Hookworm disease is one of the tropical neglected diseases that significantly impacts human health to varying degrees. Hookworms produce various proteins to facilitate host invasion and immune evasion. Despite available treatments, reinfection is common, underscoring the need for effective vaccines. However, the complexity of the hookworm's life cycle poses a challenge in understanding the immune response in the vaccine candidates. Reverse vaccinology (RV) offers a powerful approach to understand the immune response by using various bioinformatics tools. This study begins by identifying hookworm antigens capable of inducing host immune responses, followed by docking analysis with different dendritic cell (DC) receptors to investigate the immunological response of antigenic peptides and further correlated to the immunogenicity findings in clinical trial. Necator americanus GlutathioneS-Transferase-1 (Na-GST-1), a known immunogenic protein from Necator americanus, was selected for docking due to its strong antigenic properties. Fifteen DC receptors were evaluated against Na-GST-1, of which seven receptors (TLR2, TLR3, TLR4, TLR7, DEC-205, CD206, and CD36) exhibited stronger predicted interactions, as indicated by stronger binding affinities with Na-GST-1 utilizing various immunoinformatic tools. These receptors are associated with the mediation of Th1/Th2 immune responses, suggesting a potential correlation between docking affinity and the predicted immunogenicity of Na-GST-1. Overall, this study provides valuable insights into DC receptor-antigen interactions and demonstrate a computational approach for assessing the potential of hookworm antigens to engage DC receptors, thereby supporting rational hookworm vaccine design. These findings support the application of early in silico strategies for advancing vaccine candidates against hookworm infection and strengthening control efforts for neglected tropical diseases.

Blastocystis sp. is the most common enteric protist colonizing a wide range of host and is characterized by wide genotypic diversity. Heat Shock Protein 70 (HSP70), a common stress-response protein has been associated with increased proliferation in Blastocystis sp. under thermal stress. However, the extent of HSP70 genetic variation and its link to thermostability remains unexplored. Our study aims to elucidate HSP70 gene variants among different Blastocystis sp. subtypes, analyze their responses to thermal stress, and evaluate their protease activity following the thermal stress. Heat Shock Protein 70 gene from eighteen Blastocystis sp. isolates of varying subtype - ST1, ST3, ST4, ST6, and ST7 - were amplified, sequenced and phylogenetically analyzed. The cells were then subjected to thermal stress at 42°C for 24 hours and the cell viability was monitored for seven days. Protease activity in solubilized antigens (SA) from purified Blastocystis sp. cells was evaluated following exposure to thermal stress. Phylogenetic analysis revealed two distinct clades: ST4 and ST7 (Clade 1) which are mostly thermotolerant, while ST1, ST3, and ST6 (Clade 2) exhibited lower tolerance. Total protease activity was similar across subtypes, suggesting need for further sub-class specific analysis. Our findings suggests that thermal stress adaptation is subtype dependent and may be influenced by HSP70 variation. This insight highlights the importance of HSP70 as a potential molecular marker for stress adaptation in Blastocystis sp. and underscore the need for deeper investigation of its functional role in parasite persistence and pathogenic potential.

Scrub typhus, a zoonotic bacterial infection caused by the arthropod-borne, Gram-negative, obligate intracellular bacillus Orientia tsutsugamushi and transmitted by larval chiggers, is an underdiagnosed cause of acute undifferentiated febrile illness. Its clinical spectrum ranges from a self-limited denguelike illness to rapidly progressive multiorgan dysfunction driven by smallvessel vasculitis, including pneumonitis, acute kidney injury, hepatitis, encephalitis and circulatory shock. Early recognition is frequently missed because the characteristic eschar may be absent or easily overlooked in concealed or pigmented skin sites, and definitive diagnostics such as polymerase chain reaction (PCR) or indirect immunofluorescence assay (IFA) are often unavailable in resource-limited settings. Occupational and environmental exposures, particularly work in oil palm or rubber plantations and contact with forest- estate ecozones, remain key epidemiological clues that may be under-elicited in routine clinical practice. We report a case series of four patients with confirmed scrub typhus presenting to a hospital in Kluang district, Johor, Malaysia. All patients had acute fever and non-specific viral-like symptoms, including malaise, chills, headache and myalgia. Thrombocytopenia and acute kidney injury occurred in 50%, while 75% demonstrated transaminitis. Eschars were identified in all patients following comprehensive dermatological examination. Diagnosis was confirmed by PCR for O. tsutsugamushi DNA, a fourfold rise in IFA titres, or a single high-titre IgM or IgG in a compatible clinical syndrome. Three patients (75%) had clear domiciliary or occupational risk factors, including oil palm work or residence near secondary scrubland. One patient developed organ-threatening complications with acute kidney injury and severe hepatitis, illustrating the vasculitic end-organ involvement of severe scrub typhus. All patients achieved clinical defervescence and symptomatic improvement within 24-48 hours of doxycycline initiation, consistent with the characteristic brisk antimicrobial response. This series underscores the need for a low threshold of clinical suspicion and early empiric rickettsial coverage in undifferentiated febrile illness with relevant exposure in rural Malaysia and highlights the need for larger multicentre studies to define predictors of severity, guide triage and inform prevention in high-risk land-use settings.

Ovitrap surveillance of Aedes vectors in Sri Lanka needs improvement to effectively monitor vector abundance in dengue high-risk areas and detect emerging infestation zones. A study was conducted in two dengue high-risk areas, Narahenpita and Battaramulla in the Western Province, to assess the influence of ovistrip texture, color, and water type on Aedes oviposition, while adhering to WHO guidelines. The relationship of OI and the mean number of eggs per trap with ovitrap designs were determined by General Linear Model (GLM), which revealed a significant difference in the OI between the two study sites (P=0.005), while the mean number of eggs per ovitrap did not differ significantly (P=0.134). Water type had no significant influence on OI and mean number of eggs per ovitraps. A significant effect of ovistrip type (F=6.73, P<0.001) was found on OI and mean egg per trap (F=9.85, P<0.001), where filter paper exhibited the largest coefficient in magnitude (-0.1698), indicating a strong negative correlation with OI and mean eggs per trap (-2.445) while white fabric showed a strong positive co-efficient magnitude with OI (0.1108) and mean egg per trap (1.605). According to Spearman's rank correlation, the rainfall did not have a statistically significant effect on the number of eggs collected or the OI. The study suggested that fabric ovistrips colored white combined with rainwater or tap water, make ovitraps highly effective for Aedes vector surveillance, while the currently used filter paper ovistrip having a negative effect on the egg number laid.

Pediculosis capitis, caused by infestation of the human head louse Pediculus humanus capitis is endemic all over the world, and Malaysia is no exception. Permethrin is recommended as one of the first-line treatments for pediculosis capitis. However, after decades of intensive and continuous use, numerous treatment failures and recurrent cases have been reported globally due to established evidence of permethrin resistance. The fact that permethrin-based products are still widely used and available over the counter prompted this study to investigate the genotypic basis of permethrin resistance and to identify kdr alleles in head lice collected from seven children shelters located across Klang Valley, Malaysia. The PCR-RFLP employed in this study successfully demonstrated the kdr T917I mutation in head lice resulting in two genotypes: 31 (49.21%) homozygous susceptible (SS) and 32 (50.79%) heterozygous resistant (RS). These findings provide baseline data on permethrin resistance in Malaysia, which has not been previously investigated.

Coronavirus disease 2019 (COVID-19), which is caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has spread rapidly and caused a pandemic in 2020. Both pharmaceutical approaches, such as vaccinations and non-pharmaceutical approaches such as social distancing through lockdown and international border restrictions had been implemented to control the outbreak and the transmission of SARS-CoV-2. However, the prolonged implementation of these measures negatively impacted the population and global economy, while the continuously emerging SARS-CoV-2 variants led to breakthrough infections among the vaccinated populations. Given the ongoing nature of COVID-19, an efficient detection method for SARS-CoV-2 that could enable mass screening and on-site screening is needed to manage the disease and prevent further outbreaks at large scale. Hence, we have developed a tetra-combo LAMP SARS-CoV-2 detection assay that targets four SARS-CoV-2 genes (RdRp, S, E and N), with an internal control (RNaseP). The LAMP assay was validated using 370 RNA samples extracted from nasopharyngeal and/or oropharyngeal swabs. The LAMP assay developed in this study has on-par performance as the qRT-PCR assay, which is the gold standard method for SARS-CoV-2 detection, with a shorter turnaround time (25 minutes). The LAMP assay possessed 98.13% sensitivity, 100% specificity, 100% positive predictive value (PPV), and 95.45% negative predictive value (NPV) for samples with Ct values <= 35.

Chikungunya is a mosquito-borne viral disease caused by chikungunya virus (CHIKV), characterised by fever, polyarthralgia, myalgia, rash, and headache, with chronic arthralgia persisting for months or years. Although vaccine is recently available, it is not widely used, and treatment focuses on symptom relief. Many natural products or their active compounds have been investigated for their anti-CHIKV activities on Vero cells which is irrelevant in CHIKV pathogenesis in human. Tualang Honey has also been shown to exert anti-CHIKV in Vero cells. This study advances the evaluation of Tualang honey's antiviral activity against CHIKV by utilising human fibroblast-like synoviocyte (HFLS) cells, a model more reflective of joint pathology in chronic infection. The maximum non-toxic dose (MNTD) of honey was determined using XTT assay. The effects of different concentrations and incubation times of honey were explored using pre-treatment and post-treatment assays, while anti-adsorption and anti-entry assays were used to investigate its antiviral activities. The MNTD of Tualang honey on HFLS cells was determined to be 50 mg/mL. Tualang honey at concentrations < 20 mg/mL exhibited variable prophylactic activity in the pre-treatment assay, reducing viral titres by 29.21% to 94.87%. Significant CHIKV inhibition (p < 0.05) was observed with 10 and 15 mg/mL pre-treatment for 6 and 12 hours before infection, respectively. Notably, its anti-CHIKV effects were stronger during pre-treatment than post-treatment assay. Posttreatment with honey caused minimal to strong CHIKV inhibition, lowering viral titres by 6.67%-72.46%, depending on the concentration and incubation time, although it was not statistically significant. Tualang honey showed stronger anti-entry than anti-adsorption effects, decreasing viral titres by up to 90.45% and 66.89%, respectively. This study highlights Tualang honey's anti-CHIKV activity through various mechanisms, although further research is needed to confirm its clinical relevance. Importantly, the effects of concentration and incubation time are essential factors in determining antiviral efficacy.

Tuberculosis (TB) is one of the top 10 causes of death and the leading cause of morbidity from a single infectious agent. Tuberculous meningitis (TBM) is a subtype of tuberculosis which constitutes about 5% of all extrapulmonary tuberculosis and about 1-2% of active tuberculosis. This study was conducted to analyse the annual incidence of TBM in Malaysia from 2015-2020. Through this study we were also able to study the demographic characteristics and clinical profiles of TBM patients. It was a cross sectional study using data collected from Malaysia national case-based TB registry (MyTB) between year 2015 and 2020. Descriptive analysis was used and univariate analysis was performed using binary logistic regression. All the statistical analyses with p-value less than 0.05 is considered significant with the 95% confidence interval. There were total of 2072 TBM cases from year 2015 until 2020, which comprised of 1.38% of total TB cases within 6 years. Most of the patients were Malaysian (1682 cases (81.2%)) while only 390 (18.8%) cases were reported among foreigners. Most cases were detected among the age group of 35-44 with average of 77.8 (22.5%) cases per year, followed by age group 35-44 with average of 66.8 (19.35%) cases per year. Of all the TBM cases, 23.2% patients were known case of HIV while 1.45% diagnosed as HIV later. TBM is a disease with poor prognosis as the consequence of the half of the affected patient is death or severe disability which is evidenced by 42.7% patients passed away. TBM imposes a great challenge in both diagnosis and management, as most affected patients will be left with severe long-term complications even with treatment. It is important to understand the epidemiology and characteristics of tuberculous meningitis in Malaysia to improve the management and enhance the control of this deadly disease.

Cover & Contents Page 236 – 241 Pre- and post-COVID-19 pandemic evaluation of soil-transmitted helminth infections among the Kensiu Negrito indigenous community https://doi.org/10.47665/tb.42.3.001 242 – 249 Vernonia amygdalina (Delile) exhibits […]

Blastocystis is a ubiquitous intestinal protist of humans and animals. It is a genetically diverse organism whose part in the health and disease is still uncertain. This study provides information on Blastocystis STs in cattle, goats, and sheep in Perak, Malaysia, and the likely role of livestock animals in Blastocystis transmission to humans in Malaysia. Faecal samples from a total of 151 livestock animals consisting of cattle, goats, and sheep from Perak were examined by PCR analysis of the barcode region. Blastocystis ST10, ST14, and ST21 were identified in this study, and ST10 was common to all three ruminant livestock animal groups involved. Findings from previously published studies on Blastocystis in ruminant and non-ruminant livestock animals in Malaysia support indications that livestock animals may serve as reservoirs of human infections, being as one or more of the following Blastocystis subtypes: ST1, ST2, ST3, ST4, ST5, and ST6, have been isolated from both humans and livestock animals within similar regions of the country. Animal handlers are, therefore, advised to exercise proper hygiene to prevent possible transmission of Blastocystis from their animals, while further studies on the genetic variants of Blastocystis in farm animals and their keepers are required to better understand the role of these animals in human Blastocystis.