137 research outputs found
The epidemiology and molecular characterization of Burkholderia pseudomallei in Malaysian Borneo
Melioidosis is a potentially fatal disease caused by Burkholderia pseudomallei
which is endemic in Malaysian Borneo. The general aim of this study is to
elucidate the molecular epidemiology of B. pseudomallei in Malaysian Borneo.
Consistent with the Wallace line theory of separation, genotyping showed
Malaysian Borneo clinical B. pseudomallei isolates were more related to
Southeast Asian strains than to Australian strains. Whole genome sequencing
demonstrated that B. pseudomallei from Sarawak were very closely related to
each other. Biochemical testing using VITEK 2 revealed that 25% of B.
pseudomallei from Malaysian Borneo were misidentified as B. cepacia,
suggesting that specificity of that identification system is regionally dependent. A
major and unexpected finding was that 88% of Sarawak B. pseudomallei were
gentamicin susceptible, with these B. pseudomallei being restricted to multilocus
sequence type ST881 and its single locus variant ST997. A novel nonsynonymous
mutation was identified within amrB, an essential component of the
AmrAB-OprA multi-drug efflux pump. Reversion of the mutation to the wild-type
sequence confirmed the role of this mutation in conferring aminoglycoside and
macrolide sensitivity. No environmental B. pseudomallei were isolated from
Sarawak but other Burkholderia species were isolated, prompting the formulation
of hypotheses to explain the lack of environmental B. pseudomallei. Although
inconclusive, experiments showed antagonistic activities by other environmental
Burkholderia spp. recovered from environmental sampling studies towards B.
pseudomallei and also that gentamicin susceptible B. pseudomallei were slightly
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less robust than gentamicin resistant strains in competing with other soil
microorganisms. This thesis contributed to the understanding of the population
structure of B. pseudomallei in Malaysian Borneo, Southeast Asia and globally.
The discovery of gentamicin susceptibility in Sarawak B. pseudomallei has
significant implications for laboratory diagnosis and environmental sampling of B.
pseudomallei in Malaysian Borneo and potentially in other melioidosis endemic
regions. Although the exact distributions, quantification and potential
environmental hazards and implications of B. pseudomallei in Malaysian Borneo
remain uncertain, these studies have led to important research questions now to be
explored. Most immediate is further searching for the proposed existence of an as
yet unidentified localized niche of B. pseudomallei in Malaysian Borneo
Incorrect identification of recent Asian strains of Coxsackievirus A16 as human enterovirus 71: Improved primers for the specific detection of human enterovirus 71 by RT PCR
BACKGROUND: Human enterovirus 71 has emerged as an important pathogen in the Asia Pacific region and it is important to be able to make a rapid and specific diagnosis for outbreak control. Recent Asian strains of Coxsackievirus A16 have changes in the VP1 gene which causes mispriming of widely used primers for human enterovirus 71 specific identification. METHODS: Local strains of Coxsackievirus A16 were sequenced in the VP4 and VP1 genes and using sequence alignment tools, an improved set of primers were designed for specific identification of human enterovirus 71. These primers were evaluated against virus isolates as well as primary clinical specimens. RESULTS: A total of 218 virus strains were tested. All 39 human enterovirus 71 isolates were positive and none of the 38 Coxsackievirus A16, 127 other enteroviruses and 14 prototype flaviviruses and adenoviruses were positive when tested with the new primers. When aliquots of primary specimens known to have yielded human enterovirus 71 were retrospectively tested, we found that within 2 months of collection of the specimens, greater than 90% were positive but that the success rate diminished rapidly to 18% after 2 years storage. CONCLUSIONS: Our new primers will be useful in rapid diagnosis of human enterovirus 71 infection, and can also be used as a screening tool in surveillance programmes for early warning of human enterovirus 71 transmission
Knowledge and Information-Seeking Behaviour on Nasopharyngeal Cancer in Urban and Rural Sarawak, Malaysia
The study examined knowledge and information-seeking behaviour on nasopharyngeal
cancer (NPC) in urban and rural Sarawak. A survey was conducted in Kuching and
Kampung Bengoh involving 121 respondents (44 Kuching; 77 Kampung Bengoh). The
results showed that most respondents do not have family and friends who had NPC, and
their work are not related to NPC. A majority of them had not looked for information on
NPC and only four of them have had screening for NPC. As for intention to obtain more
information on NPC in the next six months, only 46.3% reported likelihood to do so but
20.7% were unlikely to do so because they felt uncomfortable with the subject of cancer
and they did not feel a need to find out more about it. There were no significant
differences between the Kuching and Bengoh respondents on their attitudes towards
information-seeking on cancer and intention to seek information on NPC. However, the
common sources of information on NPC differ for the urban and rural respondents: the
urban respondents relied on the Internet, their doctors and leaflets for NPC information
but the rural respondents depended on the television, radio and newspaper are the main
sources of health information. These results suggest that different channels of information
need to be used to address the low level of awareness on NPC and ambivalent attitudes
towards seeking information on NPC in rural and urban areas in Sarawak
Getting the Message Across: Examining Malaysia’s Covid-19 Public Service Announcement (PSA) Infographics
The current COVID-19 pandemic has become an unprecedented public health crisis and there is much ongoing research investigating its wide-ranging impacts on all areas of society and people's everyday lives. This article presents preliminary findings of an ongoing study that inquires into Malaysia's COVID-19 public service announcement (PSA) infographics and how they convey much-needed information to the general public during the pandemic period. Drawing upon research on infographics in healthcare and health risk communication, the article examines COVID-19 PSA infographics that have been produced in Malaysia and the ways they achieve what they are designed to do. The findings show that the infographics 1) are numerous and mostly presented in the informational and process-based types, 2) cover various topics related to the information on the novel virus, its risks, and recommended preventive and control measures, 3) possess key components of infographic and (4) adopt a three-way process of engaging the target audience. The findings also reveal several key points worth considering in thinking about the infographics, including whether they communicate the right message to the right audience at the right time and whether they are designed according to the principles of message design in health risk communication
Molecular phylogeny of modern coxsackievirus A16
A phylogenetic analysis of VP1 and VP4 nucleotide
sequences of 52 recent CVA16 strains demonstrated
two distinct CVA16 genogroups, A and B,
with the prototype strain being the only member
of genogroup A. CVA16 G-10, the prototype strain,
showed a nucleotide difference of 27.7–30.2% and
19.9–25.2% in VP1 and VP4, respectively, in relation
to other CVA16 strains, which formed two
separate lineages in genogroup B with nucleotide
variation of less than 13.4% and less than 16.3%
in VP1 and VP4, respectively. Lineage 1 strains
circulating before 2000 were later displaced by lineage
2 strains
GETTING THE MESSAGE ACROSS: EXAMINING MALAYSIA’S COVID-19 PUBLIC SERVICE ANNOUNCEMENT (PSA) INFOGRAPHICS
COMMUNICATING PERCEIVED BARRIERS TO ADOPTING NASOPHARYNGEAL CANCER PREVENTIVE BEHAVIOUR
The study investigated how the public communicate their perceived barriers to adopting
the preventive behaviour to minimise risk of Nasopharyngeal cancer (NPC), also known
as nose and throat cancer. The study involved 65 participants living in Kuching and
Samarahan divisions of Sarawak, Malaysia. Semi-structured interviews were conducted
to explore their perceived barriers after reading an NPC pamphlet produced by the
Ministry of Health, Malaysia. The participants reported that living a healthy lifestyle is
more difficult than consulting a doctor. A total of 19% participants reported that living a
healthy lifestyle is hard, 29% remained indifferent and 52% found it easy. They knew
NPC risk could be minimised by reducing smoking, following a healthy diet and
exercising. However, the main perceived barrier was a lack of discipline. For 69% of the
participants, seeing a doctor about NPC was not a barrier, but the remaining
participants fear of facing the truth and the pain of the cancer screening. The findings
suggest that in the context of NPC, recommendations to consult doctors should be more
visibly worded to attract the public’s attention and to motivate action to seek medical
treatment
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