- "I think that now we are facing a new scenario where
the chances of the influenza A(H1N1)2009 virus passing to birds is
not just a possibility but a reality."
-
- Transmission of A(H1N1)2009 virus from human to birds
-
- I am sending you a second report about genetic study
of 1st transmission of A(H1N1)2009 virus from human to birds.
-
- On 23 Aug [2009] the Institute of Public Health (Chile)
communicated to ProMED-mail the 1st isolation of an [influenza] A(H1N1)
swine virus in turkeys.
-
- The finding was done by the Chilean farming agency SAG
and the confirmation and genetic studies are being done in our Institution
(national reference laboratory).
-
- On that occasion we communicated the genetic and antigenic
characteristics of the hemmaglutinin (HA) gene of the turkey's virus
in this outbreak (the virus showed 99.5 to 98.9 per cent similarity
to the [Influenza]A/California/4/2009 reference strain and 100 per
cent similarity with the strains circulating in Chile).
-
- Now, we are reporting the neuraminidase genetic sequencing
studies. In this gene the turkey strain was shown to be 99.7 per
cent similar to the pandemic strains circulating in Chile in human
cases, and to have 99.5 per cent similarity to the reference strain
A/California/4/2009, 80.5 per cent to 86.5 per cent similarity to
avian influenza A virus strains (H1N1, H5N1, H6N1, H7N1) and 83.6
to 92 per cent similarity to swine influenza virus strains (H1N1)
isolated in different countries during years 2000 to 2009. At the
end of this week we will report the results of complete genome.
-
- Julio Garcia Moreno MD, MSc Head, Biomedical Department
Instituto de Salud FAblica de Chile jgarcia@ispch.cl>
-
-
- Date: 27 Aug 2009 From: Julio Garcia Moreno MD, MSc
-
- Transmission of A(H1N1)2009 virus from human to birds
-
- Final report about genetic study of 1st transmission
of A(H1N1)2009 virus from human to birds.
-
- On 23 Aug 2009 the Institute of Public Health (Chile)
communicated to ProMED-mail the 1st isolation of a A(H1N1) swine
virus in turkeys. The finding was done by the Chilean farming agency
SAG and the confirmation and genetic studies are being done in our
Institution (national reference laboratory). On that occasion we
communicated the genetic and antigenic characteristics of the hemagglutinin
and neuraminidase gene of the turkey's virus in this outbreak. Now,
we are reporting the total genome genetic sequencing studies (nucleotides):
-
- 1. The gene that encodes for hemagglutinin (HA) was shown
to be 99.5 per cent similar to the A/California/4/2009 reference
strain and 100 per cent similar to the strains circulating in Chile
in patients.
-
-
- 2. The gene that encodes for neuraminidase (NA) was shown
to be 99.5 per cent similar to the A/California/4/2009 reference
strain and 99.7 per cent similar to the strains circulating in Chile
in patients.
-
-
- 3. The gene that encodes for a subunit of polymerase
(PB1) was shown to be 99.8 per cent similar to the A/California/4/2009
reference strain and 99.9 per cent similar to the strains circulating
in Chile in patients.
-
-
- 4. The gene that encodes for a subunit of polymerase
(PB2) was shown to be 99.8 per cent similar to the A/California/4/2009
reference strain and 99.8 per cent similar to the strains circulating
in Chile in patients.
-
-
- 5. The gene that encodes for a subunit of polymerase
(PA) was shown to be 99.7 per cent similar to the A/California/4/2009
reference strain and 99.9 per cent similar to the strains circulating
in Chile in patients.
-
-
- 6. The gene that encodes for the nucleoprotein (NP) was
shown to be 99.5 per cent similar to the A/California/4/2009 reference
strain and 99.7 per cent similar to the strains circulating in Chile
in patients.
-
-
- 7. The gene that encodes for the non-structural proteins
((NS) was shown to be 99.8 per cent similar to the A/California/4/2009
reference strain and 99.8 per cent similar to the strains circulating
in Chile in patients.
-
-
- 8. The gene that encodes for the matrix proteins (M)
was shown to be 99.8 per cent similar to the A/California/4/2009
reference strain and 99.7 per cent similar to the strains circulating
in Chile in patients.
-
- The conclusion of the genetic sequencing studies is that
the influenza virus (H1N1) isolated from turkey corresponds to a
variant of the influenza A(H1N1)2009 virus that has been circulating
in Chilean people.
-
- I think that now we are facing a new scenario where the
chances of the influenza A(H1N1)2009 virus passing to birds is not
just a possibility but a reality.
-
- This forces us to think some new strategies in order
to diminish the risk of co-infection in birds of avian influenza
virus and A(H1N1)2009 human virus. The replication of both viruses
in the same host could mix existing genetic information (reassortment)
and produce a new virus that has most of the genes of the human virus,
but a hemagglutinin and/or neuraminidase from an avian influenza
A virus (drift). This new virus might be able to infect humans and
spread from person to person and his surface proteins never been
in contact with human immunology system.
-
- Some strategies to evaluate are:
-
- 1. Review the established priorities for use the new
A(H1N1)2009 vaccine. In my opinion under this new scenario would
be a world priority to vaccinate in 1st term the whole population
in countries in which actually there is presence of the avian influenza
virus (some African and south Asian countries). The vaccine is the
best tool to cut the transmission of the virus among humans and therefore
the chance of infecting birds.
-
- 2. The laboratory surveillance should also be intensified
in these countries: for avian influenza virus in birds and farm workers
and for A(H1N1)2009 virus in general population and farm workers.
This strategy forces us to train the local laboratories and give
them the equipment required for a local laboratory surveillance and
confirmation.
-
- 3. Educational campaigns should be made in these countries
for all public, especially to bird's farm workers and small home
business. Attention must be provided to universal precaution to avoid
infections from birds or to infect birds during work. The workers
should be trained in keeping alert about bird's behavior changes.
We must keep in mind that the human strain A(H1N1)2009 seem to have
mild symptoms in birds (at least in turkeys). These decisions imply
to postpone actual interest of countries to use the available vaccine
to redirect the benefit to some low income countries. So we are talking
about vaccine that should be provided free of charge for the majority
of this countries. Of course I think that it represents an inversion
for the rest of the world. (keep in mind that the lethality of avian
influenza is close to 50 per cent) and a matter of justice for people
in major risk.
-
- -- Julio Garcia Moreno MD, MSc Head, Biomedical
Department Instituto de Salud FAblica de Chile <mailto:jgarcia@ispch.cl>jgarcia@ispch.cl
-
- ProMED-mail wishes to thank Dr Garcia for the reports
of the virus circulating in the turkeys. - Mod.TG
-
-
- ******
-
-
- H1N1 Flu In Turkeys May Spread
-
- Date: 27 Aug 2009 Source: FAO http://www.fao.org/news/story/en/item/29532/icode/
-
-
- The detection of an H1N1 virus in turkeys in Chile raises
concern that poultry farms elsewhere in the world could also become
infected with the pandemic flu virus currently circulating in humans,
the Food and Agriculture Organization of the United Nations (FAO)
said today.
-
- Chilean authorities reported on 20 Aug 2009 that the
pandemic H1N1/2009 virus was present in turkeys in 2 farms near the
seaport of Valparaiso, Chile. The flu strain found in the poultry
flocks is identical to the H1N1/2009 pandemic strain currently circulating
among human populations around the world.
-
- No threat to humans
-
- -------------------
-
- "However, the discovery of the virus in turkeys
does not pose any immediate threat to human health and turkey meat
can still be sold commercially following veterinary inspection and
hygienic processing. The reaction of the Chilean authorities to the
discovery of H1N1 in turkeys, namely prompt reporting to international
organizations, establishing a temporary quarantine, and the decision
to allow infected birds to recover rather than culling them is scientifically
sound," said FAO's interim chief veterinary officer, Juan Lubroth.
Once the sick birds have recovered, safe production and processing
can continue. They do not pose a threat to the food chain,"
said Lubroth.
-
- Disease monitoring
-
- The current H1N1 virus strain is a mixture of human,
pig and bird genes and has proved to be very contagious but no more
deadly than common seasonal flu viruses. However, it could theoretically
become more dangerous if it adds virulence by combining with H5N1,
commonly known as avian flu, which is far more deadly but harder
to pass along among humans.
-
- "Chile does not have H5N1 flu. In South East Asia,
where there is a lot of the virus circulating in poultry, the introduction
of H1N1 in these populations would be of a greater concern,"
said Lubroth.
-
- This is one reason why the FAO encourages improved monitoring
of health among animals and ensuring that hygienic and good farming
practice guidelines are followed, including protecting farm workers
if animals are sick and not allowing sick workers near animals.
-
- "We must monitor the situation in animals more closely
and strengthen veterinary services in poor and in-transition countries.
They need adequate diagnostic capability and competent and suitably
resourced field teams that can respond to emergency needs,"
Lubroth said.
-
- This phenomenon is called genetic reassortment or recombination
which may happen in case of simultaneous viral infections of any
of the hosts.
-
- This is now the 4th country that is investigating the
spill-over of H1N1/2009 virus from farm workers showing flu-like
illness to animals, with swine becoming infected in Canada, Argentina
and, most recently, Australia.
-
- Even though the clinical infections in pigs and turkeys
so far observed have been generally mild, it is important to bear
in mind that the establishment of pandemic H1N1 virus in pig and
poultry farms has the potential to bring about negative economic
consequences such as trade related restrictions and misguided perceptions
of the quality and safety of meat products, according to FAO.
-
- The emergence of new influenza virus strains capable
of affecting humans and domestic animals remains a broader, more
general concern that is being closely monitored by the FAO, the World
Organisation for Animal Health (OIE), and the World Health Organization
(WHO).
-
- communicated by ProMED-mail rapporteur Mary Marshall
-
-
- 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
new website: http://drpdoyle.tripod.com/ Zhan le Devlesa tai sastimasa
Go with God and in Good Health
|
