Pigs Possible Hendra Vectors, New Report Warns

HENDRA VIRUS, SWINE VECTOR POTENTIAL
************************************
A ProMED-mail post

ProMED-mail is a program of the
International Society for Infectious Diseases


Date: Tue 2 Feb 2009
Source: Horsetalk [edited]



Pigs identified as possible vector for Hendra virus
---------------------------------------------------
Pigs are susceptible to the deadly Hendra virus and could potentially
transmit it to humans, Canadian researchers have discovered.

The virus occurs only in Australia and is carried by native fruit
bats. However, horses can catch the virus, most probably from
ingesting secretions from infected bats.

There have been 7 cases where the virus has been transferred from
horses to people, 4 of which proved fatal.

The 2 most recent fatalities involved equine veterinarians.

The research in Canada has shown that pigs are susceptible to the
virus. Two Landrace pigs, commonly used in the pork industry, and 5
Gottingen minipigs were inoculated with the virus, as well as half a
dozen guinea pigs, 2 of which died.

All test animals developed fever and depression. One of the 2 Landrace
pigs developed respiratory signs after 5 days and 1 of the Gottingen
minipigs developed not only respiratory signs but also mild
neurological signs. Virus was detected in all infected pigs at 2-5 days.

Clinical signs in the 2 infected Landrace pigs were more severe
compared to those observed in minipigs, the authors said. The Landrace
pigs were very sick at 5 days, with 1 developing severe depression,
respiratory distress, and possible neurological signs, requiring
euthanasia.

"Since infected pigs may shed virus through oral, nasal, and rectal
excretions, possible transmission through close contact with these
excretions may occur," the authors said. "This new finding indicates
that pigs are susceptible to Hendra virus infections and could
potentially play a role as an intermediate host in transmission to
humans."

The authors noted that a serological survey of 100 swine herds in
Queensland had found no antibodies against Hendra virus among 500
samples. "Lack of evidence for Hendra infection in domestic swine
stresses the importance of heightened on-farm biosecurity," they said.

"However, our findings may reinforce the concern about Hendra virus
infecting feral pigs if they are forced to share the same habitat as
fruit bats. This concern is based on the fact that Australia has over
23 million feral pigs living in Queensland, New South Wales, and the
Northern Territory, according to reports by Animal Control
Technologies."

The virus was first identified in 1994 as the cause of respiratory
illnesses in 13 horses and 2 people in the Brisbane suburb of Hendra.
The 1st fatality was a horse trainer.

--
Communicated by:
ProMED-mail


[These pigs were injected with the virus, but the real question is
whether they are susceptible by inhalation or ingestion of the virus?
It is possible to transmit many diseases through direct inoculation
that may not transfer in the real world.

This novel work shows pigs are clearly susceptible, but their role in
transmission of the disease has not been proven by this work, only
theorized. If the work is repeated hopefully the diligent researchers
will take the next step and place non-infected pigs into the same
locality and see if there is natural transmission. - Mod.TG]

[The reference for the study mentioned above is
Li M, Embury-Hyatt C, Weingartl HM: Experimental inoculation study
indicates swine as a potential host for Hendra virus, Vet. Res. (2010)
41: 33; available at
. -
Sr.Tech.Ed.MJ]

[see also:
2009
----
Hendra virus, human, equine - Australia (05): (QL) 20090910.3189
Hendra virus, human, equine - Australia (04): (QL) fatal 20090903.3098
Hendra virus, human, equine - Australia (03): (QL) 20090830.3052
Hendra virus, human, equine - Australia (02): (QL) 20090826.2998
Hendra virus, human, equine - Australia: (QL) 20090821.2963
Hendra virus, equine - Australia (02): (QL), RFI 20090820.2943
Hendra virus, equine - Australia: (QL) 20090811.2862
2008
----
Hendra virus, human, equine - Australia (07): (QLD) 20080821.2606
Hendra virus, human, equine - Australia (06): (QLD) 20080820.2592
Hendra virus, human, equine - Australia (05): (QLD) 20080816.2548
Hendra virus, human, equine - Australia (04): (QLD) 20080725.2260
Hendra virus, human, equine - Australia (03): (QLD) 20080720.2201
Hendra virus, human, equine - Australia (02): (QLD, NSW) 20080717.2168
Hendra virus, human, equine - Australia: (QLD) 20080715.2146
Hendra virus, equine - Australia: (Brisbane) 20080708.2076
2007
----
Hendra virus, human, equine - Australia (QLD) (04): 2nd corr. 20070903.2903
Hendra virus, human, equine - Australia (QLD) (04): 2nd corr. 20070903.2902
Hendra virus, human, equine - Australia (QLD) (03): corr. 20070903.2897
Hendra virus, human, equine - Australia (QLD) (03): corr. 20070903.2896
Hendra virus, human, equine - Australia (QLD) (02): not 20070831.2871
Hendra virus, human, equine - Australia (QLD): RFI 20070830.2851]
........................................tg/mj/jw
*##########################################################*
************************************************************
ProMED-mail makes every effort to verify the reports that
are posted, but the accuracy and completeness of the
information, and of any statements or opinions based
thereon, are not guaranteed. The reader assumes all risks in
using information posted or archived by ProMED-mail. ISID
and its associated service providers shall not be held
responsible for errors or omissions or held liable for any
damages incurred as a result of use or reliance upon posted
or archived material.
************************************************************
Become a ProMED-mail Premium Subscriber at

************************************************************
Visit ProMED-mail's web site at .
Send all items for posting to: promed@promedmail.org
(NOT to an individual moderator). If you do not give your
full name and affiliation, it may not be posted. Send
commands to subscribe/unsubscribe, get archives, help,
etc. to: majordomo@promedmail.org. For assistance from a
human being send mail to: owner-promed@promedmail.org.
############################################################
####################################