Circulation and Molecular Epidemiology of Enteroviruses in Paralyzed, Immunodeficient and Healthy Individuals in Tunisia, a Country with a Polio-Free Status for Decades

This report is an overview of enterovirus (EV) detection in Tunisian polio-suspected paralytic cases (acute flaccid paralysis (AFP) cases), healthy contacts and patients with primary immunodeficiencies (PID) during an 11-year period. A total of 2735 clinical samples were analyzed for EV isolation and type identification, according to the recommended protocols of the World Health Organization. Three poliovirus (PV) serotypes and 28 different nonpolio enteroviruses (NPEVs) were detected. The NPEV detection rate was 4.3%, 2.8% and 12.4% in AFP cases, healthy contacts and PID patients, respectively. The predominant species was EV-B, and the circulation of viruses from species EV-A was noted since 2011. All PVs detected were of Sabin origin. The PV detection rate was higher in PID patients compared to AFP cases and contacts (6.8%, 1.5% and 1.3% respectively). PV2 was not detected since 2015. Using nucleotide sequencing of the entire VP1 region, 61 strains were characterized as Sabin-like. Among them, six strains of types 1 and 3 PV were identified as pre-vaccine-derived polioviruses (VDPVs). Five type 2 PV, four strains belonging to type 1 PV and two strains belonging to type 3 PV, were classified as iVDPVs. The data presented provide a comprehensive picture of EVs circulating in Tunisia over an 11-year period, reveal changes in their epidemiology as compared to previous studies and highlight the need to set up a warning system to avoid unnoticed PVs.

Molecular detection of cosaviruses in a patient with acute flaccid paralysis and in sewage samples in Germany

Cosaviruses (CoSV) were first identified in stool samples collected from non-polio acute flaccid paralysis (AFP) cases and their healthy contacts in Pakistan in 2003. The clinical importance of CoSV remains unclear as data on epidemiology are scarce and no routine diagnostic testing is done. In this study, we characterized human CoSV (HCoSV) in a child with non-polio AFP and in sewage samples collected in Berlin, Germany. Using unbiased high-throughput sequencing and specific PCR, we characterized a HCoSV-D in stool samples of a three-year-old child hospitalized in Germany with non-polio AFP and travel history to Pakistan. The shedding pattern and absence of other relevant pathogens suggests that HCoSV-D may have been involved in the genesis of AFP. The HCoSV-RNA concentration was high, with 2.57 × 10⁶ copies per mL fecal/suspension, decreasing in follow-up samples. To investigate the possibility of local circulation of HCoSV, we screened Berlin sewage samples collected between 2013 and 2018. Molecular testing of sewage samples has shown the presence of CoSV in several parts of the world, but until now not in Germany. Of our sewage samples, 54.3 % were positive for CoSV, with up to three viral species identified in samples. Phylogenetically, the German sequences clustered intermixed with sequences obtained globally. Together, these findings emphasize the need for further clinical, epidemiological, environmental, pathogenicity and phylogenetic studies of HCoSV.

Molecular typing and characterization of a novel genotype of EV-B93 isolated from Tibet, China

EV-B93 is a novel serotype within the Enterovirus B species and is uncommon worldwide. Currently, only one full-length genomic sequence (the prototype strain) has been deposited in the GenBank database. In this study, three EV-B93 were identified, including one from an acute flaccid paralysis (AFP) patient (named 99052/XZ/CHN/1999, hereafter XZ99052) and two from healthy children (named 99096/XZ/CHN/1999 and 99167/XZ/CHN/1999, hereafter XZ99096 and XZ99167, respectively) from Tibet in 1999 during the polio eradication program. The identity between the nucleotide and amino acid sequences of the Tibet EV-B93 strain and the EV-B93 prototype strain is 83.2%–83.4% and 96.8%–96.9%, respectively. The Tibet EV-B93 strain was found to have greater nucleotide sequence identity in the P3 region to another enterovirus EV-B107 as per a phylogenetic tree analysis, which revealed that recombination occurred. Seroepidemiology data showed that EV-B93 has not produced an epidemic in Tibet and there may be susceptible individuals. The three Tibet EV-B93 strains are temperature-resistant with prognosticative virulence, suggesting the possibility of a potential large-scale outbreak of EV-B93. The analyzed EV-B93 strains enrich our knowledge about this serotype and provide valuable information on global EV-B93 molecular epidemiology. What is more, they permit the appraisal of the serotype's potential public health impact and aid in understanding the role of recombination events in the evolution of enteroviruses.

United Kingdom Acute Flaccid Paralysis (AFP) Task Force. An increase in reports of acute flaccid paralysis (AFP) in the United Kingdom, 1 January 2018-21 January 2019: early findings

During 2018, the United Kingdom experienced an increase in reports of cases of acute flaccid paralysis (AFP). As at 21 January 2019, 40 cases had been identified with a peak in October 2018. The increase was temporally associated with an upsurge in enterovirus (EV) D68 activity. Enterovirus was detected in 15 cases, mainly from respiratory tract samples; nine were typed as EV-D68. A national task force has been established and investigations are ongoing.

Clinical Features of Acute Flaccid Myelitis Temporally Associated With an Enterovirus D68 Outbreak: Results of a Nationwide Survey of Acute Flaccid Paralysis in Japan, August-December 2015

Background

Acute flaccid myelitis (AFM) is an acute flaccid paralysis syndrome with spinal motor neuron involvement of unknown etiology. We investigated the characteristics and prognostic factors of AFM clusters coincident with an enterovirus D68 (EV-D68) outbreak in Japan during autumn 2015.

Methods

An AFM case series study was conducted following a nationwide survey from August to December 2015. Radiographic and neurophysiologic data were subjected to centralized review, and virology studies were conducted for available specimens.

Results

Fifty-nine AFM cases (58 definite, 1 probable) were identified, including 55 children and 4 adults (median age, 4.4 years). The AFM epidemic curve showed strong temporal correlation with EV-D68 detection from pathogen surveillance, but not with other pathogens. EV-D68 was detected in 9 patients: 5 in nasopharyngeal, 2 in stool, 1 in cerebrospinal fluid (adult case), and 1 in tracheal aspiration, nasopharyngeal, and serum samples (a pediatric case with preceding steroid usage). Cases exhibited heterogeneous paralysis patterns from 1- to 4-limb involvement, but all definite cases had longitudinal spinal gray matter lesions on magnetic resonance imaging (median, 20 spinal segments). Cerebrospinal fluid pleocytosis was observed in 50 of 59 cases (85%), and 8 of 29 (28%) were positive for antiganglioside antibodies, as frequently observed in Guillain-Barré syndrome. Fifty-two patients showed variable residual weakness at follow-up. Good prognostic factors included a pretreatment manual muscle strength test unit score >3, normal F-wave persistence, and EV-D68-negative status.

Conclusions

EV-D68 may be one of the causative agents for AFM, while host susceptibility factors such as immune response could contribute to AFM development.

Causation of Acute Flaccid Paralysis by Myelitis and Myositis in Enterovirus-D68 Infected Mice Deficient in Interferon αβ/γ Receptor Deficient Mice

Enterovirus D68 (EV-D68) caused a large outbreak in the summer and fall of 2014 in the United States. It causes serious respiratory disease, but causation of associated paralysis is controversial, because the virus is not routinely identified in cerebrospinal fluid. To establish clinical correlates with human disease, we evaluated EV-D68 infection in non-lethal paralysis mouse models. Ten-day-old mice lacking interferon responses were injected intraperitoneally with the virus. Paralysis developed in hindlimbs. After six weeks of paralysis, the motor neurons were depleted due to viral infection. Hindlimb muscles were also infected and degenerating. Even at the earliest stage of paralysis, muscles were still infected and were degenerating, in addition to presence of virus in the spinal cord. To model natural respiratory infection, five-day-old mice were infected intranasally with EV-D68. Two of the four infected mice developed forelimb paralysis. The affected limbs had muscle disease, but no spinal cord infection was detected. The unique contributions of this study are that EV-D68 causes paralysis in mice, and that causation by muscle disease, with or without spinal cord disease, may help to resolve the controversy that the virus can cause paralysis, even if it cannot be identified in cerebrospinal fluid.

[Acute flaccid myelitis amongst Swedish children with a possible link to an outbreak of enterovirus D68]

Acute flaccid myelitis amongst Swedish children with a possible link to an outbreak of enterovirus D68 In september 2016 we had several cases of acute flaccid myelitis in our clinic. This coincided with an outbreak of enterovirus D68 (EV-D68) in Sweden during the same period. We describe three cases, of which one tested positive for EV-D68. Acute flaccid paralysis of one or more limbs preceded by an upper respiratory tract infection is highly suspicious of myelitis, and a viral cause must be included in the clinical work-up. In order to detect infection with EV-D68 in suspected acute flaccid myelitis, nasopharyngeal aspirate should be performed as early as possible. EV-D68 is normally not found in stool or cerebrospinal fluid tests but should be included in the clinical work-up. Treatment of acute flaccid myelitis is supportive only. There is no effective antiviral treatment and immunomodulating therapies show little effect. Persisting neurological deficits are common but lethal cases are rare.

Preponderance of enterovirus C in RD-L20B-cell-culture-negative stool samples from children diagnosed with acute flaccid paralysis in Nigeria

Recently, a reverse transcriptase semi-nested polymerase chain reaction (RT-snPCR) assay was recommended by the WHO for direct detection of enteroviruses in clinical specimens. In this study, we use this assay and a modification thereof to screen acute flaccid paralysis (AFP) samples that had previously tested negative for enteroviruses by the RD-L20B algorithm. Thirty paired stool suspensions collected in 2015 as part of the national AFP surveillance program in different states of Nigeria were analyzed in this study. The samples had previously tested negative for enteroviruses in the polio laboratory in accordance with the WHO-recommended RD-L20B-cell-culture-based algorithm. Two samples that had previously been found to contain enteroviruses were included as positive controls. All samples were subjected to RNA extraction, the RT-snPCR assay and a modified version of the RT-snPCR. All amplicons were sequenced, and enteroviruses were identified using the enterovirus genotyping tool and phylogenetic analysis. Amplicons were recovered from the two controls and 50% (15/30) of the samples screened. Fourteen were successfully typed, of which, 7.1% (1/14), 21.4% (3/14), 64.3% (9/14) and 7.1% (1/14) were enterovirus (EV) -A, EV-B, EV-C and a mixture of EV-B and C (EV-C99 and E25), respectively. The two controls were identified as EV-C99 and coxsackievirus (CV) -A1, both of which belong to the species Enterovirus C. In one sample, poliovirus serotype 2 was detected and found to have the VP1 _ILE143 variation and was therefore identified as a vaccine strain. The results of this study showed that significant proportion of enterovirus infections (including some with Sabin PV2) are being missed by the RD-L20B-cell-culture-based algorithm, thus highlighting the value of the RT-snPCR assay and its modifications. The circulation and preponderance of EV-C in Nigeria was also confirmed.

A mouse model of paralytic myelitis caused by enterovirus D68

In 2014, the United States experienced an epidemic of acute flaccid myelitis (AFM) cases in children coincident with a nationwide outbreak of enterovirus D68 (EV-D68) respiratory disease. Up to half of the 2014 AFM patients had EV-D68 RNA detected by RT-PCR in their respiratory secretions, although EV-D68 was only detected in cerebrospinal fluid (CSF) from one 2014 AFM patient. Given previously described molecular and epidemiologic associations between EV-D68 and AFM, we sought to develop an animal model by screening seven EV-D68 strains for the ability to induce neurological disease in neonatal mice. We found that four EV-D68 strains from the 2014 outbreak (out of five tested) produced a paralytic disease in mice resembling human AFM. The remaining 2014 strain, as well as 1962 prototype EV-D68 strains Fermon and Rhyne, did not produce, or rarely produced, paralysis in mice. In-depth examination of the paralysis caused by a representative 2014 strain, MO/14-18947, revealed infectious virus, virion particles, and viral genome in the spinal cords of paralyzed mice. Paralysis was elicited in mice following intramuscular, intracerebral, intraperitoneal, and intranasal infection, in descending frequency, and was associated with infection and loss of motor neurons in the anterior horns of spinal cord segments corresponding to paralyzed limbs. Virus isolated from spinal cords of infected mice transmitted disease when injected into naïve mice, fulfilling Koch’s postulates in this model. Finally, we found that EV-D68 immune sera, but not normal mouse sera, protected mice from development of paralysis and death when administered prior to viral challenge. These studies establish an experimental model to study EV-D68-induced myelitis and to better understand disease pathogenesis and develop potential therapies.

Reports of polio-like paralysis, referred to as acute flaccid myelitis (AFM), have recently emerged in association with infections caused by enterovirus D68 (EV-D68). In the second half of 2014, 120 cases of AFM, mostly in young children, were reported during a nationwide outbreak of EV-D68 respiratory disease. The number of AFM cases has risen again in 2016. Although epidemiological evidence between EV-D68 infection and AFM is accumulating, a causal link has not been definitely established. Here we demonstrate that strains of EV-D68 recovered during the 2014 epidemic can cause a paralytic illness in mice that resembles human AFM. Evidence that EV-D68 causes paralysis in this mouse model include: (1) loss of spinal cord motor neurons innervating paralyzed limbs, (2) detection of virus in the spinal cord and, specifically, motor neurons, (3) transmission of neurological disease when injecting virus isolated from spinal cords of paralyzed mice into naïve mice, thus fulfilling Koch’s postulates, and (4) the ability to prevent AFM by pre-administering serum containing EV-D68 antibodies from previously infected mice. This experimental mouse model can be used to better understand the pathogenesis of EV-D68-induced CNS disease and to facilitate the development of potential therapies.

Dogs that develop rabies post-vaccination usually manifest the paralytic subtype

Rabies infection can manifest as either encephalitic (furious) or paralytic (dumb) types, with a ratio of approximately 2:1 in dogs. The clinical type of rabies that develops post-vaccination has only been reported in studies from one country, all with similar findings. We report a study of 36 rabid dogs with obtainable vaccination history, presenting to The Queen Saovabha Memorial Institute, Bangkok, Thailand during 2002-2008. Dogs were classified into encephalitic or paralytic types. Of 22 non-vaccinated dogs, 16 (73%) had the encephalitic type. In contrast, of the 14 vaccinated dogs, 10 (71%) had the paralytic type, a difference that was significant (p=0.016). Recent studies on canine brains have shown that lymphocyte response is more pronounced in paralytic rabies at the brainstem level, whereas viral burden is greater in the encephalitic form. We postulate partial immune response in the vaccinated dogs might influence rabies to manifest as the paralytic type. These results can serve as a natural experiment that can help explain the basis for the differences between the paralytic and encephalitic forms of canine rabies.

Acute Flaccid Paralysis Associated with Novel Enterovirus C105

An outbreak of acute flaccid paralysis among children in the United States during summer 2014 was tentatively associated with enterovirus D68 infection. This syndrome in a child in fall 2014 was associated with enterovirus C105 infection. The presence of this virus strain in North America may pose a diagnostic challenge.

[Genetic Characteristics of Coxsackievirus Group A Type 4 Isolated from Patients with Acute Flaccid Paralysis in Shaanxi, China]

We analyzed the genetic characteristics of coxsackievirus A4 (CV-A4) based on the entire VP1 coding region. Samples were isolated from patients with acute flaccid paralysis (AFP) in Shaanxi, China from 2006 to 2010. We wished to ascertain the predominant genotype and the relationship between CV-A4 infection and AFP. Sixty-eight non-polio enteroviruses were inoculated onto RD cells (to increase the virus titer) and molecular typing was undertaken. The entire VP1 coding region was amplified. Percentage of CV-A4 was 10.3% (7/68). Analyses of genetic identify and creation of phylogenetic trees revealed that CV-A4 could be classified into A, B and C genotypes. Seven CV-A4 strains from Shaanxi and other CV-A4 strains from China formed an independent evolution lineage located in group 4 and belonged to the C2 sub-genotype. These data suggested that CV-A4 strains of sub-genotype C2 were the predominant genotypes in China. These strains co-evolved and co-circulated with those from other provinces in China, so continued monitoring of CV-A4 (by clinical and genetic surveillance) should be enhanced.

Genetic diversity of enterovirus A71, India

We have identified circulation of 3 genogroups of enterovirus (EV) A71 in India. A new genogroup (proposed designation G) was discovered during this study. We isolated genogroups D and G in wide geographic areas but detected subgenogroup C1 only in 1 focus in western India. A systematic nationwide search for EV-A71 is warranted.

Dysgeusia in a Patient with Guillain-Barré Syndrome Associated with Acute Hepatitis E: A Case Report and Literature Review

Guillain-Barré syndrome (GBS) is usually triggered by viral or bacterial infection. In addition, it was recently reported that infection with hepatitis E virus (HEV) also causes GBS. A 49-year-old man presented with acute-onset paralysis in all extremities and dysgeusia during an episode of acute hepatitis. Serological tests showed the presence of anti-HEV IgM antibodies and HEV-RNA in the serum. As an electrophysiological examination showed acute demyelinating polyradiculoneuropathy, the patient was diagnosed as HEV-associated GBS. Following the initiation of treatment with intravenous immunoglobulin, his paralysis and dysgeusia rapidly improved. This case suggests that HEV-associated GBS may rarely be complicated by dysgeusia.

RAPID COMMUNICATION-- POLIO VACCINE COVERAGE IN THE ACUTE FLACCID PARALYSIS (AFP) CASES IN ROMANIA

Poliovirus (PV), a member of the Enterovirus genus, is the etiological agent of poliomyelitis. A study carried out between 2013-2014 on 30 serum samples from acute flaccid paralysis (AFP) cases, showed a protective antibody level of 90% against poliovirus Sabin strains type 1 and type 2 and of 88% against type 3. No PV strains were isolated from 2009 to 2015 in Romania. Maintaining a high vaccine coverage level against polio is mandatory until global polio eradication, especially as the risk of polio importation remains elevated in Romania.

National Committee for the Certification of Wild Poliovirus Eradication in Hong Kong. Fifteen years of acute flaccid paralysis surveillance in Hong Kong: findings from 1997 to 2011

AIM

Acute flaccid paralysis (AFP) surveillance system was set up in Hong Kong in 1997 for World Health Organization's (WHO) certification of poliomyelitis eradication. This paper describes and reviews the demographic, clinical and virological characteristics of AFP cases reported to the system in its first 15 years.

METHODS

All patients aged under 15 years presented with acute onset of paralysis of any limbs reported to the Department of Health from January 1997 to December 2011 were reviewed. Data on demographic characteristics, vaccination history, clinical presentation and virological investigation on stool specimens collected during investigation were analysed with descriptive statistics.

RESULTS

Of the 247 cases reported, about 45% were aged under five. All cases were classified as non-polio AFP according to WHO classification. About 60% were identified with neurological disorders, with Guillain-Barré syndrome (25.9%) and myelitis (13.4%) being the most common. Viruses were detected in 14.0% of the AFP cases, with non-polio enteroviruses (NPEV) (60.0%) and adenoviruses (31.4%) accounted for most of the positive detections. Most performance indicators set by the WHO were fulfilled.

CONCLUSIONS

The AFP surveillance facilitated the clinical, virological and epidemiological examination of paediatric AFP cases. From 1997 to 2011, Guillain-Barré syndrome and myelitis were the most common among paediatric AFP cases in Hong Kong. NPEV and adenoviruses accounted for most of the positive viral detections. No wild poliovirus was detected, and all cases were classified as non-polio AFP.

Emergence of vaccine-derived polioviruses, Democratic Republic of Congo, 2004-2011

Polioviruses isolated from 70 acute flaccid paralysis patients from the Democratic Republic of Congo (DRC) during 2004-2011 were characterized and found to be vaccine-derived type 2 polioviruses (VDPV2s). Partial genomic sequencing of the isolates revealed nucleotide sequence divergence of up to 3.5% in the viral protein 1 capsid region of the viral genome relative to the Sabin vaccine strain. Genetic analysis identified at least 7 circulating lineages localized to specific geographic regions. Multiple independent events of VDPV2 emergence occurred throughout DRC during this 7-year period. During 2010-2011, VDPV2 circulation in eastern DRC occurred in an area distinct from that of wild poliovirus circulation, whereas VDPV2 circulation in the southwestern part of DRC (in Kasai Occidental) occurred within the larger region of wild poliovirus circulation.

[Serotype distribution of non-polio enterovirus in patients with acute flaccid paralysis during 2011-2012 in Hebei Province, China]

This study aims to investigate the serotype distribution of non-polio enterovirus (NPEV) isolated from patients with acute flaccid paralysis (AFP) during 2011-2012 in Hebei Province, China and to analyze the relationship between these viruses and AFP. NPEV strains were isolated from the stool specimens from AFP cases in Hebei using human rhabdomyosarcoma cells (RD) and the mouse cell line expressing the gene for the human cellular receptor for poliovirus (L20B) according to the WHO requirements. The nucleotide sequence of VP1 region was determined, and the serotypes of NPEV were identified by molecular typing. The results showed that among the 82 strains of NPEV isolated from the AFP cases during 2011-2012, 42 isolates (55.3%) were identified as human enterovirus A (HEV-A), which were classified into 4 serotypes, 34 (44.7%) as human enterovirus B (HEV-B), which were classified into 13 serotypes, 2 as adenovirus, and 4 were untyped; human enteroviruses C and D were not found in these cases. Enterovirus A71 (EV-A71) was the main type of HEV-A, accounting for 85.7% of all HEV-A strains. HEV-A, especially EV-A71, was predominant among the NPEV strains isolated from AFP patients during 2011-2012 in Hebei Province.

Characterization of a novel enterovirus serotype and an enterovirus EV-B93 isolated from acute flaccid paralysis patients

Non-polio enteroviruses (NPEVs) are among the most common viruses infecting humans worldwide. Most of these infections are asymptomatic but few can lead to systemic and neurological disorders like Acute Flaccid Paralysis (AFP). Acute Flaccid Paralysis is a clinical syndrome and NPEVs have been isolated frequently from the patients suffering from AFP but little is known about their causal relationship. The objective of this study was to identify and characterize the NPEV serotypes recovered from 184 stool samples collected from AFP patients in Federally Administered Tribal Areas (FATA) in north-west of Pakistan. Overall, 44 (95.6 %) isolates were successfully typed through microneutralization assay as a member of enterovirus B species including echovirus (E)-2, E-3, E-4, E-6, E-7, E-11, E-13, E-14, E-21 and E-29 while two isolates (PAK NIH SP6545B and PAK NIH SP1202B) remained untypeable. The VP1 and capsid regions analysis characterized these viruses as EV-B93 and EV-B106. Phylogenetic analysis confirmed that PAK NIH isolates had high genetic diversity and represent distinct genotypes circulating in the country. Our findings highlight the role of NPEVs in AFP cases to be thoroughly investigated especially in high disease risk areas, with limited surveillance activities and health resources.

Clinical and neuroimaging features of enterovirus71 related acute flaccid paralysis in patients with hand-foot-mouth disease

OBJECTIVE

To investigate clinical and neuroimaging features of enterovirus71 (EV71) related acute flaccid paralysis in patients with hand-foot-mouth disease.

METHODS

Nine patients with acute flaccid paralysis met the criterion of EV71 induced hand-foot-mouth disease underwent spinal and brain MR imaging from May 2008 to Sep 2012.

RESULTS

One extremity flaccid was found in four cases (3 with lower limb, 1 with upper limb), two limbs flaccid in three cases (2 with lower limbs, 1 with upper limbs), and four limbs flaccid in two cases. Spinal MRI studies showed lesion with high signal in T2-weighted images (T2WI) and low signal T1-weighted images (T1WI) in the spinal cord of all nine cases, and the lesions were mainly in bilateral and unilateral anterior horn of cervical spinal cord and spinal cord below thoracic 9 (T9) level. In addition, the midbrain, pons, and medulla, which were involved in 3 cases with brainstem encephalitis, demonstrated abnormal signal. Moreover, spinal cord contrast MRI studies showed mild enhancement in corresponding anterior horn of the involved side, and strong enhancement in its ventral root.

CONCLUSIONS

EV71 related acute flaccid paralysis in patients with hand-foot-mouth disease mainly affected the anterior horn regions and ventral root of cervical spinal cord and spinal cord below T9 level. MR imaging could efficiently show the characteristic pattern and extent of the lesions which correlated well with the clinical features.

Annual report of the Australian National Enterovirus Reference Laboratory 2010-2011

Australia conducts clinical surveillance for cases of polio-like illness in children in accordance with the World Health Organization (WHO) recommended surveillance criteria for acute flaccid paralysis (AFP). AFP cases are ascertained either by clinicians notifying the Australian Paediatric Surveillance Unit or designated nurses enrolling cases as part of the Paediatric Active Enhanced Disease Surveillance system at four sentinel tertiary paediatric hospitals. The National Enterovirus Reference Laboratory (NERL), formerly the National Poliovirus Reference Laboratory, is accredited by the World Health Organization (WHO) for the testing of faecal specimens from cases of AFP and operates as a Poliovirus Regional Reference Laboratory for the Western Pacific Region. In 2010 and 2011, for the 3rd and 4th consecutive years, Australia met the WHO AFP surveillance performance indicator. This is indicative of a sensitive surveillance system capable of detecting an imported case of polio in children. However, the faecal collection rate for the virological investigation of AFP cases was below the WHO surveillance performance indicator in both years and represented a gap in Australia's polio surveillance. Enterovirus and environmental surveillance were established in Australia as virological surveillance to complement the clinical surveillance schemes. No poliovirus was detected by the clinical or virological surveillance schemes in 2010 or 2011 and Australia maintained its polio-free status. India was declared polio-free in January 2012, a significant step towards global polio eradication, leaving Afghanistan, Nigeria and Pakistan as the remaining countries endemic for wild poliovirus.

Review of Australia's polio surveillance

With eradication almost within reach, the importance of detecting every poliomyelitis case has taken on additional significance. The selected surveillance strategy must be effective and efficient. A review of polio surveillance in Australia was conducted to consider whether current strategies were optimal. Document review and semi-structured key informant interviews were used to conduct the review. Interviews were recorded, transcribed and thematically analysed. The review was an iterative process with feedback on the findings sought from interviewees. Since Western Pacific Regional polio-elimination status was certified, one imported adult case was detected in 2007 in Australia, with no evidence of further transmission, and no Australian paediatric cases identified. Respondents reported that: it was not possible to prevent importations; paediatric cases were more likely to be identified than adult cases; and there may be a low level of suspicion among clinicians. Case detection and outbreak mitigation were considered key reasons to undertake polio surveillance. While Australia has not achieved one of the key World Health Organization (WHO) surveillance targets, this did not compromise Australias polio-free status. Identified issues with polio surveillance were the potential for an importation with high attendant investigation and containment costs, low stool sample collection rates, and the opportunity to improve safeguards around the importation and laboratory storage of biological samples containing poliovirus. The review found strong support for ongoing polio surveillance, particularly to detect imported cases and to demonstrate commitment to maintaining a polio-free region. Existing polio surveillance strategies were considered appropriate for Australia.

Annual report of the Australian National Enterovirus Reference Laboratory 2012

In 2012 no cases of poliomyelitis were reported through clinical surveillance in Australia, and poliovirus was not detected through virological surveillance. Australia conducts surveillance for cases of acute flaccid paralysis (AFP) in children less than 15 years as the main mechanism to monitor its polio-free status in accordance with World Health Organization (WHO) recommendations. Cases of AFP in children are notified to the Australian Paediatric Surveillance Unit or the Paediatric Active Enhanced Disease Surveillance System. In 2012 Australia reported 1.2 non-polio AFP cases per 100,000 children, meeting the WHO performance criterion for a sensitive system for the fifth year in a row. However the faecal specimen collection rate from AFP cases was 29%, which was well below the WHO target of 80%. Virological surveillance for poliovirus consists of two components. Firstly, the Enterovirus Reference Laboratory Network of Australia (ERLNA) reports on the typing of enteroviruses detected in or isolated from clinical specimens. Secondly, environmental surveillance is conducted at sentinel sites. These surveillance systems are co-ordinated by the National Enterovirus Reference Laboratory (NERL).

[Isolation and characterization of a human enterovirus 74 isolated in Shandong Province, China]

Human Enterovirus HEV 74 is a new member of species Human enterovirus B (HEV-B). To understand its evolution and restructuring characteristics, we report the complete genome sequence of a HEV74 strain 05293/SD/CHN/2005(abbreviated as 05293) isolated from an acute flaccid paralysis (AFP) case in Shangdong Province, China, 2005. Analysis of the complete genomic sequence of 05293 showed that its genome was collinear with that of previously described 2 HEV74 strains, except for insertions and deletions at the 5'NTR and the 3 NTR regions. The complete genome sequence of strain 05293 displayed 80. 8% nucleotide and 96% amino acid identity to the prototype strain USA/CA75-10213, and 80. 6% and 95. 9% to another isolated strain Rikaze-136. The P1, P2 and P3 coding regions of strain 05293 displayed 81. 5%, 80. 0%, 79. 7% nucleotide and 95. 9%, 96. 0%, 96.2% amino acid identity to the prototype strain USA/CA75-10213, and 81. 9%, 78. 8%, 79. 5% and 95. 9%, 96. 1%, 95. 7% to strain Rikaze-136, respectively. The phylogenetic tree and Simplot analysis on 05293 and HEV-B genome sequences were performed, and the result indicated frequent recombination within HEV-B.

Eradicating poliomyelitis: India's journey from hyperendemic to polio-free status

India's success in eliminating wild polioviruses (WPVs) has been acclaimed globally. Since the last case on January 13, 2011 success has been sustained for two years. By early 2014 India could be certified free of WPV transmission, if no indigenous transmission occurs, the chances of which is considered zero. Until early 1990s India was hyperendemic for polio, with an average of 500 to 1000 children getting paralysed daily. In spite of introducing trivalent oral poliovirus vaccine (tOPV) in the Expanded Programme on Immunization (EPI) in 1979, the burden of polio did not fall below that of the pre-EPI era for a decade. One of the main reasons was the low vaccine efficacy (VE) of tOPV against WPV types 1 and 3. The VE of tOPV was highest for type 2 and WPV type 2 was eliminated in 1999 itself as the average per-capita vaccine coverage reached 6. The VE against types 1 and 3 was the lowest in Uttar Pradesh and Bihar, where the force of transmission of WPVs was maximum on account of the highest infant-population density. Transmission was finally interrupted with sustained and extraordinary efforts. During the years since 2004 annual pulse polio vaccination campaigns were conducted 10 times each year, virtually every child was tracked and vaccinated - including in all transit points and transport vehicles, monovalent OPV types 1 and 3 were licensed and applied in titrated campaigns according to WPV epidemiology and bivalent OPV (bOPV, with both types 1 and 3) was developed and judiciously deployed. Elimination of WPVs with OPV is only phase 1 of polio eradication. India is poised to progress to phase 2, with introduction of inactivated poliovirus vaccine (IPV), switch from tOPV to bOPV and final elimination of all vaccine-related and vaccine-derived polioviruses. True polio eradication demands zero incidence of poliovirus infection, wild and vaccine.

Varicella-zoster meningoencephaloradiculoneuropathy in an immunocompetent young woman

The clinical manifestations of varicella-zoster virus infections can be divided into primary infection with chickenpox and reactivated infection with dermatomal shingles, disseminated herpes zoster, zoster sine herpete and varicella-zoster virus encephalitis, meningitis and vasculopathy. We present a case of zoster sine herpete leading to meningitis with cranial and peripheral nerve palsies. A 17-year-old woman was admitted to hospital with intermittent fever, drowsiness, slowness and subsequent frontal headache and horizontal diplopia. Cerebrospinal fluid examination revealed lymphocytic pleocytosis and PCR amplified varicella-zoster virus DNA. Laboratory and clinical findings were suggestive of meningoencephaloradiculoneuropathy, stemming from varicella-zoster virus and affecting cranial and peripheral nerves. Only 5% of patients with zoster develop cranial and peripheral nerve palsies. Diagnosis is imperative in order to initiate prompt antiviral therapy so as to minimize morbidity and the risk of death.

Characterization of the non-polio enterovirus infections associated with acute flaccid paralysis in South-Western India

Non-polio enteroviruses (NPEVs) have been reported frequently in association with acute flaccid paralysis (AFP) cases during Polio Surveillance Programs (PSPs) worldwide. However, there is limited understanding on the attributes of their infections. This study reports characteristics of NPEVs isolated from AFP cases, investigated during PSPs held in 2009-2010, in Karnataka and Kerala states of south-western India having varied climatic conditions. NPEV cell culture isolates derived from stool specimens that were collected from 422 of 2186 AFP cases (<1-14 years age) and 17 of 41 asymptomatic contacts; and details of all AFP cases/contacts were obtained from National Polio Laboratory, Bangalore. The distribution of NPEV infections among AFP cases and circulation pattern of NPEV strains were determined by statistical analysis of the data. Genotyping of all NPEV isolates was carried out by partial VP1 gene sequencing and phylogenetic analysis. NPEV positive AFP cases were significantly higher in children aged <2 years; with residual paralysis; in summer months; and in regions with relatively hot climate. Genotyping of NPEVs identified predominance of human enteroviruses (HEV)-B species [81.9%-Echoviruses (E): 57.3%; coxsackieviruses (CV) B: 15%; numbered EVs: 8.9%; CVA9: 0.7%] and low levels of HEV-A [14.5%-CVA: 6%; numbered EVs: 8.5%] and HEV-C [3.6%-CVA: 2.6%; numbered EVs: 1%] species, encompassing 63 genotypes. EV76 (6.3%) and each of E3, CVB3 and E9 (4.97%) were found frequently during 2009 while E11 (6.7%), CVB1 (6.1%), E7 (5.1%) and E20 (5.1%) were detected commonly in 2010. A marked proportion of AFP cases from children aged <2 years; presenting with fever; and from north and south interior parts of Karnataka state was detected with E/numbered EVs than that found with CVA/CVB. This study highlights the extensive genetic diversity and diverse circulation patterns of NPEV strains in AFP cases from different populations and climatic conditions.

Sabin and wild type polioviruses from children who presented with acute flaccid paralysis in Nigeria

BACKGROUND

Sensitive poliovirus surveillance to detect vaccine-derived-polioviruses will continue to increase in importance.

OBJECTIVE

Isolating and identifying poliovirus strains from children of pediatrics age in Nigeria.

METHODS

A total of 120 fecal samples were randomly collected from children under the age of five who presented with acute flaccid paralysis. Samples were tested by tissue culture technique and further characterized by intratypic differentiation testing using ELISA and PCR methods.

RESULTS

The study confirmed the presence of 22(18.3%) enteroviral isolates comprising 19(86.4%) polioviruses and 3(13.6%) non-polio enteroviruses. These 19 polioviruses include: Sabin-type poliovirus-1 (15.8%), poliovirus-2 (10.5%), poliovirus-3 (10.5%) and wild-type poliovirus-1 (63.2%) isolates. It showed that poliovirus infection was higher in children ages 6-11 months (18.9%), females (18.4%), northern states (91.0%) with no vaccination record (75.0%). Wild-type poliovirus-1 was isolated from the stool samples of 12(54.6%) children from northern states and in all age groups except 18-23 months. No significant differences (P >0.05) between poliovirus infection and age (18.9% vs. 17.7%; 81.9% vs. 18.2%) and sex (18.3% vs. 18.4%). There was significant differences (P<0.05) between poliovirus infection and location (91.0% vs. 9.0%) and history of polio vaccination (75.0% vs. 0.0%). No wild-type poliovirus was found in those with complete vaccination.

CONCLUSION

This study further confirms the presence of Sabin and wild-type poliovirus among children in Nigeria. The isolation of Sabin strain of poliovirus is advantageous to the polio eradication program as it is capable of inducing natural immunity in susceptible hosts. Transmission of wild-type poliovirus among children with incomplete vaccination poses a serious threat to polio eradication program in Nigeria. Environmental and serological surveillance with larger sample size are important for monitoring poliovirus circulation in Nigeria.

The effect of mass immunisation campaigns and new oral poliovirus vaccines on the incidence of poliomyelitis in Pakistan and Afghanistan, 2001-11: a retrospective analysis

BACKGROUND

Pakistan and Afghanistan are two of the three remaining countries yet to interrupt wild-type poliovirus transmission. The increasing incidence of poliomyelitis in these countries during 2010-11 led the Executive Board of WHO in January, 2012, to declare polio eradication a "programmatic emergency for global public health". We aimed to establish why incidence is rising in these countries despite programme innovations including the introduction of new vaccines.

METHODS

We did a matched case-control analysis based on a database of 46,977 children aged 0-14 years with onset of acute flaccid paralysis between Jan 1, 2001, and Dec 31, 2011. The vaccination history of children with poliomyelitis was compared with that of children with acute flaccid paralysis due to other causes to estimate the clinical effectiveness of oral poliovirus vaccines (OPVs) in Afghanistan and Pakistan by conditional logistic regression. We estimated vaccine coverage and serotype-specific vaccine-induced population immunity in children aged 0-2 years and assessed their association with the incidence of poliomyelitis over time in seven regions of Afghanistan and Pakistan.

FINDINGS

Between Jan 1, 2001, and Dec 31, 2011, there were 883 cases of serotype 1 poliomyelitis (710 in Pakistan and 173 in Afghanistan) and 272 cases of poliomyelitis serotype 3 (216 in Pakistan and 56 in Afghanistan). The estimated clinical effectiveness of a dose of trivalent OPV against serotype 1 poliomyelitis was 12·5% (95% CI 5·6-18·8) compared with 34·5% (16·1-48·9) for monovalent OPV (p=0·007) and 23·4% (10·4-34·6) for bivalent OPV (p=0·067). Bivalent OPV was non-inferior compared with monovalent OPV (p=0·21). Vaccination coverage decreased during 2006-11 in the Federally Administered Tribal Areas (FATA), Balochistan, and Khyber Pakhtunkhwa in Pakistan and in southern Afghanistan. Although partially mitigated by the use of more effective vaccines, these decreases in coverage resulted in lower vaccine-induced population immunity to poliovirus serotype 1 in FATA and Balochistan and associated increases in the incidence of poliomyelitis.

INTERPRETATION

The effectiveness of bivalent OPV is comparable with monovalent OPV and can therefore be used in eradicating serotype 1 poliomyelitis whilst minimising the risks of serotype 3 outbreaks. However, decreases in vaccination coverage in parts of Pakistan and southern Afghanistan have severely limited the effect of this vaccine.

FUNDING

Poliovirus Research subcommittee of WHO, Royal Society, and Medical Research Council.

[Evolution and prognosis of the acute flaccid paralysis associated with enterovirus 71 infection evaluated through a clinical and magnetic resonance imaging follow-up study]

OBJECTIVE

To explore the development and prognosis of the acute flaccid paralysis (AFP) associated with enterovirus 71 (EV71) infection through clinical follow-up study for clinical and magnetic resonance imaging (MRI) features based on the research progress of virology and pathology.

METHOD

Sixteen children with HFMD associated with AFP in hospital from May 1, 2011 to August 31, 2011 were investigated and the patients received intensive rehabilitation training. The 16 cases were divided into two groups (the recovery or the sequela) by if the muscle strength recovered to level 4 after intensive rehabilitation. The MRI findings of 15 children were analyzed and among them, 6 patients were reexamined after one month. The clinical markers were compared between groups including course of disease, WBC, WBC in cerebrospinal fluid (CSF), ventilator support, therapy, the worst muscle strength, the initial tendon reflex, the muscle atrophy, and multi-limb paralysis. The data were analyzed by t test and χ2 test with SPSS10.0.

RESULT

All the 16 children were infected with enterovirus 71 (EV71). The myodynamia of 7 children were level 0, 4 children had serious upper limbs paralysis. The neck muscle in 3 cases and the brain stem motor ruckus in 4 cases were involved. The ankle clonus of non-completely paralyzed limbs in 14 cases occurred during rehabilitation. Eight children had the better prognosis, the other 8 children had sequela. 0 level muscle strength (0 case vs. 7 cases, χ2=12.4), the initial tendon reflex (2 cases vs. 8 cases, χ2=9.6), obvious muscle atrophy (0 case vs. 8 cases, χ2=16), were significantly different in the children with the recovery when compared to the sequela (P<0.01). The severe upper limbs paralysis had the worse prognosis than the severe lower limbs paralysis. MR imaging showed signs of spinal nerve root inflammation and the bilateral hyperintense lesions, symmetrical in the posterior portions of the medulla, pons, and asymmetrical in the ventral horns of cervical spinal cord. Signal enhancement occurred only in the early MRI examination.

CONCLUSION

In the evolution of AFP due to EV71 infection, the upper motor neuron damage is common, the prognosis is related with the severity of early paralysis and neuron damage. MR imaging is helpful to understand the pathological mechanism of AFP.

[Study on the prevalence of acute flaccid paralysis and hand foot mouth disease in Beijing 2006 - 2008]

OBJECTIVE

To study the prevalence of acute flaccid paralysis (AFP) and hand foot mouth disease (HFMD) in Beijing, from 2006 - 2008.

METHODS

Data on AFP and HFMD was analyzed epidemiologically, during 2006 - 2008 in Beijing. All the specimens from AFP cases were isolated and identified by RD and L20B cell and all of non-polio enterovirus (NPEV) cases were assayed by HFMD real-time PCR kit. The relationship between AFP and HFMD was analyzed.

RESULTS

During 2006 - 2008, the number of AFP case in Beijing increased from 108 to 177 while the NPEV isolation rate increased from 11.11% to 20.34% and the positive rate of enterovirus 71 (EV71) and/or coxsackie virus A16 (Cox A16) increased from 0.93% to 10.17%.

CONCLUSION

The prevalence of HFMD caused by EV71 and/or Cox A16 might have contributed to the increase of AFP cases in Beijing.

Importance of macrophage inflammatory protein-1α and splenic macrophages in neurodegeneration induced by PVC-211 murine leukemia virus

We recently reported that infection of rats with the neurodegenerative disease-causing retrovirus PVC-211 MuLV results in elevated levels of the chemokine MIP-1α followed by the accumulation of activated microglia in the brain. To investigate the importance of MIP-1α in recruitment of microglia to the brain, we treated rats with MIP-1α antibodies before and after PVC-211 MuLV infection. This caused a delay in the development of paralysis which was associated with a decrease in activated microglia without affecting virus expression. To determine the source of activated microglia, rats were splenectomized 4 days after virus infection. Splenectomized rats showed a delay in disease development that was associated with decreased numbers of activated microglia without affecting virus expression. Together, these results suggest that MIP-1α is directly involved in the neurodegeneration induced in rats by PVC-211 MuLV by recruiting macrophages/microglia from the periphery into regions of the brain that eventually become diseased.

Non-polio enteroviruses serotypes circulating in Nigeria

Enteroviruses is one of the most common group of human pathogens, causing a wide range of acute symptoms involving the cardiac and skeletal muscles, central nervous system, pancreas,skin and mucous membranes. In spite of the success recorded in polio eradication globally, infections with other enteroviruses remain frequent and sometimes very serious, requiring hospitalization. In this study we determined the various circulating serotypes of non-polio enteroviruses (NPEVs) with a view to providing information on the activity of these viruses among the Nigerian children, who usually are the most affected. Stool samples were obtained from hospitalized children at two major secondary community hospitals in Ibadan and acute flaccid paralysis (AFP) cases from 26 states ofNigeria. A presumptive identification of NPEVs was based on growth in RD cells. Isolates were identified by neutralization assay using sera obtained from the Institute for Public Health and the Environment, the Netherlands. The problems associated with this assay prompted the use of genotypic method developed at the Centers for Disease Control, Atlanta, USA for the final identification of isolates. Neutralization assay identified the 138 isolates into echoviruses (43.5%), coxsackie B viruses (29.7%) and untypeable isolates (26.8%). Finally genotyping identified echoviruses (E3, E6, E7, E11, E12, E13, E14, E19, E20, E21, E24, E29, E30, E33), coxsackieviruses (CVA3, CVA4, CVA6, CVA17, CVB3, CVB5, CVB6) and enteroviruses (EV69, EV71). The causal association of isolates with different diseases was also established. Majority of the isolates belonged to the human enterovirus gropup B (HEV-B) specie, followed by 4 and 1 in the HEV-A and HEV-C species respectively. This study forms the basis of molecular epidemiology of NPEVs being established for the first time in Nigeria. The implication of the presence of neurotropic serotypes (E3, E6, E7, E11, E14, E20, E24, E29, E30, EV71, CVB3 and CVB5) is that AFP may still be prevalent following polio eradication.

Common peroneal and tibial nerve paralysis secondary to herpes zoster infection: a case report

BACKGROUND

The usual presentation of herpes zoster (HZ) is a self-limiting vesicular rash, often accompanied by post-herpetic neuralgia. However, HZ can give rise to other complications, that have unusual presentations and serious sequelae like segmental motor paralysis of the limbs that is a relatively rare complication.

CASE

A 68-year-old man presented with foot drop on the right side had a history of HZ infection on and around the knee and the popliteal fossa. He was treated with acyclovir by a dermatologist and 10 days after the inital symptoms he developed weakness on the right ankle and on the muscles distal to the knee. In a few days foot drop has developed and he was unable to walk without help. Three months later he was admitted to the neurology out patient clinic. On his electrophysiological examination common peroneal nerve could not be stimulated on the right side. The distal latency of the tibial nerve has prolonged, CMAP amplitude has diminished and the nerve conduction velocity has slowed down. Latency of the sural nerve has prolonged with a small SNAP amplitude and a slow nerve conduction velocity on the right side. Electromyography revealed denervation on the muscles inervated by tibialis anterior and common peroneal nerves distal to the knee.

CONCLUSION

The double mononeuropathy of the tibial and common peroneal nerves secondary to HZ was not found in the published data. HZ should be considered as a possible cause of the paralysis of peripheral nerves and more attention should be paid to it.

[Identification and genetic characterization of human enterovirus type 73, 75, and 97 strains of specie B isolated in Shandong province]

Molecular typing was conducted for three human enteroviruses (HEV) isolated from acute flaccid paralysis (AFP) cases in Shandong province, China. RNAs from virus supernatants were extracted and complete VP1 genes were amplified by RT-PCR and sequenced. Genotypes of these isolates were identified as HEV type 73, 75 and 97, respectively by BLAST program. Homology and phylogenetic tree analyses were performed. Sequence analysis of VP1 gene showed significant variation compared with prototype strains. This study presents the genetic characteristics of HEV 73, 75 and 97 of specie B in Shandong Province, and the first report of HEV97 in China.

Centers for Disease Control and Prevention (CDC). Laboratory surveillance for wild and vaccine-derived polioviruses - worldwide, January 2008-June 2009

The Global Polio Laboratory Network (GPLN) isolates and characterizes polioviruses from fecal specimens of persons with acute flaccid paralysis. The network is coordinated by the World Health Organization (WHO) and includes 144 laboratories in 97 countries. Data from the network are used to guide the Global Polio Eradication Initiative by confirming polio cases, detecting and determining the origin of importations, identifying vaccine-derived polioviruses (VDPVs), and documenting the circulation of wild polioviruses (WPVs). This report updates previous reports and summarizes GPLN activities and detection of WPVs and VDPVs during January 2008-June 2009. During this period, GPLN tested 247,794 fecal samples from 127,566 acute flaccid paralysis cases, from which 14,279 (5.8%) poliovirus isolates (vaccine-related and WPV) were detected, including 4,280 (1.7%) WPVs from 22 countries. GPLN laboratory capacity and capabilities remain an integral part of surveillance for polioviruses and efforts to eliminate polio from the remaining areas of circulation.

Molecular characterization of adenoviral infections in Cuba: report of an unusual association of species D adenoviruses with different clinical syndromes

Adenoviruses are common pathogens that are responsible for a wide variety of infectious syndromes. The objectives of this study were to identify and characterize members of different adenovirus species at the molecular level and to describe the correlation between viruses and clinical syndromes during a period of 4 years. Between 2002 and 2006, 45 of 512 respiratory specimens (8%) from patients with acute respiratory tract infection tested positive for adenovirus. Four adenovirus isolates from samples sent for enterovirus isolation were also analyzed. This research identified 49 confirmed cases of human adenovirus infection by PCR and/or viral culture. The most common diagnosis was upper respiratory infection (44%). Human adenovirusD was the major species found (59%), followed by Human adenovirusC (36%) and Human adenovirusB (4%). Human adenovirus 5 was the major serotype found producing bronchiolitis, followed by human adenovirus 6. In patients with upper respiratory infection, the major serotype found was human adenovirus 17. Viruses of the species Human adenovirusD were identified in seven (77%) cases of acute febrile syndrome. Four isolates from clinical materials obtained from patients with encephalitis, acute flaccid paralysis and meningoencephalitis were identified as belonging to the species Human adenovirusD. Our data demonstrate a surprising result about the identification of an unusual association of viruses of the species Human adenovirusD with different clinical syndromes. This observation could be evaluated as a possible indicator of the emergence of a novel strain but further studies are required.

[The epidemiology character of the 503 residual paralysis of acute flaccid paralysis cases]

OBJECTIVE

Analyze the epidemiology character of the residual paralysis(RP) of acute flaccid paralysis (AFP) in Guangdong during 1994-2007.

METHODS

The viruses isolated from the excrement of RP cases were identified and typed in Guangdong from 1994 to 2007. Statistics analysis was performed to reveal the relationship among the immunization history,age,gender and the distribution of the etiology.

RESULTS

A total of 503 RP cases were reported. 150 of which were isolated with PV and 59 were isolated with NPEV. From 1994 to 2007, The PV isolating rate ranged from 18.92% to 47.06% and was higher in winter and spring, while the NPEV isolating rate ranged from 4.17% to 25.00%. and was higher in summer and autumn. The PV isolating rate decreased as the age increased,and its isolating rate (61.11%) was highest in "0" year group. The PV isolating rate of the population of < or =2 times OPV was far higher than 3 times. The PV and NPEV isolating rate of the RP cases was higher than without RP.

CONCLUSION

The case with RP caused by wild poliovirus wasn't found from 1994 to 2007 in Guangdong, but the relationship of RP case was observed between < or =2 years group and < or =1 time OPV, and NPEVs probably are the potential etiological agent that cause children RP.

West nile poliomyelitis in a 7-year-old child

West Nile poliomyelitis is a well-described neurologic manifestation of West Nile viral infection in adults. However, few reports have described this manifestation in children infected with West Nile virus. We describe a 7-year-old boy who developed West Nile poliomyelitis with flaccid paralysis of his left leg. Electrodiagnostic testing and radiologic imaging confirmed anterior horn cell injury. We report on his course clinically and electrodiagnostically over 20 months.