Kelly Lager, DVM, PhDResearch Leader
Virus Prion Research UnitNational Animal Disease Center
USDA, Agricultural Research Service
Emerging Swine Diseases Around the Globe, Producer Impact and the need for Vaccinations
OUTLINE
• Work of Others
• Update on Senecavirus A
• Commentary
• Research Perspective
• Producer Impact
• Need for vaccines
Foreign animal disease / Transboundary disease /Emerging and Re-emerging disease
• Center for Food Security and Public Health, Iowa State University
• Institute for Infectious Animal Diseases, Texas A&M University
• Center of Excellence for Emerging and Zoonotic Animal Diseases, Kansas State University
• Swine Health and Information Center
• National Pork Board
• USDA – APHIS NVSL, VS
• USDA-ARS-PIADC, SEPRL, NADC
• Department of Homeland Security
Personal Testimony for Emerging Swine Viral Diseases in USA
• Sustained economic impact since 1989
• Porcine respiratory coronavirus late 1980s
• Porcine reproductive and respiratory syndrome virus 1991
• Porcine circovirus type 2 1996
• Influenza A H3 subtype 1998
• Influenza A H1 and H3 combos 2000 to present
• Porcine epidemic diarrhea virus 2013
• Senecavirus A 2015
So Far, Less Significant Swine Viruses In USA
• Too Many to List
• Include the world, even more to list
• Additional animal and human viruses……………….
CONSTANT CHANGE OR
“IT IS ALWAYS SOMETHING”*• Influenza A viruses
• Senecavirus A
• Porcine Epidemic Diarrhea Virus
• Japanese Encephalitis Virus Riklin et al. Nat. Commun. 7:10832 doi: 10.1038/ncomms10832 (2016).
• Zika virus - insect vector, sexual transmission, vertical transmission, horizontal transmission - close contact ?
* It’s Always Something by Gilda Radner
Montiel N, Buckley A, Guo B, Kulshreshtha V, vanGeelen A, Hoang H, Rademacher C, Yoon K, Lager K
VESICULAR DISEASE IN SWINE INFECTED WITH
SENECA VALLEY VIRUS (SENECAVIRUS A)
Senecavirus A (SVA) History• First isolated in late 1980s, but not classified.• Detected in several cases of idiopathic vesicular disease in the
US and Canada since late 1980s.• SVA was also isolated a few times from normal swine.• Family Picornaviridae
• Genus Senecavirus: Senecavirus A• Genus Apthovirus: Foot-and-mouth disease virus
• Koch’s postulates have not yet been fulfilled.
2014
• Brazil first reported cases of idiopathic vesicular disease in late 2014.
• SVA was isolated from
• Vesicular fluids from mature swine
• Lesions on feet
• Serum from neonatal pigs that had diarrhea and died soon after birth
• Many herds were affected
2015• Since July of 2015 there has been a growing number of
cases in the Mid-West of swine developing a vesicular disease that resembles foot-and-mouth disease
• SVA has been identified and isolated from lesion, vesicular fluid and serum from sows
• April 2016 - About 160 cases throughout Midwest
• Mostly sows and finishing age pigs
• Reports of neonatal mortality
Dr. K-J YoonIowa State University
Provided SVA virus that had been tested by next generation sequencing for purity
Guo, et al. Emerging Inf Dis 2016:22;1325-7.
SVA IN TISSUES
1.00E+00
1.00E+01
1.00E+02
1.00E+03
1.00E+04
1.00E+05
1.00E+06
1.00E+07
2 dpi 4 dpi 6 dpi 8 dpi 12 dpi
Pig #234 Pig #235 Pig #236 Pig #237 Pig #238
Geno
mic
copi
es/u
Lof
tiss
ue
TonsilCoronary BandHeartKidneylarge IntestLiverInguinal LNMesenteric LNLungRPLNsmall IntestSnoutSpinal CordSpleenBrainSerum
Inoculate pig - Intranasal
VesicularDisease
Market weight gilts 48 h
Pathogenesis
9-week-old pigs 96 h
6-week-old pigs * 96 h Sows * 72 h <1-week-old pigs ???
*Not all pigs in group displayed vesicular lesions.
V
V
Day 3 Post SVA inoculation: coronary band skin
V: vesicleE: Epidermis, D: Dermis
Intense staining aroundEpidermal Intercellular bridges adjacent to vesicle
E
D
QUESTIONS
• Where is the virus at 1 DPI, 28 DPI, 56 DPI?
• Why is SVA a Problem Now?
• How much more to invest in research for this virus?
Research Perspective – A Shared Story
• Response time dependent on • Clinical presentation
• Staffing
• Resources
• Paperwork
• What is already known!!!!
PEDV vs. SVA
• May 2013
• State Veterinary Diagnostic Laboratories
• USDA – NVSL
• USDA – ARS-NADC-VPRU- Me
• January
• March
• May
• 2014
• Increase in funding for PEDV studies -
• 2014• Increase in funding for PEDV studies –• Increase staffing begin PEDV studies to complement
ongoing studies by others• 2015
• PEDV studies• SVA breaking - August• Re-direct resources, staffing• September animal studies
VACCINES
• Vaccine Stockpiling
• Passive Immunity Dilemma
• Immunity Gap
• Timing
• Broad-based non-specific immunostimulation & antiviral
Concluding Comments• Emerging Swine Diseases Around the Globe
• Many potential diseases• Only a problem if make it to the US.• Probability?
• PEDV• PDCoV?• SVA Brazil / USA
• Thank Goodness for Federal and State Veterinary Diagnostic Labs• Diagnostic Fees• Research grants• Federal funds - HPAIV, SIV, PEDV