Distribution of pathogenic Leptospira in environmental water and soils of selected recreational forests in Perak, Malaysia.

Leptospirosis is an emerging zoonotic disease endemic in tropical regions. Aiming at assessing the potential infection risks via recreational exposure, the molecular prevalence of pathogenic Leptospira in 14 amenity forests in five selected districts of the state of Perak was determined. Water and soil samples along streams and waterfalls were subjected to culture of leptospires and the pathogenic Leptospira spp. was detected by lipL32-based polymerase chain reaction (PCR). Twenty out of 154 samples (13%) that tested positive for leptospires were mostly soils and still water recorded with tolerable temperatures (22.2- 26.5°C) and pHs (5.73-6.70). The localised prevalence was highly varied among eight positive forests (6.7-41.7%), particularly higher in Kampar and Kinta districts which are the more populated urban areas. The importance of public health surveillance should not be underrated given the high prevalence of Leptospira spp. in forests in close proximity to indigenous settlements, even where the places are clean. Overall, this study discovered a wide distribution of pathogenic Leptospira spp. in recreational areas.

Distribution of pathogenic Leptospira in environmental water and soils of selected recreational forests in Perak, Malaysia

@#Leptospirosis is an emerging zoonotic disease endemic in tropical regions. Aiming at assessing the potential infection risks via recreational exposure, the molecular prevalence of pathogenic Leptospira in 14 amenity forests in five selected districts of the state of Perak was determined. Water and soil samples along streams and waterfalls were subjected to culture of leptospires and the pathogenic Leptospira spp. was detected by lipL32-based polymerase chain reaction (PCR). Twenty out of 154 samples (13%) that tested positive for leptospires were mostly soils and still water recorded with tolerable temperatures (22.226.5°C) and pHs (5.73-6.70). The localised prevalence was highly varied among eight positive forests (6.7-41.7%), particularly higher in Kampar and Kinta districts which are the more populated urban areas. The importance of public health surveillance should not be underrated given the high prevalence of Leptospira spp. in forests in close proximity to indigenous settlements, even where the places are clean. Overall, this study discovered a wide distribution of pathogenic Leptospira spp. in recreational areas.

Pathology and Host Immune Evasion During Human Leptospirosis: a Review.

Human leptospirosis is considered as one of the most widespread and potentially fatal zoonotic diseases that causes high mortality and morbidity in the endemic regions of tropical and subtropical countries. The infection can arise from direct or indirect exposure of human through contaminated environment that contains leptospires or animal reservoirs that carry leptospires. The clinical manifestations during human leptospirosis ranges from asymptomatic, mild infections to severe and life-threatening complications involving multi-organ failures with kidneys, lungs and liver severely affected. Despite much efforts have been put in to unravel the pathogenesis during human leptospirosis, it remains obscure to which extent the host factors or the pathogen itself contribute towards the pathogenesis. Host innate immunity, especially, polymorphonuclear neutrophils and complement system are involved in the first line of defense during human leptospirosis. However, pathogenic Leptospira has acquired diverse evasion strategies to evade from host immunity and establish infection in infected hosts. Hence, in this review, we focus on organs pathology during human leptospiral infection and host evasion strategies employed by Leptospira. A profound understanding on leptospiral immunity and how Leptospira subvert the immune system may provide new insights on the development of therapeutic regimens against this species in future.

Human leukocyte antigen (HLA) class II association in chronic hepatitis B patients with hepatocellular carcinoma in a Malay population: A pilot study

@#Asian countries account for almost three quarter of hepatocellular carcinoma (HCC) reported globally and chronic hepatitis B infection is one of the main contributors. Clinical observations show that Malay patients with chronic hepatitis B and HCC tend to have a worse outcome, when compared to other two major races in Malaysia. The objectives of this study was to determine the frequency of human leukocyte antigen (HLA) class II alleles in chronic hepatitis B patients with HCC among Malays compared to the general population to identify potential associations of HLA alleles with this disease. HLA class II typing was performed in chronic hepatitis B patients with hepatocellular carcinoma (n=12) by -polymerase chain reaction, sequence specific primer (PCR-SSP) method. There were higher allelic frequencies of certain HLA-DQB1 and HLA-DRB1 alleles; HLA-DQB1*03 (07) (41.7%), and HLA-DRB1*12 (41.7% vs 28.6%) and compared to controls (41.7% vs 29.7%). However, there was no significant statistical correlation found when compared with the normal healthy general population. This study provides an insight into the HLA Class II association with chronic hepatitis B and hepatocellular carcinoma in Malays. However, findings from this study should be validated with a larger number of samples using a high resolution HLA typing.

Human leukocyte antigen (HLA) class II association in chronic hepatitis B patients with hepatocellular carcinoma in a Malay population: A pilot study.

Asian countries account for almost three quarter of hepatocellular carcinoma (HCC) reported globally and chronic hepatitis B infection is one of the main contributors. Clinical observations show that Malay patients with chronic hepatitis B and HCC tend to have a worse outcome, when compared to other two major races in Malaysia. The objectives of this study was to determine the frequency of human leukocyte antigen (HLA) class II alleles in chronic hepatitis B patients with HCC among Malays compared to the general population to identify potential associations of HLA alleles with this disease. HLA class II typing was performed in chronic hepatitis B patients with hepatocellular carcinoma (n=12) by -polymerase chain reaction, sequence specific primer (PCR-SSP) method. There were higher allelic frequencies of certain HLA-DQB1 and HLA-DRB1 alleles; HLA-DQB1*03 (07) (41.7%), and HLA-DRB1*12 (41.7% vs 28.6%) and compared to controls (41.7% vs 29.7%). However, there was no significant statistical correlation found when compared with the normal healthy general population. This study provides an insight into the HLA Class II association with chronic hepatitis B and hepatocellular carcinoma in Malays. However, findings from this study should be validated with a larger number of samples using a high resolution HLA typing.

Molecular detection of human adenovirus among hospitalized patients with lower respiratory tract infection in Hospital Sungai Buloh, Malaysia.

Human adenovirus (HAdV) is one of the common pathogens that are responsible for a wide variety of infectious diseases. There are about 54 different adenovirus serotypes that are responsible for respiratory infections in humans. The prevalence of lower respiratory tract infection (LRTI) - associated with HAdV varies throughout different regions. The prevalence of HAdV in Malaysia is rarely investigated and reported despite severity of infection worldwide. This study was undertaken to identify the HAdV types associated with lower respiratory tract infection (LRTI) in Hospital Sungai Buloh, Malaysia between April 2013 until January 2014, a total of 210 specimens were collected from patients hospitalized with LRTI. Human adenovirus was detected using polymerase chain reaction (PCR). The positive products were sequenced and phylogenetic analysis of the virus was performed. Eighteen of 210 specimens (8.57%) were positive with HAdV infection. Based on the phylogenetic analysis study, HAdV-7 strains were the most common serotype with 11 cases, followed by HAdV-1, HAdV-2 and HAdV-4 with 2 cases each and one case of HAdV-5. The HAdV strains in this study were closely related to strains in Singapore and India. In this study, HAdV infection from LRTI patients in Hospital Sungai Buloh Malaysia were caused by different types of adenovirus mainly HAdV-7. This study will become a reference for further epidemiological study in this country.

Ex Vivo Evaluation of Thymus daenensis as an Antioxidant and Antibacterial Medicinal Herb.

Herbal medicines are defined as traditionally used natural products. The current study in an attempt try to investigate the antibacterial activity on extended spectrum beta-lactamases (ESBL), methalo beta-lactamases (MBL) producing gram negative bacteria and methicillin resistant Staphylococcus aureus (MRSA) and subsequently, to determine the antioxidant activity of Thymus daenensis. For this reasons, firstly cytotoxicity of T. daenensis was determined by MTT assay. Then, essential oil was subjected for antibacterial and antioxidant activity. Our results demonstrated that 15 mg/ml concentration of T. daenensis inhibited both P. aeruginosa producing MBL and E.coli producing ESBL, while this value was 25 mg/ml concentration for MRSA inhibition. The association between phenolic compound and antioxidant activity was found for the ABTS•+ method (43.52%) in the lowest level, while, for FRAD and DPPH• methods the opposite story occurred (70.5% correlation for DPPH• and 50.9% for FRAD). Our findings suggested that T. daenensis has a potential herbal medicine that should be considered as an antibacterial and antioxidant with very low toxicity.

Influenza vaccination among Malaysian healthcare workers: a survey of coverage and attitudes.

BACKGROUND: Healthcare workers (HCWs) are at increased risk of getting influenza than the general population, therefore putting patients at risk of nosocomial infection. Influenza vaccination coverage among HCWs is low despite the availability of a safe and effective vaccine. However, the reasons for such a poor uptake are not well reported in Malaysia. This study aimed at assessing the rate of influenza vaccination uptake, knowledge and attitude of healthcare workers regarding influenza, and employers' policy on influenza vaccination. METHODS: A cross-sectional questionnaire survey was conducted in three hospitals in the Klang Valley. Mann-Whitney test was used to assess possible differences in knowledge and attitude towards flu vaccination and the χ2 was used for categorical variables. Analyses were performed with SPSS 22.0. RESULTS: A total of 690 questionnaires were distributed; 527 were returned (giving a response rate of 76.4%. The vaccine uptake was 51.4% with the majority (83.5%) of those believing they were vaccinated to protect themselves. Higher proportion of vaccinated HCWs (p <0.05) agreeing to the fact that influenza is a serious threat to their health, however, 10% were not sure of its safety. Eighty-three (15.7%) claimed their employers did not have a vaccination policy, while 43.3% were not sure if their employers have vaccination policy. CONCLUSION: This study has demonstrated more than half of the healthcare workers were vaccinated, with a significant proportion of the healthcare workers believed they were vaccinated to protect themselves, while most of those that were not vaccinated claimed they are worried about the safety of the vaccine. Most employers did not have a flu vaccination policy in place. Hence, the need for government to enforce such policy and make annual flu vaccination free and compulsory for all healthcare workers.

The rationale behind antibiotic resistance pattern in Klebsiella pneumoniae.

Presently, there is an increase in antibiotic resistance in bacteria, due to relax prescription of antibiotics, especially in Iran. Undoubtedly, in toxin antitoxin (TA) system, a toxin neutralized by antitoxin, which known as a potent antimicrobial target; but there is no extensive survey on the prevalence of TA loci in large scale of Klebsiella pneumoniae. Therefore, this study aims to determine the prevalence of different TA loci in clinical and environmental K. pneumoniae isolates. For this reason, 48 K. pneumoniae clinical isolates and 49 K. pneumoniae environmental isolates were subjected for evaluation of different TA loci. The results of current study indicated that there is no association between antibiotic resistances and presence of TA loci in clinical and environmental K. pneumoniae. The role of TA loci as a potent target in antibiotic resistant K. pneumoniae has been complicated. Therefore, more studies should be performed to explain why TA loci are presented in K. pneumoniae and what is the rationale behind antibiotic resistant K. pneumoniae?

Development of two salmonella-based oral vaccines against human respiratory syncytial virus.

Human respiratory syncytial virus is the most common cause of bronchiolitis and other respiratory infections in infants and the elderly worldwide. We have developed two new oral vaccines using Salmonella typhi TY21a to carry and express the immunogenic epitopes of RSV fusion (F) and attachment (G) glycoproteins on its surface, separately. To evaluate the efficacy of the designed vaccines, BALB/c mice were orally immunized and then infected with RSV. Immune response analyses showed that cellmediated, mucosal and humoral immunity in the vaccinated mice were significantly enhanced compared to the control group. Both vaccines generated a balanced Th1/Th2 immune response which is crucial for efficiency of vaccines against RSV. Furthermore, histopathological examination proved that these vaccines were safe as they did not cause any Th2-associated adverse effects in the lungs of RSV-infected mice. The findings of this research suggest that Salmonella-F and Salmonella-G vaccine candidates may have strong potential to prevent RSV infection.

Naturally occurring hepatitis B virus surface antigen mutant variants in Malaysian blood donors and vaccinees.

Hepatitis B virus surface mutants are of enormous importance because they are capable of escaping detection by serology and can infect both vaccinated and unvaccinated populations, thus putting the whole population at risk. This study aimed to detect and characterise hepatitis B-escaped mutants among blood donors and vaccinees. One thousand serum samples were collected for this study from blood donors and vaccinees. Hepatitis B surface antigen, antibodies and core antibodies were tested using a commercial enzyme-linked immunosorbent assay (ELISA) kit. DNA detection was performed via nested polymerase chain reaction (PCR), and the S gene was sequenced and analysed using bioinformatics. Of the 1,000 samples that were screened, 5.5% (55/1,000) were found to be HBsAg-negative and anti-HBc- and HBV DNA-positive. All 55 isolates were found to belong to genotype B. Several mutations were found across all the sequences from synonymous and non-synonymous mutations, with the most nucleotide mutations occurring at position 342, where adenine was replaced by guanine, and cytosine at position 46 was replaced by adenine in 96.4% and 98% of the isolates, respectively. Mutation at position 16 of the amino acid sequence was found to be common to all the Malaysian isolates, with 85.7% of the mutations occurring outside the major hydrophilic region. This study revealed a prevalence of 5.5% for hepatitis B-escaped mutations among blood donors and vaccinated undergraduates, with the most common mutation being found at position 16, where glutamine was substituted with lysine.

Distribution of extended spectrum beta-lactamase resistance genes among nosocomial imipenem resistant A. Baumannii strains harboring BLAoxa-23 carbapenemases isolated from Ilam and Tehran.

Antimicrobial susceptibility and ESBLs genes of 42 imipenem resistant A. baumannii carried out by DDST and PCR. The most antimicrobial agents against A. baumannii strains, harboring blaOXA-23-like carbapenemases, were meropenem (33.4 percent), piperacillin-tazobactam (23.9 percent), ceftazidime (14.3 percent) and gatifoxacin (19.1 percent), respectively. All the 42 isolates harbored the blaTEM gene, but the bla SHV and VEB genes were not present among all the isolates. With the exception of seven isolates, all the A. baumannii strains harbor blaTEM showed ESBL positivity in DDST. The result of this study show that resistance against antimicrobial agents, especially carbapenems, has increased and that blaTEM harboring A. baumannii strains can be help the blaOXA-like carbapenemase genes to code for resistance against carbapenem antibiotics.

First detected human bocavirus in a Malaysian child with pneumonia and pre-existing asthma: a case report.

Human bocavirus (HBoV) is a newly discovered parvovirus associated with respiratory disease in children. There are many reports worldwide on the endemicity of this virus. Since it is relatively new, detection in clinical laboratories is not routinely performed. We describe the first detection of HBoV in Malaysia in a 13-month-old boy with pneumonia and underlying asthma. The infective agent was confirmed by molecular methods.

Effect of tannin extract against Pseudomonas aeruginosa producing metallo beta-lactamase.

Carbapenems are the most potent beta-lactam agents with a broad-spectrum activity against Gram-negative and Gram-positive bacteria. They are stable in the presence of penicillinases and cephalosporinases. This study was focused on frequency of metallo beta- lactamase (MBL) among Pesudomonas aeruginosa strains isolated in patients with urinary tract infection, effect of tannin against PA positive strains which produced blaVIM or blaIMP and both of these genes (Species). Detection of MBL was performed by phonotypic and genotypic methods. Tannin extract was tested against P. aeruginosa producing MBL. During the study period, 240 P. aeruginosa isolates were identified. Among them 64 (26.6 percent) isolates were imipenem non-susceptible and confirmed by imipenem/EDTA. Our results revealed that the growth of blaVIM positive P. aeruginosa inhibited at 15 microg/ml concentration. The experiment repeated for blaIMP-positive P. aeruginosa and P. aeruginosa which harbored blaIMP and blaVIM, the results showed 35 microg/ml was the best concentration for inhibition of P. aeruginosa-positive blaIMP and also P. aeruginosa blaIMP and blaVIM. In conclusion, tannin was effective against P. aeruginosa producing blaVIM and blaIMP and both of them so it can be substituted with common antibiotics. The result showed significantly P. aeruginosa-harbored blaIMP was more responsible for imipenem resistance than P. aeruginosa-positive blaVIM. Interestingly, tannin was more effective against MBL-P. aeruginosa in comparison with current antibiotics.

mec-associated dru typing in the epidemiological analysis of ST239 MRSA in Malaysia.

The usefulness of mec-associated dru typing in the epidemiological analysis of methicillin-resistant Staphylococcus aureus (MRSA) isolated in Malaysia was investigated and compared with pulsed-field gel electrophoresis (PFGE), multilocus sequence typing (MLST), and spa and SCCmec typing. The isolates studied included all MRSA types in Malaysia. Multilocus sequence type ST188 and ST1 isolates were highly clonal by all typing methods. However, the dru typing of ST239 isolates produced the clearest discrimination between SCCmec IIIa and III isolates, yielding more subtypes than any other method. Evaluation of the discriminatory power for each method identified dru typing and PFGE as the most discriminatory, with Simpson's index of diversity (SID) values over 89%, including an isolate which was non-typeable by spa, but dru-typed as dt13j. The discriminatory ability of dru typing, especially with closely related MRSA ST239 strains (e.g., Brazilian and Hungarian), underscores its utility as a tool for the epidemiological investigation of MRSA.

Surface display of respiratory syncytial virus glycoproteins in Lactococcus lactis NZ9000.

AIMS: A system for displaying heterologous respiratory syncytial virus (RSV) glycoproteins on the surface of Lactococcus lactis NZ9000 was developed. METHODS AND RESULTS: Fusion of the USP45 signal peptide and the cA (C terminus of the peptidoglycan-binding) domains of AcmA, a major autolysin from L. lactis, to the N- and C-terminal of the target proteins, respectively, was carried out. The target protein was the major immunogenic domain of either the F (40.17-kDa) or G (11.49-kDa) glycoprotein domains of the RSV. Whole-cell ELISA readings obtained after 24 h of induction showed an increase in protein expression as the cA domain repeats increased, for the G glycoprotein of RSV. On the other hand, the F glycoprotein indicated decreasing expression levels as the number of cA domain repeats increased. The difference in the expression levels of the F and G domains may be attributed to the different sizes of the antigenic domains. CONCLUSIONS: The size and properties of the target proteins are vital in determining the amount of antigenic domains being displayed on the surface of live cells. SIGNIFICANCE AND IMPACT OF THE STUDY: The system demonstrated here can aid in the utilization of the generally regarded as safe (GRAS) bacteria L. lactis, as a vaccine delivery vehicle to surface display the antigenic proteins of RSV.

Glycosylation is not necessary for recognition of the fusion glycoprotein domain of the human respiratory syncytial virus by a polyclonal antibody.

Human respiratory syncytial virus (HRSV) is a leading pathogen causing lower respiratory tract infections in infants and young children worldwide. In line with the development of an effective vaccine against HRSV, a domain of the fusion (F) glycoprotein of HRSV was produced and its immunogenicity and antigenic properties, namely the effect of deficient glycosylation was examined. A His-tagged recombinant F (rF) protein was expressed in Escherichia coli, solubilized with 8 mol/l urea, purified by the Ni-NTA affinity chromatography and used for the raising of a polyclonal antibody in rabbits. The non-glycosylated rF protein proved to be a strong immunogen that induced a polyclonal antibody that was able to recognize also the glycosylated F1 subunit of native HRSV. The other way around, a polyclonal antibody prepared against the native HRSV was able to react with the rF protein. These results indicated that glycosylation was not necessary for the F domain aa 212-574 in order to be recognized by the specific polyclonal antibody.

Effect of organic acids on Escherichia coli O157:H7 and Staphylococcus aureus contaminated meat.

Appropriate and safe antibacterial agents able to decontaminate meat surfaces have long been big concern of meat industry. In an attempt to manage beef carcass contamination, spray wash treatments utilizing three concentrations (1, 1.5 and 2%) of acetic, lactic, propionic and formic acids were performed to evaluate their efficacy in reducing numbers of Escherichia coli O157:H7 and Staphylococcus aureus on meat tissues. The procured beef pieces of freshly slaughtered animals were decontaminated with hot water and then inoculated with E. coli O157:H7 and S. aureus individually which then were spray washed with organic acids separately. The total plate count of the treated samples showed that the populations of bacteria decreased after being exposed to organic acids. Spray wash of formic acid resulted in the highest reduction of both bacterial species on meat surface. Significantly, higher log reductions were obtained for S. aureus than E. coli O157:H7. It was concluded that organic acids are highly effective in decontaminating meat surfaces and organic acids are shown to be safe, simple, efficient, and cheap modality of meat decontamination which can be highly recommended for industrial scales.

Rubella vaccination programme in Malaysia: analysis of a seroprevalence study in an antenatal clinic.

In many developed countries, the incidence of rubella and congenital rubella syndrome (CRS) is considered to be negligible due to the availability of an effective vaccine. However, in Malaysia, several CRS cases are seen every year. This casts doubt on the effectiveness of the rubella vaccination programme. Very few seroprevalence studies were done over the years, making it difficult to discuss the effectiveness of the vaccination programme. The objective of this study is to determine the prevalence of rubella immunity among pregnant women attending antenatal clinics in a local teaching hospital. The hospital database on rubella immunity was assessed retrospectively from August 2001 to June 2002. A cross-sectional study of interviewed method as well as determination of rubella immunity by laboratory tests were carried out in July 2002. A total of 414 women were included, of whom 134 women were interviewed. The rubella immunity status was 92.3%. Based on this figure, rubella vaccination programme in Malaysia is a success despite the presence of CRS cases. Malaysia must ensure rubella vaccine coverage among target groups is high in order to minimise CRS cases.