In this review, we mainly focus on zoonotic encephalitides caused by arthropod-borne viruses (arboviruses) of the families Flaviviridae (genus Flavivirus) and Togaviridae (genus Alphavirus) that are important in both humans and domestic animals. Specifically, we will focus on alphaviruses (Eastern equine encephalitis virus, Western equine encephalitis virus, Venezuelan equine encephalitis virus) and flaviviruses (Japanese encephalitis virus and West Nile virus). Most of these viruses were originally found in tropical regions such as Africa and South America or in some regions in Asia. However, they have dispersed widely and currently cause diseases around the world. Global warming, increasing urbanization and population size in tropical regions, faster transportation and rapid spread of arthropod vectors contribute in continuous spreading of arboviruses into new geographic areas causing reemerging or resurging diseases. Most of the reemerging arboviruses also have emerged as zoonotic disease agents and created major public health issues and disease epidemics.
Africa ; Alphavirus* ; Animals, Domestic ; Arboviruses* ; Arthropod Vectors ; Asia ; Encephalitis ; Encephalitis Virus, Venezuelan Equine ; Encephalitis Virus, Western Equine ; Encephalitis Viruses ; Encephalomyelitis, Equine ; Epidemiology* ; Flaviviridae ; Flavivirus* ; Global Warming ; Humans ; Population Density ; Public Health ; South America ; Togaviridae ; Transportation ; Urbanization ; Zoonoses

Getah virus (GETV) is a member of the genus Alphavirus in the family Togaviridae. GETV infection can occur in a wide range of vertebrate species, and the virus has been known for a pathogen of horses and pigs. To rapidly and accurately diagnose GETV infection of a racehorse, an indirect ELISA (I-ELISA) was developed in the present study for detection of antibodies to GETV in serum samples. To evaluate the developed I-ELISA, a total of 240 serum samples from Thoroughbred racehorses raised in Korea were screened in parallel by a serum neutralization (SN) test. The developed I-ELISA exhibited an efficacy comparable to that of the SN test in terms of a high diagnostic sensitivity (86.3%) and specificity (94.5%) at a cut-off absorbance value of 0.25. In addition, our results showed that the developed I-ELISA had a significant correlation with the SN test (r = 0.91; p < 0.05). Taken together, our findings suggest that the I-ELISA developed in this study is a valuable diagnostic tool for the screening of horses suspected to be infected with GETV.
Alphavirus* ; Antibodies* ; Enzyme-Linked Immunosorbent Assay* ; Horses* ; Humans ; Korea ; Mass Screening ; Sensitivity and Specificity ; Swine ; Togaviridae ; Vertebrates

BACKGROUND: Chikungunya virus (CHIKV) is a mosquito- borne  alphavirus  of  the  family  Togaviridae  transmitted  to humans by the Aedes spp. mosquitoes, causing Chikungunya   Fever  (CHIKF).
OBJECTIVE: This study aims to describe the course and outcome of musculoskeletal (MSK) manifestations in patients  with  CHIKF  seen  over  a   three-month     period.
DESIGN: This is a prospective descriptive  study.  Seventy  patients  with  fever,  rash,  and  arthritis  seen   at the University of the Philippines-Philippine General Hospital  and  private  arthritis  clinics  were  collected from August - December 2012.  Demographics  and course   of   arthritis   were  described.
RESULTS:  Seventy   patients,   53   (68.6%)   female,   with  a mean age  of  39.2  ±13.50  were  diagnosed  with CHIKF. All cases were from the Metropolitan  Manila area. Of these, 15 (21.4%) had  family  members  affected. Twenty-four patients (34.3%) were either employed or students. The most common presenting symptoms were fever (94.3%), arthritis or athralgia  (98.6%), and rash (87.1%).  The  most  common  joint  areas involved were the ankles  (60.0%),  the  wrists (40.0%) and the small joints of the hand (51.4%). Twenty-seven (47.3%) had symmetric  arthritis.  Thirty- seven   cases   (52.9%)   had   arthralgia   or   arthritis    for at least  six  weeks.  By  the  end  of  the  follow-up  period, only four (5.7%) had persistent musculoskeletal symptoms. Age and  sex  were not  found to  be  factors in  determining  chronicity  of  arthritic  symptoms  (p   =   0.104   and   p=0.58  respectively). Of the seventy patients, 31 (44. 3%) were confirmed  cases  of  CHIKF--  29 had  (+)   CHIKV  IgM   by ELISA,  and  two   had   (+)   CHIKV   PCR.   Twenty-  one (67.7%) had  persistent  arthritis  of  at least  six  weeks. Treatment  consisted  of continuous  NSAIDs  for  at  least  two   weeks   and   some   received   steroids.  In this subgroup, age and sex were not shown to  correlate with chronic arthritis (p=0.47 and p=0.05 respectively).
CONCLUSION: This report on a recent outbreak of CHIKF showed the classic triad of fever, rash,  and  arthritis.  There  was  no  correlation  between  age  and  chronicity of  arthritic  symptoms.  Sex,  likewise,  did  not  appear   to influence chronicity. The disease occurred in family clusters. Patients required continuous treatment with NSAIDs and  some  had  to  be given  steroids.  Most cases   resolved   by   12 weeks.

Human ; Male ; Female ; Middle Aged ; Adult ; Chikungunya Fever ; Chikungunya Virus ; Togaviridae ; Anti-inflammatory Agents, Non-steroidal ; Arthralgia ; Arthritis ; Exanthema ; Enzyme-linked Immunosorbent Assay

Alphavirus Infections ; epidemiology ; Chikungunya virus ; Humans

Alphavirus Infections ; diagnosis ; epidemiology ; virology ; Animals ; Chikungunya Fever ; Chikungunya virus ; genetics ; isolation & purification ; physiology ; Humans ; Viral Proteins ; genetics ; metabolism

The incidence of chikungunya infection in Singapore has been on the rise since the first reported case in 2006. Acute polyarthritis, a common manifestation among affected patients, may precede fever and present with debilitating arthritis to rheumatologists, orthopaedists, internists and primary care physicians. The diagnosis of chikungunya infection requires careful history taking and a high index of suspicion, with supporting evidence from the reverse transcription-polymerase chain reaction or the chikungunya IgM serology test. Treatment of chikungunya arthritis usually involves non-steroidal anti-inflammatory drugs. Rarely, polyarthritis in chikungunya may persist even after resolution of the acute infection, necessitating treatment with disease-modifying anti-rheumatic drugs. In this article, we present the different manifestations of chikungunya arthritis in our local setting and review the literature.
Aged ; Alphavirus Infections ; complications ; Anti-Inflammatory Agents, Non-Steroidal ; therapeutic use ; Arthritis ; drug therapy ; virology ; Chikungunya Fever ; Chikungunya virus ; Female ; Humans ; Male ; Middle Aged

Various new technologies have been applied for developing vaccines against various animal diseases. Virus-like particle (VLP) vaccine technology was used for manufacturing the porcine circovirus type 2 and RNA particle vaccines based on an alphavirus vector for porcine epidemic diarrhea (PED). Although VLP is classified as a killed-virus vaccine, because its structure is similar to the original virus, it can induce long-term and cell-mediated immunity. The RNA particle vaccine used a Venezuela equine encephalitis (VEE) virus gene as a vector. The VEE virus partial gene can be substituted with the PED virus spike gene. Recombinant vaccines can be produced by substitution of the target gene in the VEE vector. Both of these new vaccine technologies made it possible to control the infectious disease efficiently in a relatively short time.
Alphavirus ; Animal Diseases ; Animals* ; Circovirus ; Communicable Diseases ; Diarrhea ; Encephalitis Virus, Venezuelan Equine ; Encephalomyelitis, Equine ; Immunity, Cellular ; Porcine epidemic diarrhea virus ; RNA ; Vaccines ; Vaccines, Synthetic ; Vaccines, Virus-Like Particle ; Venezuela

Objective To prepare mouse monoclonal antibodies against the ectodomain of E2 (E2ecto) glycoprotein of Western equine encephalitis virus (WEEV). Methods A prokaryotic expression plasmid pET-28a-WEEV E2ecto was constructed and transformed into BL21 (DE3) competent cells. E2ecto protein was expressed by IPTG induction and presented mainly as inclusion bodies. Then the purified E2ecto protein was prepared by denaturation, renaturation and ultrafiltration. BALB/c mice were immunized with the formulated E2ecto protein using QuickAntibody-Mouse5W as an adjuvant via intramuscular route, boosted once at an interval of 21 days. At 35 days post-immunization, mice with antibody titer above 1×10⁴ were inoculated with E2ecto intraperitoneally, and spleen cells were fused with SP2/0 cells three days later. Hybridoma cells secreting specific monoclonal antibodies were screened by the limited dilution method, and ascites were prepared after intraperitoneal inoculation of hybridoma cells. The subtypes and titers of the antibodies in ascites were assayed by ELISA. The biological activity of the mAb was identified by immunofluorescence assay(IFA) on BHK-21 cells which were transfected with eukaryotic expression plasmid pCAGGS-WEEV-CE3E2E1. The specificity of the antibodies were evaluated with E2ecto proteins from EEEV and VEEV. Results Purified WEEV E2ecto protein was successfully expressed and obtained. Four monoclonal antibodies, 3G6G10, 3D7G2, 3B9E8 and 3D5B7, were prepared, and their subtypes were IgG2c(κ), IgM(κ), IgM(κ) and IgG1(κ), respectively. The titers of ascites antibodies 3G6G10, 3B9E8 and 3D7G2 were 10⁵, and 3D5B7 reached 10⁷. None of the four antibody strains cross-reacted with other encephalitis alphavirus such as VEEV and EEEV. Conclusion Four strains of mouse mAb specifically binding WEEV E2ecto are successfully prepared.
Horses ; Animals ; Mice ; Encephalitis Virus, Western Equine ; Ascites ; Immunosuppressive Agents ; Antibodies, Monoclonal ; Immunoglobulin M

No abstract available.
Glycoproteins* ; Oligodendroglia* ; Rubella virus* ; Rubella*

PURPOSE: Chikungunya virus (CHIKV) causes endemic or epidemic outbreaks of CHIKV fever, which is a mosquitoe-transmitted viral disease in Africa, India, South-East Asia, and recently Southern Europe. Currently, serological diagnostic tests such as hemagglutination inhibition test (HI test), in-house IgM capture enzyme-linked immunosorbent assays (ELISA), and indirect immunofluorescence test were used for diagnosis of chikungunya fever, which are based on whole virus antigens. MATERIALS AND METHODS: CHIKV E1, and E2 envelope proteins for the CHIKV-specific serodiagnostic reagents for chikungunya fever were expressed in baculovirus expression system. The seroreactivity of recombinant CHIKV E1 and E2 envelope proteins were evaluated using sera panels of patients from Laboratoire Marcel Merieux by indirect IgM capture ELISA. RESULTS: The recombinant CHIKV E1 and E2 envelope protein showed sensitivity of 77.5% and 90%, respectively. The specificities of both CHIKV E1 and E2 envelope proteins were 100%. CONCLUSION: The recombinant CHIKV E1 and E2 envelope proteins could be a useful diagnostic reagent for CHIKV infection.
Alphavirus Infections/*diagnosis ; Animals ; Baculoviridae/genetics/metabolism ; Cells, Cultured ; Chikungunya virus/genetics ; Cloning, Molecular ; Enzyme-Linked Immunosorbent Assay/methods ; Recombinant Proteins/immunology ; Sensitivity and Specificity ; Serologic Tests/*methods ; Viral Envelope Proteins/*immunology