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PB2 E627K has been reported in the Netherlands in two patients, right on cue. This is a SERIOUS development.

INFLUENZA PANDEMIC (H1N1) 2009 (58): THE NETHERLANDS, PB2 MUTATION
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A ProMED-mail post
<http://www.promedmail.org>
ProMED-mail is a program of the
International Society for Infectious Diseases
<http://www.isid.org>

Date: Mon 28 Sep 2009
From: Marion Koopmans
<Marion.Koopmans@rivm.nl>


We would like to report 2 patients in The Netherlands, diagnosed with
influenza pandemic A(H1N1) 2009 virus infection that had a mutation (E627K)
in the basic polymerase 2 (PB2) protein. This mutation has previously been
associated with increased efficiency of replication and possible virulence
changes in other influenza A viruses.

The investigation identified a specific geographic region in the north of
The Netherlands as the place where viruses with the same genetic background
have circulated between mid July and mid August [2009]. No other cases
carrying the PB2 mutation have been identified.

On 15 Sep 2009, the 1st influenza A(H1N1)v virus with a glutamic acid to
lysine mutation at position 627 (E627K) in PB2 was identified through
routine sequence analysis of clinical samples from a diabetic patient
infected with A(H1N1)v virus. The 1st day of illness was on 9 Aug 2009,
when the patient was vacationing on one of the West Frisian Islands in the
wetlands north of The Netherlands (Waddenzee). He had a relatively mild
course of illness. Subsequent retrospective tracing of geographically
linked A(H1N1)v cases from the national databases led to the identification
of 24 additional A(H1N1)v confirmed cases throughout the country that had
stayed on the same popular holiday island during July and August. Sequence
analysis of 12/24 clinical specimen available at the institute identified
10 A(H1N1)v viruses that clustered with the virus obtained from the
diabetic index patient based on unique mutations in the NA gene and PB2
gene. Only one of these had the PB2 E627K mutation. This virus was isolated
from a family contact of an adolescent girl who returned from a one-week
stay on the same island on Mon 20 Jul 2009 with high fever and coughing.
This girl had been camping with a group of 16 boys and 8 girls that shared
2 tents. Almost all members of this group reportedly had been ill, and
influenza A(H1N1)v infection had been diagnosed in 2 other persons
belonging to the same camp. The girl was ill for a week, with full recovery
after 2 weeks. Our 2nd case with a virus shedding carrying the PB2 mutation
is the younger sister and became ill on Thu 23 Jul 2009. She was treated
with oseltamivir and recovered fully after one week. Both parents remained
free from symptoms.

As the mutations were identified more than one month after initial
detection, no further contact investigations were done. Municipal health
services were informed about the local disease activity. Since 15 Aug 2009,
mild influenza cases are no longer notifiable in The Netherlands, so we
have no information on possible onward transmission. No clusters of illness
(for example, from schools) were reported in the health regions involved
(including the island), and surveillance data from a national
physician-based sentinel network showed low ILI activity for the
Netherlands. Samples from 22 patients hospitalized with influenza A(H1N1)
in July and August did not have the PB2 mutation.

PB2 627K is consistently found in human influenza A viruses, but rarely in
avian-derived viruses. The E627K mutation may result in enhanced virus
replication efficiency in humans, possibly by adjustment to host body
temperature or cellular cofactors, and has previously been shown to be
associated with fatal cases of HPAI H5N1 and H7N7 virus infection in
humans. Until now, A(H1N1)v viruses with Influenza pandemic (H1N1) 2009
(57): in PB2 have not been reported, and the clinical and epidemiological
relevance of our finding remains unclear.

Preliminary experiments in ferrets using reverse genetics-derived new
influenza A(H1N1)v viruses with the E267K mutation in PB2 did not indicate
increased shedding, virulence or transmissibility. Further experiments as
well as increased molecular surveillance to monitor the situation are ongoing.

[byline: M Jonges 1, A Meijer 1, J van Steenbergen 2, T Oomen 2, H Vennema
1, J Spaargaren 3, Kampman 4, P van der Tas 5, R Ter Schegget 6, Wim van
der Hoek 7, J Tjie 8, R Benne 9, Sander Herfst 10, Salin Chutinimitkul 10,
Ab Osterhaus 10, Ron Fouchier 10, Marion Koopmans 1, 10.
At:
1 National Institute for Public Health and the Environment, Centre for
Infectious Disease Control, PO Box 1, 3720 BA, Bilthoven, The Netherlands
2 Preparedness and response unit, Center for infectious disease control,
Bilthoven
3 Laboratory for Microbiology, Enschede
4 Municipal Health Service, Twente
5 Municipal Health Service, Friesland
6 Municipal health service, Brabant
7 Epidemiology and surveillance unit, Center for infectious disease
control, Bilthoven
8 Microbiological laboratory Veldhoven
9 Laboratory for infectious diseases, Groningen
10 Laboratory for Virology, ErasmusMC, Rotterdam]

--
communicated by:
Marion Koopmans
Chief of Virology
Laboratory for Infectious Diseases and Screening, Center for Infectious
Disease Control
National Institute of Public Health
The Netherlands
<Marion.Koopmans@rivm.nl>

[ProMED-mail thanks Dr Koopmans and colleagues for providing this
interesting information recording the detection of the same E267K mutation
in the basic polymerase 2 (PB2) protein of 2 independent isolates of
A(H1N1)v in the north of The Netherlands. The functional relevance of this
mutation remains to be determined. - Mod.CP]

[see also:
Influenza pandemic (H1N1) 2009 (57): case counts 20090925.3367
Influenza pandemic (H1N1) 2009 (56): antiviral resistance risk 20090925.3363
Influenza pandemic (H1N1) 2009 (55): vaccine formulation 20090925.3359
Influenza pandemic (H1N1) 2009 (54): vaccine availability 20090921.3325
Influenza pandemic (H1N1) 2009 (53): vaccine donation 20090919.3290
Influenza pandemic (H1N1) 2009 (52): WHO update 66 20090918.3272
Influenza pandemic (H1N1) 2009 (51): antibody deficiency 20090917.3261
Influenza pandemic (H1N1) 2009 (50): oseltamivir-resistance 20090917.3260
Influenza pandemic (H1N1) 2009 (40): global update 20090906.3138
Influenza pandemic (H1N1) 2009 (30): assumptions 20090813.2879
Influenza pandemic (H1N1) 2009 (20): Peru, 33 percent asymptomatic
20090730.2668
Influenza pandemic (H1N1) 2009 (10): vaccine 20090720.2577
Influenza pandemic (H1N1) 2009 - Viet Nam: patient data 20090708.2450]

....................cp/ejp/sh

http://www.recombinomics.com/News/06180 ... E627K.html

E627K Acquisition in Swine H1N1 Raises Pandemic Concerns
Recombinomics Commentary 11:37
June 18, 2009


The recently released PB2 sequence from a patient (22F) in Shanghai (see updated map) contains E627K. This is the first reported acquisition of this change, which is present in virtually all human influenza A isolates, including the pandemic strain from 1918.

The current isolate, A/Shanghai/71T/2009, was collected May 31, 2009 and the sequence was deposited at Genbank on June 10, 2009. The isolate is closely related to the swine H1N1 currently spreading worldwide, and all positions upstream from E627K match the consensus sequence, indicating the E627K was not acquired through reassortment with human PB2 or other H1N1 viruses that were not closely related to the swine H1N1 circulating in the human population...............

Dr. Niman,

What is the implication of this E627K mutation on the efficacy of the current vaccine, if any?

Could this be the harbinger of a more deadly 3rd wave sometime during January-February in the northern hemisphere?

Thanks.

The vaccine is directed against H and N, so changes in PB2 will have no effect (although there also appears to be changes in N).

The concern is that PB2 will create a much higher viral load, which could have catestrophic consequences (including high levels in the upper and lower repiratory tract due to mixtures of virus with and without E627K).

Commentary

http://www.recombinomics.com/News/09290 ... lands.html

Commentary

http://www.recombinomics.com/News/09290 ... 7K_SS.html

Dr Niman, when will we know more about this. How will this affect us in the winter, if at all? So are there ongoing studies to see if this going to affect the vaccine.
In other words, what can we do or should we wait for further studies to be concluded.

The E627K is in PB2, which is not a vaccine target (the vaccine only targets H and N). However, the true level of E627K remains open and the latest sequences should help focus efforts to see how widespread E627K is. Its role in the rapid spread or viral load for pandemic H1N1 is still open, and could significantly affect spread and virulence.

Right now the vaccine against pandemic H1N1 should offer protection, assuming recent outbreaks are similar to published sequences.

This virus is something to avoid, and keeping schools open when absentee rates are in the double digits is NOT a good idea Similarly, assumptions that future infections will be as mild as past infections may not be justified.

Italian media report (translation via Google):

IN HOLLAND 2 patients with mutations VIRUS
(AGI) - Londra, 29 set. (AGI) - London, September 29 -

In two Dutch patients suffering from influenza and pandemic 'revealed a new mutation, usually associated with increased virus replication and its other possible changes of the virus. You can 'read in a report of the International Society for Infectious Diseases: the mutation, called E627k, acts on the PB2 protein. "This protein is' normally present in the influenza A virus, but it 'the first time that the specific mutation is reported," you can' read the report. "The mutation could result in greater efficiency of virus replication in humans due to changes in body temperature of the host." Furthermore, this mutation and 'in the past been associated with fatal cases of human infections of bird virus H5N1 and H7N7. The two cases were identified with the routine analysis on specific regions of the north of Holland. Were not revealed additional mutations of the PB2 protein in all other patients analyzed. "Since 'the mutation and' identified in the most 'original analysis of one month, were not carried out further research on patients," write the authors of the report. "Since 'from August 2009 there have been more' cases of medium importance of pandemic influenza in the Netherlands, we have no information about possible transmission of the mutation. The clinical and epidemiological implications of our findings are still unclear.