Diagnosis of Porcine teschovirus encephalomyelitis in the Republic of Haiti

Abstract

Abstract. In February and March 2009, approximately 1,500 backyard pigs of variable age became sick, and approximately 700 of them died or were euthanized in the Lower Artibonite Valley and the Lower Plateau of the Republic of Haiti. The main clinical sign was posterior ataxia followed by paresis and/or paralysis on the second or third day of illness. No gross lesions were observed at postmortem examinations. The morbidity and mortality were approximately 60% and 40%, respectively. Diagnostic samples (whole blood, brain, tonsil, lymph nodes, spleen, and lung) were negative for Classical swine fever virus and African swine fever virus. Porcine teschovirus type 1 was detected by reverse transcription polymerase chain reactions in brain samples. Results of virus isolation, electron microscopy of virus particles, histopathological analysis on brain tissues, nucleic acid sequencing, and phylogenetic analysis of the viral isolate supported the diagnosis of teschovirus encephalomyelitis. The outbreak of the disease in Haiti is the first appearance of the severe form of teschovirus encephalomyelitis in the Americas. This disease poses a potential threat to the swine industries in other Caribbean countries, as well as to Central and North American countries.

Viruses associated with congenital tremor and high lethality in piglets

“…However, in previous reports of APPV‐induced CT, there were no descriptions of neuronal necrosis. Alternatively, the neuronal necrosis, colonic oedema and/or atrophic enteritis observed in the piglets in this study have been previously described in cases of encephalomyelitis associated with PTV infection (Deng et al., ; Salles et al., ; Yamada et al., , ).…”

Paralysis in pigs with spinal cord injury due to porcine circovirus type 2 (PCV‐2) infection

“…Teschen disease and selenium poisoning are among these conditions, but in both these diseases, pathological findings are distinct from those observed in the spinal cord in association with PCV-2 infection. In pigs with Teschen disease, the lesions are characterised by non-suppurative meningoencephalomyelitis with perivascular cuffing by lymphocytes and plasma cells, multifocal gliosis and neuronal necrosis (Deng and others 2012). In cases of selenium poisoning, microscopical lesions are observed mainly in the cervical and lumbar intumescence of the spinal cord, specifically in the grey matter of the ventral horns, as focal symmetrical poliomyelomalacia (Nathues and others 2010).…”

Epidemiology and molecular characterization ofPorcine teschovirusin Hunan, China

“…There are at least 13 distinct serotypes of PTV, including novel serotypes that were recently identified (Boros et al., ; Cano‐Gómez & Jiménez‐Clavero, , ; Cano‐Gómez et al., ; Zell et al., ). In general, PTVs are non‐pathogenic, and infected swine are most often asymptomatic (Knowles, ); however, sporadic cases have been associated with a variety of clinical symptoms, including polioencephalomyelitis, female reproductive disorders, and enteric and respiratory disease (Deng et al., ; Dunne, Gobble, Hokanson, Kradel, & Bubash, ; Knowles, ; Lin, Cui, & Zell, ; Meyer, Woods, & Simon, ; Prodelalova, Malenovska, & Valicek, ; Zhang et al., ). Teschovirus encephalomyelitis, also known as Teschen or Talfan disease, was first reported in Teschen, Czechoslovakia in 1929 (Trefny, ).…”

“…Since then, the disease spreads throughout Europe and other continents during the 1940s and 1950s, causing devastating economic losses. At present, a mild form of the disease, with the exception of an outbreak in 2009 in the Republic of Haiti, has been described in many countries (Bangari, Pogranichniy, Gillespie, & Stevenson, ; Deng et al., ; Knowles, ; Pinto, Ankers, Werthmann, & Hamilton, ; Salles et al., ; Takahashi, Seimiya, Seki, & Yamada, ; Wang et al., ; Yamada et al., ; Zhang et al., ). The first documented PTV isolate (Swine/CH/IMH/03) in China was identified in 2003, and some cases and epidemiological studies related to PTV in China have been reported since then (Feng et al., ; Lin et al., ; Qiu, Wang, Zhang, Zhang, & Cui, ).…”