• 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.

Madagascar: Vaccine-derived polioviruses detected in asymptomatic children

alert

Senior Moderator
http://promedmail.org/pls/apex/f?p=..._BACK_PAGE,F2400_P1001_PUB_MAIL_ID:1000,90759

Archive Number 20111020.3128
Published Date 20-OCT-2011
Subject PRO/EDR> Poliomyelitis, vaccine derived - Madagascar: (TL) RFI

POLIOMYELITIS, VACCINE DERIVED - MADAGASCAR: (TOLIARA) REQUEST FOR
INFORMATION
******************************************************************************
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: Wed 19 Oct 2011
Source: Linfo Reunion [in French, trans., edited]
<http://www.linfo.re/-Societe,402-/Madagascar-l-epidemie-de-poliomyelite-reapparait>


Madagascar: the epidemic of polio reappears
-------------------------------------------
While no cases of polio have been detected in Madagascar since the
late 1990s, the authorities announced that they had identified 6 new
cases in the south of the country, raising fears of a new resurgence
of the epidemic of polio. The low immunization rates combined with the
health problems and malnutrition may well contribute to a reoccurrence
of this disease.

While polio has virtually disappeared from the Big Island since 1997,
the Ministry of Health said it had identified 6 cases [of polio] in
unvaccinated children in the remote areas of Fort Dauphin and Tulear.
A study conducted by the Pasteur Institute has indicated that the
virus involved in these cases is derived from a vaccine virus and
therefore would be less virulent causing a slight paralysis, while the
wild-type virus usually causes severe paralysis. [This is not correct
as vaccine derived poliomyelitis cases do present with significant
paralytic disease. - Mod.MPP]

However, those cases associated with poliovirus vaccine derived from
making the eradication of polio more complex, according to scientists,
especially in the wild south of Madagascar, the location of the new
epidemic, where they are struggling with challenges related to the
health and sanitation including malnutrition. This compounds the
problem of low vaccination coverages.

A report released by the Ministry of Health in 2010 showed that only
70 per cent of Malagasy children were vaccinated against polio and
this nationwide rate includes areas in the south, the most vulnerable
zones on the large island.

An epidemiological investigation will permit identifying if there are
other cases [of circulating vaccine derived poliovirus (cVDPV)
paralytic disease] in other regions of the country. But in the
meantime, a mass vaccination campaign was launched beginning Monday,
[17 Oct 2011] in order to increase the immunity level [against
poliovirus infection] of the population, mainly in children.

--
communicated by:
ProMED-mail from HealthMap alerts
<promed@promedmail.org>

[Madagascar had identified circulating vaccine derived poliovirus
(cVDPV) associated paralytic disease in 2001-2002. At that time there
were 5 cases of type 2 cVDPV associated cases reported from the same
province -- Toliara -- where these current cases have been identified.
The 1st case had date of onset in 2001 and was a resident of Toliara
(Tulear). The other 4 cases with dates of onset in March and April
2002 were in a rural village about 400 km (250 mi) from Toliara. None
of those cases had a history of having completed a 3 dose series of
polio vaccination. According to genetic studies on the involved
viruses in the cases and contacts, the cases from the 2 different
areas represented 2 genetically distinct, independent cVDPV lineages.
At that time, the OPV (oral polio vaccine) coverage in Madagascar was
less than 50 per cent countrywide.

According to the Polio Eradication Initiative website, in 2005, there
were 3 additional type 2 VDPV (vaccine derived polioviruses) cases
identified in the same province (Toliara) as in the 2001-2002 cases
(see Table on cVDPV isolates by
country and VDPV type, 2000-2001
<http://www.polioeradication.org/Dataandmonitoring/Poliothisweek/Circulatingvaccinederivedpoliovirus.aspx>).
Of note, according to Rakoto-Andrianarivelo M et al (see ref 7 below),
in 2005 type 3 or type 2 VDPV was isolated from 5 paralytic cases and
from healthy contacts. The isolated strains were classified into 4
recombinant lineages that showed complex mosaic genomic structures
originating from different vaccine strain serotypes and probably from
human enterovirus C (HEV-C) species. Genetic relatedness could be
observed among these 4 lineages. At that time, the OPV coverage in the
affected province was less than 80 per cent.

Given the history of 2 prior outbreaks of paralytic disease associated
with cVDPVs in the same province (Toliara), it would be of interest to
see the phylogenetic trees of these current isolates compared with
those involved in the outbreaks in 2001/2002 and 2005 -- one wonders
if there has been continued circulation of the VDPV lineages
associated with the prior outbreaks or if repeated lapses in OPV
coverages have led to the emergence of different lineages of VDPVs in
the region.

Fort Dauphin is now known as Tolanaro or Tolagnaro. it is the capital
of the Anosy Region and the Tolanaro district, located in the extreme
south of the country in the province of Toliara. Tulear is now known
as Toliara and is the capital of the Atsimo-Andrefana region, in
province of Toliara (from Wikipedia information on administrative
divisions of Madagascar, <http://en.wikipedia.org/wiki/Madagascar>.)

For a map of Madagascar showing provinces, see
<http://www.madbookings.com/madagascar/maps/madagascar_political_map.jpg>.
For the interactive HealthMap/ProMED-mail map of Toliara province, see
<http://healthmap.org/r/1lUh>. For a map of the location of the 2005
cVDPV cases in Madagascar, see ref 7 below, Figure 1, available at
<http://jid.oxfordjournals.org/content/197/10/1427/F1.expansion.html>.

References
----------
1. Kew OM, Wright PF, Agol VI, et al. Circulating vaccine-derived
polioviruses: current state of knowledge. Bull World Health Organ.
2004 Jan; 82(1):16-23. Epub 2004 Feb 26 (full article available at
<http://www.scielosp.org/scielo.php?pid=S0042-96862004000100006&script=sci_arttext&tlng=es>).
2. Tebbens RJ, Pallansch MA, Kew OM, et al. Risks of paralytic disease
due to wild or vaccine-derived poliovirus after eradication. Risk
Anal. 2006 Dec; 26(6): 1471-505 (full article available at
<http://www.kidrisk.org/images/riskanal26.6.1471.pdf>).
3. Wringe A, Fine PE, Sutter RW, Kew OM. Estimating the extent of
vaccine-derived poliovirus infection. PLoS One. 2008; 3(10): e3433.
Epub 2008 Oct 29 (full article available at
<http://www.plosone.org/article/info:doi/10.1371/journal.pone.0003433>).
4. Centers for Disease Control and Prevention (CDC). Update on
vaccine-derived polioviruses -- worldwide, January 2008-June 2009.
MMWR Morb Mortal Wkly Rep. 2009 Sep 18; 58(36): 1002-6 (full article
available at
<http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5836a3.htm>).
5. CDC. Update on vaccine-derived polioviruses. MMWR Morb Mortal Wkly
Rep. 2006 Oct 13; 55(40); 1093-7 (full article available at
<http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5540a3.htm>).
6. CDC. Update on vaccine-derived polioviruses -- worldwide, July
2009-March 2011. MMWR Morb Mortal Wkly Rep. 2011 Jul 1; 60(25): 846-50
(full article available at
<http://www.cdc.gov/mmwr/preview/mmwrhtml/mm6025a3.htm>).
7. Rakoto-Andrianarivelo M, Gumede N, Jegouic S, et al: Reemergence of
recombinant vaccine-derived poliovirus outbreak in Madagascar. J
Infect Dis. 2008 May 15; 197(10): 1427-35 (full article available at
<http://jid.oxfordjournals.org/content/197/10/1427.long>). - Mod.MPP]
 
Re: Madagascar: Vaccine-derived polio outbreak

Re: Madagascar: Vaccine-derived polio outbreak

Source: http://www.bbc.co.uk/news/world-africa-15415425

22 October 2011 Last updated at 16:10 ET
UN finds polio among Madagascar's children
By Tim Healy BBC News, Antananarivo

An outbreak of polio in three children from the south of Madagascar has raised concerns over a possible resurgence of this crippling disease.

The UN children's fund (Unicef) has called for urgent action to prevent its spread.

Unicef spokesman Daniel Timme says three cases of polio without symptoms have been identified...
 
Re: Madagascar: Vaccine-derived polio outbreak

Re: Madagascar: Vaccine-derived polio outbreak

Source: http://www.bbc.co.uk/news/world-africa-15454479

25 October 2011 Last updated at 14:41 ET
Madagascar: UN denies polio outbreak

The UN children's fund has denied that there has been a polio outbreak in the Indian Ocean island of Madagascar.

It said that its office in Madagascar had issued a statement last week that led to the mistaken belief there had been an outbreak of wild poliovirus.

In fact the last such case was detected on the island in 1997, Unicef said.

The confusion had arisen because vaccine-derived poliovirus had been detected in three healthy children amid an immunisation campaign last week...
 
Re: Madagascar: Vaccine-derived polio outbreak

Re: Madagascar: Vaccine-derived polio outbreak

Unfortunately, that appears to be a denial of what has already been admitted. Pathfinder and the other Francophones have been keeping their thred here:

http://www.flutrackers.com/forum/showthread.php?t=174972

in which at least six individuals have had paralytic illnesses confirmed as due to VDPV, some of which were not vaccinated. So vaccine-derived virus is indeed likely circulating.
 
Re: Madagascar: Vaccine-derived polio outbreak

Re: Madagascar: Vaccine-derived polio outbreak

http://www.promedmail.org/

Published Date: 2011-11-16 13:40:11
Subject: PRO/EDR> Poliomyelitis, vaccine derived - Madagascar (02): (TL), corr.
Archive Number: 20111116.3379

POLIOMYELITIS, VACCINE DERIVED - MADAGASCAR (02): (TOLIARA),
CORRECTION
***********************************************************************

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: Wed 16 Nov 2011From: Jean-Michel Heraud [edited]


[Re: ProMED-mail Poliomyelitis, vaccine derived - Madagascar: (TL) RFI
20111020.3128]
----------------------------------------------------------------------
[The posting dated 20 Oct 2011], suggested that new cases of
poliomyelitis occurred in Madagascar. In fact, to date, there is no
evidence of any case of acute [flaccid] paralysis (AFP) or
poliomyelitis in Madagascar in 2011. The information attributed by the
source (Linfo Reunion [in French, trans., edited]) to the Ministry of
Health of Madagascar is false.

Recently, in 2 districts of the Toliara province (South-West of
Madagascar), 8 polio vaccine viruses including 3 potentially
pathogenic vaccine-derived polioviruses (VDPVs) have been isolated
from asymptomatic children (less than 5 years old) who did not receive
any oral polio vaccine in the 30 days before the samples collection
. 2
of these VDPVs had more than 30 mutations in the VP1 region and one
had 6 mutations. Although these 3 viruses present similar genetic
features, they however clearly differ (no genetic link) from those
isolated in 2001-2002 and in 2005 from patients with acute flaccid
paralysis (poliomyelitis cases). The neuro-pathogenicity of these new
VDPVs is under investigation. It is important to mention that these
results were obtained as part of a research project on human
enteroviruses and not from the national surveillance system of the
acute [flaccid] paralysis (AFP) and poliomyelitis
. This research
program is carried out by the virology unit at the Institut Pasteur
from Madagascar in partnership with the enterovirus biology unit at
the Institut Pasteur in Paris.

Although no evidence of acute flaccid paralysis linked to these new
VDPVs have been demonstrated, their detection in 3 children and their
genetic characteristics strongly suggest that the vaccine coverage
against poliovirus in the region of Toliara (Atsimo Andrefana) is too
low, favoring the circulation and genetic drift of the polio vaccine
strain. In order to respond to the threat of the emergence of an
epidemic strain in the Malagasy population, it is necessary to ensure
high polio vaccine coverage and to continue the monitoring of the
circulation of these VDPVs within the community. To reach these
objectives, the Ministry of Health has planned a campaign of
vaccination in some districts (Atsimo Andrefana, Androy, Anosy, and
Antananarivo) in December [2011] and January 2012].

--
Dr. Jean-Michel HERAUD, Ph.D.
Chief of the Virology Unit,
Director of the NIC
Institut Pasteur de Madagascar
BP 1274
Antananarivo 101 - Madagascar


[ProMED-mail would like to thank Dr Heraud for the detailed
explanation above of the circumstances surrounding the identification
of circulating vaccine derived polioviruses (cVDPV) in Toliara
Madagascar. It is unfortunate that the media presented incorrect
information surrounding these isolates, albeit providing local
incentive to increase vaccination coverages might not be considered a
bad outcome of this error. It will be interesting to learn the results
of the neurovirulence studies on these isolates as this region
(Toliara) has had prior clinical paralytic poliomyelitis cases
associated with cVDPV (in 2001-2002 and 2005).

According to the Polio Eradication Initiative website, as of 6 Nov
2011 there have been cVDPV paralytic poliomyelitis associated cases
identified in Mozambique (2 cases of cVDPV type 1), Nigeria (13 cases
of cVDPV type 2), Yemen (4 cases of cVDPV type 2), Somalia (5 cases of
cVDPV type 2), and Afghanistan (1 case of cVDPV type 2). (See
http://www.polioeradication.org/Dat...week/Circulatingvaccinederivedpoliovirus.aspx).

For a map of Madagascar showing provinces, see
http://www.madbookings.com/madagascar/maps/madagascar_political_map.jpg.
For the interactive HealthMap/ProMED-mail map of Toliara province, see
http://healthmap.org/r/1lUh. For a map of the location of the 2005
cVDPV cases in Madagascar, see
http://jid.oxfordjournals.org/content/197/10/1427/F1.large.jpg. -
Mod.MPP]
 
Back
Top Bottom