Download Post-weaning Multisystemic Wasting Syndrome (PMWS)

Post-weaning Multisystemic
Wasting Syndrome (PMWS)
What is PMWS?
PMWS is a clinical syndrome of pigs that was
first described in Canada in 1996 and has
since been reported throughout the United
States, Europe and Asia. It is a disease of
young pigs aged 6-12 weeks. Although its
exact cause is uncertain infection with
porcine circovirus type 2 (PCV2) is necessary,
usually in association with ill-defined immune
stressors such as those caused by various viral
infections. PCV2 is endemic in New Zealand pig herds in both the North and South Islands.
Does PMWS pose any human health or
food safety risk?
There is no human heath risk or food safety
issue associated with PMWS.
How does PMWS affect pigs?
Clinical signs may vary but generally include:
loss of appetite and rapid weight loss;
breathing difficulties;
jaundice causing a yellow pallor to the
skin;
diarrhoea;
enlarged lymph nodes below and behind
the lower jaw and in the groin.
Affected weaners do not respond to veterinary
treatment. Temporary improvements may result
from changes to diet, housing and other farm
management measures. There is no vaccine.
How many pigs will be affected?
On farms with PMWS about 10-30 percent of
weaner pigs are usually affected, but there
have been reports of up to 60 percent being
affected. About 80 percent of affected pigs
die.
farm must have had no contact with pigs or
their housing for 24 hours before they
enter a pig farm.
Cleaning and Disinfection – All vehicles
that have entered, or come within
10 metres of a piggery in the past must be
washed before entering another pig farm.
All equipment that has been on a piggery in
the past must be washed and disinfected
before it is taken onto another pig farm.
Persons must shower 24 hours before
entering a pig farm and clothing and
footwear must be clean. Footwear that has
entered another piggery in the past must
be soaked in a licensed disinfectant for
five minutes.
Other Animals – Contact between pigs and
other animals should be prevented where
possible. All farmers should maintain a
thorough rodent reduction programme.
Other Pigs – When purchasing new stock,
producers should discuss biosecurity issues
with their veterinarian. In all instances, it is
recommended that pigs are obtained from
the minimum number of sources.
It is unclear what causes PMWS but it is closely
associated with PCV2 and may be triggered by
stresses on the immune system caused by other
viruses or environmental stresses.
No stand down period or cleaning and disinfection
is required where contact was with pigs or their
environment on the same farm. Individual farmers
may choose to consider herds on separate
properties as being part of the same farm e.g.
where the breeding and growing herd are on
different sites.
What can you do to guard your herd
against this disease?
In any event, watch your herd carefully and if you
and your veterinarian suspect the disease report
the matter at once by phoning:
What is the cause of PMWS?
Standard on-farm biosecurity measures that
protect against the introduction of infectious
diseases should be effective against PMWS,
these include:
Stand Down Period – All persons,
vehicles and equipment that enter a pig
MAF Exotic Disease
and Pest Hotline
0800 809 966
For more information on PMWS go to:
www.maf.govt.nz/biosecurity/pests-diseases/animals/pmws/index.htm
For a copy of the booklet Control of PMWS and PDNS go to:
www.pork.co.nz/pmws/default.asp