Menangle

Center for Food Security and Public Health Iowa State University - 2004

OverviewOverview

• Organism• Economic Impact• Epidemiology• Transmission• Clinical Signs• Diagnosis and Treatment• Prevention and Control • Actions to take

The Organism

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The OrganismThe Organism

• Paramyxoviridae−Rubulavirus

• Syncytia and vacuolation• Not highly contagious

−Spreads slowly throughout the herd• Does not survive in environment for

very long

Importance

Center for Food Security and Public Health Iowa State University - 2004

History andEconomic Impact

History andEconomic Impact

• Newly isolated in 1997−New South Wales, Australia −Loss of fetuses and piglets−Reduced size and number of litters−Pseudopregnancy in sows −All postnatal pigs seroconvert

• Decreased number of animal will be economically damaging

Epidemiology

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HistoryHistory

• 1997: New South Wales, Australia−2,600 sow intensive piggery−4 breeding units−21 week period−Mummified fetuses and stillborn piglets−Reduced farrowing rates−Reduced number and size of litters

Transmission

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TransmissionTransmission

• Animal−Exact mechanism unknown

Fecal-oral or urinary-oral suspected

−Reservoir Fruit bats (flying foxes) Roost near piggery

• Human−Exact mechanism unknown−Very close contact with infected pig

required

Center for Food Security and Public Health Iowa State University - 2004

Pteropus speciesPteropus species

• Fruit bats, flying foxes−Pteropus poliocephalus

• Native to Australia• Found seropositive for

Menangle before and during 1997 outbreak

The grey-headed flying fox (Pteropus poliocephalus)

Animals and Menangle

Center for Food Security and Public Health Iowa State University - 2004

Clinical SignsClinical Signs

• Seroconvert in 10-14 days• Reproductive disease

−Fetal mummification and stillbirths−Reduced farrowing rate−Reduced number and size of litters−Abortions

• No clinical signs in postnatal pigs• Other animal species seronegative

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Post Mortem LesionsPost Mortem Lesions

• Mummification• Stillborns• Severe degeneration of

brain and spinal cord• Domed cranium• Histopathology

− Degeneration, necrosis of nervous tissue− Inclusion bodies− Nonsuppurative myocarditis

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Morbidity/ MortalityMorbidity/ Mortality

• Farrowing percentage down to 38%• Number of live piglets per litter

declined • Mummified fetuses, stillborn piglets

−Arthrogryposis, skeletal deformities−Degeneration of brain and spinal cord

• Occasional abortions

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Differential DiagnosisDifferential Diagnosis

• Classical swine fever• Porcine reproductive and respiratory

syndrome• Porcine parvovirus• Aujesky’s disease (pseudorabies)• Blue eye paramyxovirus

− (La Piedad Michoacan)

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SamplingSampling

• Before collecting or sending any samples, the proper authorities should be contacted

• Samples should only be sent under secure conditions and to authorized laboratories to prevent the spread of the disease

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DiagnosisDiagnosis

• Clinical− Increased proportion of mummified and

stillborn piglets• Laboratory Tests

−Serology - antibody (sows) Virus neutralization, ELISA

−Virus isolation (piglet) For definitive diagnosis Brain, lung, myocardial tissue

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Treatment Treatment

• No treatment• No vaccine• Once infected, no further

reproductive failures occur

Menangle in Humans

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Public Health SignificancePublic Health Significance

• Two human cases−Sudden fever, malaise, chills,

drenching sweats, headache, myalgia

−Followed by spotty, red, non-pruritic rash

−No coughing, vomiting, or diarrhea−Recovered in 10-14 days

Prevention and Control

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Recommended ActionsRecommended Actions

• Notification of Authorities−Federal:

Area Veterinarian in Charge (AVIC) www.aphis.usda.gov/vs/area_offices.htm

−State veterinarian www.aphis.usda.gov/vs/sregs/official.htm

• Quarantine

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Prevention and ControlPrevention and Control

• Avoid contact between fruit bats and swine

• Spread through population by time signs of disease are seen

• Endemic population−Remove pigs ages 10-16 weeks−Restock with unexposed pigs or pigs

known to be immune to the virus• No vaccine available

Additional Resources

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Internet ResourcesInternet Resources

• APHIS-Center for Emerging Issues− www.aphis.usda.gov/vs/ceah/cei/menangle.htm

• CSIROnline (Commonwealth Scientific & Industrial Research Organisation)− www.csiro.au/index.asp?type=faq&id=Menangle

• Communicable Diseases Network Australia− www.health.gov.au/pubhlth/cdi/pubs/pdf/

batsgen.pdf

Acknowledgments

Development of this presentation was funded by a grant from the Centers for Disease Control and Prevention to the Center for Food Security and Public Health at Iowa State University.

Author:

Co-authors:

Reviewer:

Glenda Dvorak, DVM, MS, MPH

Anna Rovid Spickler, DVM, PhDRadford Davis, DVM, MPH, DACVPM

Bindy Comito Sornsin, BA

Acknowledgments