagic

diarrhea)

Not done. GI can be presenting sign

Clinical significance significant,

zoonotic potential

can treat, but don’t re-

test

NOT significant usually, but can

besignificant significant

also….Campylobacter coli, C.p A gene, C. p E gene, Cryptosporidium

*

Diagnostics of microbes: Microbiology in the post-genomics era

Campylobacter!spp!were!isolated!from!5%!dogs!with!diarrhea!and!28%!control!dogs...

No!signi9icant!difference!(%!dogs)!Campylobacter!isolated!from!young!dogs!with!and!without!diarrhea.!

58%!of!healthy!dogs!and!97%!of!diarrheic!dogs!shed!detectable!levels!of!Campylobacter!spp.

Some spp. of Campylobacter are significantly associated with diarrhea, and polymicrobial infections can be important

50 % mortality severe disease

increased shedding

EPEC

= inapparent-mild disease

1010 cfu

Pakpinyo et al, Avian Dis, 2003

tcv

7 days EPEC

104 cfu

=

Polymicrobial infections

Host susceptibilityEnvironmental interaction is unique for every animal Anthropogenic challenges Movement (animals=mismatch.. and pathogens) Bottlenecks

eg a simultaneous outbreak of MDR Salmonella Schwartzengrund in US, Denmark, Thailand

Animal-Human Interface

16

KF Hurley

•  Emergence of Virus Escape Mutants after Immunization with Epitope Vaccine G. Weidt, et al J Virol. (1995 )November; 69(11): 7147–7151!

•  Influenza Type A Virus Escape Mutants Emerge In Vivo in the Presence of Antibodies to the Ectodomain of Matrix Protein 2

Darya Zharikova et al J Virol, June (2005), p. 6644-6654, Vol. 79, No. 11!

• Genogrouping of Vaccine Breakdown Strains of Feline Calicivirus in Japan Ohe et al Vet Res Comm, 31 (2007) 479-507!

Is Vaccination Driving Emergence?

Case: 1 year old Beagle-cross

1012 C. S. Potten and M. Loeffler

Mouse 2x1O8 cells shed/small intestine/dayMan «1011 cells shed/small intestine/day

1400cells/villus/day

300 cells/crypt/day/JM/J

VILLUS3500 cells 0

Tc»24h

(P) Paneth cells

C.S. Potten, 1998

1012 C. S. Potten and M. Loeffler

Mouse 2x1O8 cells shed/small intestine/dayMan «1011 cells shed/small intestine/day

1400cells/villus/day

300 cells/crypt/day/JM/J

VILLUS3500 cells 0

Tc»24h

(P) Paneth cells

2 x 108 cells shed per small intestine/day

1400 cells/villus per day

Calicivirus, Coronavirus, Astrovirus, enteroviruses, E. coli, Cryptosporidium, Rotavirus…polymicrobial problems

Parvovirus detection test?

Ag detection (fecal ELISA, aka SNAP)

Diarrhea panel (real time quantitative PCR)

CBC, Chemistry

Antimicrobials

Other supportive information

Spike gene mutations & host range

• FPV has not undergone significant changes in antigenic and biological properties since 1920

• CPV has undergone significant changes (1978): CPV-2a, CPV-2b, CPV-2c

• Host range determinant: spike gene (VP2)

• 6 AA changes differentiate FPV from CPV (80, 93, 103, 323, 564, and 568)

• 5 AA changes differentiate 2a, b and c from CPV-2 (87, 300, 305, 426, and 555)

• Host range determinants: AA 93, 375, and 426

1.Do newly recognized parvovirus strains have differences in virulence?

• Glu-426 mutation (VP2) = 2c Parvovirus

• Widespread in Europe (2000) and US

• Vaccine susceptible

• Ag test valid

CPV 2C

Reconsidering dogma: What is virulence?

Decaro N, Desario C, Addie DD, Martella V, Vieira MJ, Elia G, et al.Molecular epidemiology of canine parvovirus, Europe. Emerg Infect Dis 2007 Aug.

Case Breed Age Type

1 Min pin 2c

2 pit 6 mo CPV310

3 chihuahua 3 mo 2c

4 pit 2 mo 2c

5 chihuahua 6 mo

6 mix 8mo CPV310

7 shepherd <2 mo 2c

8 maltese 6 mo

9 pit 6 mo 2c

10 pit 4 mo 2c

11 pit X 6 mo 2c

12 X 6 mo 2c

13 X 3 mo 2c

14 pitpit 4 mo 2c

15 adult 2c

16 2c

17 2a

Dr. Jyothi Robertson, Koret Shelter Medicine Service

CPV$2c$in$California:

Mechanisms for rapid occupation by 2c Parvovirus

•higher virulence

more severe? susceptibility in adults? vaccine resistance?

• lower virulence?

shedding can be 1010-1012 per gram feces In a day 2 x 1019 single dose is 105 viruses

Endemic(pathogens(of(higher(or#lower#virulence(might(be(successful.

The cat-dog shuffle

Cross-Species Transmission of Canine Parvovirus 2 to

Healthy Shelter Kittens and Cats with Feline

Panleukopenia Syndrome

Christian Leutenegger, DrMedVet, PhD, IDEXX Laboratories, Inc., Sacramento, CA Hongwei Liu, MS, Niels C. Pedersen, DVM, PhD Center for Companion Animal Health, University of California, Davis, CA;

2. Do CPV strains cause disease in privately owned US cats?

3. Can we identify CPV strains in asymptomatic US shelter cats?

4. Does FPV expand its host range and infect US dogs?

FPV vs CPV Assay in Infected Cats

Cats can be infected with CPV (2b, 2c) or FPV (CPV-like mutation) Cases: sick cats with clinical diarrhea

#Cust

CountryShelter

FlagPanel Material Num Desc

Universal Parvo PCR Result*

FPV CPV Call

1 JP N FELINE DIARRHEA PANEL COMP 8.59 3.402 3.248 FPV / CPV

2 US N FELINE DIARRHEA PANEL COMP 22.92 2.746 8.631 CPV

3 US N FELINE DIARRHEA PANEL COMP 7.18 9.826 1.361 FPV

4 JP N FELINE DIARRHEA PANEL COMP 27.19 7.59 1.06 FPV


6 MX N FELINE DIARRHEA PANEL COMP 6.85 10.292 1.321 FPV



9 KR N FELINE DIARRHEA PANEL COMP 7.4 9.364 1.015 FPV


11 US Y FELINE DIARRHEA PANEL COMP 26.21 8.277 1.044 FPV

12 US N DIARRHEA PCR COMP PLUS FE 27.84 2.323 2.084 FPV


14 US N FELINE DIARRHEA PANEL COMP 25.05 2.587 7.72 CPV

15 JP N FELINE DIARRHEA PANEL COMP 5 10.229 1.422 FPV

16 KR N FELINE DIARRHEA PANEL COMP 20.22 2.578 2.446 FPV / CPV


18 US N FELINE DIARRHEA PANEL COMP 9.13 3.785 3.443 FPV / CPV


20 JP N FELINE DIARRHEA PANEL COMP 15.42 9.388 0.959 FPV* CP Value (Cycle point)

FPV vs CPV

Privately owned cats, sick Clear identification of canine parvovirus infections!

Shelter kittens Clear identification of canine parvovirus 2a, b, and c CPV-2c cannot be explained by vaccine High Parvovirus load in sick and healthy kittens!

Privately owned dogs, sick No dog has been identified with FPV infection

Parvovirus Types in Shelter Kittens

367 fecal samples for Parvovirus typing (July ‘10, July ‘11, January ‘12)

• June 2010: 47 • June 2011: 217 • Janu 2012: 103

Two categories of parvovirus load Low viral load <1.2 million viral equivalents per gram of stool • Environmental contamination • Vaccine interference (MLV) • Carrier with no clinical manifestations High viral load >1.2 million viral equivalents per gram of stool • Normally associated with (some sort of) clinical signs • Highest viral load detected: 2.38 x 1012 (2.38 Trillion)

34

Dora the Labrador

A"watermold"story......

35

A"watermold"story......

help the individual animal

help the herd

identify emergence

identify zoonoses36

37

Rice, Golf, and Lawncare?

Canine Influenza• Two distinct strains of IAV have emerged in domestic

dogs, with each circulating widely for several years. • Clinical presentation in dogs

herd individual

• Diagnostics • Exposure (serology) and viremia (shedding and

circulation) • Natural history of influenza, myths and predictability

Streptococcus, isolation in normal dogs

conjunctiva

oropharynx

skin

genital

urinary

gastrointestinal

When is isolation significant?

*From where is the isolate?

Co-pathogens?

Herd Health (Shelter perspective)

References: Chalker et al, 2003Kim et al, 2007Pesavento et al, 2008Byun et al 2009Britton et al, 2010

Canine Influenza Virus H3N8! Data range 2007 – April 2015

! CRD panel includes 11 infectious agents & 7 quality controls

! Frequency has declined over the past 4 years

! Chicago CIV H3N8 cluster detected in 2008, single positives in the past 6 years

! Other active clusters in Southern California, Texas and New York

45

Establishment"of"influenza"in"new"hosts

Parrish"et"al,"2015

H3N2 Influenza Virus

• Submissions across the US from March to May 2015 were re-tested with H3N2 real-time PCR in a retrospective study

• March: 949 swabs were tested of which 89 or 9.5% tested positive • April: 871 swabs were tested of which 173 or 19.9% were positive.

• Positive cases: (March 1st – May 5th):Alabama, n=2

California, n=1 Illinois, n=222 Indiana, n=2 Michigan, n=3 Minnesota, n=6 New Jersey, n=1 Texas, n=1 Virginia, n=1 Wisconsin, n=3

Data source: unpublished data, IDEXX Laboratories, Inc. Version 05 14 2015

Canine&Circo*,&Boca*,&and&Kobuviruses

Virus&:&Host&Interaction Pathogen&discovery

Kobuvirus Sapovirus Circovirus Bocavirus Amdovirus

Discovery*vs.*research*that*determines*causality*and*pathogenesis

Vasculitis?

Diarrhea

Normal"artery Case"1:arteriAs

Vasculitis,&histiocytic&disease

virus

DogCV2063 bp

RepCap

ORF3

PCV21768 bp

Rep

Cap

ORF3

FiCV StCV

RaCV CaCV CoCV

GuCV BFDV

SwCV GoCV

DuCV PCV1

PCV2 DogCV-UCD3 Blood

Canine CV isolate 214 DogCV-UCD2 Feces DogCV-UCD1 Tissue

Barbel CV CyCV NG13

Catfish CV CyCV TN25 CyCV PK5034 CyCV PK5006

CyCV NG chicken 8 CAV

100

6499

100

92100

99100

8970

8797

99

81

99

95

68

52

0.1

In*feces:

healthy&dogs:&&& & & & & & 14/204&& & & 6.9&% diarrheic&dogs&& & & & & & 19/168& & & 11.3&%&

& Thirteen&of&19&positives&dogs&(68%)&were&co*infected&with&one&or&multiple&& other&pathogens,&including&Canine&Enteric&Coronavirus,&Cryptosporidium& & spp.&,&C.&perfringens&alpha&toxin,&Giardia&spp.,&Salmonella&spp.,&Campylobacter&& jejuni,&and&Campylobacter&coli

In*blood:

Dogs&with&thrombocytopenia& & 16/480&& & & 3.3% or&neutropenia& (similar&to&that&reported&previously&in&canine&serum&samples&(2.9%,&6/205)

One*amplicon*from*blood*samples*had*>10%*nucleotide*distance*to*DogCVAUCD1&2.&

Frequency&of&dogCV&detected&by&real&time&PCR

Frequency&of&dogCV&detected&by&real&time&PCR

Frequency&of&dogCV&detected&by&serology?

B e r n i c e B a r b o u r F o u n d a t i o n

Documents

Emerging viruses in Companion Animals. Pesavento - Viral Emergence.pdf · Patricia A. Pesavento [email protected] Emerging viruses in Companion Animals Consider diagnostics,