Molecular investigation of feline coronavirus (FCoV) in local pet cats

Feline coronavirus (FCoV) infection is a very common in cat population. FCoV is further classified into two biotypes namely feline enteric coronavirus (FECV) and mutated feline infectious peritonitis virus (FIPV), in which FIPV causes a fatal immune complex disease by changing the tropism from enterocytes to monocytes. Previous studies on molecular detection of FCoV in cats were carried out in catteries but limited study investigate the presence of FCoV antigen in local pet cats. By considering this fact, this study aims to detect FCoV antigen via RT-PCR assay in local pet cats and to compare the similarity of the identified FCoV strain with previous related virus by phylogenetic analysis. By using convenience sampling, rectal swabs and buffy coat were collected from 16 clinically ill pet cats and 5 healthy pet cats. Viral RNA was extracted and subjected to one-step RT-PCR, targeting polymerase gene. Only one out of 21 fecal samples was positive for FCoV and none from buffy coat samples. Phylogenetic analysis revealed that the identified positive sample was highly homologous, up to 95%, to FCoV strain from Netherlands and South Korea on partial sequence of polymerase gene. In conclusion, this study detected FCoV antigen in local pet cats from fecal samples while negative detection from fecal and buffy coat samples could not completely rule out the possibilities of FCoV infection due to the complexity of the virus diagnosis that require multiple series of analysis

Detection of pinworms in conventionally maintained laboratory mice

The laboratory mice (Mus musculus) are commonly utilised for research purposes. Despite strict biosecurity, they potentially harbour parasites which may compromise the experimental study. Parasite intensity differs among strains of mice. This study aims to identify the presence of parasites between two strains of laboratory mice. A total of 48 mice (n= 48) obtained from the UPM Animal Resource Unit (ARU), consisting of 24 animals for each group of inbred strain Bagg Albino (BALB/c) and outbred Institute Cancer Research (ICR) mice were used for detection of helminths, ectoparasites and blood parasites. Based on parasitological distinct characteristics, Syphacia obvelata (S. obvelata) and Aspiculuris tetraptera (A. tetraptera) were detected. Both helminths were seen in 8.33% of BALB/c and 20.83% of ICR mice, respectively. Single infection by S. obvelata was detected in 33.33% of BALB/c mice while 12.5% of ICR mice were manifested merely by A. tetraptera. The findings revealed an optimal method to identify S. obvelata through perianal tape test while A. tetraptera is best detected by the faecal flotation technique. Statistically, the type of helminth was significantly associated with the strains of mice (P=0.043). Overall, there were low amounts of opportunistic helminths and ova with the absence of ectoparasites and blood parasites for both strains of laboratory mice which is suggestive of appropriate management practised

A case report of wet form Feline Infectious Peritonitis (FIP) in a domestic short hair cat

Feline Infectious Peritonitis (FIP), a fatal disease of cat exists in two major forms namely effusive and noneffusive form. FIP is caused by mutated form of Feline Coronavirus (FCoV) classified under the genus of Alphacoronavirus. Despite common prevalence of FIP in Malaysia, further diagnosis remain challenging due to the complexity of the disease which often required multiple findings to confirm the disease. This case report highlights the progressive wet form of FIP in a male domestic short hair cat named Cromox presented to the Post Mortem Unit, Faculty of Veterinary Medicine, Universiti Putra Malaysia (UPM). Manifestation of distended abdomen, icterus and flu was shown before the cat died. Post-mortem and histopathology analysis of affected organs were performed and since FIP was suspected, RT-PCR against polymerase gene of FCoV was carried out. The post mortem examination revealed generalised icterus at sclera, gums and integuments, straw colour peritoneal fluid and congestion of kidney and liver. Histopathology analysis showed infiltration of mononuclear cells in liver, pulmonary edema and renal desquamation. Meanwhile, RT-PCR and partial sequencing analysis showed evidence of positive Feline Coronavirus which was closely related to the FCoV from China and Netherland. Hence, the cause of death of Cromox was confirmed due to FIP infection. Only supportive treatment can be given to the FIP affected cat since the disease is usually fatal. Vaccination against FIP is not recommended and avoiding the sick cat to share litterbox in the multihousehold cat has been proven to be an effective way to prevent the occurence of FIP

Co-infections of Tilapia Lake Virus, Aeromonas hydrophila and Streptococcus agalactiae in farmed red hybrid tilapia

A high death rate among red hybrid tilapias was observed in a farm in Selangor, Malaysia, in January 2020. The affected fish appeared lethargic, isolated from schooling group, showed loss of appetite, red and haemorrhagic skin, exophthalmia and enlarged gall bladders. Histopathological assessment revealed deformation of kidney tubules, and severe congestion with infiltrations of inflammatory cells in the brains and kidneys. Syncytial cells and intracytoplasmic inclusion bodies were occasionally observed in the liver and brain sections. Tilapia Lake Virus (TiLV), Aeromonas hydrophila and Streptococcus agalactiae were identified in the affected fish, either through isolation or through PCR and sequencing analysis. The phylogenetic tree analysis revealed that the TiLV strain in this study was closely related to the previously reported Malaysian strain that was isolated in 2019. On the other hand, A. hydrophila and S. agalactiae were closer to Algerian and Brazilian strains, respectively. The multiple antibiotic resistance index for A. hydrophila and S. agalactiae was 0.50 and 0.25, respectively. Co-infections of virus and bacteria in cultured tilapia is a new threat for the tilapia industry

The distribution of important sero-complexes of flaviviruses in Malaysia

Flaviviruses (FVs) are arthropod-borne viruses of medical and veterinary importance. Numerous species of FVs have been isolated from various host; mainly humans, animals, ticks, and mosquitoes. Certain FVs are extremely host-specific; at the same time, some FVs can infect an extensive range of species. Based on published literatures, 11 species of FVs have been detected from diverse host species in Malaysia. In humans, dengue virus and Japanese encephalitis virus have been reported since 1901 and 1942. In animals, the Batu Cave virus, Sitiawan virus, Carey Island, Tembusu virus, Duck Tembusu virus, and Japanese encephalitis viruses were isolated from various species. In mosquitoes, Japanese encephalitis virus and Kunjin virus were isolated from Culex spp., while Zika virus and Jugra virus were isolated from Aedes spp. In ticks, the Langat virus was isolated from Ixodes spp. One of the major challenges in the diagnosis of FVs is the presence of sero-complexes as a result of cross-reactivity with one or more FV species. Subsequently, the distribution of specific FVs among humans and animals in a specific population is problematic to assess and often require comprehensive and thorough analyses. Molecular assays such as quantitative reverse transcriptase polymerase chain reaction (qRT-PCR) and digital droplet RT-PCR (ddRT-PCR) have been used for the differentiation of flavivirus infections to increase the accuracy of epidemiological data for disease surveillance, monitoring, and control. In situations where sero-complexes are common in FVs, even sensitive assays such as qRT-pCR can produce false positive results. In this write up, an overview of the various FV sero-complexes reported in Malaysia to date and the challenges faced in diagnosis of FV infections are presented

Japanese Encephalitis in Malaysia: an overview and timeline

Japanese encephalitis (JE) is a vector-borne zoonotic disease caused by the Japanese encephalitis virus (JEV). It causes encephalitis in human and horses, and may lead to reproductive failure in sows. The first human encephalitis case in Malaya (now Malaysia) was reported during World War II in a British prison in 1942. Later, encephalitis was observed among race horses in Singapore. In 1951, the first JEV was isolated from the brain of an encephalitis patient. The true storyline of JE exposure among humans and animals has not been documented in Malaysia. In some places such as Sarawak, JEV has been isolated from mosquitoes before an outbreak in 1992. JE is an epidemic in Malaysia except Sarawak. There are four major outbreaks reported in Pulau Langkawi (1974), Penang (1988), Perak and Negeri Sembilan (1998–1999), and Sarawak (1992). JE is considered endemic only in Sarawak. Initially, both adults and children were victims of JE in Malaysia, however, according to the current reports; JE infection is only lethal to children in Malaysia. This paper describes a timeline of JE cases (background of each case) from first detection to current status, vaccination programs against JE, diagnostic methods used in hospitals and factors which may contribute to the transmission of JE among humans and animals in Malaysia

Exposure to Zoonotic West Nile Virus in Long-Tailed Macaques and Bats in Peninsular Malaysia

The role of wildlife such as wild birds, macaques, and bats in the spreading and maintenance of deadly zoonotic pathogens in nature have been well documented in many parts of the world. One such pathogen is the mosquitoes borne virus, namely the West Nile Virus (WNV). Previous research has shown that 1:7 and 1:6 Malaysian wild birds are WNV antibody and RNA positive, respectively, and bats in North America may not be susceptible to the WNV infection. This study was conducted to determine the status of WNV in Malaysian macaques and bats found in mangrove forests and caves, respectively. Archive sera and oropharyngeal swabs from long-tailed macaques were subjected to the antibody detection using WNV competitive enzyme-linked immunosorbent assay (c-ELISA) and WNV RNA using RT-PCR, respectively, while the archive oropharyngeal and rectal swabs from bats were subjected to RT-PCR without serological analysis due to the unavailability of serum samples. The analysis revealed a WNV seropositivity of 29.63% (24/81) and none of the macaques were positive for WNV RNA. Meanwhile, 12.2% (5/41) of the bats from Pteropodidae, Emballonuridae, and Rhinolophidae families tested positive for WNV RNA. Here, we show a high WNV antibody prevalence in macaques and a moderate WNV RNA in various Malaysian bat species, suggesting that WNV circulates through Malaysian wild animals and Malaysian bat species may be susceptible to the WNV infectio

Differential modulation of immune response and cytokine profiles in the bursae and spleen of chickens infected with very virulent infectious bursal disease virus

Background: Very virulent infectious bursal disease virus (vvIBDV) induces immunosuppression and inflammation in young birds, which subsequently leads to high mortality. In addition, infectious bursal disease (IBD) is one of the leading causes of vaccine failure on farms. Therefore, understanding the immunopathogenesis of IBDV in both the spleen and the bursae could help effective vaccine development. However, previous studies only profiled the differential expression of a limited number of cytokines, in either the spleen or the bursae of Fabricius of IBDV-infected chickens. Thus, this study aims to evaluate the in vitro and in vivo immunoregulatory effects of vvIBDV infection on macrophage-like cells, spleen and bursae of Fabricius. Results: The viral load was increased during the progression of the in vitro infection in the HD11 macrophage cell line and in vivo, but no significant difference was observed between the spleen and the bursae tissue. vvIBDV infection induced the expression of pro-inflammatory and Th1 cytokines, and chemokines from HD11 cells in a time- and dosage-dependent manner. Furthermore, alterations in the lymphocyte populations, cytokine and chemokine expression, were observed in the vvIBDV-infected spleens and bursae. A drastic rise was detected in numbers of macrophages and pro-inflammatory cytokine expression in the spleen, as early as 2 days post-infection (dpi). On 4 dpi, macrophage and T lymphocyte infiltration, associated with the peak expression of pro-inflammatory cytokines in the bursae tissues of infected chickens were observed. The majority of the significantly regulated pro-inflammatory cytokines and chemokines, in vvIBDV-infected spleens and bursae, were also detected in vvIBDV-infected HD11 cells. This cellular infiltration subsequently resulted in a sharp rise in nitric oxide (NO) and lipid peroxidation levels. Conclusion: This study suggests that macrophage may play an important role in regulating the early expression of pro-inflammatory cytokines, first in the spleen and then in the bursae, the latter tissue undergoing macrophage infiltration at 4 dpi

Comparison of expression for IL-15 and IL-18 on dendritic cells and macrophages upon infection with recombinant fowlpox virus versus wild type fowlpox virus

Fowlpox is a viral disease of chicken caused by fowlpox virus (FWPV). Compared to other viral infectious diseases, studies on the interaction of antigen-presenting cells (APC) such as dendritic cells (DCs) and macrophage with FWPV remains limited. Therefore, this work was aimed to characterize cytokine responses upon infection of recombinant fowlpox viruses (rFWPV) expressing H5 gene of avian influenza virus (AIV) compared to wild type FWPV on chicken DCs and macrophage cells. Chicken bone marrow cells were first isolated. The cells were differentiated into DCs (GM-CSF and IL-4 acted as supplements in RPMI media), or into macrophages (no supplements added). In order to quantify chicken IL-15 and IL-18 cytokine expression, qPCR assays based on real-time analysis were performed. Data suggested that rFWPV induced higher expression for IL-15 and IL-18 on macrophage while wild type FWPV induced higher expression for IL-15 and IL-18 on DC