Peter Seah Keng Tok

Dr. Peter Seah Keng Tok

orcid

Research Focus & Metrics

Academic Career Length

9Years (2018-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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22 April 2020 in PLOS ONE
Verified
Journal Article
Open access
PDF file
PTPeter Seah Keng Tok
Peter Seah Keng Tok
SLSu May Liew
Su May Liew
LWLi Ping Wong
Li Ping Wong
ARAsmah Razali
Asmah Razali
THARANI LOGANATHANTHARANI LOGANATHAN
THARANI LOGANATHAN
NKNaim Abdul Kadir
Naim Abdul Kadir
The monitoring of tuberculosis (TB) treatment outcomes and examination of the factors affecting these outcomes are important for evaluation and feedback of the national TB control program. This study aims to assess the TB treatment outcomes among patients registered in the national TB surveillance database in Malaysia from 2014 until 2017 and identify factors associated with unsuccessful treatment outcomes and all-cause mortality. Using registry-based secondary data, a retrospective cohort study was conducted. TB patients’ sociodemographic characteristics, clinical disease data and treatment outcomes at one-year surveillance were extracted from the database and analyzed. Logistic regression analysis was used to determine factors associated with unsuccessful treatment outcomes and all-cause mortality. A total of 97,505 TB cases (64.3% males) were included in this study. TB treatment success (cases categorized as cured and completed treatment) was observed in 80.7% of the patients. Among the 19.3% patients with unsuccessful treatment outcomes, 10.2% died, 5.3% were lost to follow-up, 3.6% had outcomes not evaluated while the remaining failed treatment. Unsuccessful TB treatment outcomes were found to be associated with older age, males, foreign nationality, urban dwellers, lower education levels, passive detection of TB cases, absence of bacille Calmette-Guerin (BCG) scar, underlying diabetes mellitus, smoking, extrapulmonary TB, history of previous TB treatment, advanced chest radiography findings and human immunodeficiency virus (HIV) infection. Factors found associated with all-cause mortality were similar except for nationality (higher among Malaysians) and place of residence (higher among rural dwellers), while smoking and history of previous TB treatment were not found to be associated with all-cause mortality. This study identified various sociodemographic characteristics and TB disease-related variables which were associated with unsuccessful TB treatment outcomes and mortality; these can be used to guide measures for risk assessment and stratification of TB patients in future.

23 May 2022 in Emerging Microbes & Infections
Verified
Journal Article
Open access
JSJing Lian Suah
Jing Lian Suah
BTBoon Hwa Tng
Boon Hwa Tng
PTPeter Seah Keng Tok
Peter Seah Keng Tok
MHmasliyana husin
masliyana husin
TTThevesh Thevananthan
Thevesh Thevananthan
SSSheamini Sivasampu
Sheamini Sivasampu
Given emerging evidence of immune escape in the SARS-CoV-2 Omicron viral variant, and its dominance, effectiveness of heterologous and homologous boosting schedules commonly used in low-to-middle income countries needs to be re-evaluated. We conducted a test-negative design using consolidated national administrative data in Malaysia to compare the effectiveness of homologous and heterologous BNT162b2, CoronaVac, and AZD1222 booster vaccination against SARS-CoV-2 infection in predominant-Delta and predominant-Omicron periods. Across both periods, homologous CoronaVac and AZD1222 boosting demonstrated lower effectiveness than heterologous boosting for CoronaVac and AZD1222 primary vaccination recipients and homologous BNT162b2 boosting (PPP). Broadly, marginal effectiveness was smaller by 40 to 50 percentage points in the Omicron period than the Delta period. Without effective and accessible second-generation vaccines, heterologous boosting using BNT162b2 for inactivated and vectored primary vaccination recipients is preferred.

30 June 2022 in Expert Review of Vaccines
Verified
Journal Article
Open access
SCSunate Chuenkitmongkol
Sunate Chuenkitmongkol
RSRontgene Solante
Rontgene Solante
EBErlina Burhan
Erlina Burhan
SCSuwat Chariyalertsak
Suwat Chariyalertsak
NCNan-Chang Chiu
Nan-Chang Chiu
SGSEA Vaccine Effectiveness Expert Working Group
SEA Vaccine Effectiveness Expert Working Group
COVID-19 vaccines have been highly effective in reducing morbidity and mortality during the pandemic. While primary series vaccination rates are generally high in Southeast Asian (SEA) countries, v...

24 November 2021 in Vaccines
Verified
Journal Article
Open access
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JSJing Lian Suah
Jing Lian Suah
PTPeter Seah Keng Tok
Peter Seah Keng Tok
SOSu Miin Ong
Su Miin Ong
MHmasliyana husin
masliyana husin
BTBoon Hwa Tng
Boon Hwa Tng
KPKalaiarasu M. Peariasamy
Kalaiarasu M. Peariasamy
Malaysia rolled out a diverse portfolio of predominantly three COVID-19 vaccines (AZD1222, BNT162b2, and CoronaVac) beginning 24 February 2021. We evaluated vaccine effectiveness with two methods, covering 1 April to 15 September 2021: (1) the screening method for COVID-19 (SARS-CoV-2) infection and symptomatic COVID-19; and (2) a retrospective cohort of confirmed COVID-19 cases for COVID-19 related ICU admission and death using logistic regression. The screening method estimated partial vaccination to be 48.8% effective (95% CI: 46.8, 50.7) against COVID-19 infection and 33.5% effective (95% CI: 31.6, 35.5) against symptomatic COVID-19. Full vaccination is estimated at 87.8% effective (95% CI: 85.8, 89.7) against COVID-19 infection and 85.4% effective (95% CI: 83.4, 87.3) against symptomatic COVID-19. Among the cohort of confirmed COVID-19 cases, partial vaccination with any of the three vaccines is estimated at 31.3% effective (95% CI: 28.5, 34.1) in preventing ICU admission, and 45.1% effective (95% CI: 42.6, 47.5) in preventing death. Full vaccination with any of the three vaccines is estimated at 79.1% effective (95% CI: 77.7, 80.4) in preventing ICU admission and 86.7% effective (95% CI: 85.7, 87.6) in preventing deaths. Our findings suggest that full vaccination with any of the three predominant vaccines (AZD1222, BNT162b2, and CoronaVac) in Malaysia has been highly effective in preventing COVID-19 infection, symptomatic COVID-19, COVID-19-related ICU admission, and death.

15 September 2018 in BMC Medical Ethics
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Journal Article
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FTFERCAP Multi-Country Research Team
FERCAP Multi-Country Research Team
JKJuntra Karbwang
Juntra Karbwang
NKNut Koonrungsesomboon
Nut Koonrungsesomboon
CTCristina E. Torres
Cristina E. Torres
EJEdlyn B. Jimenez
Edlyn B. Jimenez
SYSubhash Yadav
Subhash Yadav
The use of lengthy, detailed, and complex informed consent forms (ICFs) is of paramount concern in biomedical research as it may not truly promote the rights and interests of research participants. The extent of information in ICFs has been the subject of debates for decades; however, no clear guidance is given. Thus, the objective of this study was to determine the perspectives of research participants about the type and extent of information they need when they are invited to participate in biomedical research. This multi-center, cross-sectional, descriptive survey was conducted at 54 study sites in seven Asia-Pacific countries. A modified Likert-scale questionnaire was used to determine the importance of each element in the ICF among research participants of a biomedical study, with an anchored rating scale from 1 (not important) to 5 (very important). Of the 2484 questionnaires distributed, 2113 (85.1%) were returned. The majority of respondents considered most elements required in the ICF to be ‘moderately important’ to ‘very important’ for their decision making (mean score, ranging from 3.58 to 4.47). Major foreseeable risk, direct benefit, and common adverse effects of the intervention were considered to be of most concerned elements in the ICF (mean score = 4.47, 4.47, and 4.45, respectively). Research participants would like to be informed of the ICF elements required by ethical guidelines and regulations; however, the importance of each element varied, e.g., risk and benefit associated with research participants were considered to be more important than the general nature or technical details of research. Using a participant-oriented approach by providing more details of the participant-interested elements while avoiding unnecessarily lengthy details of other less important elements would enhance the quality of the ICF.

30 April 2022 in International Journal of Infectious Diseases
Verified
Journal Article
Open access
MHmasliyana husin
masliyana husin
PTPeter Seah Keng Tok
Peter Seah Keng Tok
JSJing Lian Suah
Jing Lian Suah
TTThevesh Thevananthan
Thevesh Thevananthan
BTBoon Hwa Tng
Boon Hwa Tng
SSSheamini Sivasampu
Sheamini Sivasampu
In this study, we aimed to investigate vaccine effectiveness (VE) against SARS-CoV-2 infections among adolescents aged 12 to 17 years in Malaysia and examine potential VE differences after full vaccination. We consolidated data on COVID-19 testing, vaccination, and outcomes for all public school-going adolescents in Malaysia from September 1, 2021, to December 31, 2021, and estimated the VE against SARS-CoV-2 infections during this period. Cases were defined as positive tests, either by reverse transcriptase- PCR (RT-PCR) or rapid antigen (RTK-Ag) testing, while controls were negative tests. Secondarily, we restricted the analysis to all tests performed in December 2021 and compared VE by month of full vaccination. A total of 175,880 eligible tests (53.4% or 93,995 RT-PCR tests) were included. After full vaccination with BNT162b2, VE against SARS-CoV-2 infections was 65.7% (95% confidence interval [CI] 64.4, 66.9) over the study period. When restricted to tests in December 2021, VEs for those fully vaccinated in September 2021, October 2021, and November 2021 were comparable (60.6% [95% CI 23.7, 81.5], 56.9% [95% CI 51.1, 62.0], and 65.7% [95% CI 59.8, 70.7] respectively). Among adolescents, full vaccination with BNT162b2 offered considerable protection against SARS-CoV-2 infections over at least three months without substantial evidence of waning.