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Here we document the case of a domestic ferret (Mustela putorius) that survived experimental inoculation with rabies virus of skunk origin. The ferret showed initial clinical signs of rabies (hindlimb paralysis) on day 81 after inoculation. The animal survived with paraplegia but otherwise was in an adequate nutritional state until the end of the observation period (PI day 181). At necropsy, no gross lesions were observed. Microscopic lesions were found in sections of cerebrum and spinal cord. In both tissues, the lesions were similar but were more severe with loss of neuronal parenchyma in the spinal cord. The lesions consisted of locally extensive areas with proliferation of astrocytes and moderate numbers of glial cells. Severely affected areas also contained clearly defined vacuoles in the neuropil. Multifocal areas of involvement showed mononuclear cuffing of blood vessels. In a few areas, the cuffing extended to the meninges. Rabies virus antigen was not detected by immunohistochemistry of tissue sections.

The etiology of most neurodegenerative diseases of the central nervous system remains unknown and likely involves a combination of genetic susceptibility and environmental triggering factors. Given that exposure to numerous infectious pathogens occurs during childhood, and that some viral infections can lead to neurodegeneration and demyelination, it is conceivable that some viruses may act as triggering factors in neuropathogenesis. We have previously shown that the prototype OC43 strain of the common cold-associated human respiratory coronavirus has the capacity to infect human neuronal and glial cells and does persist in human brains. Moreover, it has neuroinvasive properties in susceptible BALB/c mice, where it leads to a chronic encephalitis with accompanying disabilities. Here, we show that mutations in the viral spike glycoprotein, reproducibly acquired during viral persistence in human neural cell cultures, led to a drastically modified virus-induced neuropathology in BALB/c mice, characterized by flaccid paralysis and demyelination. Even though infection by both mutated and wild-type viruses led to neuroinflammation, the modified neuropathogenesis induced by the mutated virus was associated with increased viral spread and significantly more CD4+ and CD8+ T-lymphocyte infiltration into the central nervous system, as well as significantly increased levels of the proinflammatory cytokine interleukin (IL)-6 and the chemokine CCL2 (monocyte chemoattractant protein [MCP]-1). Moreover, recombinant virus harboring the S glycoprotein mutations retained its neurotropism, productively infecting neurons. Therefore, interaction of a human respiratory coronavirus with the central nervous system may modulate virus and host factors resulting in a modified neuropathogenesis in genetically susceptible individuals.

Background: The largest recorded outbreak of a circulating vaccine-derived poliovirus (cVDPV), detected in Nigeria, provides a unique opportunity to analyze the pathogenicity of the virus, the clinical severity of the disease, and the effectiveness of control measures for cVDPVs as compared with wild-type poliovirus (WPV)., Methods: We identified cases of acute flaccid paralysis associated with fecal excretion of type 2 cVDPV, type 1 WPV, or type 3 WPV reported in Nigeria through routine surveillance from January 1, 2005, through June 30, 2009. The clinical characteristics of these cases, the clinical attack rates for each virus, and the effectiveness of oral polio vaccines in preventing paralysis from each virus were compared., Results: No significant differences were found in the clinical severity of paralysis among the 278 cases of type 2 cVDPV, the 2323 cases of type 1 WPV, and the 1059 cases of type 3 WPV. The estimated average annual clinical attack rates of type 1 WPV, type 2 cVDPV, and type 3 WPV per 100,000 susceptible children under 5 years of age were 6.8 (95% confidence interval [CI], 5.9 to 7.7), 2.7 (95% CI, 1.9 to 3.6), and 4.0 (95% CI, 3.4 to 4.7), respectively. The estimated effectiveness of trivalent oral polio vaccine against paralysis from type 2 cVDPV was 38% (95% CI, 15 to 54%) per dose, which was substantially higher than that against paralysis from type 1 WPV (13%; 95% CI, 8 to 18%), or type 3 WPV (20%; 95% CI, 12 to 26%). The more frequent use of serotype 1 and serotype 3 monovalent oral polio vaccines has resulted in improvements in vaccine-induced population immunity against these serotypes and in declines in immunity to type 2 cVDPV., Conclusions: The attack rate and severity of disease associated with the recent cVDPV identified in Nigeria are similar to those associated with WPV. International planning for the management of the risk of WPV, both before and after eradication, must include scenarios in which equally virulent and pathogenic cVDPVs could emerge., (2010 Massachusetts Medical Society)

Objective: To analyze VDPV found from acute flaccid paralysis cases and effectiveness for emergency response in Binzhou, Shandong in 2007., Methods: Outbreak investigation, rapid evaluation for oral poliomyelitis attenuate live vaccine (OPV) coverage rate, active searched for acute flaccid paralysis (AFP)cases, supervision for VDPV case, virology and serology surveillance, mopping-up of OPV were used for this emergency response to prevent the possible VDPV spread., Results: The case was reported from the AFP surveillance system. The poliovirus type I was isolated from stool specimen, which was identified as VDPV by gene sequencing. This AFP case was diagnosed as Guillain-barre syndrome (GBS) with 11 doses of OPV and normal self-immunity function test. The investigation results showed that the OPV coverage rates and the neutralization antibody to poliovirus type 1-3 were at high level among the local children, no similar VDPV was isolated from stools of healthy children around the case. The quality of AFP surveillance system was good, and had not found additional similar case in Bizhou city. Additional VDPV was not found in continuous stool specimen from this case. The case was diagnosed as VDPV infected vector but not VDPV case by the national and provincial expert group., Conclusion: This VDPV was found in the area with high coverage rate OPV, There was no evidence for the VDPV circulation. The emergency response for the VDPV was rapid and effective. The VDPV surveillance and research related should be strengthened.

Objective: In order to evaluate the running status and provide the laboratory data for maintaining polio-free status in China, the virology surveillance database of Chinese Polio Laboratories Network (not include Hong Kong, Macao, and Taiwan)in 2008 were analyzed., Methods: The case investigation data of Acute Flaccid Paralysis(AFP)cases reported by 31 provinces (municipal, autonomous regions) through EPI surveillance information management system and the database of National Polio Laboratory (NPL) were analyzed, and the indicators of running status of Chinese Polio Laboratories Network were evaluated., Results: 10,116 stool samples were collected from 5116 AFP cases by Chinese Polio Laboratories Network in 2008, and viral isolation and identification of all stool samples were done according to 4th World Health Organization (WHO) Polio Laboratory Manual. The rate of viral isolation and identification performed within 28d was 94.9%. 189 polioviruses (PV) and 597 of non-polio enteroviruses (NPEV) were isolated from AFP cases, the isolatien rates were 3.72% and 11.74% respectively. 251 polio positive isolates were sent to NPL from 31 provincial polio laboratories. There were 318 single serotype PVs were performed VPI sequencing. And no wild polioviruses and Vaccine-derived Polioviruses (VDPVs) were found in 2008. NPL passed the proficiency test and got full accreditation for on-site review by WHO experts in 2008. All 31 provincial Polio laboratories passed the proficiency test with the same panel as NPL, and 13 provincial Polio laboratories joined and passed the on-site review by WHO experts., Conclusion: The running status of Chinese Polio Laboratories Network was good, polio-free status was maintained in China in 2008. The Chinese polio laboratories network running is normaly, the laboratory surveillance system was sensitive and laboratory data were provided for maintaining the polio-free status in China.

Objective: To study the molecular characteristics of type 1 poliovirus isolated from the acute flaccid paralysis (AFP)surveillance system in China in 2009, to provide a scientific basis for maintaining polio-free status for China., Method: Polymerase chain reaction (RT-PCR) method was used to amplify the VP1 code region of all the type I poliovirus, and the VP1 coding region of the isolated stains was sequenced and analyzed, the hot-spots and nuerovirulence determinant were analyzed. The phylogenetic tree was constructed based on VP1 region to analyze the evolutionary relationship between the strains., Result: The results of VP1 sequencing showed that no wild strains or vaccine-derived poliovirus (VDPVs) were detected. However, five pre-VDPVs were found. And nucleotide sequences of two isolates were in high degree of similarity (100%). Sequence alignment showed that two nucleotides in the VP1 region. nt2747 and nt2749 were two mutation hot spots., Conclusion: According to the epidemiological and laboratory test results of two high variation strains, the short-term circulation may occur probably, and further research are needed. Meanwhile, the existence of mutation hot spots indicated that strains are easy to reverse into wild-type substitutions, and lead to a series changes of neurological and other virulence when the strains are under selective pressure.

Objective: Analysis of epidemiology of 4 clustered high risk acute flaccid paralysis(AFP) cases reported by Shanxi province in 2006 and VP1 gene characteristic for type III poliovirus isolated from the four AFP cases., Methods: Virus isolation and identification were conducted according to the 4th edition of WHO polio laboratory manual. The sequence of VP1 region were amplified and sequenced. The phylogenetic trees based on VP1 region were constructed., Result: Three of four high risk AFP cases were suspected as vaccine associated paralysis poliomyelitis (VAPP), the onset date of them were close. VP1 sequencing of the four type III isolates revealed that the identity were 99.7%, 99.9%, 99.4% and 99.9% respectively compared with vaccine reference strain-BJOPV3. According to WHO criteria, the four isolates were identified as type III vaccine-related poliovirus. Phylogenetic analysis based on VP1 coding sequence showed that the four type III poliovirus were not related significantly. The type III poliovirus isolated from 3 suspected VAPP cases shared one nucleotide mutation at 2637 (C-->U), which result in the amino acid mutation from Val into Ala., Conclusion: The improvement of laboratory surveillance for clustered high risk AFP cases should be strengthened so as to detect and prevent poliovirus circulation timely.

Objective: In order to provide the evidence for polio free status, the VP1 gene characteristic analysis of poliovirus isolated from acute flaccid paralysis (AFP) cases and close contacts were conducted in Hebei Province during 2007-2008., Methods: Virus isolation and identification were conducted according to the 4th edition of WHO polio laboratory manual. The sequence of VP1 region were amplified and sequenced. The phylogenetic trees based on VP1 region were constructed., Result: The total number of poliovirus isolates were 42. Most isolates were type II and III. No wild poliovirus and vaccine derived poliovirus (VDPVs) was detected., Conclusion: Gene characteristic of VP1 region of poliovirus can be used to identify the polio virus transmission and guide the work of immunization program.

Background: The virological surveillance of acute flaccid paralysis (AFP) is a critical component of the initiative of the World Health Organization (WHO) to eradicate poliomyelitis worldwide. Furthermore rapid methods are needed either to detect or rule out the presence of polioviruses during the late stages of eradication, especially in polio-free areas., Objectives: The aim of this study was to evaluate a fast protocol combining one passage (5 days) in cell culture followed by RT-PCR and molecular typing in order to detect and type poliovirus (PV) and other enteroviruses associated with AFP cases., Study Design: A total of 216 fecal suspensions from AFP suspected cases were tested by using this approach and compared with the WHO gold standard., Results: Using the WHO protocol enterovirus was detected in 12 out of the 216 AFP samples (5.55%) while with the proposed protocol enterovirus was detected in 15 out of the 216 AFP samples (6.94%). The additional positive samples detected by the proposed method were classified as non-polio enteroviruses (NPEV)., Conclusions: The proposed protocol showed higher sensitivity than the WHO gold standard, reducing the entire process of identification and typing of the isolates from the typically 14-21 days to only approximately 6-8 days.

Enterovirus 71 (EV71) and coxsackievirus A16 (CVA16), belonging to family Picornaviridae, genus Enterovirus, species A, are causative agents of hand-foot-mouth disease (HFMD). Infections involving EV71, but not CVA16, can progress to severe neurological disease, including aseptic meningitis, encephalitis, acute flaccid paralysis and neurogenic pulmonary edema. EV71 is thus considered to be a neuropathogenic virus and EV71 outbreak has become a major public health concern. Human RD cells are highly susceptible to EV71, while mouse L929 cell are not. We established mouse cell lines that acquired EV71-susceptibility by transfecting human genomic DNA. We succeeded in identifying a human gene, scavenger receptor B2 (SCARB2), integrated in one of the transformant cells by microarray analysis and showed that SCARB2 can serve as a EV71 receptor. I will summarize this result, background and the methodology of the study.

In order to study the genotypes and molecular evolution of human enterovirus (HEV) A species in Shandong Province, Stool samples were collected from AFP and HFMD patients in Shandong Province and virus isolation was performed. Reverse Transcription-Polymerase Chain Reactions (RT-PCR) specific for EV71 and CVA16 were performed with the virus isolates from HFMD patients. Positive isolates were selected for entire VP1 coding gene amplification and sequencing. Isolates with negative PCR results and isolates from AFP patients were selected for entire VP1 coding gene amplification and sequencing using primers specific for HEV A species. Phylogenetic tree was constructed among these VP1 nucleotide sequences and of other strains. Altogether 293 strains classified into 8 genotypes were isolated. The homologous comparison and phylogenetic analysis showed Shandong strains were distinct with prototype strains in every genotype. This report presents an overview of HEV-A in Shandong Province.

Objective: Study on the epidemiological characteristics of poliomyelitis virus in Yunnan, from 2003 to 2007., Methods: Surveillance data of acute flaccid paralysis (AFP) cases from year 2003 to 2007 was gathered. All the stool specimens were identified to contain polio virus., Results: 1171 AFP cases were reported. Out of the total number of 1138 stool specimens from 2003 to 2007, 57 cases showed polio virus (5.0%), 159 showed NPEV (14.0%), 922 cases showed virus negative. In those virus, polio type II took the lead (31.6%). 57 AFP cases appeared in 37 (28.7%) counties in Yunnan. Most of the cases were under 2 years of age. 29 cases had taken more than 3 OPV (oral poliovaccine) dosages and 41 cases had fever before paralysis occurred. Most of the cases appeared paralysis on single lower limb, but 26 cases leaving deformity. Significant difference was found between the two groups: having received vaccination more than 3 OPV dosages or less than 3 dosages., Conclusion: High quality AFP epidemiological and laboratory surveillance program, together with OPV routine and supplemental immunization strategy to cover the poorly immunized area/population appeared to be most effective.

Enterovirus 71 (EV71) has emerged as a major cause of neurological threat in the world following the eradication of poliovirus. Most EV71 infections commonly result in hand-foot-mouth disease or herpangina, and some cases are associated with brainstem encephalitis and acute flaccid paralysis. Mortality was high in EV71 brainstem encephalitis complicated with pulmonary edema, particularly in children below 5 years of age. Destruction of vasomotor in the brainstem by EV71 produces autonomic nervous system dysregulation prior to the pulmonary edema. The pulmonary edema is the result of increased pulmonary vascular permeability caused by the direct brainstem lesions and/or a systemic inflammatory response syndrome produced by the release of cytokines and chemokines. There is currently no specific antiviral agent to treat or vaccine to prevent EV71 diseases. Treating severe EV71 brainstem encephalitis patients with intravenous IgG and milrinone is associated with significantly decreased mortality by attenuated sympathetic activity and cytokine production.

In 1992 surveillance of acute flaccid paralysis (AFP) cases was introduced in Malaysia along with the establishment of a national referral laboratory at the Institute for Medical Research. The objective of this study was to determine the incidence, viral etiology and clinical picture of AFP cases below 15 years of age, reported from 2002 to 2007. Six hundred seventy-eight of 688 reported cases were confirmed as AFP by expert review. The clinical presentation of acute flaccid paralysis in these cases was diverse, the most commonly reported being Guillian-Barre syndrome (32.3%). Sixty-nine viruses were isolated in this study. They were Sabin poliovirus (25), Echovirus (22), Cocksackie B (11), EV71 (5), Cocksackie A (1), and untypable (5). Malaysia has been confirmed as free from wild polio since the surveillance was established.

The recent epidemic of chikungunya fever (2005-2006) in India has affected millions of people. The Andaman and Nicobar Islands, an archipelago situated in the Bay of Bengal 1200 km from peninsular India, also witnessed an outbreak of chikungunya fever starting in July 2006 which affected thousands of people. Chikungunya fever classically manifests as high fever, myalgia, arthralgia and arthritis and in a certain percentage of cases with maculopapular rashes. However, deviation from the classical clinical features of chikungunya fever was reported in the earlier and recent epidemics. During the recent epidemic in the Andaman and Nicobar Islands we came across ten cases of flaccid limb weakness following symptoms and signs suggestive of chikungunya fever. In four subjects we confirmed the diagnosis of chikungunya virus infection by serological method (IgM ELISA method). This is the case report of those four subjects.

The evaluation of the contribution of neurological dengue in suspected central nervous system (CNS) viral infections is essential to better understand the impact of neurological dengue on morbidity and mortality in dengue endemic regions such as Jamaica. For this study 401 cases of suspected viral CNS infections were investigated for evidence of dengue infection. The frequency of neurological dengue among these CNS cases was found to be 13.5% (54/401). Fifty-three cases were confirmed serologically by haemagglutination inhibition assay (HI) and IgM antibody (ELISA) and the virus was isolated in one case only. Clinical manifestations among dengue positive CNS cases included encephalitis in 51.8% (28/54), meningitis in 33.3% (18/54), seizures in 11.1% (6/54) and acute flaccid paralysis/Guillain-Barré syndrome in 3.7% (2/54). The clinical diagnosis of dengue neurological infection corresponded with laboratory confirmation in 22.2% (12/54) of cases only. Deaths occurred in 3.7% (2/54) of cases and were associated with patients with dengue neurological infection. The high risk of dengue among patients with suspected viral CNS infections in this study supports the need for an increased index of suspicion of dengue in patients presenting with neurological manifestations in dengue endemic countries.

In July 2007, wild poliovirus type 1 was isolated from a patient suffering poliomyelitis in Melbourne, Australia with onset in Pakistan. The imported case of polio demonstrates the ongoing risk faced by polio-free countries until the global certification of polio eradication. The poliovirus was detected by the National Poliovirus Reference Laboratory (NPRL) for Australia; accredited by the World Health Organization (WHO). The NPRL acts as the national laboratory for the Pacific Islands, Brunei Darussalam and Papua New Guinea. Additionally, the NPRL functions as a regional reference laboratory for the WHO Western Pacific Region. The NPRL, in collaboration with the Australian Paediatric Surveillance Unit, co-ordinates surveillance for acute flaccid paralysis (AFP), a major clinical presentation of poliovirus infection. After classification of AFP cases by the Polio Expert Committee, the non-polio AFP rate for Australia in 2007 was 0.65 per 100,000 children aged less than 15 years, below the performance indicator of 1.0 per 100,000 set by the WHO. Adequate faecal sample collection totalled 48% (13/27) of eligible AFP notifications, below the 80% performance indicator recommended by the WHO. During 2007, 119 specimens were referred to the NPRL, 70 from AFP cases and 49 from other sources, including contacts of the wild poliovirus importation, all negative for poliovirus infection. Coxsackievirus A4 was isolated from 1 case and adenovirus from 2 cases. During 2007, 1313 cases of poliomyelitis due to wild poliovirus infection were reported world-wide: 1207 occurring in the 4 remaining polio endemic countries and 106 cases reported in 5 non-endemic countries.

Objective: To determine some virulent trait-related properties of poliovirus isolates from children with acute flaccid paralysis following vaccination with oral polio vaccine (OPV)., Design: Six polioviruses earlier characterised into wild, vaccine-derived and OPV-like were studied using the plaque morphology and growth kinetics at supra-optimal temperature., Setting: Department of Virology, University of Ibadan, Nigeria., Subjects: Polio isolates from six children who developed acute flaccid paralysis following vaccinations with various doses of OPV were used. All the children were located in the Northern part of the country where poliovirus is still circulating., Main Outcome Measures: The two vaccine-derived polioviruses acquired wild type characteristics., Results: All the six poliovirus isolates developed different forms of plaques ranging from tiny, small and large. The plaque formed could however not be used to identify the different isolates. Growth of the different isolates at supra-optimal temperature showed that the three wild polioviruses grew to a higher titre when compared with the Sabin 2 control. The two vaccine derived isolates behaved like the wild poliovirus while the OPV-like virus acquired an intermediate characteristics between wild and sabin., Conclusion: The wild polioviruses represented in this study are among the last vestiges of the circulating polioviruses found in the world. It is possible that the observed biological properties of wild types 1 and 3 described in the study are typical of the West African polioviruses. These properties will provide useful previews to the final identification of some important clinical isolates especially type 1 which may grow rapidly in cell culture.

Japanese encephalitis (JE) is an endemic disease in Taiwan. Acute JE virus infection characterized by acute flaccid paralysis in an adult has never been reported in Taiwan. We report a young adult man who received four doses of JEV (Nakayama strain) vaccination in childhood, but still developed acute JE virus infection, characterized with acute flaccid paralysis.He presented with fever, headache, progressive muscle weakness, and respiratory paralysis requiring mechanical ventilator. Deep tendon reflexes were decreased except for the Achilles reflex. After supportive care, he was weaned from the mechanical ventilator and at discharge 1 month later, his muscle power level and deep tendon reflexes recovered partially. The diagnosis of JE was based on the presence of anti-JE virus IgM in the CSF and seroconversion of IgM and IgG by the ELISA method. Electrophysiological findings were described. From the experience of this case, we caution that a history of vaccination for JE with the Nakayama strain may not provide a complete protection against natural infection in the community; and in Taiwan or any area where JE remains an endemic disease, Japanese virus encephalitis infection should be considered as a differential diagnosis in any adult presenting with acute flaccid paralysis.

Until 2008 poliomyelitis was controlled in Romania by predominantly using Oral Poliovirus Vaccine Sabin (OPV); the alternative vaccination schedule (IPV formalin Inactivated Poliovirus Vaccine/OPV) will be implemented starting September 2008. The vaccination coverage with 4 doses of TOPV (trivalent oral polio vaccine) in the first 14 months of life has been > 90% since 1980. In Romania, the risk of the Vaccine-Associated Paralytic Poliomyelitis cases (VAPP) decreased from less than 2 VAPP cases/year in the 1995-2006 interval to 0 VAPP cases in 2007. The serological study was performed in 2006-2007 only in cases with pair serum samples from 28 acute flaccid paralysis (AFP) cases (age = 3 months - 14 years) and from 45 facial paralysis (FP) cases (age -6 months - 4 years 9 months). A high level of vaccinal coverage was shown for all poliovirus serotypes: >95% in AFP serum samples investigated; and for FP serum samples investigated the levels of antibodies against poliovirus (PV) serotypes were 98% for PV type 1; 87% for PV type 2: and 89% for PV type 3. If the European region is polio free since 2002, the risk of wild PV importation from endemic region remains present. The laboratory capacity for the fast detection and molecular investigations of the emergence of the new epidemic strains and a high level of population immunity must be maintained. A national seroprevalence study concerning all three PV serotypes must be performed.

Background and Purpose: The incidence of West Nile virus (WNV) has increased in the United States since 1999. A small percentage of people with WNV develop West Nile neuroinvasive disease (WNND) with encephalitis and flaccid paralysis. The purpose of this report is to describe the physical therapist management and outcomes for a patient with WNND and the therapist's efforts to use an evidence-based practice approach in the management of a patient with this disease., Case Description: The patient was an active 55-year-old woman in excellent health who became acutely ill with asymmetrical lower-extremity weakness. The physical therapist reviewed the available literature, consulted with medical and physical therapist experts and the patient, and elected to use a poliovirus "period of recovery" approach combining intensive strengthening and monitoring of fatigue., Outcomes: The patient progressed from an initial nonambulatory status to ambulation with a single-point cane at week 18 after onset of symptoms. She began to ambulate without an assistive device by week 20. The patient returned to work part-time by week 22 and full-time by week 43., Discussion: These outcomes demonstrate the recovery of a patient with WNND after an intensive strengthening program.

A man in his 70s presented for acute rehabilitation with severe acute flaccid asymmetric weakness in both lower limbs. Cerebrospinal fluid and serum immunoglobulin M titers were positive for West Nile virus. Electrodiagnostic studies demonstrated severe diffuse motor axonopathy consistent with an anterior myelitis. Electrodiagnostic and clinical improvements were monitored. Electrodiagnostic testing at 6 and 18 mos demonstrated continuing reinnervation; nascent voluntary motor unit action potentials were first noted proximally and, at 18 mos, distally in the left lower limb, including muscles in which motor unit potentials were not initially noted. Corresponding clinical improvements, though slow, were demonstrated even at 1(1/2) yrs after onset. Thus, motoric changes after West Nile virus-associated anterior myelitis need to be monitored over a prolonged time period to allow accurate assessment of prognosis for recovery in rehabilitation programs.

Objective: To study the circulating vaccine-derived poliovirus (cVDPVs) that occurred in Zhenfeng county, Guizhou province in 2004 and to discover wild-poliovirus, vaccine-derived poliovirus (VDPVs) and other vaccine-associated poliovirus which could cause clinical poliomyelitis., Methods: Field epidemiological studies at the epidemic area and collecting acute flaccid paralysis (AFP) case and contact stool specimen for virus identification and nucleotide sequencing. Analysis on data related to annual reports on stool specimens surveillance which involved AFP case and contacts in the resent years in Zhenfeng county., Results: Type-I VDPVs had been isolated from 2 AFP cases and 3 contact stool specimen in Wanlan village of Zhenfeng. After the first cVDPVs case was identified, there were 3 cases identified of having other vaccine-associated poliovirus of type-I or type-II in the 5 case of AFP that met the criteria of clinical poliomyelitis. The result of virological surveillance on polio showed that the EV isolation rate (55.1%) of Zhenfeng county was higher than the rate from the whole province of the same year (23.2%). The poliovirus (PV) isolation rate (36.8%) was obviously higher in 2004 than in the previous years. In the 16 PVs strains, the type-I accounted for 43.8% which was significantly higher than the average level (18.3%) from the whole province., Conclusions: Data indicated that the type-I VDPVs had been circulating (cVDPVs) in Zhenfeng county in Guizhou province. Clinical poliomyelitis was caused by non-VDPVs. The increased PV infection and the decreasing rate of vaccination in the general population were responsible for the epidemic of type-I cVDPVs at this time. Monitoring and evaluation on the rate of routine immunization program and prediction of the trend of epidemic should be strenthened.

Since the 1988 World Health Assembly resolution to eradicate poliomyelitis, the number of countries where polio is endemic has decreased from 125 in 1988 to six at the end of 2003. As part of the eradication strategy, a global surveillance system was established to 1) identify acute flaccid paralysis (AFP) cases in children aged < or =15 years and 2) deploy a network of accredited laboratories to perform virologic testing of stool specimens to determine whether the paralysis resulted from poliovirus infection. As AFP surveillance systems matured, countries increasingly applied AFP surveillance strategies and infrastructure to detect other diseases. This report describes the status of global AFP surveillance, including its expansion or use as a model in 131 (66%) of 198 countries for the reporting of measles and other vaccine-preventable diseases. As poliomyelitis is eradicated, AFP surveillance systems in these and other countries might be further expanded and adapted to improve the detection of and response to other diseases.

The Institute for Medical Research, Malaysia, was designated the National Reference Laboratory for Poliomyelitis Eradication (NRLPE) in 1992. Since then, our Polio Laboratory has collaborated actively with the Disease Control Division, Ministry of Health (MOH), Malaysia and WHO towards achieving polio eradication. Since 1992, the NRLPE has investigated 1,063 stool specimens from 641 acute flaccidparalysis (AFP) cases. One hundred and one enteroviruses were isolated from these specimens. Positive cell cultures were confirmed by microneutralization assay using standard WHO antisera. All enterovirus isolates were sent to the Victorian Infectious Disease Reference Laboratory in Melbourne, Australia, for further identification and poliovirus intratypic differentiation. Thirty-one out of these 101 virus isolates (30%) were polioviruses (PV) and the remaining 70 (70%) were non-polio enteroviruses (NPEV) which included coxsackie B viruses, echoviruses and enterovirus 71. Three of the poliovirus isolates were wild-type polioviruses isolated in 1992 which were the last wild-type polioviruses isolated in Malaysia. The rest were vaccine-related Sabin-like strains. Monthly reports of the virological investigation of AFP cases are sent to WHO and to the MOH, AFP control committee. The NRLPE continues to play an integral role in AFP surveillance and is committed to the WHO's goal of global polio eradication by the year 2005.

DBA/2 CrSlc mice infected with the D variant of encephalomyocarditis virus (EMC-D) (10 PFU/head) developed biphasic hind limb paralysis due to spinal cord lesion. The early phase lesion was characterized by demyelination with infiltration of macrophages in the funiculus lateraris and the late phase lesion by degeneration of motor neurons with infiltration of CD4(+) T cells in the cornu ventrale. In the present study, treatment with anti-Mac1 monoclonal antibody (MAb) or anti-CD4 MAb prior to virus infection (-3 to -1 days) reduced the early phase lesion and the incidence of the first paralysis. Signals of viral RNAs were observed only in a few oligodendrocytes in the funiculus lateraris. Treatment with anti-CD4 MAb from 31 to 33 days post infection when mice showed recovery from the first paralysis reduced the late phase lesion and prevented the second paralysis. Signals of viral RNAs were still detected in a few degenerated neurons in the cornu ventrale. These results indicate that while macrophages and CD4(+) T cells participate in the early phase lesion and paralysis and only CD4(+) T cells in the late phase lesion and paralysis.

Purpose: To report the first documented case of intrauterine transmission of West Nile virus (WNV) with resulting congenital chorioretinal scarring and central nervous system malformation in a newborn., Design: Case report., Methods: Ophthalmic findings and laboratory data in an otherwise presumed healthy 2-day-old female are presented. The infant's mother developed paraplegia due to WNV during the second trimester of her pregnancy. The newborn's external and general physical examination were unremarkable., Results: Ophthalmic examination disclosed marked chorioretinal changes, and magnetic resonance imaging of the brain demonstrated severe abnormalities. Serology for WNV was positive. Other causes of congenital chorioretinal changes were ruled out with the appropriate serology., Conclusions: Intrauterine transmission of WNV may result in significant ocular and neurologic morbidity. Titers for this important and emerging viral pathogen should be obtained when standard serologies are negative in an infant with congenital chorioretinal scarring.

The neuromuscular aspects of West Nile virus (WNV) infection have not been characterized in detail. We have studied a group of six patients with proven WNV infection. All cases presented with acute, severe, asymmetric, or monolimb weakness, with minimal or no sensory disturbance after a mild flu-like prodrome. Four cases also had facial weakness. Three of our cases had no encephalitic signs or symptoms despite cerebrospinal fluid pleocytosis. Electrophysiological studies showed severe denervation in paralyzed limb muscles, suggesting either motor neuron or multiple ventral nerve root damage. This localization is supported further by the finding of abnormal signal intensity confined to the anterior horns on a lumbar spine magnetic resonance imaging. Muscle biopsies from three patients showed scattered necrotic fibers, implicating mild direct or indirect muscle damage from the WNV infection. In summary, we describe a group of patients with acute segmental flaccid paralysis with minimal or no encephalitic or sensory signs. We have localized the abnormality to either the spinal motor neurons or their ventral nerve roots. It will be important for physicians to consider WNV infection in patients with acute asymmetric paralysis with or without encephalitic symptoms.

We report the virological and clinical features of 8 children who presented with adenovirus-associated acute flaccid paralysis (AFP) during an epidemic of enterovirus type 71 (EV71)-associated hand-foot-and-mouth disease (HFMD) in Sarawak, Malaysia, in 1997. Neutralization tests and phylogenetic analysis revealed adenovirus type 21 (Ad21), although DNA restriction digests suggested that this virus was different from the prototype Ad21. Four children had upper-limb monoparesis, 2 had lower-limb monoparesis (one of whom had changes in the anterior spinal cord noted on magnetic resonance imaging), and 2 had flaccid paraparesis. At follow-up, 4 children were noted to have made full recoveries and 3 had residual flaccid weakness and wasting. Neurophysiological investigation revealed a mixture of axonal and demyelinating features in motor and sensory nerves, with denervation. These findings suggest that Ad21 might cause AFP by anterior horn cell damage or neuropathy of the brachial or lumbosacral plexus. The occurrence of these unusual adenovirus infections during an outbreak of EV71-associated HFMD suggests that an interaction between the 2 viruses may have occurred.

Acute flaccid paralysis is the main clinical manifestation of poliomyelitis. Faecal specimens from cases of acute flaccid paralysis in Australia are referred to the National Poliovirus Reference Laboratory for virus culture to determine if poliovirus is the causative agent. Isolations of poliovirus are tested to determine whether they have characteristics of the Sabin oral polio vaccine virus strains or wild type polioviruses. In 2002, a poliovirus type 3, which tested as Sabin vaccine-like, was isolated from an Australian patient with acute flaccid paralysis. A non-polio enterovirus, Echovirus type 18, was isolated from the faecal specimens of another case of acute flaccid paralysis. In the same period, the laboratory identified 35 Sabin-like polioviruses from 52 referred specimens and isolates from cases without acute flaccid paralysis. Australia is a member nation of the World Health Organization's Western Pacific region that was declared free of endemic wild poliovirus in October 2000. Poliomyelitis remains endemic in three of the WHO regions of the world and wild poliovirus may be re-introduced to Australia. While the number of polio-endemic countries has been reduced to seven, the total number of wild polioviruses identified increased in 2002 compared to 2001 due to a sharp rise in isolations of wild virus from Northern India. Until global eradication of poliomyelitis is achieved, it is essential that a high level of poliovirus vaccination coverage, and surveillance for cases of acute flaccid paralysis, be maintained in Australia.

West Nile virus (WNV) infection can cause severe, potentially fatal neurologic illnesses including encephalitis and meningitis. Acute WNV infection also has been associated with acute flaccid paralysis (AFP) attributed to a peripheral demyelinating process (Guillain-Barré Syndrome [GBS]), or to an anterior myelitis. However, the exact etiology of AFP has not been assessed thoroughly with electrophysiologic, laboratory, and neuroimaging data. This report describes six cases of WNV-associated AFP in which clinical and electrophysiologic findings suggest a pathologic process involving anterior horn cells and motor axons similar to that seen in acute poliomyelitis. Clinicians should evaluate patients with AFP for evidence of WNV infection and conduct tests to differentiate GBS from other causes of AFP.

Since the World Health Assembly resolved in 1988 to eradicate poliomyelitis, the estimated number of polio cases worldwide has declined >99%. Angola began polio eradication activities in 1996. Although polio eradication efforts have been hampered by the country's 27-year-long civil war, both the incidence of polio cases and the geographic circulation of poliovirus in Angola have decreased substantially. The cessation of hostilities on April 4, 2002, presents a new opportunity to reach populations that had been inaccessible and undervaccinated previously. This report summarizes progress made during January 1998-June 2002 and highlights the remaining challenges to eradicating polio in Angola.

Since 1988, when the World Health Assembly resolved to eradicate poliomyelitis worldwide, the estimated global incidence of polio has decreased 99%. Pakistan began polio eradication activities in 1994 and Afghanistan in 1997. Although polio remains endemic in the two countries, both the incidence and the geographic distribution of poliovirus have been reduced substantially. This report summarizes progress toward eradicating polio in Pakistan and Afghanistan during January 2000-April 2002. Both countries aim to stop transmission of poliovirus by the end of 2002; however, the unstable security situation in the region might threaten this success.

Two male patients aged 40 and 45 years with HIV infection and paraplegia are presented. The two had sub-acute onset paraplegia with a sensory level, which developed 10 days after herpes zoster dermatomal rash. They both had asymmetrically involvement of the lower limbs. Investigation including imaging of the spinal cord did not reveal any other cause of the neurological deficit. The two responded very well to treatment with acyclovir. Herpes zoster myelitis is a condition likely to rise with the upsurge of HIV infection and there is a need to identify the condition early. We also review the literature on the subject.

Objective: Human enteroviruses are the major cause of aseptic meningitis and also cause a wide range of other acute illnesses, including neonatal sepsis like disease, meningitis, acute flaccid paralysis and acute hemorrhagic conjunctivitis. Infection in neonates is particularly life threatening., Methods: Stool samples of 523 children (age < 4 years) showing symptoms of acute flaccid paralysis (AFP) were studied. National Polio Surveillance Project workers from different parts of Uttar Pradesh and Bihar collected the samples during June to October 1998. Non-polio enteroviruses (NPEV) were isolated in 191 cases only, by cell culture based neutralization assay. These NPEV isolates were further studied to find the frequent enterovirus serotype detected in stool of children having AFP., Results: Data generated will help future studies on NPEV serotypes circulating in this area., Conclusion: In addition it may reduce unnecessary hospitalization, allow immune globulin batches of high titres to frequently circulating serotypes, to be reserved for intravenous therapy of neonates and guide the formulation of antigens for rapid and less expensive diagnosis.

Accidental B virus (Herpesvirus simiae) infection of human beings working with macaques is frequently fatal. However, the pathogenic potential of other similar simian alphaherpesviruses, such as the squirrel monkey virus Herpesvirus saimiri (HVS1), is virtually unknown. As part of an effort to develop a murine model for infections with these agents, Balb/c mice were inoculated intramuscularly in the left hindlimb with 10 to 10(6) plaque forming units (PFU) of HVS1. After observation for clinical signs of infection for 21 days, mice were killed and specimens collected for serology and histopathology. Mice receiving 510(3) PFU of HVS1 exhibited severe, pruritic, ulcerative skin lesions near the site of inoculation and developed unilateral or bilateral hindlimb paralysis with severe muscle atrophy. Histological lesions were characterized by a necrotizing dermatitis and folliculitis. Spinal cord lesions consisted of a non-suppurative myelitis affecting primarily the ipsilateral dorsal horn of the thoracolumbar spinal cord with occasional extension to ventral and contralateral spinal cord regions. Immunohistochemical labelling confirmed the presence of viral antigen within the lesions, and anti-HVS1 IgG concentrations were related to the occurrence of disease. HVS1 infection in some mice extended from the ipsilateral dorsal horn and funiculus into the ventral and contralateral grey and white matter, resulting in bilateral hindlimb paralysis. Thoracolumbar spinal cord lesions resolved without continued spread of the virus to cranial nervous system structures, i.e., cervical spinal cord and brain., (Copyright Harcourt Publishers Ltd.)

The authors describe one case of acute flaccid paralytic of lower limbs in a 10-year-old boy with Echovirus 7 isolated in the stool and a high titer of homologous antibodies (> or = 1,024). At the final stage of poliomyelitis program eradication, paralysis associated with non polio enterovirus may replace cases of paralytic poliomyelitis. In the present study, the authors highlight the needs to confirm virologically all suspect cases of acute flaccid paralytic. Aetiological function of the virus isolated and interpretation of the diagnostic methods are discussed.

Bovine paraplegic syndrome (BPS) is a debilitating cattle disease of unknown origin that is characterized by leukocytosis, lymphocytopenia and monocytopenia. The major clinical signs are difficulties in locomotion affecting hind limbs, hypoalgesia in the hind quarters, posterior paralysis and death within 72 to 96 hours after recumbency. To investigate the aetiological basis of BPS, we examined a possible association of the syndrome with infection by bovine immunodeficiency virus (BIV), a lentivirus implicated in immune system dysfunction and central nervous system lesions in cattle. Serum samples (n = 1,278) were collected from both healthy and BPS-prevalent cattle herds in Venezuela, and organ extracts were prepared from euthanized animals (n = 11) suspected of having BPS. Sera were analysed for reactivity to recombinant BIV and bovine leukaemia virus gag precursor proteins by immunoblot procedures. Serum reactivity to BIV ranged from 12 to 66% between groups of BPS prevalent herds. The percentage of samples reactive to BLV antigen was much lower (2 to 17%). Rabbits inoculated with extracts from BPS-afflicted animals exhibited an anamnestic immune response to BIV antigens as well as the presence of BIV gag antigens in their tissues. We present evidence for a possible association between BPS disease and a viral agent related to BIV. The role of BIV, in combination with malnutrition, in BPS is discussed.