In 2006, the annual number of Koreans traveling internationally increased to 11 million. With this increased number of Koreans traveling to developing countries, various infectious diseases have been reported to be imported into Korea. Immunization is an important tool for the prevention of such diseases. Vaccination offered to international travelers is divided into 3 categories, i.e., obligatory vaccination, vaccines against diseases with an increased risk in developing countries, and routine vaccination. Vaccination that is obligatory for travelers includes yellow fever vaccine for travelers entering yellow fever-endemic areas and meningococcal vaccination for pilgrims traveling to Saudi Arabia. Recent reports of the adverse event following yellow fever vaccination, i.e., vaccine-associated viscerotropic disease, pose a caution in the administration of yellow fever vaccine to the elderly or individuals with thymic diseases. Protein-conjugated meningococcal vaccines are generally preferred; however, polysaccharide vaccines are also effective in short-term travelers. The vaccinations recommended for the health of travelers include administration of hepatitis A (HAV), meningococcal, typhoid, rabies, tick-borne encephalitis, and plague vaccines. As many young Korean adults lack immunity against hepatitis A, the administration of the HAV vaccine is recommended for all Korean individuals in their 20s and all Korean seronegative individuals in their 30s. The risk of acquiring typhoid fever is high among travelers traveling to the rural areas of developing countries for 2 weeks or more. The rabies vaccine may be recommended for travelers traveling for longer than 3 months and animal handlers. Both tick-borne encephalitis and plague are rarely encountered among Korean travelers; furthermore, vaccines for these diseases are not available in Korea. As Japanese encephalitis is endemic in Korea, vaccination against encephalitis is not essential for Korean adults. Pre-travel counseling is an important opportunity for catch-up vaccination of healthy travelers who missed routine vaccinations.
Adult ; Aged ; Animals ; Communicable Diseases ; Counseling ; Developing Countries ; Encephalitis ; Encephalitis, Japanese ; Encephalitis, Tick-Borne ; Hepatitis A ; Humans ; Immunization ; Korea ; Meningococcal Vaccines ; Plague ; Rabies ; Rabies Vaccines ; Saudi Arabia ; Typhoid Fever ; Vaccination ; Vaccines ; Whooping Cough ; Yellow Fever ; Yellow Fever Vaccine

OBJECTIVETo develop a rapid, cost effective RT-PCR method for the mass scale diagnosis of such diseases at the viremia stage to find out the actual disease burden in that area.

METHODSFor this purpose, cases with the history of only short febrile illness were considered. Thus 157 samples with the history of dengue/chikungunya like illness and only 58 samples with a history of acute encephalitis syndrome (AES) were selected.

RESULTSOut of 157 samples, 42 and 74 were detected as dengue and chikungunya, respectively and out of 58 AES cases only 23 could be detected as Japanese encephalitis by this RT-PCR method.

CONCLUSIONSThis cost effective RT-PCR method can detect the total positive cases that remain undetected by ELISA method. Moreover, this method is capable to detect the viral RNA from patients' sera even after the appearance of IgM antibody at one fifth costs as compared with the other commercially available kits.

Antibodies, Viral ; blood ; Arbovirus Infections ; diagnosis ; virology ; Arboviruses ; genetics ; Chikungunya Fever ; diagnosis ; virology ; Dengue ; diagnosis ; virology ; Encephalitis Virus, Japanese ; genetics ; Encephalitis, Japanese ; diagnosis ; virology ; Fever ; diagnosis ; virology ; Humans ; Immunoglobulin M ; blood ; Mass Screening ; RNA, Viral ; blood ; Reverse Transcriptase Polymerase Chain Reaction ; economics ; methods ; Sensitivity and Specificity ; Viremia ; diagnosis ; virology

Venezuelan equine encephalitis (VEE) is a zoonotic disease caused by the Venezuelan equine encephalitis virus (VEEV) complex. This disease has not yet been reported in China, and it is therefore essential to establish a rapid and accurate method for detection of the virus in order to prevent and control this disease. In this study, a one-step real-time quantitative RT-PCR method was developed for the detection of the VEEV complex. A pair of specific primers and a Taqman probe were designed corresponding to a conserved region of the VEEV gene nspl, allowing the detection of all known strains of different sub- types of the virus. Using RNA synthesized by in vitro transcription as template, the sensitivity of this method was measured at 3.27 x 10(2) copies/microL. No signal was generated in response to RNA from Chikungunya virus (CHIKV), nor to RNA encoding the nsp1 fragment of Eastern equine encephalitis virus (EE-EV) or Western equine encephalitis virus (WEEV), all of which belong to the same genus as VEEV. This indicates that the method has excellent specificity. These results show that this one-step real-time quantitative RT-PCR method may provide an effective tool for the detection of VEEV in China.
China ; DNA Primers ; genetics ; Encephalitis Virus, Venezuelan Equine ; classification ; genetics ; isolation & purification ; Encephalomyelitis, Venezuelan Equine ; virology ; Humans ; RNA, Viral ; genetics ; Reverse Transcriptase Polymerase Chain Reaction ; methods

Zika virus was first isolated in from nonhuman primate in 1947. It is in the genus Flavivirus, closely related to other flavivirus like Dengue, West Nile, Yellow fever and Japanese encephalitis virus. Since 2007 epidemic in Yap island, zika virus infections had spread to the countries in Micronesia and South Pacific. In 2015, Zika virus outbreak occurred in Brazil and now more than 40 countries in American continents reported autochthonous infection. The virus is transmitted mainly by Ae. aegypti mosquito with many other Aedes mosquito species known as vector. Recently, Zika virus infection is known to cause severe neurological complications and congenital malformation. In this paper, we will review current knowledge on Zika virus history, biology, clinical characteristics and preventive method.
Aedes ; Biology ; Brazil ; Culicidae ; Dengue ; Encephalitis Virus, Japanese ; Flavivirus ; Methods ; Microcephaly ; Micronesia ; Primates ; Yellow Fever ; Zika Virus Infection* ; Zika Virus*

There were 714 cases of dengue haemorrhagic fever and 1 death. The age of patients from 2-10 years old, none of them over 15 years old. The morbidity of III, IV degrees concentrated in Hon Dat, Tan Hiep, An Ninh, Rach Gia and also the districts that had the greatest morbidity, 56 cases of shock. The Steering Board issued a number of guideline documents and established preventive plan right at the beginning of the year with medical speciality. There were 28 cases of Japanese encephalitis, 25 cases with the age from 13 months - 5 years old, 3 cases with the age from 6-11 years old, 64% male and 36% female. The Pasteurs Institute of Ho Chi Minh City coordinated with the local authority to control the disease transmission in order to isolate virus and propagate measures of mosquito killing and hygienic methods around living area.
Dengue ; Encephalitis ; Encephalitis, Japanese

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

Three dimensional structures of envelope protein from Korean isolates and Nakayama-NIH strain of Japanese encephalitis virus (JEV) were deduced by a computer program (HyperChem 4.0 Chemplus 1.0) based on the data of the three dimentional structure of Tick-borne encephalitis virus. In the three dimensional structure of envelope protein, neutralizing epitope and T-helper cell recognition site of C-terminal region of Korean isolates were structually similar to those of Nakayama-NIH but the N-terminal region was not. Korean JE isolates were compared with Nakayama-NIH strain by using cross-neutralization antibody test. Neutralizing activities of Korean isolates derived from guinea pigs were higher than those of Nakayama-NIH strain against Korean isolates, although the polyclonal antibody titers of Nakayama-NIH showed 1:160 to 1:640 against Korean isolates. According to the results from three dimentional structures and cross-neutralization analyses, the antigenic difference between Korean JE isolates and Nakayama-NIH strain may be dependent on structural difference of envelope protein.
Animals ; Encephalitis Virus, Japanese ; Encephalitis Viruses* ; Encephalitis Viruses, Tick-Borne ; Encephalitis* ; Guinea Pigs ; Korea*

Zika virus (ZIKV) is an arthropod-borne member of the genus Flavivirus, closely related to the dengue, West Nile, Japanese encephalitis, and yellow fever viruses and is transmitted by Aedes spp. mosquitoes. It has emerged explosively since 2007 to cause a series of epidemics in Micronesia, the South Pacific, and most recently the Americas. Following the first detection of ZIKV on the American continent, autochthonous ZIKV transmission has been confirmed throughout Central and South America. The unprecedented numbers of people infected during recent outbreaks in the South Pacific and the Americas may have resulted in enough ZIKV infections to notice patterns of the associated incidence of congenital microcephaly, Gillain-Barre symdrome, and acute diffuse encephalomyelitis. Here we review the history, emergence, biology, transmission, and control strategies for the ongoing outbreak through vector-centric approaches on ZIKV to date.
Aedes ; Americas ; Arboviruses ; Biology ; Culicidae ; Dengue ; Disease Outbreaks ; Encephalitis, Japanese ; Encephalomyelitis ; Flavivirus ; Incidence ; Microcephaly ; Micronesia ; South America ; Yellow fever virus ; Zika Virus*

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

Analyzing HI tests of 110 cases of clinical Japanese Encephalitis in 1982, the following results are obtained. 1. The results of HI test are positive in 39 (35.5%), borderline positive in 19 (9.1%), negative in 14 (12.7%) and undetermined in 47 (43.7%) cases. 2. In 49 cases of positive HI test, 14 cases reveal the positive result on the first HI test requested in 5-27 days after the clinical onset of symptoms, and 35 cases show increasing HI titers on the follow-up studies. There is a tendency of increasing HI titers upto 3-4 weeks of onset and sustaining the value for more than two months. 3. In 35 cases with increasing titers on follow-up study, the highest titer is 1:80 in 5 cases, and the half of HI negative cases maintain that value throughout the course. 4. There is no significant statistical differences in clinical characteristics, laboratory and cerebrospinal fluid studies between the patient group of HI positive or borderline and group of HI negative or undermined, except mean hospital day and incidence of coma and death.
Cerebrospinal Fluid ; Coma ; Encephalitis, Arbovirus* ; Encephalitis, Japanese ; Follow-Up Studies ; Hemagglutination Inhibition Tests* ; Hemagglutination* ; Humans ; Incidence ; Korea*