• FluTrackers.com Inc. does not provide medical advice. Information on this web site is collected from various internet resources, and the FluTrackers board of directors makes no warranty to the safety, efficacy, correctness or completeness of the information posted on this site by any author or poster. The information collated here is for instructional and/or discussion purposes only and is NOT intended to diagnose or treat any disease, illness, or other medical condition. Every individual reader or poster should seek advice from their personal physician/healthcare practitioner before considering or using any interventions that are discussed on this website. By continuing to access this website you agree to consult your personal physican before using any interventions posted on this website, and you agree to hold harmless FluTrackers.com Inc., the board of directors, the members, and all authors and posters for any effects from use of any medication, supplement, vitamin or other substance, device, intervention, etc. mentioned in posts on this website, or other internet venues referenced in posts on this website.
  • We are not asking for any donations. Do not donate to any entity who says they are raising funds for us.

Brazil finds new strain of H1N1 virus - NOT

Re: Brazil finds new strain of H1N1 virus - NOT

I think the facts are that we have precisely been studying this strain since mid-April. The Sao Paulo isolate is not a new strain. As soon as it was released to GenBank, it was found to be identical to a large majority of all the other Swine Flu isolates using a variety of tools.

The disjunct is Brazilian scientists shooting from the hip and causing un-needed consternation. I would respectfully suggest that they retract their media statements.


What officially defines a new strain? Do the differences in the MP segment qualify, or were they unwarranted in using the terminology?

Genuinely curious here, I'm not trying to pick a fight.
 
Re: Brazil finds new strain of H1N1 virus - NOT

From Virology blog:

Brazilian influenza H1N1 isolate is not novel


There is nothing novel about this Brazilian isolate. Comparison of the amino acid sequence of the HA protein of A/Sao Paulo/1454/H1N1 with those of other isolates of the current pandemic strain reveals no alterations in the HA protein which would allow the virus to infect new hosts. The HA protein of this virus and many other 2009 H1N1 isolates are identical. The few amino acid differences with other 2009 H1N1 isolates are in areas that would not be expected to influence antigenicity or host range.

I?ll give the journalists the benefit of doubt: perhaps they misinterpreted the statements of the Brazilian scientist. But they should have confirmed their story with a virologist. They would have learned within a few minutes that there is nothing novel about A/Sao Paulo/1454/2009 (H1N1).

http://www.virology.ws/2009/06/17/brazilian-influenza-h1n1-isolate-is-not-novel/

credits Fla_Medic
 
Re: Brazil finds new strain of H1N1 virus - NOT

Thank you,

That's the insight I was talking about. This is how to dismiss something. It shows that the individual thought it out and has knowledge in the topic being discussed.

I hope you keep lurking and commenting here, we need more insight like this.
There were ZERO gaps because there were ZERO differences.
 
Re: Brazil finds new strain of H1N1 virus - NOT

There were ZERO gaps because there were ZERO differences.

Blast results show MP gene has 1790 vs 1814 for a 99% match compared to A/Calif?rnia/04/H1N1.

Blast search GQ250156 and query 250 results showing to see them.


What is the official definition for a new strain, does this qualify?
 
Re: Brazil finds new strain of H1N1 virus - NOT

What officially defines a new strain? Do the differences in the MP segment qualify, or were they unwarranted in using the terminology?

Genuinely curious here, I'm not trying to pick a fight.

New strains are generally based on differences in the HA and NA segments since MP is highly conserved both within viral subtypes and across subtypes. There is no formal method of which I am aware for naming strains, therefore, I have relied on the CDC's categorizations of five main variants as it relates to Swine Flu.

Having said that, if there are antigenic differences between isolates that would affect vaccine efficacy, then clearly those are separate strains, without regard to the number of amino acid differences in the HA and NA segments.
 
Re: Brazil finds new strain of H1N1 virus - NOT

New strains are generally based on differences in the HA and NA segments since MP is highly conserved both within viral subtypes and across subtypes. There is no formal method of which I am aware for naming strains, therefore, I have relied on the CDC's categorizations of five main variants as it relates to Swine Flu.

Having said that, if there are antigenic differences between isolates that would affect vaccine efficacy, then clearly those are separate strains, without regard to the number of amino acid differences in the HA and NA segments.


That makes sense, is it possibly a different variant then?
 
Re: Brazil finds new strain of H1N1 virus - NOT

Ok folks,

Thank you for all the information here :applause: :tiphat:

I posted the original story at FT, as I live in Brazil and this story were at the more important news on the day I thought it was a good idea to post here... I'm not from the medical or biological field, so I'm completely clueless when I read something like that in the news and you did a great job showing why it was not news... and we should not be warned by it.

As long as I know (by web search) Brazil is trying to do a vaccine, I've already posted about this earlier. Maybe this story is just to show the public they are working on that... as "making news". Well, this is very common in here, politics runs everything and that's why being at FT is great. We can have more accurate information about it.

thanks all. Keep on the good job.
 
Re: Brazil finds new strain of H1N1 virus - NOT

Blast results show MP gene has 1790 vs 1814 for a 99% match compared to A/Calif?rnia/04/H1N1.

Blast search GQ250156 and query 250 results showing to see them.


What is the official definition for a new strain, does this qualify?

There are zero amino acid differences between Sao Paulo and California/04, therefore, there are no antigentic differences between the two viruses. If you based strain definition on MP alone, the two viruses would be one strain.
 
Re: Brazil finds new strain of H1N1 virus - NOT

There are zero amino acid differences between Sao Paulo and California/04, therefore, there are no antigentic differences between the two viruses. If you based strain definition on MP alone, the two viruses would be one strain.


Got it, so there has to be an antigenic difference or amino acid difference for it to be a new strain.

-Thanks
 
Re: Brazil finds new strain of H1N1 virus - NOT

Got it, so there has to be an antigenic difference or amino acid difference for it to be a new strain.

-Thanks
No. New strains are defined by phylogenetic analysis (of NUCLEOTIDES).
 
Re: Brazil finds new strain of H1N1 virus - NOT

That makes sense, is it possibly a different variant then?

Based on the limited information available (only 2 of the 8 gene segments) it falls in either i, ii or iii according to the CDC research paper describing variants. That covers 60% of all the Swine Flu isolates available. And, since the patient came from Mexico and then developed symptoms, there are Mexican isolates in each of those three variants.

With the PA, NP and NS segments from Sao Paulo, we can narrow that down to just one variant.
 
Re: Brazil finds new strain of H1N1 virus - NOT

the virus(substrain) is fishy, though.
It has 5 of the 11 Cancun markers, both strains
were in Mexico at that time.
Both were exported. But there are no intermediates
as is usual. So, suddenly 6 new mutations ?

Also, 3 of the 5 markers were seen in Korea,Japan later
and now these 3 plus the 11-5=6 others in Shandong/71T
 
Re: Brazil finds new strain of H1N1 virus - NOT

the virus(substrain) is fishy, though.
It has 5 of the 11 Cancun markers, both strains
were in Mexico at that time.
Both were exported. But there are no intermediates
as is usual. So, suddenly 6 new mutations ?

Also, 3 of the 5 markers were seen in Korea,Japan later
and now these 3 plus the 11-5=6 others in Shandong/71T

There are zero amino acid differences between Sao Paulo and A/Mexico/4115, an isolate collected in the first week of April.
 
Re: Brazil finds new strain of H1N1 virus - NOT

Thank you,

That's the insight I was talking about. This is how to dismiss something. It shows that the individual thought it out and has knowledge in the topic being discussed.

I hope you keep lurking and commenting here, we need more insight like this.

While possibly true, my information is based on a somewhat vague memory of the underpinnings of BLAST. Dr. Niman and/or others probably have a better grasp on the meaning. Especially since the final BLAST number was perfectly matched. I could be wrong in the sense that one number difference might account for slightly different sequences. So for example, 3608 for all could be a 100% match, where 3608 and 3607 could technically mean a difference in the sequence, but not in any significance. In which case the researchers in Brazil would be technically right, but not scientifically right as to statistically/functionally/structurally there being any real difference. (assuming the second example, which is not the case)

In which case they might win the battle, but not the war. Either way, pie in the face. However, if the number derived from BLAST is computing on some calculation that accounts for "gaps" where the sequence is not identical...(ps gap calculations can be tweaked as well from what I remember) then the differences are accounted for in the calculation showing no difference in the scoring. I will say that most are clear that the BLAST method accounts accurately for the errors, gaps, etc. and takes into consideration the different AA changes and how they have an influence at different positions. (although I think that using the protein AA's is the ideal situation to eliminate things like wobble etc.) So if the sequences from Brazil are AA's then there may be a better comparison. If they busted it down to the A's, T's, G's, and C's then they may find some slight difference...even though it encodes a particular AA regardless. The point is the AA's are the same then it comes down to gaps and stuff, and the statistics/accounting for differences. BLAST is well accepted for sure!

I get what you mean though, just a little more verifiable information behind the methods and how they disprove the conclusion that the "Sao strain" is really different.
 
Last edited:
Re: Brazil finds new strain of H1N1 virus - NOT

There are zero amino acid differences between Sao Paulo and A/Mexico/4115, an isolate collected in the first week of April.
I believe GS has his threads mixed up and is discussing the Shanghai sequence on the Brazilian thread.
 
Re: Brazil finds new strain of H1N1 virus - NOT

the virus(substrain) is fishy, though.
It has 5 of the 11 Cancun markers, both strains
were in Mexico at that time.
Both were exported. But there are no intermediates
as is usual. So, suddenly 6 new mutations ?

Also, 3 of the 5 markers were seen in Korea,Japan later
and now these 3 plus the 11-5=6 others in Shandong/71T
I believe the above post was meant for the thread discussing the Shangai isolate (with PB2 E627K).

The isolate from Brazil has NO distinctive markers.
 
Re: Brazil finds new strain of H1N1 virus - NOT

but nucleotide-difference C1408T(4) , synonymous.
But not T658A(4) , so that makes it a likely member of
the Mexico-City-substrain [e.g. Mexico/4604] characterized by:
C1408T(4),G298A(5),G1143A(5),G316A(6),A742G(6)
 
Re: Brazil finds new strain of H1N1 virus - NOT

Just found this, buried in yesterday news... modified at 7pm it sounds to me that the "new strain stuff" was a reporter stuff, not from the researcher... anyways... here it goes...

***WARNING GOOGLE TRANSLATION ***

Tuesday, June 16, 2009, 13:17 | Online

Adolfo Lutz isolated variant of the H1N1 virus that arrived in Brazil

The sequencing will contribute to the production of influenza vaccine and evaluation of response to antiviral

Alexandre Gon?alves, O Estado de S. Paulo

Adolfo Lutz isolated variant of the H1N1 virus that arrived in Brazil

S?O PAULO - The Institute Adolfo Lutz performed the complete sequence for the first time in Brazil, two key genes of the virus A (H1N1). The first patient diagnosed with swine flu in S?o Paulo provided the samples of the micro-organism. When compared with the first sequence performed in California, the scientists identified small changes. However, the rate of similarity between the viruses decoded in Brazil and the United States is still more than 99.5%. Researchers find good news is that the virus has changed so little.

The announcement was made yesterday in the auditorium of the Institute of Infectious Diseases Emilio Ribas, Sao Paulo. The hospital has received, on April 24, the traveler of 26 years who brought the virus from Mexico now sequenced by scientists. "We still do not know what are the impacts of these variations in the action of the virus," says Cec?lia Luiza Sim?es dos Santos, biologist of the Adolfo Lutz.

The researchers chose to sequence two genes: the MP gene - which encodes the matrix protein M1 and M2, more abundant in the composition of the virus - and the HA gene - which produces the hemagglutinin protein, responsible for the invasion of the host cell.

Mutations occurred in the HA gene. "Fortunately, not identified in any known active site of the protein," Cec?lia exception. The antibodies that the body produces to fight the virus acts on the active site of the molecule. Therefore, any significant change in this region of the protein can render vaccines ineffective. "The vaccines in development will work," notes the scientist.

The M gene sequence is identical to the virus Californian. As its American parent, contains a label that indicates resistance to a class of antivirals called amantadine.



"The next step is to sequence the gene encoding neuranimidase" provides Cecilia. The substance is responsible for releasing the virus after infection of cells to undertake new contagion. Oseltamivir phosphate - considered one of the main weapons against the new influenza - acting on neuranimidase and therefore a mutation in this protein can decrease the effectiveness of the remedy. The flu virus has eight genes.



Scientists compared the sequenced strain of the virus in S?o Paulo the dozens of already registered in the database of the National Center for Biotechnology Information (NCBI, U.S.), USA. "There was much similarity with strains from Italy, Texas, China and Korea," says Cecilia. "None was identical, but it was only a preliminary analysis."



A month ago, researchers from the Instituto Oswaldo Cruz (IOC-Fiocruz) had deposited in the NCBI database of partial sequences of the M gene obtained from three different patients: two in Rio de Janeiro and one in Minas Gerais. About 80% of M1 and M2 proteins were decoded at the time.




"In September, a meeting at the World Health Organization (WHO) to analyze the strains sequenced in the southern hemisphere," says the virology of the Adolfo Lutz, Terezinha Maria de Paiva. "Based on the data, we identified the need to develop a vaccine other than the northern hemisphere, for example."



(Extended with more information to 19h53)

Source: http://www.estadao.com.br/noticias/...asileira-do-virus-da-gripe-suina,388181,0.htm


__________

Original:

ter?a-feira, 16 de junho de 2009, 13:17 | Online

Adolfo Lutz isola variante do v?rus H1N1 que chegou ao Brasil

O sequenciamento vai contribuir para a produ??o da vacina contra a gripe e avalia??o da resposta aos antivirais

Alexandre Gon?alves, de O Estado de S. Paulo

Adolfo Lutz isola variante do v?rus H1N1 que chegou ao Brasil

S?O PAULO - O Instituto Adolfo Lutz realizou o sequenciamento completo, pela primeira vez no Pa?s, de dois genes importantes do v?rus A(H1N1). O primeiro paciente diagnosticado com a gripe su?na em S?o Paulo forneceu as amostras do micro-organismo. Ao comparar com os primeiros sequenciamentos realizados na Calif?rnia, os cientistas identificaram pequenas muta??es. Contudo, a taxa de similaridade entre os v?rus decodificados no Brasil e nos Estados Unidos ainda ? superior a 99,5%. Pesquisadores consideram uma boa not?cia que o v?rus tenha se modificado t?o pouco.

O an?ncio foi feito ontem no audit?rio do Instituto de Infectologia Em?lio Ribas, em S?o Paulo. O hospital recebeu, no dia 24 de abril, o viajante de 26 anos que trazia do M?xico o v?rus agora sequenciado pelos cientistas. ?Ainda n?o sabemos quais s?o os impactos dessas varia??es na a??o do v?rus?, afirma Cec?lia Luiza Sim?es dos Santos, bi?loga do Adolfo Lutz.

Os pesquisadores escolheram dois genes para sequenciar: o gene MP - que codifica as prote?nas da matriz M1 e M2, mais abundantes na composi??o do v?rus - e o gene HA - que produz a prote?na hemaglutinina, respons?vel pela invas?o da c?lula hospedeira.

As muta??es ocorreram no gene HA. ?Felizmente, n?o identificamos nenhuma no chamado s?tio ativo da prote?na?, ressalva Cec?lia. Os anticorpos que o corpo humano produz para combater o v?rus agem sobre o s?tio ativo da mol?cula. Por isso, qualquer muta??o significativa nessa regi?o da prote?na pode tornar vacinas ineficazes. ?As vacinas em fase de desenvolvimento dever?o funcionar?, aponta a cientista.

O gene M sequenciado ? id?ntico ao do v?rus californiano. Como seu parente americano, cont?m um marcador que indica resist?ncia a uma classe de antivirais chamada amantadina.



?O pr?ximo passo ? sequenciar o gene que codifica a neuranimidase?, prev? Cec?lia. A subst?ncia ? respons?vel por libertar os v?rus das c?lulas depois da infec??o para que realizem novos cont?gios. O fosfato de oseltamivir - considerado uma das principais armas contra a nova gripe - age sobre a neuranimidase e, por isso, uma muta??o nesta prote?na pode diminuir a efic?cia do rem?dio. O v?rus da gripe possui oito genes.



Os cientistas compararam a estirpe do v?rus sequenciado em S?o Paulo a algumas dezenas das j? cadastradas na base de dados do Centro Nacional de Informa??o Biotecnol?gica (NCBI, em ingl?s), nos Estados Unidos. ?Havia muita semelhan?a com estirpes da It?lia, Texas, China e Coreia?, afirma Cec?lia. ?Nenhuma era id?ntica, mas foi apenas uma an?lise preliminar.?



H? um m?s, pesquisadores do Instituto Oswaldo Cruz (IOC-Fiocruz) j? tinham depositado no banco de dados do NCBI sequenciamentos parciais do gene M obtidos de tr?s pacientes diferentes: dois no Rio de Janeiro e um em Minas Gerais. Cerca de 80% das prote?nas M1 e M2 foram decodificadas na ocasi?o.



?Em setembro, haver? uma reuni?o na Organiza??o Mundial da Sa?de (OMS) para analisar as estirpes sequenciadas no hemisf?rio sul?, afirma a virologista do Adolfo Lutz, Terezinha Maria de Paiva. ?Com base nos dados, podemos identificar a necessidade de desenvolver uma vacina diferente do hemisf?rio norte, por exemplo.?



(Ampliada com mais informa??es ?s 19h53)

Fonte: http://www.estadao.com.br/noticias/...asileira-do-virus-da-gripe-suina,388181,0.htm
 
Re: Brazil finds new strain of H1N1 virus - NOT

While possibly true, my information is based on a somewhat vague memory of the underpinnings of BLAST. Dr. Niman and/or others probably have a better grasp on the meaning. Especially since the final BLAST number was perfectly matched. I could be wrong in the sense that one number difference might account for slightly different sequences. So for example, 3608 for all could be a 100% match, where 3608 and 3607 could technically mean a difference in the sequence, but not in any significance. In which case the researchers in Brazil would be technically right, but not scientifically right as to statistically/functionally/structurally there being any real difference.

In which case they might win the battle, but not the war. Either way, pie in the face.

I get what you mean though, just a little more verifiable information behind the methods and how they disprove the conclusion that the "Sao strain" is really different.
The HA sequence from Brazil has ZERO distinctive markers. Every position is found in at least 100 prior H1N1 swine sequences. Sequences that have one or two differences are because those sequences have something distinctive. The Brazil sequence EXACTLY matches the consensus sequence at ALL 1701 positions (i.e. 1701/1701 MATCH).
 
Re: Brazil finds new strain of H1N1 virus - NOT

ALL 1701 nucleotide positions are IDENTICAL to more than 100 H1N1 public sequences at Genbank (no gaps required - there are ZERO differences). Gaps are used for sequences that have divered over centuries, not a few weeks.



Hence Bioinformatics.....often the comparison of ancestors over centuries. The protein of today and how well it is conserved from first organisms. Makes sense that there isn't likely to be much drift in just a few short years or in this case months.

Thanks!
 
Back
Top