1.Sequence analysis on the mitochondrial COXI gene of recent clinical isolates of Plasmodium knowlesi in Klang valley, peninsular Malaysia
Mun Yik Fong* ; Yee-Ling Lau ; Lit-Chien Chin ; Abdulsalam M.Q. Al-Mekhlafi
Tropical Biomedicine 2011;28(2):457-463
The cytochrome oxidase subunit I (COXI) gene sequences of three recent (2007-
2008) clinical Plasmodium knowlesi isolates from Klang Valley, peninsular Malaysia, were
determined and compared with those of older (1960’s) peninsular Malaysia, recent isolates
from Sarawak (on Borneo Island), and an isolate from Thailand. Multiple alignment of the
sequences showed that the three clinical isolates were more similar to the older peninsular
Malaysia isolates than to those from Sarawak and Thailand. Phylogenetic tree based on the
COXI sequences revealed three distinct clusters of P. knowlesi. The first cluster consisted of
isolates from peninsular Malaysia, the second consisted of Sarawak isolates and the third
composed of the Thailand isolate. The findings of this study highlight the usefulness of
mitochondrial COXI gene as a suitable marker for phylogeographic studies of P. knowlesi.
2.Seroprevalence of Sarcocystis falcatula in Two Islands of Malaysia using Recombinant Surface Antigen 4
Tengku-Idris Tengku Idzzan NADZIRAH ; Fong Mun YIK ; Lau Yee LING
The Korean Journal of Parasitology 2020;58(1):1-5
Sarcocystosis was diagnosed worldwide by serodiagnostic tests utilising the whole parasite, for which the protozoa were maintained in vitro are more costly. In this study, antigenicity of Sarcocystis falcatula recombinant protein (rSfSAG4) was investigated towards the local communities of Pangkor and Tioman Islands and its seroprevalence was surveyed in these islands. A total of 348 human sera were tested using rSfSAG4 by Western blot and ELISA. High prevalence of sarcocystosis was observed in Tioman Island (80.6%) than in Pangkor Island (50.0%) by Western blot. In ELISA, the seroprevalence observed in Tioman Island was 45.9%, whereas in Pangkor Island 63.0%. In other parasitic infections, the prevalence was 34.0% by Western blot and 46.0% by ELISA. In healthy control group, 7% by Western blot and 8% by ELISA showed positivity to rSfSAG4. It is suggested SfSAG4 is a candidate antigen to measure seroprevalence of sarcocystosis.
4.Pericarditis and myocarditis after COVID-19 mRNA vaccination in a nationwide setting.
Jonathan YAP ; Mun Yee THAM ; Jalene POH ; Dorothy TOH ; Cheng Leng CHAN ; Toon Wei LIM ; Shir Lynn LIM ; Yew Woon CHIA ; Yean Teng LIM ; Jonathan CHOO ; Zee Pin DING ; Ling Li FOO ; Simin KUO ; Yee How LAU ; Annie LEE ; Khung Keong YEO
Annals of the Academy of Medicine, Singapore 2022;51(2):96-100
INTRODUCTION:
Despite reports suggesting an association between COVID-19 mRNA vaccination and pericarditis and myocarditis, detailed nationwide population-based data are sparsely available. We describe the incidence of pericarditis and myocarditis by age categories and sex after COVID-19 mRNA vaccination from a nationwide mass vaccination programme in Singapore.
METHODS:
The incidence of adjudicated cases of pericarditis and myocarditis following COVID-19 mRNA vaccination that were reported to the vaccine safety committee between January to July 2021 was compared with the background incidence of myocarditis in Singapore.
RESULTS:
As of end July 2021, a total of 34 cases were reported (9 pericarditis only, 14 myocarditis only, and 11 concomitant pericarditis and myocarditis) with 7,183,889 doses of COVID-19 mRNA vaccine administered. Of the 9 cases of pericarditis only, all were male except one. The highest incidence of pericarditis was in males aged 12-19 years with an incidence of 1.11 cases per 100,000 doses. Of the 25 cases of myocarditis, 80% (20 cases) were male and the median age was 23 years (range 12-55 years) with 16 cases after the second dose. A higher-than-expected number of cases were seen in males aged 12-19 and 20-29 years, with incidence rates of 3.72 and 0.98 case per 100,000 doses, respectively.
CONCLUSION
Data from the national registry in Singapore indicate an increased incidence of pericarditis and myocarditis in younger men after COVID-19 mRNA vaccination.
Adolescent
;
Adult
;
COVID-19/prevention & control*
;
COVID-19 Vaccines/adverse effects*
;
Child
;
Female
;
Humans
;
Male
;
Middle Aged
;
Myocarditis/etiology*
;
Pericarditis/etiology*
;
RNA, Messenger
;
SARS-CoV-2
;
Vaccination/adverse effects*
;
Vaccines, Synthetic
;
Young Adult
;
mRNA Vaccines