Latiffah Hassan

Characterization of Nipah Virus from Naturally Infected Pteropus vampyrus Bats, Malaysia

We isolated and characterized Nipah virus (NiV) from Pteropus vampyrus bats, the putative reservoir for the 1998 outbreak in Malaysia, and provide evidence of viral recrudescence. This isolate is monophyletic with previous NiVs in combined analysis, and the nucleocapsid gene phylogeny suggests that similar strains of NiV are co-circulating in sympatric reservoir species.

Evidence for Nipah virus recrudescence and serological patterns of captive Pteropus vampyrus

This study aimed to describe the transmission dynamics, the serological and virus excretion patterns of Nipah virus (NiV) in Pteropus vampyrus bats. Bats in captivity were sampled every 7-21 days over a 1-year period. The data revealed five NiV serological patterns categorized as high and low positives, waning, decreasing and increasing, and negative in these individuals. The findings strongly suggest that NiV circulates in wild bat populations and that antibody could be maintained for long periods. The study also found that pup and juvenile bats from seropositive dams tested seropositive, indicating that maternal antibodies against NiV are transmitted passively, and in this study population may last up to 14 months. NiV was isolated from the urine of one bat, and within a few weeks, two other seronegative bats seroconverted. Based on the temporal cluster of seroconversion, we strongly believe that the NiV isolated was recrudesced and then transmitted horizontally between bats during the study period.

Risk Factors for Nipah Virus Infection among Pteropid Bats, Peninsular Malaysia

Infection rates may be higher during pregnancy and lactation.

Prevalence and risk factors of feline leukaemia virus and feline immunodeficiency virus in peninsular Malaysia

BackgroundFeline leukaemia virus (FeLV) and feline immunodeficiency virus (FIV) are major causes of morbidity and mortality in domestic and wild felids. Despite the clinical importance of feline retroviruses and the growing interest in cats as pets, information about FeLV and FIV in Malaysia is presently insufficient to properly advise veterinarians and pet owners. A cross-sectional study was carried out from January 2010 to December 2010 to determine the prevalence and risk factors associated with FeLV and FIV among domestic cats in peninsular Malaysia. Plasma samples were harvested from the blood of 368 domestic cats and screened for evidence of FeLV p27 antigen and FIV antibodies, using an immunochromatographic kit. Additionally, data on cat demographics and health were collected using a structured questionnaire, and were evaluated as potential risk factors for FeLV or FIV status.ResultsOf the 368 cats that were evaluated in this study, 12.2% (45/368; 95% CI = 8.88 - 15.58) were positive for FeLV p27 antigen, 31.3%, (115/368; 95% CI = 26.51 - 35.99) were seropositive to FIV antibodies, and 4.3% (16/368; 95% CI = 2.27 - 6.43) had evidence of both viruses. Factors found to significantly increase the risk for FeLV seropositivity include sex, age, behaviour, sickness, and living in a multi-cat household. Seropositive response to FIV was significantly associated with sex, neuter status, age, behaviour, and health status.ConclusionsThe present study indicates that FeLV and FIV are common among domestic cats in peninsular Malaysia, and that factors related to cat demographics and health such as age, sex, behaviour, health status and type of household are important predictors for seropositive status to FeLV or FIV in peninsular Malaysia. High prevalence of FeLV or FIV observed in our study is of concern, in view of the immunosuppressive potentials of the two pathogens. Specific measures for control and prevention such as screening and routine vaccination are needed to ensure that FeLV and FIV are controlled in the cat population of peninsular Malaysia.

Genetic Variability of Vancomycin-Resistant Enterococcus faecium and Enterococcus faecalis Isolates from Humans, Chickens, and Pigs in Malaysia

ABSTRACT Vancomycin-resistant enterococci (VRE) have been reported to be present in humans, chickens, and pigs in Malaysia. In the present study, representative samples of VRE isolated from these populations were examined for similarities and differences by using the multilocus sequence typing (MLST) method. Housekeeping genes of Enterococcus faecium (n = 14) and Enterococcus faecalis (n = 11) isolates were sequenced and analyzed using the MLST databases eBURST and goeBURST. We found five sequence types (STs) of E. faecium and six STs of E. faecalis existing in Malaysia. Enterococcus faecium isolates belonging to ST203, ST17, ST55, ST79, and ST29 were identified, and E. faecium ST203 was the most common among humans. The MLST profiles of E. faecium from humans in this study were similar to the globally reported nosocomial-related strain lineage belonging to clonal complex 17 (CC17). Isolates from chickens and pigs have few similarities to those from humans, except for one isolate from a chicken, which was identified as ST203. E. faecalis isolates were more diverse and were identified as ST4, ST6, ST87, ST108, ST274, and ST244, which were grouped as specific to the three hosts. E. faecalis, belonging to the high-risk CC2 and CC87, were detected among isolates from humans. In conclusion, even though one isolate from a chicken was found clonal to that of humans, the MLST analysis of E. faecium and E. faecalis supports the findings of others who suggest VRE to be predominantly host specific and that clinically important strains are found mainly among humans. The infrequent detection of a human VRE clone in a chicken may in fact suggest a reverse transmission of VRE from humans to animals.

Tuberculosis in captive Asian elephants ( Elephas maximus ) in Peninsular Malaysia

A cross-sectional study was conducted from 10 January to 9 April 2012, to determine the seroprevalence of tuberculosis (TB) of all captive Asian elephants and their handlers in six locations in Peninsular Malaysia. In addition, trunk-wash samples were examined for tubercle bacillus by culture and polymerase chain reaction (PCR). For 63 elephants and 149 elephant handlers, TB seroprevalence was estimated at 20.4% and 24.8%, respectively. From 151 trunkwash samples, 24 acid-fast isolates were obtained, 23 of which were identified by hsp65-based sequencing as non-tuberculous mycobacteria. The Mycobacterium tuberculosis-specific PCR was positive in the trunk-wash samples from three elephants which were also seropositive. Conversely, the trunk wash from seven seropositive elephants were PCR negative. Hence, there was evidence of active and latent TB in the elephants and the high seroprevalence in the elephants and their handlers suggests frequent, close contact, two-way transmission between animals and humans within confined workplaces.

Bovine brucellosis trends in Malaysia between 2000 and 2008

BackgroundBovine brucellosis is an important disease affecting cattle characterised by abortion, still birth, reduced milk production, weak foetus and infertility in both males and females. There is wide distribution of the disease among cattle and several wildlife species. Bovine brucellosis is commonly caused by B. abortus and very occasionally B. melitensis and B. suis. The distribution of bovine brucellosis in cattle has not been described in Malaysia. In this paper we describe the distribution, pattern and trend of bovine brucellosis in Peninsular Malaysia between 2000 and 2008 based on serological data obtained from nationwide B. abortus serosurveillance activities in cattle populations.ResultsBrucella antibodies were detected in 21.8% of sampled herds (95% CI, 21.01–22.59) and 2.5% (95% CI; 2.45–2.55) of sampled cattle. The state of Pahang had the highest animal and herd-level seroprevalence of 5.3 and 43.6%, respectively. The herd-level seroprevalence varied but remained high (18-26%) over the period of study and generally increased from 2000 to 2008. Seropositive herds clustered around the central part of the peninsula within the period of the study. The months of September, October and November illustrated the highest rates with corresponding seroprevalences of 33.2, 38.4 and 33.9%, respectively. A noticeable variation was observed in the cattle-level seroprevalence, but the rate remained relatively low (<5%). The chi-square statistics showed herd size (χ2 = 1206.077, df = 2, p = 0.001), breed (χ2 = 37.429, df = 1, p = 0.001), month of sampling (χ2 = 51.596, df = 11 p = 0.001), year (χ2 = 40.08, df = 8, p = 0.001) and state (χ2 = 541.038, df = 10, p = 0.001) to be associated with increased seropositivity.ConclusionBovine brucellosis is widespread among herds in Peninsular Malaysia at a low within-herd seroprevalence rate.

Outbreaks of trypanosomiasis and the seroprevalence of T. evansi in a deer breeding centre in Perak, Malaysia

Trypanosoma evansi causes the disease called trypanosomiasis or “surra” in many species of both domestic and wild animals (Luckins and Dwinger 2004). The protozoa are transmitted mechanically by biting flies such as Tabanus and Stomoxys spp. (Luckins 1988). Trypanosomiasis generally causes anaemia, progressive emaciation and weakness in affected animals. In Malaysia, trypanosomiasis has been reported in institutional farms of cattle and buffaloes (Abas-Mazni and Zainal-Abidin 1985; Cheah et al. 1999) and in a rhinocerous centre (Vellayan et al. 2004). The disease is considered endemic in Southeast Asia, and has been reported in Thailand (Lohr et al. 1985), Indonesia (Payne et al. 1991) and Vietnam (Pham Si Lang 1991). Deer are susceptible to T. evansi, however, reports of trypanosomiasis in deer is not common. Within the region of Asia, only Gu et al., and Chen et al., as cited by Lun et al. (1993) have reported the occurrence of trypanosomiasis in deer in several provinces in China. In Malaysia, deer farming is gaining popularity due to its potential to cater for the meat market and for agrobased tourism and industry. Therefore, any diseases such as trypanosomiasis that result in large numbers of deaths of deer should strategically be controlled or prevented. In 2006, a large deer breeding centre in Lenggong in the state of Perak suffered an episode of deaths of the Cervus timorensis russa that was later confirmed as due to trypanosome (Nurulaini et al. 2007). Within a span of one week in March 2006, the deaths of 17 adult female deer between the ages of 12–13 years were recorded. During that period, 8 out of 28 blood samples submitted to the Veterinary Research Institute (VRI) in Ipoh, Perak were found positive for T. evansi. The present study was conducted to examine the trypanosomiasis outbreaks, and to determine the prevalence of trypanosomes among the deer population since the first outbreak in 2006.

The prevalence and distribution of Brucella melitensis in goats in Malaysia from 2000 to 2009

A study was conducted to describe the prevalence and distribution of zoonotic Brucella melitensis in goats in Peninsular Malaysia. Using serosurveillance data of the last decade (2000-2009) involving 119,799 goats and 3555 farms, the seroprevalence of brucellosis among goats was 0.91% (95% CI=0.86-0.96) and among farms was 7.09% (95% CI=6.27-7.98). The odds of brucellosis was significantly (P<0.05) higher in the later part of the decade, in larger herd size and among the states located in the peninsula as compared to eastern Malaysia. The infection was detected throughout Malaysia but at generally low seroprevalences with states like Perlis that border neighbouring countries having higher seroprevalence of brucellosis than other non-border states.

Molecular Relatedness of Methicillin-Resistant S. aureus Isolates from Staff, Environment and Pets at University Veterinary Hospital in Malaysia

Methicillin-resistant Staphylococcus aureus (MRSA) has emerged as a problem in veterinary medicine and is no longer considered as a mere nosocomial pathogen. We studied the occurrence of MRSA in veterinary personnel, cats and dogs and the environmental premises in University Veterinary Hospital (UVH). We found the prevalence of MRSA as follows: UVH 2/28 (7.1%) staff, 8/100 (8%) of the pets [5/50 (10%) of the dogs and 3/50 (6%) of the cats)], and 9/28 (4.5%) of the environmental samples. Antibiotic sensitivity tests (AST) show multi-resistance characteristics of the MRSA and the minimum inhibitory concentration (MIC) values for the isolates ranged from 1.5 µg to >256 µg/ml. Molecular typing by using multi-locus sequence typing (MLST), staphylococcal protein A typing (spa typing) and pulsed-field gel electrophoresis (PFGE) was conducted and the results from MLST indicated that an isolate from a veterinary personnel (PG21), typed as ST1241 belonged to the same clonal complex (CC) as the two isolates from two dogs (DG16 and DG20), both being typed as ST59. The PFGE results revealed that the two isolates from two veterinary personnel, PG21 and PG16 belonged to closely related MRSA strains with isolates from dog (DG36) and from environmental surface (EV100) respectively. The fact that PFGE revealed close similarity between isolates from humans, a dog and environmental surfaces indicates the possibility for either of them to be the source of MRSA and the potential routes and risks of spread.