MERS-CoV seroconversion amongst Malaysian Hajj pilgrims returning from the Middle East, 2016-2018: results from the MERCURIAL multiyear prospective cohort study.

Prospective cohort study to investigate the potential exposure to the Middle East Respiratory Syndrome-Coronavirus (MERS-CoV) following Hajj pilgrims is still very limited. Here, we report the antibody seroconversion study results obtained from successive three years cohort studies (2016-2018) involving the Malaysian Hajj pilgrims returning from the Middle East. A cohort study of Hajj pilgrims from Malaysia enrolled 2,863 participants from 2016-2018, all of whom consented to provide paired blood samples for both pre- and post-Hajj travel to the Middle East. ELISAs and micro-neutralization assays were performed to detect the presence of MERS-CoV IgG antibodies. Sociodemographic data, symptoms experienced during Hajj, and history of exposure to camels or camel products were recorded using structured pre- and post-Hajj questionnaires. A 4-fold increase in anti-MERS-CoV IgG between paired pre-Hajj and post-Hajj serum samples in twelve participants was observed. None of the twelve ELISA-positive sera had detectable levels of virus-neutralizing antibodies. All reportedly had mild symptoms of respiratory symptoms at a certain point during the pilgrimage, implying mild or asymptomatic infections. No association between post-Hajj serum positivity and a history of exposure to camels or camel products was obtained. Findings from the study suggest that serologic conversion to MERS-CoV occurred in at least 0.6% of the Hajj pilgrims returning from the Middle East. Since all the seroconvertants had mild to no symptoms during the sampling period, it highlights the likelihood of occurrence of only low infectivity spillover infections among the Hajj pilgrims.

Multiyear prospective cohort study to evaluate the risk potential of MERS-CoV infection among Malaysian Hajj pilgrims (MERCURIAL): a study protocol.

INTRODUCTION: Middle East respiratory syndrome (MERS) is a viral respiratory infection caused by the MERS-CoV. MERS was first reported in the Kingdom of Saudi Arabia in 2012. Every year, the Hajj pilgrimage to Mecca attracts more than two million pilgrims from 184 countries, making it one of the largest annual religious mass gatherings (MGs) worldwide. MGs in confined areas with a high number of pilgrims' movements worldwide continues to elicit significant global public health concerns. MERCURIAL was designed by adopting a seroconversion surveillance approach to provide multiyear evidence of MG-associated MERS-CoV seroconversion among the Malaysian Hajj pilgrims. METHODS AND ANALYSIS: MERCURIAL is an ongoing multiyear prospective cohort study. Every year, for the next 5 years, a cohort of 1000 Hajj pilgrims was enrolled beginning in the 2016 Hajj pilgrimage season. Pre-Hajj and post-Hajj serum samples were obtained and serologically analysed for evidence of MERS-CoV seroconversion. Sociodemographic data, underlying medical conditions, symptoms experienced during Hajj pilgrimage, and exposure to camel and untreated camel products were recorded using structured pre-Hajj and post-Hajj questionnaires. The possible risk factors associated with the seroconversion data were analysed using univariate and multivariate logistic regression. The primary outcome of this study is to better enhance our understanding of the potential threat of MERS-CoV spreading through MG beyond the Middle East. ETHICS AND DISSEMINATION: This study has obtained ethical approval from the Medical Research and Ethics Committee (MREC), Ministry of Health Malaysia. Results from the study will be submitted for publication in peer-reviewed journals and presented in conferences and scientific meetings. TRIAL REGISTRATION NUMBER: NMRR-15-1640-25391.

Genetic mechanisms and correlated risk factors of antimicrobial-resistant ESKAPEE pathogens isolated in a tertiary hospital in Malaysia.

BACKGROUND: Knowledge on the epidemiology, genotypic and phenotypic features of antimicrobial-resistant (AMR) ESKAPEE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, Enterobacter spp., and Escherichia coli) and their association with hospital-acquired infections (HAIs) are limited in Malaysia. Therefore, we evaluated the AMR features and resistance mechanisms of the ESKAPEE pathogens collected in a tertiary hospital located in the capital of Malaysia. METHODS: A total of 378 AMR-ESKAPEE strains were obtained based on convenience sampling over a nine-month study period (2019-2020). All strains were subjected to disk diffusion and broth microdilution assays to determine the antimicrobial susceptibility profiles. Polymerase chain reaction (PCR) and DNA sequence analyses were performed to determine the AMR genes profiles of the non-susceptible strains. Chi-square test and logistic regression analyses were used to correlate the AMR profiles and clinical data to determine the risk factors associated with HAIs. RESULTS: High rates of multidrug resistance (MDR) were observed in A. baumannii, K. pneumoniae, E. coli, and S. aureus (69-89%). All organisms except E. coli were frequently associated with HAIs (61-94%). Non-susceptibility to the last-resort drugs vancomycin (in Enterococcus spp. and S. aureus), carbapenems (in A. baumannii, P. aeruginosa, and Enterobacteriaceae), and colistin (in Enterobacteriaceae) were observed. Both A. baumannii and K. pneumoniae harbored a wide array of extended-spectrum ß-lactamase genes (blaTEM, blaSHV, blaCTX-M, blaOXA). Metallo-ß-lactamase genes (blaVEB, blaVIM, blaNDM) were detected in carbapenem-resistant strains, at a higher frequency compared to other local reports. We detected two novel mutations in the quinolone-resistant determining region of the gyrA in fluoroquinolone-resistant E. coli (Leu-102-Ala; Gly-105-Val). Microbial resistance to ampicillin, methicillin, and cephalosporins was identified as important risk factors associated with HAIs in the hospital. CONCLUSION: Overall, our findings may provide valuable insight into the microbial resistance pattern and the risk factors of ESKAPEE-associated HAIs in a tertiary hospital located in central Peninsular Malaysia. The data obtained in this study may contribute to informing better hospital infection control in this region.

High Prevalence of Viral Infections Among Hospitalized Pneumonia Patients in Equatorial Sarawak, Malaysia.

BACKGROUND: Although pneumonia is a known cause of morbidity and mortality in Sarawak, Malaysia, the etiology and epidemiology of pneumonia are not well described in this equatorial region. Routine clinical diagnostics for pneumonia etiology at government hospitals in Sarawak had historically involved only bacterial diagnostics. Viral diagnostics were only obtained through outside consultations. METHODS: From June 15, 2017 to May 14, 2018, we collected nasopharyngeal swabs from 600 patients of all ages older than 1 month hospitalized with pneumonia at Sibu and Kapit Hospitals. Specimens were examined at our collaborating institutions with a panel of molecular assays for viral pathogens including influenza A (IAV), IBV, ICV, and IDV, human adenovirus (AdV), human enterovirus (EV), human coronavirus (CoV), respiratory syncytial virus subtype A (RSV-A) or RSV-B, and parainfluenza virus (PIV) types 1-4. RESULTS: Of 599 samples examined, 288 (48%) had molecular evidence of 1 or more respiratory viruses. Overall, the most prevalent virus detected was RSV-A (14.2%) followed by AdV (10.4%) and IAV (10.4%), then RSV-B (6.2%), EV (4.2%), IBV (2.2%), PIV-3 (1.7%), CoV (1.0%), PIV-1 (1.0%), PIV-4 (0.7%), and PIV-2 (0.2%). No specimens were confirmed positive for ICV or IDV. CONCLUSIONS: The high prevalence of viruses detected in this study suggest that respiratory viruses may be responsible for considerable morbidity in equatorial regions such as Sarawak. Access to viral diagnostics are very necessary for medical staff to determine appropriate pneumonia treatments.

Rotavirus genotypes associated with acute diarrhea in Egyptian infants.

BACKGROUND: Before the introduction of rotavirus vaccine in Egypt, information on the burden of disease and the circulating rotavirus genotypes is critical to monitor vaccine effectiveness. METHODS: A cohort of 348 Egyptian children was followed from birth to 2 years of age with twice-weekly home visits to detect diarrheal illness. VP7 and VP4 genes were genotyped by reverse-transcription polymerase chain reaction and DNA sequencing. RESULTS: Forty percentage of children had rotavirus-associated diarrhea at least once by their second birthday. One hundred and twelve children experienced a single rotavirus diarrheal episodes (RDE) at a median age of 9 months; while 27 infants had their second RDE at a median age of 15 months and 1 infant had 3 RDE at the age of 2, 16 and 22 months. Of the 169 RDE, 82% could be assigned a G-type, while 58% had been identified a P-type. The most prevalent genotype was G2 (32%), followed by G1 (24%) and G9 (19%). G2P[4] rotavirus episodes were significantly associated with fever (P = 0.03) and vomiting (P = 0.06) when compared with other genotypes. G2 strains were the predominant genotype causing 50% of the second RDE while G9 represented 25% of the second RDE. CONCLUSIONS: Genotypes identified are similar to those detected globally except for absence of G4. Our finding that 75% of the second RDE were due to G2 and G9 indicates a possible reduction in natural protection afforded by these types compared with G1, where 90% of G1 cases did not experience a second xposure, indicating greater protection against recurrent symptomatic infection.

Genetic characterization of antimicrobial resistance of Shigella flexneri 1c isolates from patients in Egypt and Pakistan.

BACKGROUND: Shigella flexneri serotype 1c emerged as a critical isolate from children in Egypt and Pakistan. The pattern of antimicrobial susceptibility (AMS) and resistance genes of this serotype have yet to be characterized. FINDINGS: Sixty nine S. flexneri 1c isolates isolates were identified from both Egypt (n-46) and Pakistan (n = 23) and tested for AMS by disk diffusion method and minimal inhibitory concentrations were also determined. Isolates were genotyped by pulsed field gel electrophoresis (PFGE) and five relevant resistance genes (bla(TEM), bla(SHV), bla(OXA), sulI and sulII) were detected by polymerase chain reaction (PCR) and confirmed by DNA sequencing. High resistance was observed in all isolates for ampicillin (AM >96%); trimethoprim-sulphamethoxazole and tetracycline (>88%). Most AM-resistant isolates from Egypt (70%) harbored bla(TEM) resistance, while 52% of isolates from Pakistan expressed bla(OXA). All isolates were closely related by PFGE, irrespective of source or time of collection. The sulII gene was present in 100% of isolates from pediatric cases in Egypt, 65% of Pakistan isolates, and 53% of isolates from older Egyptian patients. CONCLUSIONS: While different Shigella serotypes gathered in specific genotypic groups, 1c serotype isolates formed multiple clusters. Although AMS was considerably high to most commonly used drugs, genetic determinants were variable between countries over time. The data stress the need for a more careful selection of antibiotics in the treatment of shigellosis.

Characterization of human rotaviruses circulating in Iraq in 2008: atypical G8 and high prevalence of P[6] strains.

Fecal samples from 976 children with gastroenteritis were collected and analyzed for group A rotavirus (RVA), in three different cities in Iraq between January 2008 and December 2008. RVA antigen was detected in 394 (40%) of the samples, and 98 samples were available for further genotype analyses using multiplex RT-PCR and sequence analyses for untypeable strains. The G/P-genotype combination was determined for 69 samples, and 19, 2 and 8 samples remained P-untypeable, G-untypeable and G/P-untypeable (UT), respectively. The most prevalent genotype was G2 (40%, 39/98) most often associated with P[6]. G1 was the second most common genotype (16%, 16/98) mainly associated with P[8] and P[UT]. G3, G4 and G9 were detected at a lower prevalence (3%, 11%, 3%, respectively), mainly associated with P[6]. Surprisingly, five G8P[6], and seven G12 RVA strains in combination with P[6] and P[8] were also detected for the first time in Iraq. Overall, a striking high prevalence of 47% of the analyzed samples possessed the P[6] genotype (65% of the P-typed RVA strains). Atypical genotype combinations such as G1P[4], G1P[6], G2P[8] or strains with mixed G-types were detected sporadically. The detection of unusual G8P[6] RVA strains prompted us to further analyze the NSP2, NSP3, NSP4 and NSP5 gene segments of three selected G8P[6] strains, resulting in their designation to the N2, T2, E2 and H2 genotypes, respectively. The VP7, VP4, NSP2, NSP3 and NSP5 gene segments clustered closely with common human RVA strains, whereas the NSP4 gene sequences were found to cluster with animal derived RVA strains, suggesting a potential reassortment event. The high prevalence of RVA strains with the G8, G12 and P[6] genotypes in combination with a DS-1-like genotype constellation in Iraq, needs to be monitored closely as these RVA strains might challenge the effectiveness of current RVA vaccines.

Development of a murine hematopoietic progenitor complementary DNA microarray using a subtracted complementary DNA library.

With the goal of creating a resource for in-depth study of myelopoiesis, we have executed a 2-pronged strategy to obtain a complementary DNA (cDNA) clone set enriched in hematopoietic genes. One aspect is a library subtraction to enrich for underrepresented transcripts present at early stages of hematopoiesis. For this, a hematopoietic cDNA library from primary murine bone marrow cells enriched for primitive progenitors was used as tester. The subtraction used 10 000 known genes and expressed sequence tags (ESTs) as driver. The 2304 randomly picked clones from the subtracted cDNA libraries represent 1255 distinct genes, of which 622 (50%) are named genes, 386 (30%) match uncharacterized ESTs, and 247 (20%) are novel. The second aspect of our strategy was to complement this subtracted library with genes known to be involved in myeloid cell differentiation and function. The resulting cDNAs were arrayed on polylysine-coated glass slides. The microarrays were used to analyze gene expression in primary and cultured murine bone marrow-derived progenitors. We found expression of various types of genes, including regulatory cytokines and their receptors, signal transduction genes, and transcription factors. To assess gene expression during myeloid differentiation, we examined patterns of change during induced differentiation of EML cells. Several hundred of the genes underwent fluctuations in expression level during myeloid cell differentiation. The complete database, accessible on the World Wide Web at http://yale130132115135.med.yale.edu/, allows for retrieval of information regarding these genes. Our microarray allows for genomewide expression analysis of myeloid stem cells, which will help in defining the regulatory mechanisms of stem cell differentiation.