Polioviruses and other enteroviruses isolated from faecal samples of patients with acute flaccid paralysis in Australia, 1996-2004

Background: Acute flaccid paralysis (AFP) is the most common clinical presentation of acute poliovirus infection, occurring in 0.1-1% of infected cases. AFP surveillance has been used world-wide to monitor the control and eradication of circulating wild poliovirus. This study aims to review the significance of all enteroviruses, including polioviruses, isolated from patients with AFP in Australia between 1996 and 2004. Methods: We undertook a retrospective review of all notified cases of AFP, aged 0-15 years and resident in Australia at the time of notification. We reviewed all available clinical and virological data for these cases and all records of the Polio Expert Committee, which determined the final classification for all cases. Results: There were 335 notified cases that satisfied the case definition for AFP, 162 (48%) of whom had at least one faecal sample tested. Enteroviruses isolated from the faeces of 26 (16%) of the 162 cases were Coxsackie A24, Coxsackie B5, enterovirus 71, enterovirus 75, echovirus 9, echovirus 11 and echovirus 18. In addition, one or more polioviruses were isolated from the faeces of seven patients. Six of seven polioviruses were characterised as Sabin-like, one was not characterised, but all were considered to be incidental isolates. Five of these cases were classified as infant botulism, one case as transverse myelitis and one as a focal mononeuropathy. Conclusion: With the eradication of circulating wild polioviruses, other enteroviruses are being more commonly identified as the cause of polio-like illnesses. In the polio end game, when there is increased testing for polioviruses, it is important to consider infant botulism as a differential diagnosis in cases presenting with AFP.

Molecular and seroepidemiologic studies of Enterovirus 71 infection in the State of Pará, Brazil

In many countries, the Enterovirus 71 (EV-71) Picornaviridae family is associated to hand, foot and mouth disease in addition to acute neurological diseases while in Brazil these viruses are more closely associated to the latter group. The aim of this research was to use the first EV-71 isolate of the Northern region of Brazil in molecular and seroepidemiologic studies. Two (2.2%) out of 88 stool samples (44 cases of AFP), collected from January 1998 to December 2000 were positive for EV-71 isolation (73442/PA/99). Nucleotide sequence of the gen that codifies the VP1 protein showed that isolate 73442/PA/99 was similar to the EV-71 strains belonging to genotype B - more closely identified with EV-71 from North America. Neutralization test with 389 sera samples collected from January 1998 to November 2001, from individuals ranging from 0 to 15 years of age living in the city of Belém, State of Pará showed the following results in relation to isolate 73442/PA/99 and prototype BrCr: a total of 207 individuals (53.2%) had neutralization antibodies to both viruses, 167 (42.9%) had no antibodies and 15 showed the presence of neutralizing antibodies to one of the two viruses. Only 20.2% of the children aged 0 to 3 had neutralizing antibodies to EV-71, indicating that these children were more susceptible to the infection. Both the seroprevalence study and VP1 sequencing were important to demonstrate the spread and the molecular pattern of the EV-71 circulating in the Northern Region of Brazil.

Intratypic differentiation of polioviruses isolated from suspected cases of poliomyelitis in Brazil during the period of 1990 to 1993

This study analyzed 3129 fecal samples derived from 1626 patients with sudden onset acute flaccid paralysis clinically compatible with poliomyelitis. The samples were collected in the period ranging from January 1990 to September 1993 in all regions of Brazil. Among the 1626 cases studied, 196 had isolation of poliovirus. Nevertheless, it was observed that some factors influenced the isolation rate and the intratypic characterization of these polioviruses. No cases of acute flaccid paralysis has been found to be etiologically related with wild polioviruses.

Neutralizing Antibodies to Enterovirus 71 in Belém, Brazil

Non-polio enteroviruses (Coxsackievirus A, Coxsackievirus B, Echovirus and EV 68-72) which belong to the enterovirus (EV) genus, Picornaviridae family, may be responsible for acute flaccid paralysis, aseptic meningitis, myocarditis, hepatitis, pleurodinia, neonatal sepsis, hand, foot and mouth disease (HFMD) even though 50-80% of infections are asymptomatic. EV 71 has been responsible for outbreaks and epidemics of HFMD and acute neurologic disease justifying its study in our country. The aim of this study was to detect neutralizing antibodies (NtAb) to EV 71 in individuals up to 15 years of age living in Belém, State of Pará, northern Brazil. Serum samples from 238 patients attending the Virology Sector of Evandro Chagas Institute in Belém, Brazil, were analyzed using microneutralization tests that included RD cells and BrCr strain. Overall 40.8% (97/238) of tested samples had NtAb to EV 71. Regarding the distribution per age group, 85.2% (92/108) of patients aged 0-3 years had no NtAb to this virus and 69.2% of those 12 to15 years of age were seropositive. These results confirm that EV 71 infection occurs in the city of Belém; and that a high rate of individuals in this study were infected aged 3 years and over and, when aged 15 years nearly 70% had EV 71 NtAb.

Enterovirus 75 and aseptic meningitis, Spain, 2005.

Although most human enterovirus (EV) (genus Enterovirus, family Picornaviridae) infections are asymptomatic, they can cause upper respiratory illness, febrile rash, aseptic meningitis, pleurodynia, encephalitis, acute flaccid paralysis, and neonatal sepsislike disease (1). Most EVs have been implicated in aseptic meningitis, most notably echovirus (E) 30, 9, 6, and 11 and coxsackie B virus (CBV) type 5 (2); other serotypes are less frequently associated with neurologic disease.

A RT-PCR method for selective amplification and phenotypic characterization of all three serotypes of Sabin-related polioviruses from viral mixtures

Outbreaks caused by vaccine-derived polioviruses are challenging the final eradication of paralytic poliomyelitis. Therefore, the surveillance of the acute flaccid paralysis cases based on poliovirus isolation and characterization remains an essential activity. Due to the use of trivalent oral poliovirus vaccine (OPV), mixtures containing more than one serotype of Sabin-related polioviruses are frequently isolated from clinical samples. Because each poliovirus isolate needs to be individually analyzed, we designed polymerase chain reaction primers that can selectively distinguish and amplify a genomic segment of the three Sabin-related poliovirus serotypes present in mixtures, thus, optimizing the diagnosis and providing prompt information to support epidemiologic actions.

Limitations to global disease control

In October 2000, Australia was declared poliomyelitis-free” by the World Health Organisation. This declaration followed some extensive six years of surveillance of all cases of acute flaccid paralysis, by the Poliomyelitis Expert Surveillance Committee (Centre for Disease Control, Commonwealth Department of Health and Aged Care, Canberra), chaired by the author. There have been seven attempts in the history of the world to eliminate a disease from the earth’s surface. The dramatic failure of five of these, the success of global smallpox eradication, and current successes and difficulties in the case of attempts to eliminate poliomyelitis worldwide, lead one to an analysis of the factors which led both to success and to failure. The global eradication of a specific disease is one of the most important endeavours which the international community can undertake. This audit reviews the details of such approaches; that such might be used as tools for the future.

Bilateral Peripheral Facial Palsy And Mastoid Infiltration As Symptoms Of Relapsed Acute Myeloid Leukemia.

Although Bell's palsy (BP) is the most common cause of peripheral facial palsy (PFP), other etiologies merit investigation. A 60-year-old female patient presented with recurrent bilateral PFP. Although the patient had a history of acute myeloid leukemia (AML), she had initially been diagnosed with BP-related PFP and had been treated accordingly. When the PFP recurred, additional diagnostic tests were performed. The resulting immunohistochemical profile included CD3 positivity in a few reactive T lymphocytes; positivity for myeloperoxidase in atypical cells; and focal positivity for CD34 and proto-oncogene c-kit proteins in neoplastic cells, thus confirming the suspicion of mastoid infiltration caused by relapsed AML. In patients with neoplastic disease, a finding of PFP calls for extensive investigation in order to rule out the involvement of the temporal bone.

A simple, inexpensive and easily reproducible model of spinal cord injury in mice: Morphological and functional assessment

Spinal cord injury (SCI) causes motor and sensory deficits that impair functional performance, and significantly impacts life expectancy and quality. Animal models provide a good opportunity to test therapeutic strategies in vivo. C57BL/6 mice were subjected to laminectomy at T9 and compression with a vascular clip (30 g force, 1 min). Two groups were analyzed: injured group (SCI, n = 33) and laminectomy only (Sham, n = 15). Locomotor behavior (Basso mouse scale-BMS and global mobility) was assessed weekly. Morphological analyses were performed by LM and EM. The Sham group did not show any morphofunctional alteration. All SCI animals showed flaccid paralysis 24 h after injury. with subsequent improvement. The BMS score of the SCI group improved until the intermediate phase (2.037 +/- 1.198): the Sham animals maintained the highest BMS score (8.981 +/- 0.056). p < 0.001 during the entire time. The locomotor speed was slower in the SCI animals (5.581 +/- 0.871) than in the Sham animals (15.80 +/- 1.166), p < 0.001. Morphological analysis of the SCI group showed, in the acute phase, edema, hemorrhage, multiple cavities, fiber degeneration, cell death and demyelination. In the chronic phase we observed glial scarring, neuron death, and remyelination of spared axons by oligodendrocytes and Schwann cells. In conclusion, we established a simple, reliable, and inexpensive clip compression model in mice, with functional and morphological reproducibility and good validity. The availability of producing reliable injuries with appropriate outcome measures represents great potential for studies involving cellular mechanisms of primary injury and repair after traumatic SCI. (C) 2008 Elsevier B.V. All rights reserved.

Isolation of dengue 2 virus from a patient with central nervous system involvement (transverse myelitis)

A dengue fever case is described in a 58-year-old male patient with febrile illness and thrombocytopenia complicated by neurological involvement characterized by transverse myelitis followed by weakness of both legs and flaccid paralysis. Muscle strength was much diminished and bilateral areflexia was observed. Dengue 2 (DEN-2) virus was isolated and the patient sero-converted by hemagglutination-inhibition and IgM-ELISA tests. The RT-PCR test was positive to DEN-2 in acute phase serum and culture supernatant, but negative in the cerebrospinal fluid. After three weeks of hospitalization the patient was discharged. No other infectious agent was detected in the blood and cerebrospinal fluid samples. The patient had full recovery from paralysis six months after the onset of DEN-2 infection.

Experimental envenomation with Crotalus durissus terrificus venom in dogs treated with antiophidic serum - Part I: Clinical evaluation, hematology and myelogram

The present study aimed at evaluating clinical and laboratory aspects during experimental envenomation by Crotalus durissus terrificus in dogs treated with antiophidic serum. Twenty-one dogs were divided into three groups of seven animals each. Group I received 1mg/kg venom (sc); Group II received 1mg/kg venom (sc), 50mg antiophidic serum (iv), and fluid therapy including 0.9% NaCl solution (iv); and Group III received 1mg/kg venom (sc), 50mg antiophidic serum (iv), and fluid therapy including 0.9% NaCl solution containing sodium bicarbonate diluted to the dose of 4mEq/kg. The clinical signs of ataxia, sedation, flaccid paralysis, mydriasis, eyeball paralysis, mandible ptosis, sialorrhea, vomiting and diarrhea observed in the dogs were very similar to those observed in humans. The decrease in hemoglobin, hematocrit, erythrocyte, platelet and fibrinogen levels, prolongation of clotting time, prothrombin time (PT) and activated partial thromboplastin time (APTT), as well as hypocellularity in the bone marrow characterized anemia, thrombocytopenia and blood incoagulability, as well as hypofibrinogenemia and decreased bone-marrow activity. Important bleeding was not observed. Increased numbers of leukocytes and neutrophils and decreased numbers of lymphocytes and eosinophils characterized an acute inflammatory response and stress caused by generalized pain. The employed antiophidic serum was effective and all animals survived.

Comparative in vitro effects of closantel and selected beta-ketoamide anthelmintics on a gastrointestinal nematode and vertebrate liver cells

PNU-87407 and PrNU-88509, beta-ketoamide anthelmintics that are structurally related to each other and to the salicylanilide anthelmintic closantel, exhibit different anthelmintic spectra and apparent toxicity in mammals, The basis for this differential pharmacology was examined in experiments that measured motility and adenosine triphosphate (ATP) levels in larval and adult stages of the gastrointestinal nematode, Haemonchus contortus, and in a vertebrate liver cell line and mitochondria, PNU-87407 and PNU-88509 both exhibited functional cross-resistance with closantel in larval migration assays using closantel-resistant and -sensitive isolates of H, contortus. Each compound reduced motility and,ATP levels in cultured adult H. contortus in a concentration- and time-dependent manner: however, motility was reduced more rapidly by PNU-88509, and ATP levels were reduced by lower concentrations of closantel than the beta-ketoamides. Tension recordings from segments of adult H, contortus showed that PNU-88509 induces spastic paralysis, while PNU-87407 and closantel induce flaccid paralysis of the somatic musculature. Marked differences in the actions of these compounds were also observed in the mammalian preparations. In Chang liver cells, ATP levels were reduced after 3 h exposures to greater than or equal to 0.25 mu M PNU-87407 1 mu M closantel or 10 mu M PNU-88509, Reductions in ATP caused by PNU-88509 were completely reversible, while the effects of closantel and PNU-87407; were irreversible. PNU-87407, closantel and PNU-88509 uncoupled oxidative phosphorylation in isolated rat liver mitochondria, inhibiting the respiratory control index (with glutamate or succinate as substrate) by 50% at concentrations of 0.14, 0.9 and 7.6 mu M respectively.

Fatal monensin toxicity in a dog after chewing a bovine intra-ruminal slow-release device

A 20kg, 10-month-old male Kelpie developed a rapid onset of profound paresis progressing to flaccid paralysis and dyspnoea, followed by death about 36 hours after chewing on a partly discharged anti-bloat capsule from a dead cow. Intoxication by monensin in the capsule was considered the cause of death. No Lodes holocyclus were found on the dog. Evidence of muscle damage was seen in clinical biochemistry assays of plasma, but consent for necropsy was not obtained. The median lethal dose for Beagle dogs of the material contained in anti-bloat capsules is 0.5-1.0g. As this represents a serious toxicity risk if dogs chew these devises, the manufacturer includes a warning on potential dog toxicity in product literature.

Possible reasons for variation in Ixodes holocyclus toxicity

Tick paralysis caused by Ixodes holocyclus affects an estimated 20,000 domestic animals each year along the eastern coast of Australia (Stone 1988). Animals are presented with clinical signs ranging from mild paresis to ascending flaccid paralysis and varying degrees of respiratory and cardiac compromise. Mortality rates are significantly increased in animals presented with respiratory compromise compared to those animals without respiratory compromise, regardless of the degree of flaccid paralysis (Atwell et al 2001). Anecdotal evidence of ticks (collected from different sites in northern New South Wales) causing different clinical signs and mortality in hyper-immune dogs used for serum production, suggests that there may be a variation in toxin production and toxin content between individual ticks (Warne, N 2002 pers comm). This literature review suggests that two possible contributing factors to toxin variation may be the genetic variation within the I. holocyclus species and the variation in the host's response to tick feeding.

Type C botulism in swine fed on restaurant waste

The paper addresses the epidemiologic data of the death of pigs during the period of 2002 to 2009 following the ingestion of botulinum neurotoxin type C. This neurotoxin was present in food residues originating from restaurant and hotel kitchens, stored in barrels without shelter from the sun and administered in a collective trough without prior thermal treatment. Animals which died at different ages showed clinical signs of botulism characterized by flaccid paralysis, weight loss, anorexia, weakness, lack of coordination, locomotion difficulties with the evolution of lateral recumbency with involuntary urination and defecation. No alterations were observed at postmortem and histological examination. The bioassay with serum neutralization in mice was carried out on samples of intestinal contents from pigs affected and revealed the presence of large quantities of botulinum toxin type C.