Occurrence of Chlamydia spp. in wild birds in Thailand

Objective: To determine the occurrence of Chlamydia spp. in wild birds in Thailand. Methods: Cloacal and tracheal swabs of 313 wild birds from 11 orders, 27 families, and 51 species were tested to determine the occurrence of Chlamydia infection. The outer membrane protein A (ompA) gene was amplified from positive samples to construct a phylogenetic tree. Results: At the time of sample collection, none of the birds showed clinical signs of any disease. Of 313 wild birds, two Asian openbill stork (Anastomus oscitans) were positive for Chlamydia spp., representing 0.64% (2/313) and 4.9% (2/41) occurrence for birds overall and for the Asian openbill stork, respectively. Phylogram analysis based on deduced amino acid of the ompA gene showed that Chlamydia spp. in Asian openbill storks was closely related to that in wildfowl (Pica pica and Cygnus olor) from Poland in a different branch with a 95% bootstrap value and had a shorter evolutionary distance to Chlamydia abortus. Conclusions: Asymptomatic Asian openbill storks could be a potential source of Chlamydia infection in domestic animals, poultry, and humans who share their habitat

Molecular study of feline hemoplasmas in freeranging fishing cats (Prionailurus viverrinus) in Thailand

Feline hemoplasmas, consisting of Mycoplasma haemofelis (M. haemofelis), Candidatus Mycoplasma haemominutum (Ca. M. haemominutum), and Candidatus Mycoplasma turicensis (Ca. M. turicensis), cause feline infectious anemia and zoonoses. Using multiplex PCR and phylogenetic analysis based on 16S rRNA, 22 blood samples from fishing cats (Prionailurus viverrinus) living in Khao Sam Roi Yot National Park, Thailand were determined positive for M. haemofelis (13.6%)and Ca. M. haemominutum (22.7%). M. haemofelis and Ca. M. haemominutum infection can result severe anemia and asymptomatic, respectively. However, not all positive cases exhibit anemia symptoms. Future study of hemoplasma infection in wild felids is necessary for conservation and the preservation of public health in Thailand

Serosurveillance for pandemic influenza A (H1N1) 2009 virus infection in domestic elephants, Thailand.

The present study conducted serosurveillance for the presence of antibody to pandemic influenza A (H1N1) 2009 virus (H1N1pdm virus) in archival serum samples collected between 2009 and 2013 from 317 domestic elephants living in 19 provinces situated in various parts of Thailand. To obtain the most accurate data, hemagglutination-inhibition (HI) assay was employed as the screening test; and sera with HI antibody titers ≥20 were further confirmed by other methods, including cytopathic effect/hemagglutination based-microneutralization (microNT) and Western blot (WB) assays using H1N1pdm matrix 1 (M1) or hemagglutinin (HA) recombinant protein as the test antigen. Conclusively, the appropriate assays using HI in conjunction with WB assays for HA antibody revealed an overall seropositive rate of 8.5% (27 of 317). The prevalence of antibody to H1N1pdm virus was 2% (4/172) in 2009, 32% (17/53) in 2010, 9% (2/22) in 2011, 12% (1/8) in 2012, and 5% (3/62) in 2013. Notably, these positive serum samples were collected from elephants living in 7 tourist provinces of Thailand. The highest seropositive rate was obtained from elephants in Phuket, a popular tourist beach city. Young elephants had higher seropositive rate than older elephants. The source of H1N1pdm viral infection in these elephants was not explored, but most likely came from close contact with the infected mahouts or from the infected tourists who engaged in activities such as elephant riding and feeding. Nevertheless, it could not be excluded that elephant-to-elephant transmission did occur

Binding efficiency of protein A/G-HRP to elephant serum Ig.

<p>(A) Under non-reducing conditions: protein A/G conjugate binds elephant IgG molecule at the MW of 150 kDa; (B) Under reducing conditions: protein A/G conjugate binds both H chain and L chain of elephant IgG with MW of 50 and 25 kDa, respectively (left panel). These MWs are identical to those of human IgG which reacts with HRP conjugated-goat anti-human IgG, IgM, IgA (H+L) and shows various bands of proteins with different MWs, suggesting of H chains and L chains of different Ig classes (right panel). The result also demonstrated that H chain, but not L chain of human Ig, binds protein A/G efficiently (middle panel).</p

Serological and Molecular Surveillance for SARS-CoV-2 Infection in Captive Tigers (<i>Panthera tigris</i>), Thailand

Coronavirus disease (COVID-19) is an emerging infectious disease caused by SARS-CoV-2. Given the emergence of SARS-CoV-2 variants, continuous surveillance of SARS-CoV-2 in animals is important. To monitor SARS-CoV-2 infection in wildlife in Thailand, we collected 62 blood samples and nine nasal- and rectal-swab samples from captive tigers (Panthera tigris) in Ratchaburi province in Thailand during 2020–2021. A plaque reduction neutralization test (PRNT) was employed to detect SARS-CoV-2 neutralizing antibodies. A real-time RT-PCR assay was performed to detect SARS-CoV-2 RNA. Our findings demonstrated that four captive tigers (6.5%, 4/62) had SARS-CoV-2 neutralizing antibodies against Wuhan Hu-1 and the Delta variant, while no SARS-CoV-2 RNA genome could be detected in all swab samples. Moreover, a low-level titer of neutralizing antibodies against the Omicron BA.2 subvariant could be found in only one seropositive tiger. The source of SARS-CoV-2 infection in these tigers most likely came from close contact with the infected animals’ caretakers who engaged in activities such as tiger petting and feeding. In summary, we described the first case of natural SARS-CoV-2 infection in captive tigers during the COVID-19 outbreak in Thailand and provided seroepidemiological-based evidence of human-to-animal transmission. Our findings highlight the need for continuous surveillance of COVID-19 among the captive tiger population and emphasize the need to adopt a One Health approach for preventing and controlling outbreaks of COVID-19 zoonotic disease