- Hello Jeff - The situation with the A-H1N1 pandemic human
version of Swine Flu is pointing to a really bad upcoming 2009 Fall flu
season here in the US and the entire Northern Hemisphere.
- Just when you thought the news couldn't be worse - i.e.
case of Tamiflu-resistant strain of A H1N1 - we now hear about A-H1N1 inluenza
having been found in pigs in Argentina.
- Date: Fri 26 Jun 2009 Source: DEFRA, Global Animal Health
- International Disease Monitoring. Preliminary Outbreak Assessment.Reference:
- A novel influenza A/H1N1 in pigs in Argentina
- 1. Introduction
- Argentina has reported an outbreak of influenza A/H1N1
in a commercial pig farm in the Buenos Aires region [a map is included
at the above URL]. The authorities have qualified this outbreak as "a
new emerging disease" in the report. Introduction of the infection
was attributed to human to animal transmission from workers at the farm
who showed flu signs between 7 and 9 Jun 2009. According to the report,
the farm was restocked from their own restocking system in July 2008. The
infected pigs showed clinical signs up to 24 Jun 2009 and have now recovered.
The report states that in a total population of over 5500 pigs (mixed ages)
there was 30 percent morbidity but no mortality (OIE, 2009).
- 2. Situation assessment
- This is only the 2nd time that a report to OIE qualified
findings of influenza A/H1N1 in domestic pigs as "a new emerging disease".
The 1st report related to a pig population in Canada in April 2009. Influenza
A in pigs usually has a relatively short period of incubation (most often
days, rather than weeks). Given the company restocking system and that
restocking took place in mid-2008, it would be highly unlikely that this
virus was present in this pig population before and remained undetected.
The World Health Organisation (WHO) declared recently that novel influenza
A/H1N1 has reached phase 6 of global pandemic status. To date, there have
been nearly 60 000 laboratory confirmed human cases and 263 deaths reported.
Confirmation of the virus in a relatively limited number of humans was
reported from 105 countries. A limited number of these countries have reported
deaths in humans, mainly in people with underlying health conditions (WHO,
- The World Organisation for Animal Health (OIE) maintains
that previous recommendations for OIE member countries remain valid. Namely,
to monitor animal populations for signs of clinical diseases in animals;
that pork and pork products handled hygienically are not a source of infection;
that there is no justification for any ban on pigs and pig products; culling
pigs is not recommended for animal health reasons and, if so, that any
culling should be carried out according to international animal welfare
standards (OIE, 2009a).
- An EU study group coordinated by the Veterinary Laboratories
Agency, Weybridge, UK, (VLA) has completed preliminary tests on the infection
of pigs with a human-derived strain of the new variant H1N1 influenza virus.
Briefly, naive pigs, inoculated intranasally, shed virus (orally and ocular)
for between 1 and 10 days post-infection (dpi) with a peak at 3-5 dpi.
No rectal shedding or viraemia was detected. Uninfected pigs introduced
to these infected animals also became infected after contact. All infected
pigs developed mild to moderate clinical and pathological signs only. (EU
- Accumulated evidence so far suggest that the new variant
Influenza A/H1N1 continues to be primarily a human-to-human transmissible
infection which generally causes mild disease in infected people. Experimental
data on pig infections with this strain indicate that infection is localised
to respiratory tract and that viraemia is highly unlikely to be of any
significance as one of the feature of the disease. Infection also causes
a relatively mild disease in pigs. In a separate study turkeys directly
challenged with the virus did not apparently become infected. Argentina
is not an approved country for export of pigs or pig products to the EU.
- The Pig Veterinary Society has published advice to pig
keepers on protecting their herds from the risk of introducing new variant
Influenza A/H1N1 (Pig Veterinary Society, 2009).
- 3. Conclusions
- On the basis of available information, we currently consider
that there would be a negligible risk of introducing this Influenza A/H1N1
from Argentina to the UK by the legal import of pigs or pig products because
such imports are not allowed. As this latest report may indicate, another
possible route for disease introduction into pig herds in the UK would
be people that may be infected and have direct or indirect contact with
a pig farm. Therefore, it is important to continue to monitor for, and
report and submit samples from suspected influenza signs in pigs (according
to appropriate case algorithms) to relevant authorities, and maintain appropriate
biosecurity measures at pig farms at all times. We will continue to review
- 4. Authors
- Dr Mirzet Sabirovic Dr Helen Roberts
- 5. References
- - EU Study (2009) http://ec.europa.eu/food/committees/regulatory/scfcah/
animal_health/background_doc_point1_en.pdf Accessed 26 Jun 2009.
- - OIE (2009) Immediate Notification report Reference
Accessed 26 Jun 2009.
- - OIE (2009a) Novel influenza A/H1N1 pandemic: the OIE
maintains its recommendations to animal health authorities worldwide.
- http://www.oie.int/eng/press/en_090611.htm. Accessed
26 Jun 2009
- - Pig Veterinary Society (2009) Novel Influenza A H1N1
Virus protecting pigs, protecting people. http://www.pigvetsoc.org.uk/news/index.php?id=82>.
Accessed 26 Jun 2009.
- - WHO (2009) Laboratory-confirmed cases of new influenza
A(H1N1) as officially reported to WHO by States Parties to the International
Health Regulations (2005) http://www.who.int/csr/don/2009_06_26/en/index.html.
Accessed 26 Jun 2009.
- communicated by Myrtle O'Keefe (FFG) myrtle.o'<mailto:email@example.com>firstname.lastname@example.org
- As this is the first recorded transmission of the 2009
(swine origin) A (H1N1) influenza virus from humans to pigs, these observations
need to be substantiated by a molecular comparison of viruses recovered
from the two hosts. As recorded in the ProMED-mail references listed below
the origin of the A (H1N1)virus infecting pigs in a Canadian farm is unknown.
Initially it was infered that the virus had been transmitted via a farm
worker recently returned from Mexico. Subsequently it was established that
the farm worker was not infected and the origin of the Canadian outbreak
remains unresolved. - Mod.CP
- Though the facts in the above analysis by DEFRA's GAH
experts have already been available to ProMED-mail's subscribers, it seemed
to us worthwhile posting the review as an all-round, documented update.
- Patricia A. Doyle DVM, PhD Bus Admin, Tropical Agricultural
Economics Univ of West Indies Please visit my "Emerging Diseases"
message board at: http://www.emergingdisease.org/phpbb/index.php Also my
- http://drpdoyle.tripod.com/ Zhan le Devlesa tai sastimasa
Go with God and in Good Health