1.Drug resistance mutations among virological failure HIV-1 infected patients in Malaysia
Mohd Zain, R. ; Ibrahim, N. ; Ismail, S. ; Mat-Rahim, N.A. ; Suppiah, J. ; Thayan, R. ; , Z.
Tropical Biomedicine 2016;33(3):486-493
The determination of HIV drug resistance mutations (DRMs) towards antiretroviral
(ARV) drugs among HIV-1 treated patients with virological failure is crucial for further
management of the patient. This study aimed to assess the most common genomic mutation
and to analyse subtypes among the HIV-1 patients with viral load level > 1,000 copies/mL. A
total of 101 virological failure HIV-1 patients from four different regions of Peninsular Malaysia
with a viral load measurement facility were included in the study. Majority of patients (89.1%)
have at least 1 mutation associated with clinical resistance to either protease inhibitors
(PIs), nucleoside reverse transcriptase inhibitors (NRTIs) or nonnucleoside reverse
transcriptase inhibitors (NNRTIs). Major resistance mutations among the patients towards
NRTIs and NNRTIs were 70.3% and 18.8%, respectively. The most common mutation for
NRTIs was M184V while K103N mutation was detected in the majority of patients who were
treated with NNRTIs. The most commonly observed mutations for major PI and minor PI seen
among the study population were V82A/T and L10V, respectively. In HIV-1 subtype analysis,
CRF33_01B was the most predominant HIV-1 subtype in this study group. The vast detection
of DRMs in this study emphasized the importance of genotypic resistance test in the
management of HIV patients as DRMs can alter patient’s susceptibility towards ARV drugs.
Further study on larger number of samples is essential for the development of a database on
HIV-1 DRMs among patients that experience virological failure in Malaysia.
2.HIV-2 Infection in Malaysia: Current situation and the use of in-house real-time reverse transcription PCR for HIV-2
Mohd Zain, R. ; Ismail, S. ; Ellan, E.K. ; Wan Mahmood, N.A.N. ; Md Kassim, F. ; Thayan, R.
Tropical Biomedicine 2018;35(3):769-774
HIV-2 surveillance has been carried out in Malaysia for more than 25 years ago.
Tests to discriminate HIV-1 and HIV-2 are available but the options of test are limited and the
need to develop a new in-house HIV-2 real-time reverse transcription PCR (RT-PCR) is crucial.
A study was done on 29 samples from hospitals in Malaysia which were found to be positive
screening for HIV-2 antibodies by the commercial Western Blot assay. These samples were
further tested by a Western Blot assay that detects specific antibodies to HIV-2. Detection of
HIV-2 genome was then performed by using a commercial kit. Fifteen samples were evaluated
by using in-house real-time RT-PCR for HIV-2. Ninety-three percent (27/29) of samples have
positive results for HIV-2 on HIV-2 Western Blot with only 2 samples showing indeterminate
results. All samples showed negative results for HIV-2 genomes by using a PCR commercial
kit and the 15 samples that were subjected to our in-house real-time RT-HIV-2 PCR were also
tested negative for HIV-2 RNA. Results of HIV-2 Western Blot did not reflect the actual
positivity as both HIV-1 and HIV-2 antibodies may cross-react with either viral proteins. None
of the samples was confirmed positive for HIV-2 by the commercial and in-house real-time RTPCR.
In-house real-time RT-HIV-2 PCR assay can be further used to confirm the presence of
HIV-2 genome. Up to the year 2015, Malaysia is still free from HIV-2 infection.
3.Entamoeba infections and associated risk factors among migrant workers in Peninsular Malaysia
Sahimin, N. ; Yunus, M.H. ; Douadi, B. ; Yvonne Lim, A.L. ; Noordin, R. ; Behnke, J.M. ; Mohd Zain, S.N.
Tropical Biomedicine 2019;36(4):1014-1026
The influx of low skilled migrant workers to Malaysia from low socio-economic
countries where gastrointestinal parasitic infections are prevalent has raised concerns about
transmission to the local population. Three methods for detection (serology, microscopy and
molecular techniques) were utilized to identify Entamoeba infections amongst the targeted
cohort and determine risk factors associated with infection. Serological screening of 484
migrant workers from five working sectors in Peninsular Malaysia using IgG4 ELISA based on
the rPPDK antigen showed an overall seroprevalence of 7.4% (n = 36; CL95 = 5.3–10.1%) with
only one factor statistically associated with seropositivity of anti-amoebic antibodies, i.e.
years of residence in Malaysia (χ2
1 = 4.007, p = 0.045). Microscopic examination of 388 faecal
samples for protozoan cysts and trophozoites showed a slightly higher prevalence (11.6%;
n=45; CL95: 8.4–14.8%). Meanwhile, amplification of the 16S rDNA gene detected two species
i.e. Entamoeba dispar (23/388; 5.9%; CL95: 3.6–8.3%) and E. histolytica (11/388; 2.8%; CL95:
1.2–4.5%) and mixed infections with both parasites in only three samples (3/388; 0.8%; CL95:
0.2–2.2%). Entamoeba dispar infection was significantly associated with those employed in
food and domestic services (χ2
4 = 12.879, p = 0.012). However, none of the factors affected
the prevalence of E. histolytica infection. Despite the low prevalence of E. histolytica in
faecal samples of the study cohort, the presence of this pathogenic parasite still poses
potential public health risks and calls for tighter control strategies based on better availability
of chemotherapeutic treatment and accessibility to appropriate health education.