To investigate an outbreak of African horse sickness (AHS) on a horse farm in northeastern Thailand, we used whole-genome sequencing to detect and characterize the virus. The viruses belonged to ...serotype 1 and contained unique amino acids (95V,166S, 660I in virus capsid protein 2), suggesting a single virus introduction to Thailand.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, ODKLJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Influenza A virus causes respiratory disease in many animal species as well as in humans. Due to the high human-animal interface, the monitoring of canine influenza in dogs and the study of the ...transmission and pathogenicity of canine influenza in animals are important.
Eight-week-old beagle dogs (Canis lupus familaris) (n = 13) were used for the intraspecies transmission model. The dogs were inoculated intranasally with 1 ml of 10
EID
per ml of canine H3N2 influenza virus (A/canine/Thailand/CU-DC5299/2012) (CIV-H3N2). In addition, 4-week-old guinea pigs (Cavia porcellus) (n = 20) were used for the interspecies transmission model. The guinea pigs were inoculated intranasally with 300 µl of 10
EID
per ml of CIV-H3N2.
For the Thai CIV-H3N2 challenged in the dog model, the incoculated and direct contact dogs developed respiratory signs at 2 dpi. The dogs shed the virus in the respiratory tract at 1 dpi and developed an H3-specific antibody against the virus at 10 dpi. Lung congestion and histopathological changes in the lung were observed. For the Thai CIV-H3N2 challenge in the guinea pig model, the incoculated, direct contact and aerosol-exposed guinea pigs developed fever at 1-2 dpi. The guinea pigs shed virus in the respiratory tract at 2 dpi and developed an H3-specific antibody against the virus at 7 dpi. Mild histopathological changes in the lung were observed.
The result of this study demonstrated evidence of intraspecies and interspecies transmission of CIV-H3N2 in a mammalian model.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Influenza virus is not known to affect wild felids. We demonstrate that avian influenza A (H5N1) virus caused severe pneumonia in tigers and leopards that fed on infected poultry carcasses. This ...finding extends the host range of influenza virus and has implications for influenza virus epidemiology and wildlife conservation.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, ODKLJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The objectives of this study were to determine the survival of avian influenza virus (AIV) subtype H5N1 under various physical and chemical treatments, including disinfectants, temperature and pH. ...The highly pathogenic AIVs subtype H5N1 were isolated from internal organs of suspected chickens and were characterized by the inoculation into chicken embryonated eggs (CEEs), hemagglutination (HA) test, hemagglutination inhibition (HI) test, reverse transcriptase polymerase chain reaction (RT-PCR) and nucleotide sequencing of hemagglutinin (H) and neuraminidase (N) genes. Three H5N1 isolates, at the concentration of 109 50% embryo lethal dose (ELD50)/ml, were used for the determination of the survival of the virus under different chemical and physical treatments. The chemical treatments were performed by incubating the viruses with various types of disinfectants including glutaraldehyde (Glu), hydrogen peroxide, quaternary ammonium compounds (QAC), Glu+QAC, iodine, chlorine, formalin and phenol, at 25 and 37°C, for 0, 5, 7, and 14 days. The physical treatments included incubation of the viruses at 55, 60, 65, 70 and 75°C for 10, 15, 30, 45 and 60min or pH 3, 5, 7, 9 and 12. The results revealed that AIV H5N1 reference viruses, 2004.1, CUK-2/04 and 2004.2, showed low or no resistance against Glu+QAC, chlorine and phenol at both tested temperatures. Incubations at 70°C for 60min or at least 75°C for at least 45min could effectively inactivate all of the isolates, whereas all ranges of pH could not inactivate any of them. In this study, CUK-2/04 was more resistant to the disinfectants, temperatures, and pH compared to the other isolates.
Central nervous system (CNS) dysfunction caused by neurovirulent influenza viruses is a dreaded complication of infection, and may play a role in some neurodegenerative conditions, such as ...Parkinson-like diseases and encephalitis lethargica. Although CNS infection by highly pathogenic H5N1 virus has been demonstrated, it is unknown whether H5N1 infects neural progenitor cells, nor whether such infection plays a role in the neuroinflammation and neurodegeneration. To pursue this question, we infected human neural progenitor cells (hNPCs) differentiated from human embryonic stem cells in vitro with H5N1 virus, and studied the resulting cytopathology, cytokine expression, and genes involved in the differentiation. Human embryonic stem cells (BG01) were maintained and differentiated into the neural progenitors, and then infected by H5N1 virus (A/Chicken/Thailand/CUK2/04) at a multiplicity of infection of 1. At 6, 24, 48, and 72 hours post-infection (hpi), cytopathic effects were observed. Then cells were characterized by immunofluorescence and electron microscopy, supernatants quantified for virus titers, and sampled cells studied for candidate genes.The hNPCs were susceptible to H5N1 virus infection as determined by morphological observation and immunofluorescence. The infection was characterized by a significant up-regulation of TNF-α gene expression, while expressions of IFN-α2, IFN-β1, IFN-γ and IL-6 remained unchanged compared to mock-infected controls. Moreover, H5N1 infection did not appear to alter expression of neuronal and astrocytic markers of hNPCs, such as β-III tubulin and GFAP, respectively. The results indicate that hNPCs support H5N1 virus infection and may play a role in the neuroinflammation during acute viral encephalitis.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Lawsonia intracellularis is an obligate intracellular bacterium which cannot be cultured by conventional bacteriological methods. Furthermore, L. intracellularis needs enriched medium and a unique ...atmosphere for isolation, cultivation and propagation. Because of this,there are only a few isolates of L. intracellularis available and few studies in vitro demonstrating the susceptibility of this bacterium to antimicrobial agents. The objectives of this study were to isolate South American and Southeast Asia strains of L.intracellularis and to determine the in vitro antimicrobial activity against these isolates. Tested antimicrobials included: chlortetracycline, lincomycin, tiamulin, tylosin and valnemulin(against both Brazilian and Thailand strains) and additionally, amoxicillin, zinc-bacitracin, carbadox, enrofloxacin, gentamicin, sulfamethazine, trimethoprim, spectinomycin and a combination (1:1) of spectinomycin and lincomycin were also tested against the Thai isolates. The minimum inhibitory concentration (MIC) was determined by the antimicrobial activity that inhibited 99% of L. intracellularis growth in a cell culture as compared to the control (antimicrobial-free).
Two strains from Brazil and three strains from Thailand were successfully isolated and established in cell culture. Each antimicrobial was evaluated for intracellular and extracellular activity. Pleuromutilin group (valnemulin and tiamulin) and carbadox were the most active against L. intracellularis strains tested. Tylosin showed intermediate activity, chlortetracycline had variable results between low and intermediate activity, as well as spectinomycin, spectinomycin and lincomycin, amoxicillin, sulfamethazine and enrofloxacin. L. intracellularis was resistant to lincomycin, gentamicin, trimethoprim, colistin and bacitracin in in vitro conditions.
This is the first report of isolation of L. intracellularis strains from South America and Southeast Asia and characterization of the antimicrobial susceptibility patterns of these new strains.
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Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
During the second outbreak of avian influenza H5N1 in Thailand, probable horizontal transmission among tigers was demonstrated in the tiger zoo. Sequencing and phylogenetic analysis of those viruses ...showed no differences from the first isolate obtained in January 2004. This finding has implications for influenza virus epidemiology and pathogenicity in mammals.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, ODKLJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
A surveillance program for influenza A viruses (H5N1) was conducted in live bird and food markets in central Thailand during July 2006-August 2007. Twelve subtype H5N1 viruses were isolated. The ...subtype H5N1 viruses circulating in the markets were genetically related to those that circulated in Thailand during 2004-2005.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, ODKLJ, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
The present study investigated the seroprevalence of porcine reproductive and respiratory syndrome virus, Aujeszky’s disease virus (ADV), and porcine parvovirus (PPV) in replacement gilts from ...selected five swine herds in Thailand. The study consisted of three parts. First, a retrospective data analysis on the seroprevalence of porcine reproductive and respiratory syndrome virus (PRRSV) and ADV glycoprotein I (gI) in gilts, sows, boars, nursery, and fattening pigs in five herds (
n
= 7,030). Second, a cross-sectional study on seroprevalence of PRRSV, ADV, and PPV (
n
= 200) in replacement gilts. Last, the seroprevalence of PRRSV, ADV, and PPV in gilts culled due to reproductive failure (
n
= 166). Across the herds, the seroprevalence of PRRSV and ADV was 79.3% and 5.3%, respectively. The cross-sectional study revealed that 87.5%, 4.0%, and 99.0% of the replacement gilts were infected with PRRSV, ADV, and PPV, respectively. In the gilts culled due to reproductive failure, the seroprevalence of PRRSV, ADV, and PPV was 73.5%, 28.3%, and 86.0%, respectively. Of these culled gilts, 75.5% had been infected with at least two viruses and 18.9% had been infected with all three viruses. It could be concluded that most of the replacement gilts were exposed to PRRSV (84%), PPV (97%), and ADV (4%) before entering the breeding house. PPV was an enzootic disease among the selected herds. The prevalence of ADV was higher in gilts culled due to reproductive disturbance than in the healthy gilts.
Klebsiella pneumoniae
is a Gram-negative bacterium implicated as the causative pathogen in several medical health issues with different strains causing different pathologies including pneumonia, ...bloodstream infections, meningitis and infections from wounds or surgery. In this study, four captive African marmosets housed in Thailand were found dead. Necropsy and histology revealed congestion of hearts, kidneys and adrenal glands. Twenty-four bacterial isolates were obtained from these four animals with all isolates yielding identical phenotypes indicative of
K. pneumoniae
based on classical identification schema. All the isolates show the susceptibility to amikacin, cephalexin, doxycycline, gentamicin, and enrofloxacin with intermediate susceptibility to amoxycillin/clavulanic acid. One isolate (20P167W) was chosen for genome analysis and determined to belong to sequence type 65 (ST65). The genome of 20P167W possessed multiple virulence genes including
mrk
gene cluster and
iro
and
iuc
gene cluster (salmochelin and aerobactin, respectively) as well as multiple antibiotic resistance genes including
bla
SHV
−67
,
bla
SHV
−11
,
oqxA, oqxB
, and
fosA
genes resembling those found in human isolates; this isolate has a close genetic relationship with isolates from humans in Ireland, but not from Thailand and California sea lions. Phylogenetic studies using SNP show that there was no relation between genetic and geographic distributions of all known strains typing ST65, suggesting that ST65 strains may spread worldwide through multiple international transmission events rather than by local expansions in humans and/or animals. We also predict that
K. pneumoniae
ST65 has an ability to acquire genetic mobile element from other bacteria, which would allow Klebsiella to become an even greater public health concern.
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