Insights into the Microbiome and Antibiotic Resistance Genes from Hospital Environmental Surfaces: A Prime Source of Antimicrobial Resistance.

Hospital environmental surfaces are potential reservoirs for transmitting hospital-associated pathogens. This study aimed to profile microbiomes and antibiotic resistance genes (ARGs) from hospital environmental surfaces using 16S rRNA amplicon and metagenomic sequencing at a tertiary teaching hospital in Malaysia. Samples were collected from patient sinks and healthcare staff counters at surgery and orthopaedic wards. The samples' DNA were subjected to 16S rRNA amplicon and shotgun sequencing to identify bacterial taxonomic profiles, antibiotic resistance genes, and virulence factor pathways. The bacterial richness was more diverse in the samples collected from patient sinks than those collected from staff counters. Proteobacteria and Verrucomicrobia dominated at the phylum level, while Bacillus, Staphylococcus, Pseudomonas, and Acinetobacter dominated at the genus level. Staphylococcus epidermidis and Staphylococcus aureus were prevalent on sinks while Bacillus cereus dominated the counter samples. The highest counts of ARGs to beta-lactam were detected, followed by ARGs against fosfomycin and cephalosporin. We report the detection of mcr-10.1 that confers resistance to colistin at a hospital setting in Malaysia. The virulence gene pathways that aid in antibiotic resistance gene transfer between bacteria were identified. Environmental surfaces serve as potential reservoirs for nosocomial infections and require mitigation strategies to control the spread of antibiotic resistance bacteria.

Recent advances in single-cell engineered live biotherapeutic products research for skin repair and disease treatment.

The human microbiome has emerged as a key player in maintaining skin health, and dysbiosis has been linked to various skin disorders. Amidst growing concerns regarding the side effects of antibiotic treatments, the potential of live biotherapeutic products (LBPs) in restoring a healthy microbiome has garnered significant attention. This review aims to evaluate the current state of the art of the genetically or metabolically engineered LBPs, termed single-cell engineered LBPs (eLBPs), for skin repair and disease treatment. While some studies demonstrate promising outcomes, the translation of eLBPs into clinical applications remains a significant hurdle. Substantial concerns arise regarding the practical implementation and scalability of eLBPs, despite the evident potential they hold in targeting specific cells and delivering therapeutic agents. This review underscores the need for further research, robust clinical trials, and the exploration of current advances in eLBP-based bioengineered bacterial chassis and new outlooks to substantiate the viability and effectiveness of eLBPs as a transformative approach in skin repair and disease intervention.

Epidemiology of multidrug-resistant Klebsiella pneumoniae infection in clinical setting in South-Eastern Asia: a systematic review and meta-analysis.

The rising prevalence of multidrug-resistant (MDR) and extended-spectrum beta lactamase-resistant (ESBL) Klebsiella pneumoniae (K. pneumoniae) is an important global public health challenge. This threat is even more pertinent in clinical settings. Morbidity and mortality associated with this condition are alarming particularly in the developing regions of the world. A comprehensive evaluation of the epidemiology of this phenomenon will assist towards the global effort of reducing its burden. So, this systematic review and meta-analysis was conducted to evaluate the epidemiology of MDR K. pneumoniae in South-Eastern Asia (SEA). The study was done under the PRISMA guidelines and was preceded by the development of a priori protocol. The protocol was then registered in PROSPERO-the public registry for systematic reviews. Seven important outcomes which include the assessment of the overall MDR K. pneumoniae prevalence were designed to be evaluated. A literature search was carried out in five selected electronic databases and 4389 were screened. Of these articles, 21 studies that met the eligibility criteria were included in the review. Relevant data were extracted from the included studies. By conducting a quality effect meta-analysis, the pooled prevalence for MDR and ESBL K. pneumoniae in SEA was estimated at 55% (CI 9-96) and 27% (CI 32-100) respectively. The review also identified ESBL genes types of allodemic situations occurring mostly in respiratory tract infections. The high prevalence of MDR and ESBL K. pneumoniae in this subregion is highly significant and of both public health and clinical relevance. Overall, the findings of this review will assist in the effective prevention and control of this threat in SEA.

Alpha-amyrin as an anti-biofilm agent against methicillin-resistant and vancomycin-intermediate Staphylococcus aureus.

Staphylococcus aureus has caused life-threatening infections and developed resistance against conventional antimicrobials, posing a significant threat to human health worldwide. Biofilms that surround the bacteria cells act as a protective layer, allowing cells inside the biofilm to be resistant to external stresses such as antimicrobials. Therefore, biofilms further complicate treatment available for infections caused by multi-drug resistant Staphylococcus aureus. A previous study on alpha-amyrin (AM), derived from ursane, was reported to significantly reduce the biomass and inhibit the metabolic activity of reference strain methicillin-resistant and methicillin-sensitive S. aureus (MRSA and MSSA, respectively). In this study, the antibiofilm activity of AM was extended to include clinical isolates of MSSA and MRSA, and laboratory-generated vancomycin-intermediate S. aureus (VISA) collected from University Kebangsaan Malaysia Medical Center (PPUKM) and Universiti Kebangsaan Malaysia Medical Molecular Biology Institute (UMBI). Pre-formed biofilms of biofilm-forming isolates identified from the Congo Red Agar (CRA) assay were then exposed to AM, vancomycin and oxacillin, and evaluated using the crystal violet and resazurin assays. The results showed that AM reduced the biofilm biomass of three isolates of MSSA, eight isolates of MRSA and four isolates of VISA but increased the metabolic activity in certain MSSA, MRSA and VISA isolates, indicating AM may possess biofilm reduction effects but not bactericidal effects. Based on these findings, AM could be further studied and developed as a potential therapeutic agent for chronic S. aureus infections.

Parvimonas micra infection enhances proliferation, wound healing, and inflammation of a colorectal cancer cell line.

The gut microbiota Parvimonas micra has been found to be enriched in gut mucosal tissues and fecal samples of colorectal cancer (CRC) patients compared with non-CRC controls. In the present study, we investigated the tumorigenic potential of P. micra and its regulatory pathways in CRC using HT-29, a low-grade CRC intestinal epithelial cell. For every P. micra-HT-29 interaction assay, HT-29 was co-cultured anaerobically with P. micra at an MOI of 100:1 (bacteria: cells) for 2 h. We found that P. micra increased HT-29 cell proliferation by 38.45% (P=0.008), with the highest wound healing rate at 24 h post-infection (P=0.02). In addition, inflammatory marker expression (IL-5, IL-8, CCL20, and CSF2) was also significantly induced. Shotgun proteomics profiling analysis revealed that P. micra affects the protein expression of HT-29 (157 up-regulated and 214 down-regulated proteins). Up-regulation of PSMB4 protein and its neighbouring subunits revealed association of the ubiquitin-proteasome pathway (UPP) in CRC carcinogenesis; whereas down-regulation of CUL1, YWHAH, and MCM3 signified cell cycle dysregulation. Moreover, 22 clinically relevant epithelial-mesenchymal transition (EMT)-markers were expressed in HT-29 infected with P. micra. Overall, the present study elucidated exacerbated oncogenic properties of P. micra in HT-29 via aberrant cell proliferation, enhanced wound healing, inflammation, up-regulation of UPPs, and activation of EMT pathways.

Diversity and Dissemination of Methicillin-Resistant Staphylococcus aureus (MRSA) Genotypes in Southeast Asia.

Methicillin-resistant Staphylococcus aureus (MRSA) is a successful pathogen that has achieved global dissemination, with high prevalence rates in Southeast Asia. A huge diversity of clones has been reported in this region, with MRSA ST239 being the most successful lineage. Nonetheless, description of MRSA genotypes circulating in the Southeast Asia region has, until now, remained poorly compiled. In this review, we aim to provide a better understanding of the molecular epidemiology and distribution of MRSA clones in 11 Southeast Asian countries: Singapore, Malaysia, Thailand, Vietnam, Cambodia, Lao People's Democratic Republic (PDR), Myanmar, Philippines, Indonesia, Brunei Darussalam, and Timor-Leste. Notably, while archaic multidrug-resistant hospital-associated (HA) MRSAs, such as the ST239-III and ST241-III, were prominent in the region during earlier observations, these were then largely replaced by the more antibiotic-susceptible community-acquired (CA) MRSAs, such as ST22-IV and PVL-positive ST30-IV, in recent years after the turn of the century. Nonetheless, reports of livestock-associated (LA) MRSAs remain few in the region.

Draft Genome Sequences of Four Methicillin-Resistant Staphylococcus aureus Strains (M080_2017, M106_2017, M181_2017, and M191_2017), Isolated from a Malaysian Teaching Hospital.

Draft genome sequences were obtained for four methicillin-resistant Staphylococcus aureus (MRSA) strains isolated from various wards of the Hospital Canselor Tuanku Muhriz (HCTM), Kuala Lumpur, Malaysia, in 2017. Using different bioinformatics tools, we annotated the draft genomes and identified multiple antimicrobial resistance genes.

Pathogens and Carcinogenesis: A Review.

Cancer is a global health problem associated with genetics and unhealthy lifestyles. Increasingly, pathogenic infections have also been identified as contributors to human cancer initiation and progression. Most pathogens (bacteria, viruses, fungi, and parasites) associated with human cancers are categorized as Group I human carcinogens by the International Agency for Research on Cancer, IARC. These pathogens cause carcinogenesis via three known mechanisms: persistent infection that cause inflammation and DNA damage, initiation of oncogene expression, and immunosuppression activity of the host. In this review, we discuss the carcinogenesis mechanism of ten pathogens, their implications, and some future considerations for better management of the disease. The pathogens and cancers described are Helicobacter pylori (gastric cancer), Epstein-Barr virus (gastric cancer and lymphoma), Hepatitis B and C viruses (liver cancer), Aspergillus spp. (liver cancer), Opisthorchis viverrine (bile duct cancer), Clonorchis sinensis (bile duct cancer), Fusobacterium nucleatum (colorectal cancer), Schistosoma haematobium (bladder cancer); Human Papillomavirus (cervical cancer), and Kaposi's Sarcoma Herpes Virus (Kaposi's sarcoma).

Comparison of sPLA2IIA performance with high-sensitive CRP neutrophil percentage PCT and lactate to identify bacterial infection.

Early bacterial infection (BI) identification in resource-limiting Emergency Departments (ED) is challenging, especially in low- and middle-income counties (LMIC). Misdiagnosis predisposes to antibiotic overuse and propagates antimicrobial resistance. This study evaluates new emerging biomarkers, secretory phospholipase A2 group IIA (sPLA2-IIA) and compares with other biomarkers on their performance characteristic of BI detection in Malaysia, an LMIC. A prospective cohort study was conducted involving 151 consecutive patients admitted to the ED. A single measurement was taken upon patient arrival in ED and was analysed for serum levels of sPLA2-IIA, high-sensitive C-reactive protein (CRP), procalcitonin (PCT), neutrophil percentage (N%), and lactate. All biomarkers' performance was compared for the outcomes using area under the receiver operating characteristic curve (AUROC), sensitivity, and specificity. The performance of sPLA2-IIA (AUROC 0.93 [95% CI: 0.89-0.97]; Sn 80% [95% CI: 72-87]; Sp 94% [95% CI: 81-89]) was the highest among all. It was comparable with high-sensitive CRP (AUROC 0.93 [95% CI: 0.88-0.97]; Sn 75% [95% CI: 66-83]; Sp 91 [95% CI: 77-98]) but had a higher Sn and Sp. The sPLA2-IIA was also found superior to N%, PCT, and lactate. This finding suggested sPLA2-IIA was recommended biomarkers for BI detection in LMIC.

Methicillin-Resistant Staphylococcus aureus (MRSA) Clonal Replacement in a Malaysian Teaching Hospital: Findings from an Eight-Year Interval Molecular Surveillance.

Periodical surveillance on nosocomial pathogens is important for antimicrobial stewardship and infection control. The first methicillin-resistant Staphylococcus aureus (MRSA) molecular surveillance in Hospital Canselor Tuanku Muhriz (HCTM), a Malaysian teaching hospital, was performed in 2009. The dominant clone was identified as an MRSA carrying SCCmec type III-SCCmercury with ccrC and sea+cna toxin genes. In this study, we report the findings of the second HCTM MRSA surveillance carried out in 2017, after an interval of 8 years. Antibiotic susceptibility testing, SCCmec, toxin gene, and spa typing were performed for 222 MRSA strains isolated in 2017. Most strains were resistant to ciprofloxacin, erythromycin, clindamycin, cefoxitin, and penicillin (n = 126, 56.8%), belong to SCCmec type IV (n = 205, 92.3%), spa type t032 (n = 160, 72.1%) and harboured seg+sei toxin genes (n = 172, 77.5%). There was significant association between resistance of the aforementioned antibiotics with SCCmec type IV (p < 0.05), t032 (p < 0.001), and seg+sei carriage (p < 0.05). Results from this second MRSA surveillance revealed the occurrence of clonal replacement in HCTM during an interval of not more than 8 years. Investigation of the corresponding phenotype changes in this new dominant MRSA clone is currently on-going.

Gut microbiota in Immunoglobulin A Nephropathy: a Malaysian Perspective.

INTRODUCTION: The alteration of the gut microbiome in the gut-kidney axis has been associated with a pro-inflammatory state and chronic kidney disease (CKD). A small-scaled Italian study has shown an association between the gut microbiome and Immunoglobulin A Nephropathy (IgAN). However, there is no data on gut microbiota in IgAN in the Asian population. This study compares the gut microbial abundance and diversity between healthy volunteers and Malaysian IgAN cohort. METHODS: A comparative cross-sectional study was conducted involving biopsy-proven IgAN patients in clinical remission with matched controls in a Malaysian tertiary centre. Demographic data, routine blood and urine results were recorded. Stool samples were collected and their DNA was extracted by 16S rRNA gene sequencing to profile their gut microbiota. RESULTS: Thirty-six IgAN patients (13 male; 23 female) with the mean age of 45.5 ± 13.4 years and median estimated glomerular filtration rate (eGFR) of 79.0 (62.1-92.2) mls/min/1.73m2 with median remission of 7 years were analysed and compared with 12 healthy controls (4 male; 8 female) with the mean age of 46.5 ± 13.5 years and eGFR of 86.5 (74.2-93.7) mls/min/1.73m2. Other demographic and laboratory parameters such as gender, ethnicity, body mass index (BMI), haemoglobin, serum urea and serum albumin were comparable between the two groups. There were no significant differences seen in the Operational Taxonomic Unit (OTU) and alpha diversity (Shannon index) between IgAN and healthy controls. Alpha diversity increased with increasing CKD stage (p = 0.025). Firmicutes/Bacteroidetes (F/B) ratio was low in both IgAN and healthy cohort. Fusobacteria phylum was significantly increased (p = 0.005) whereas Euryarchaoeota phylum was reduced (p = 0.016) in the IgAN group as compared to the control cohort. CONCLUSION: Although we found no differences in OTU and alpha diversity between IgAN in remission and control cohort, there were some differences between the two groups at phylum level.

Parvimonas micra, Peptostreptococcus stomatis, Fusobacterium nucleatum and Akkermansia muciniphila as a four-bacteria biomarker panel of colorectal cancer.

Dysbiosis of the gut microbiome has been associated with the pathogenesis of colorectal cancer (CRC). We profiled the microbiome of gut mucosal tissues from 18 CRC patients and 18 non-CRC controls of the UKM Medical Centre (UKMMC), Kuala Lumpur, Malaysia. The results were then validated using a species-specific quantitative PCR in 40 CRC and 20 non-CRC tissues samples from the UMBI-UKMMC Biobank. Parvimonas micra, Fusobacterium nucleatum, Peptostreptococcus stomatis and Akkermansia muciniphila were found to be over-represented in our CRC patients compared to non-CRC controls. These four bacteria markers distinguished CRC from controls (AUROC = 0.925) in our validation cohort. We identified bacteria species significantly associated (cut-off value of > 5 fold abundance) with various CRC demographics such as ethnicity, gender and CRC staging; however, due to small sample size of the discovery cohort, these results could not be further verified in our validation cohort. In summary, Parvimonas micra, Fusobacterium nucleatum, Peptostreptococcus stomatis and Akkermansia muciniphila were enriched in our local CRC patients. Nevertheless, the roles of these bacteria in CRC initiation and progression remains to be investigated.

The heterogeneic distribution of Helicobacter pylori cag pathogenicity island reflects different pathologies in multiracial Malaysian population

ABSTRACT Background: Helicobacter pylori harbouring cag-pathogenicity island (cagPAI) which encodes type IV secretion system (T4SS) and cagA virulence gene are involved in inflammation of the gastric mucosa. We examined all the 27 cagPAI genes in 88 H. pylori isolates from patients of different ethnicities and examined the association of the intactness of cagPAI region with histopathological scores of the gastric mucosa. Results: 96.6% (n = 85) of H. pylori isolates were cagPAI-positive with 22.4% (19/85) having an intact cagPAI, whereas 77.6% (66/85) had a partial/rearranged cagPAI. The frequency of cag2 and cag14 were found to be significantly higher in H. pylori isolated from Malays, whereas cag4 was predominantly found in Chinese isolates. The cag24 was significantly found in higher proportions in Malay and Indian isolates than in Chinese isolates. The intactness of cagPAI region showed an association with histopathological scores of the gastric mucosa. Significant association was observed between H. pylori harbouring partial cagPAI with higher density of bacteria and neutrophil activity, whereas strains lacking cagPAI were associated with higher inflammatory score. Conclusions: The genotypes of H. pylori strains with various cagPAI rearrangement associated with patients' ethnicities and histopathological scores might contribute to the pathogenesis of H. pylori infection in a multi-ethnic population.

The heterogeneic distribution of Helicobacter pylori cag pathogenicity island reflects different pathologies in multiracial Malaysian population.

BACKGROUND: Helicobacter pylori harbouring cag-pathogenicity island (cagPAI) which encodes type IV secretion system (T4SS) and cagA virulence gene are involved in inflammation of the gastric mucosa. We examined all the 27 cagPAI genes in 88 H. pylori isolates from patients of different ethnicities and examined the association of the intactness of cagPAI region with histopathological scores of the gastric mucosa. RESULTS: 96.6% (n=85) of H. pylori isolates were cagPAI-positive with 22.4% (19/85) having an intact cagPAI, whereas 77.6% (66/85) had a partial/rearranged cagPAI. The frequency of cag2 and cag14 were found to be significantly higher in H. pylori isolated from Malays, whereas cag4 was predominantly found in Chinese isolates. The cag24 was significantly found in higher proportions in Malay and Indian isolates than in Chinese isolates. The intactness of cagPAI region showed an association with histopathological scores of the gastric mucosa. Significant association was observed between H. pylori harbouring partial cagPAI with higher density of bacteria and neutrophil activity, whereas strains lacking cagPAI were associated with higher inflammatory score. CONCLUSIONS: The genotypes of H. pylori strains with various cagPAI rearrangement associated with patients' ethnicities and histopathological scores might contribute to the pathogenesis of H. pylori infection in a multi-ethnic population.

Advantages and Limitations of 16S rRNA Next-Generation Sequencing for Pathogen Identification in the Diagnostic Microbiology Laboratory: Perspectives from a Middle-Income Country.

Bacterial culture and biochemical testing (CBtest) have been the cornerstone of pathogen identification in the diagnostic microbiology laboratory. With the advent of Sanger sequencing and later, next-generation sequencing, 16S rRNA next-generation sequencing (16SNGS) has been proposed to be a plausible platform for this purpose. Nevertheless, usage of the 16SNGS platform has both advantages and limitations. In addition, transition from the traditional methods of CBtest to 16SNGS requires procurement of costly equipment, timely and sustainable maintenance of these platforms, specific facility infrastructure and technical expertise. All these factors pose a challenge for middle-income countries, more so for countries in the lower middle-income range. In this review, we describe the basis for CBtest and 16SNGS, and discuss the limitations, challenges, advantages and future potential of using 16SNGS for bacterial pathogen identification in diagnostic microbiology laboratories of middle-income countries.

Dengue epidemic in Malaysia: urban versus rural comparison of dengue immunoglobulin G seroprevalence among Malaysian adults aged 35-74 years.

BACKGROUND: A periodic serosurvey of dengue seroprevalence is vital to determine the prevalence of dengue in countries where this disease is endemic. This study aimed to determine the prevalence of dengue immunoglobulin G (IgG) seropositivity among healthy Malaysian adults living in urban and rural areas. METHODS: A total of 2598 serum samples (1417 urban samples, 1181 rural samples) were randomly collected from adults ages 35-74 y. The presence of the dengue IgG antibody and neutralising antibodies to dengue virus (DENV) 1-4 was determined using enzyme-linked immunosorbent assay and the plaque reduction neutralisation test assay, respectively. RESULTS: The prevalence of dengue IgG seropositivity was 85.39% in urban areas and 83.48% in rural areas. The seropositivity increased with every 10-y increase in age. Ethnicity was associated with dengue seropositivity in urban areas but not in rural areas. The factors associated with dengue seropositivity were sex and working outdoors. In dengue IgG-positive serum samples, 98.39% of the samples had neutralising antibodies against DENV3, but only 70.97% of them had neutralising antibodies against DENV4. CONCLUSION: The high seroprevalence of dengue found in urban and rural areas suggests that both urban and rural communities are vital for establishing and sustaining DENV transmission in Malaysia.

Molecular surveillance of methicillin-susceptible Staphylococcus aureus (MSSA) isolated over a one-year period from a Malaysian Teaching Hospital.

INTRODUCTION: We report the results of a molecular surveillance study carried out on methicillin-susceptible Staphylococcus aureus (MSSA) isolated in a one-year duration from Hospital Canselor Tuanku Muhriz (HCTM), a tertiary hospital located in Kuala Lumpur, Malaysia. METHODS: The first strain isolated from each MSSA infection in HCTM during the year 2009 was included into the study. Antimicrobial susceptibility testing and agr group typing were carried out for all strains; virulence gene (cna, seh, TSST-1 and PVL) typing results of the strains were obtained from a previous study. Pulsed-field gel electrophoresis (PFGE) was done on selected strains from the orthopedic ward. Relationship(s) between different typing methods used in the study was investigated, where a p value of <0.05 indicated significant association between typing methods. RESULTS: A total of 880 MSSA strains were included into the study. The strains were generally susceptible to most antibiotics, with most of them carrying cna and agr-I (51.6%, n=454; 39.8%, n=350, respectively). A total of 17 PFGE pulsotypes were identified using an 80% similarity cut-off value, where the main pulsotype (pulsotype E) consisted of 24 isolates (23.5%). agr-III strains were found to be usually positive for both cna and seh (p<0.05). In addition, some PFGE pulsotypes were also characteristic of certain virulence genes or agr groups. CONCLUSIONS: We did not identify a dominant MSSA clone circulating in HCTM in 2009. Nevertheless, results from this molecular surveillance will provide good baseline data for the hospital's second S. aureus surveillance planned for the year 2020.

Pulsed-field gel electrophoresis (PFGE): A review of the "gold standard" for bacteria typing and current alternatives.

Pulsed-field gel electrophoresis (PFGE) is considered the "gold standard" for bacteria typing. The method involves enzyme restriction of bacteria DNA, separation of the restricted DNA bands using a pulsed-field electrophoresis chamber, followed by clonal assignment of bacteria based on PFGE banding patterns. Various PFGE protocols have been developed for typing different bacteria, leading it to be one of the most widely used methods for phylogenetic studies, food safety surveillance, infection control and outbreak investigations. On the other hand, as PFGE is lengthy and labourious, several PCR-based typing methods can be used as alternatives for research purposes. Recently, matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF MS) and whole genome sequencing (WGS) have also been proposed for bacteria typing. In fact, as WGS provides more information, such as antimicrobial resistance and virulence of the tested bacteria in comparison to PFGE, more and more laboratories are currently transitioning from PFGE to WGS for bacteria typing. Nevertheless, PFGE will remain an affordable and relevant technique for small laboratories and hospitals in years to come.

Oxidative stress resistance and fitness-compensatory response in vancomycin-intermediate Staphylococcus aureus (VISA).

In this study, vancomycin-intermediate Staphylococcus aureus (VISA) cells carrying vraS and (or) graR mutations were shown to be more resistant to oxidative stress. Caenorhabditis elegans infected with these strains in turn demonstrated lower survival. Altered regulation in oxidative stress response and virulence appear to be physiological adaptations associated with the VISA phenotype in the Mu50 lineage.

Establishment of an immunofluorescence assay to detect IgM antibodies to Nipah virus using HeLa cells expressing recombinant nucleoprotein.

A novel indirect fluorescent antibody test (IFAT) for detection of IgM against Nipah virus (NiV) was developed using HeLa 229 cells expressing recombinant NiV nucleocapsid protein (NiV-N). The NiV IFAT was evaluated using three panels of sera: a) experimentally produced sera from NiV-N-immunized/pre-immunized macaques, b) post-infection human sera associated with a Nipah disease outbreak in the Philippines in 2014, and c) human sera from a non-exposed Malaysian population. Immunized macaque sera showed a characteristic granular staining pattern of the NiV-N expressed antigen in HeLa 229 cells, which was readily distinguished from negative-binding results of the pre-immunized macaque sera. The IgM antibody titers in sequential serum samples (n = 7) obtained from three Nipah patients correlated well with previously published results using conventional IgM capture ELISA and SNT serology. The 90 human serum samples from unexposed persons were unreactive by IFAT. The IFAT utilizing NiV-N-expressing HeLa 229 cells to detect IgM antibody in an early stage of NiV infection is an effective approach, which could be utilized readily in local laboratories to complement other capabilities in NiV-affected countries.