We thank the editors of ProMED for assisting in bringing visibility to reports of AFP in Haiti. Below we provide a public response to PAHO's official announcement in ProMED of their investigation in Haiti.
In reporting the event, we were aware of the low case fatality rate associated with wild type polio, however we offer the following counterpoints to consider:
1. the denominator associated with any infectious disease in Haiti is elusive due to poor public health (including diagnostic laboratory capacity) and medical infrastructure- and despite international attention to cholera- therefore reporting bias remains on the side of severe illness and fatalities;
2. the 2000-2001 outbreak of VDPV Type 1 was associated with 2 fatalities and involved cases in Port de Paix;
3. and we offer the current polio outbreak ongoing in the Republic of Congo, reported in the 24 December 2010 (vol 330) copy of Science titled "Polio Outbreak Breaks the Rules", where we find the article's observation a relevant commentary on surveillance bias:
"Polio usually strikes children under age 5, paralyzing one in 200 of those infected and killing at most 5%, occasionally up to 10% in developing countries. The new outbreak tearing through this West African country has so far killed an estimated 42% of its victims, who, in another unusual twist, are mostly males between the ages of 15 and 25. Since it began in early October, the outbreak has paralyzed more than 476 people and killed at least 179, according to World Health Organization (WHO) estimates from early December, making this one of the largest and deadliest polio outbreaks in recent history. And one of the most mystifying, too, says polio expert Neal Nathanson of the University of Pennsylvania: 'There are too many things that don’t fit or are unexpected.'" [see attached]
We also would like to provide several points of clarification to the PAHO report:
1. First notification by HEAS to PAHO and CDC was time-stamped and dated 9 January 2011 at 1958 EST, with acknowledgement by PAHO received on 10 January 2011 at 0735 EST
2. Samples have been reportedly difficult to obtain because the bodies were unavailable due to burial
3. An additional 6 cases (9 total) beyond the apparent cluster in Port de Paix have been identified, described as "ascending paralysis", a total of 4 had died
4. We propose an inability under these circumstances to obtain positive samples may not represent a negative finding but rather, an inconclusive finding
5. Regarding the discussion of ODS, we are aware, anecdotally, of debate among clinicians in the beginning of the cholera epidemic regarding the use of normal saline-based IV fluid resuscitation versus lactate ringers- improper electrolyte management is certainly a worthy consideration
Field experience in Haiti has shown us prior assumptions of epidemiological baseline and infectious disease behavior have been challenged dramatically, as revealed most recently by the debate of whether the cholera disaster was due to an endemic or exotic introduction. Further, we have found reported vaccination coverage to be extremely difficult to validate, owing to lack of a patient identification system, vaccination records, and the challenge of reaching remote mountainous areas containing populations that have not been censused or even provided a geographic coordinate. We have found the northwest in particular to be an area of Haiti associated with reporting delays and associated difficulties with situational awareness due to limited infrastructure.
We applaud PAHO's proposed conservative intervention, "As a prudent measure, polio vaccine has been added to an upcoming vaccination campaign against diphtheria and measles in the Nord-Ouest Department", but remain perplexed why the 2000-2001 outbreak of Vaccine-Derived PolioVirus Type 1 was not acknowledged in the historical review of poliovirus activity in Hispaniola. Peer-reviewed, published findings at the time provided evidence of not only transmission of a reverted, recombined poliovirus that was lethal but was associated with biological properties indistinguishable from wild type. Subsequent studies by Vinje et al revealed presence of VDPV Type I in stream and sewage waters.
We invite commentary regarding the potential of VDPV Type 1 persistence in Haiti's environment, especially given the difficulties in ensuring vaccination coverage. We also invite commentary regarding the continued use of OPV versus IPV in that country.
James M. Wilson V, MD
Haiti Epidemic Advisory System (HEAS)
Executive Director
Praecipio International
Washington-Houston-Port au Prince
jim.wilson@praecipiointernational.org
+1.571.225.3671
Praecipio International is a charitable non-profit organization devoted to the promotion of operational biosurveillance worldwide.
On Jan 27, 2011, at 8:41 AM, ProMED-mail wrote:
ACUTE FLACCID PARALYSIS - HAITI (03): OSMOTIC DEMYELINATION SYNDROME,
PAHO
********************************************************
A ProMED-mail post
<http://www.promedmail.org>
ProMED-mail is a program of the
International Society for Infectious Diseases
<http://www.isid.org>
In this update:
[1] PAHO/WHO news release
[2] Comment
******
[1] PAHO/WHO news release
Date: Wed 26 Jan 2011
Source: Pan American Health Organization (PAHO) press release
[edited]
<http://new.paho.org/hq/index.php?option=com_content&task=view&id=4646&Itemid=1926>
PAHO/WHO investigating paralysis cases in Port-de-Paix, Haiti
-------------------------------------------------------------
Officials from the Pan American Health Organization/World Health
Organization (PAHO/WHO), along with colleagues from Haiti's Ministry
of Health and the US Centers for Disease Control and Prevention (CDC),
are looking into 4 cases of paralysis in recovering cholera patients
in Port-de-Paix, Haiti and, pending laboratory results, are likely to
rule out polio as a cause.
Experts including toxicologists are investigating possible
contamination at a hospital or at home from medication, food or
another source as the cause of death in these cases. PAHO and CDC
officials are conducting field studies and will report their findings
as soon as laboratory results are available.
Polio was one of the 1st possibilities looked into because of the
public health implications. However, the clinical characteristics and
epidemiology of these cases make poliomyelitis a remote possibility;
in simple terms, polio does not produce a high mortality rate.
Although considered highly unlikely, polio has not been completely
ruled out, pending laboratory results of samples.
PAHO/WHO has suggested that health officials remain vigilant for
further cases and has supported local health authorities in the
investigation with technical staff including epidemiologists, a
clinician and an immunization nurse to continue the investigations. A
nurse who works with PAHO/WHO's immunization program returned from
visiting the affected communities Monday [24 Jan 2011] with samples
from some of the families. A PAHO/WHO clinician and a PAHO/WHO
immunization advisor are participating in the investigation.
PAHO/WHO field epidemiologists and local health authorities from the
Department of Nord-Ouest first reported a cluster of acute
neurological syndromes in that department [10 Jan 2011]. As of [24 Jan
2011], 4 cases with acute neurological syndrome, including 3 deaths,
were reported, with dates of onset from November to December 2010 in
the La Pointe area, Commune Port-de-Paix, and the neighboring commune
of Saint Louis du Nord. All of the cases were seen at the same cholera
treatment center and returned 2-4 days later with neurological
symptoms, at which point they were hospitalized.
Working with the Director of the Department of Nord-Ouest and local
officials, interviews with medical staff and relatives showed that the
patients were admitted to the hospital between early November and the
end of December [2010]. These patients, hospitalized for severe
cholera, presented an ascending bilateral flaccid paralysis of acute
onset 24 to 72 hours after the end of the cholera treatment. No
additional cases were detected after the initial field investigation
in the Nord-Ouest Department. Samples of blood, feces, and CSF were
taken from one patient, and laboratory results are still pending.
PAHO/WHO field epidemiologists and local health authorities notified
the central Alerts and Response Unit of these cases [10 Jan 2011].
Of the suspected cases, only 4 had symptoms and signs compatible with
paralysis. 3 have died, and one is hospitalized in Port-au-Prince. He
is recovering slowly. As a prudent measure, polio vaccine has been
added to an upcoming vaccination campaign against diphtheria and
measles in the Nord-Ouest Department.
Polio was eradicated from the Americas in 1994, 3 years after the
last case was reported in Junin, Peru. A global polio eradication
initiative was launched in 1988 and has reduced the incidence of polio
worldwide by more than 99 percent. When it was launched in 1988, more
than 350 000 children were paralyzed in more than 125 endemic
countries. In 2009, 1595 children were paralyzed in 24 countries.
Today, only 4 countries remain endemic: Afghanistan, India, Nigeria,
and Pakistan and in those countries with endemic poliovirus
transmission, cases of poliomyelitis had declined by 85 percent in
2010 compared to the same period in 2009.
--
Communicated by:
Daniel B Epstein (WDC)
Information Officer
Pan American Health Organization/World Health Organization
<epsteind@paho.org>
******
[2]
Date: Wed 26 Jan 2011
From: Niklas Danielsson <Niklas.Danielsson@ecdc.europa.eu> [edited]
Re: ProMED-mail Acute flaccid paralysis - Haiti (02): ?post cholera,
RFI 20110125.0307]
----------------------------------------------------------------------
Having read the description by Dr James Wilson on ProMED-mail [22 Jan
2011] of a group of cholera patients in Haiti who developed acute
flaccid paralysis during the recovery phase after receiving treatment
for severe dehydration/hypovolemic shock, I would propose a possible
differential diagnosis. The symptoms he describes fit a rare but well
described condition called osmotic demyelination syndrome (ODS). The
syndrome has high mortality and is associated with intravenous
correction of hyponatremia. Cholera itself, as well as oral and IV
rehydration treatment for cholera, can result in hyponatremia. A
typical feature of ODS is the biphasic presentation. Patients
initially respond well to the treatment for dehydration and
hyponatremia but later deteriorate rapidly. The patients described by
Dr Wilson first recovered, but then deteriorated within 72 hours.
Classical symptoms include symmetrical quadriplegia, dysarthria,
dysphagia, confusion, and pseudobulbar palsy. Hyponatremia seems to be
the common denominator for ODS which is also linked to chronic
alcoholism, liver disease, malnutrition, psychogenic polydipsia, and
post-surgery.
--
Niklas Danielsson
Senior expert communicable diseases
Scientific communication section
Country Cooperation and Communication Unit (CCU), ECDC
<Niklas.Danielsson@ecdc.europa.eu>
[[The news release from PAHO above mentions 4 identified cases with
an acute neurologic syndrome within 24 to 72 hours following treatment
for cholera in the Nord-Ouest Department of Haiti. In the prior
ProMED-mail report on this event there was mention of a possible 7
cases (see Acute flaccid paralysis - Haiti (02): ?post cholera, RFI
20110125.0307) under investigation. In the early stages of
identification of an outbreak, it is not uncommon to hear differing
case counts from different sources often reflecting different
reporting sources of information and often different case definitions.
At this point in time, pending results of the thorough investigations
underway, one cannot rule in or out a possible infectious etiology or
toxic exposure.
The mention of the osmotic demyelination syndrome [ODS] by Dr
Danielsson (see [2] above) is very interesting. A literature search
revealed the 1st discussion of a post hyponatremia treatment
associated demyelination by Kleinschmidt-DeMasters BK, Norenberg MD in
Science in 1981 (ref 1). The 1st published article referring to this
syndrome specifically referred to as osmotic demyelination syndrome
was by Sterns, Riggs, and Schochet in the NEJM in 1986 (ref 4).
Reviewing the references available, most of the publications refer to
single occurrences or small groups of patients identified, supporting
Dr Danielsson's mention that this is a rare syndrome and is associated
with a rapid increase in sodium following a severe hyponatremia. The
clinical description of the presentation of ODS (well summarized by Dr
Danielsson) is compatible with the presentation of the cases in Haiti
reported by Dr Wilson in the 2 prior ProMED-mail reports. It is
curious that it has not been described in the literature in
association with cholera outbreaks elsewhere in the world.
We await further information on the results of the pending laboratory
studies and further epidemiologic investigations.
ProMED-mail would also like to thank Viki Hansen-Landis and
ProMED-mail Rapporteur Mary Marshall for submitting the same PAHO/WHO
news release.
For the interactive HealthMap/ProMED map of Haiti, see
<http://healthmap.org/r/00Yn>.
References
----------
1. Kleinschmidt-DeMasters BK, Norenberg MD: Rapid correction of
hyponatremia causes demyelination: relation to central pontine
myelinolysis. Science. 1981 Mar 6; 211(4486): 1068-70 [abstract
available at <http://www.ncbi.nlm.nih.gov/pubmed/7466381>].
2. Laureno R: Central pontine myelinolysis following rapid correction
of hyponatremia. Ann Neurol. 1983 Mar; 13(3): 232-42 [abstract
available at <http://www.ncbi.nlm.nih.gov/pubmed/6847135>].
3. Norenberg MD, Leslie KO, Robertson AS: Association between rise in
serum sodium and central pontine myelinolysis. Ann Neurol. 1982 Feb;
11(2): 128-35 [abstract available at
<http://www.ncbi.nlm.nih.gov/pubmed/7073246>].
4. Sterns RH, Riggs JE, Schochet SS Jr: Osmotic demyelination
syndrome following correction of hyponatremia. N Engl J Med. 1986 Jun
12; 314(24): 1535-42 [abstract available at
<http://www.nejm.org/doi/full/10.1056/NEJM198606123142402>].
5. King JD, Rosner MH: Osmotic demyelination syndrome. Am J Med Sci.
2010 Jun; 339(6): 561-7 [abstract available at
<http://www.ncbi.nlm.nih.gov/pubmed/20453633>]. - Mod.MPP]]
[see also:
Acute flaccid paralysis - Haiti (02): ?post cholera, RFI
20110125.0307
Acute flaccid paralysis - Haiti: RFI 20110121.0256
.................................................mpp/mj/jw
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