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Abstract

Background: Malaysia is hyperendemic country for dengue, where all four dengue viruses (DENV) are co-circulating within the community. The presence of DENV genotype 3 (DENV-3) was first described by Lim et al as the main causative agent responsible for the 1973 dengue epidemics in Malaysia. From then on, DENV-3 became ubiquitous in Malaysia that exhibited a cyclical outbreak pattern at interval of seven to eight years. Several studies have demonstrated the presence of DENV-3 subgenotypes I and II in Malaysia. Here, we present evidence at emergence of subgenotype III in Malaysia. Methods: A random subset of DENV-3 virus samples, isolated in year 2010, was obtained from Diagnostic Virology Repository at University Malaya Medical Center. The virus was propagated through one round passage in cell culture. Viral RNA was extracted from cell culture supernatant and the virus envelope (E) gene was amplified and sequenced. Complete E gene sequences of DENV-3 were examined in the study, together with sequences retrieved from the GenBank. Phylogenetic relationship of these viruses is presented. Results: The phylogenetic analysis based on the complete E gene of DENV-3 isolated from Malaysia along with representative strains obtained from the GenBank demonstrates the presence of 5 distinct DENV-3 subgenotypes. All the Malaysia isolates in this study clustered under the subgenotype III group, which forms a distinct Malaysia lineage. This Malaysia lineage grouped closely with DENV-3 strain isolated from Singapore during the 2005 outbreaks. These viruses formed a geographically distinctive clade within the subgenotype III group. Conclusion: In summary, our study demonstrates the emergence of DENV-3 subgenotype III in Malaysia in 2010. Further study is underway to monitor and evaluate the possibility of this new subgenotype to emerge as the dominant circulating DENV-3 in Malaysia.
e272 15th ICID Abstracts / International Journal of Infectious Diseases 16S (2012) e158–e316
Conclusion: SSU based PCR-RFLP tool discriminated Cryp-
tosporidium into two species and C. hominis was more prevalent
in this area. GP60 sequence based subtyping has revealed the coex-
istence of C. hominis with C. meleagridis/C. parvum and also C.
hominis subtypes. These species were missed by SSU rRNA based
RFLP analysis which detected only C. hominis in concurrent infec-
tions. The existence of many C. hominis and C. parvum subgenotype
families and subtypes within the subgenotype families reveals the
complexity of Cryptosporidium transmission and this heterogeneity
indicates stable cryptosporidiosis transmission in North India.
http://dx.doi.org/10.1016/j.ijid.2012.05.926
Type: Poster Presentation
Final Abstract Number: 46.055
Session: Emerging Infectious Diseases
Date: Friday, June 15, 2012
Time: 12:45-14:15
Room: Poster & Exhibition Area
A survey of preparedness and risk communication in US and
Thai zoos: using highly pathogenic Avian influenza as a model
R. Pattanarangsan1, M. Stoskopf2, A. Sommanustaweechai3,,P.
Cowen2
1North Carolina State University, Raleigh, NC, USA
2College of Veterinary Medicine, Raleigh, NC, USA
3Zoological Park Organization of Thailand, Bangkok, Thailand
Background: The ecology of zoonotic infections are particularly
complex in zoological garden settings. It involves endangered and
non-endangered resident zoo animals, free living wildlife, millions
of human visitors, zookeepers that can come into very intimate
contact with animals. Thus, Zoos are potentially one critical point
for wildlife zoonosis to emerge. The best known recent examples
of this phenomenon are the episodes of Highly Pathogenic Avian
Influenza H5N1(HPAI) and West Nile virus. Meanwhile, zoos are
also the place where the public seeks information during zoonotic
disease outbreaks that involve any kind of wildlife and a major
setting for conservation education.
Methods: This study aimed to assess the existing stance of zoos
in Thailand and United States concerning the communication of
potential risks using HPAI as a model. We used a convenience sam-
pling strategy for collection of data targeting personnel from 8
zoos in Thailand and in the United States. The survey was a self-
administered, web based instrument which included 22 questions
focusing on respondent demographics, mental models for HPAI,
adherence to risk communication principles as expounded by Peter
Sandman and assessment of zoo preparedness.
Results: Based on 38 responses, 95% agreed that the outbreak
of HPAI can cause negative emotion or outrage. When we probed
the underlying mental model for the negative emotions or out-
rage, the top three categories included the catastrophic nature of
HPAI, trust accrued by communicating authority or agency and the
inherent dread of a high mortality, high impact disease. Timing of
zoo response, as the outbreak continued, was characterized by 37%
indicating they would be likely to communicate with the public
immediately, 5% would wait until a greater number of cases was
available and 37% would wait for official declaration of the out-
break. If HPAI were to occur in a zoo, the respondents felt that
wild bird “stop over” was the most likely cause. Zoos indicate that
preparedness status was much more than enough (3%), more than
enough (16%), enough (35%), not enough (32%), nearly nothing
(14%).
Conclusion: The effect of location, country, and respondent
strata was analyzed.
http://dx.doi.org/10.1016/j.ijid.2012.05.927
Type: Poster Presentation
Final Abstract Number: 46.056
Session: Emerging Infectious Diseases
Date: Friday, June 15, 2012
Time: 12:45-14:15
Room: Poster & Exhibition Area
Emergence of dengue virus genotype 3 subgenotype III in
Malaysia
K.-K. Tan, N.I. Zulkifle, S. Syuhaida, M.-H. Shu, A. Sazaly
University of Malaya, Kuala Lumpur, Malaysia
Background: Malaysia is hyperendemic country for dengue,
where all four dengue viruses (DENV) are co-circulating within
the community. The presence of DENV genotype 3 (DENV-3) was
first described by Lim et al as the main causative agent respon-
sible for the 1973 dengue epidemics in Malaysia. From then on,
DENV-3 became ubiquitous in Malaysia that exhibited a cyclical
outbreak pattern at interval of seven to eight years. Several studies
have demonstrated the presence of DENV-3 subgenotypes I and II in
Malaysia. Here, we present evidence at emergence of subgenotype
III in Malaysia.
Methods: A random subset of DENV-3 virus samples, isolated
in year 2010, was obtained from Diagnostic Virology Repository
at University Malaya Medical Center. The virus was propagated
through one round passage in cell culture. Viral RNA was extracted
from cell culture supernatant and the virus envelope (E) gene was
amplified and sequenced. Complete E gene sequences of DENV-3
were examined in the study, together with sequences retrieved
from the GenBank. Phylogenetic relationship of these viruses is
presented.
Results: The phylogenetic analysis based on the complete E
gene of DENV-3 isolated from Malaysia along with representative
strains obtained from the GenBank demonstrates the presence of
5 distinct DENV-3 subgenotypes. All the Malaysia isolates in this
study clustered under the subgenotype III group, which forms a dis-
tinct Malaysia lineage. This Malaysia lineage grouped closely with
DENV-3 strain isolated from Singapore during the 2005 outbreaks.
These viruses formed a geographically distinctive clade within the
subgenotype III group.
Conclusion: In summary, our study demonstrates the emer-
gence of DENV-3 subgenotype III in Malaysia in 2010. Further study
is underway to monitor and evaluate the possibility of this new
subgenotype to emerge as the dominant circulating DENV-3 in
Malaysia.
http://dx.doi.org/10.1016/j.ijid.2012.05.928
... The homotypic transmission cycle with DENV-3 as the dominant serotype occurred in the years 1982, 1986, 1992-1995 and 2002 [7]. In 2010, we reported the emergence of DENV-3 genotype III (DENV-3/III) [11] that coincided temporally with the anticipated DENV-3 major outbreak cycle [12]. The DENV-3/III is one of the DENV genotypes that has been associated with high transmissibility and widespread global distribution [13]. ...
Article
Dengue virus type 3 genotype III (DENV-3/III) is widely distributed in most dengue-endemic regions. It emerged in Malaysia in 2008 and autochthonously spread in the midst of endemic DENV-3/I circulation. The spread, however, was limited and the virus did not cause any major outbreak. Spatiotemporal distribution study of DENV-3 over the period between 2005 and 2011 revealed that dengue cases involving DENV-3/III occurred mostly in areas without pre-existing circulating DENV-3. Neutralisation assays performed using sera of patients with the respective infection showed that the DENV-3/III viruses can be effectively neutralised by sera of patients with DENV-3 infection (50% foci reduction neutralisation titres (FRNT 50 ) > 1300). Sera of patients with DENV-1 infection (FRNT 50 ⩾ 190), but not sera of patients with DENV-2 infection (FRNT 50 ⩽ 50), were also able to neutralise the virus. These findings highlight the possibility that the pre-existing homotypic DENV-3 and the cross-reacting heterotypic DENV-1 antibody responses could play a role in mitigating a major outbreak involving DENV-3/III in the Klang Valley, Malaysia.
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