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The World Health Organization verified that Singapore had eliminated endemic transmission of measles in October 2018. This report summarizes the evidence presented to the Regional Verification Commission for Measles and Rubella Elimination, comprising information about immunization schedules; laboratory testing protocols and the surveillance system; and data on immunization coverage and the epidemiology of cases. Between 2015 and 2017, a total of 246 laboratory confirmed cases of measles were reported. The source or country of infection was unknown for most cases (195; 79.3%). There were 22 clusters, ranging from two to five cases. The most common genotypes detected were D8 and D9. Transmission of B3 was interrupted in 2017, and H1 cases were sporadic and imported. Phylogenetic analyses of the D8 isolates showed the existence of 13 lineages or clusters. Although a few lineages were circulating concurrently, no lineage propagated continuously for a prolonged period, and transmission of each lineage eventually stopped. Although cases and clusters were reported yearly, molecular data showed that none of the lineages resulted in prolonged transmission. There were fewer measles cases in 2017 compared with 2016. The higher number of clusters was likely due to the overall increase in cases because cluster sizes remained small. The occurrence of small clusters is not unexpected since measles is highly infectious. The majority of imported cases did not result in secondary transmission. With the global increase in the number of measles cases, Singapore needs to stay vigilant and continue to promptly test suspected cases; vaccination is the key to preventing infection.

We conducted a prospective environmental surveillance study to investigate the air, surface, dust and water contamination of a room occupied by a patient infected with Monkeypox virus (MPXV) at various stages of his illness. The patient tested positive for MPXV from a throat swab and skin lesions. Environmental sampling was conducted in a negative pressure room with 12 unidirectional HEPA air changes per hour and daily cleaning of the surfaces. A total of 179 environmental samples were collected on days 7, 8, 13, and 21 of his illness. Air, surface, and dust contamination was highest during the first eight days of the illness, with a gradual decline to the lowest contamination level by day 21. Viable MPXV was isolated from surfaces and dust samples and no viable virus was isolated from the air and water samples.SynopsisInadequate research prevail on the mode of transmission for monkeypox virus. This study reports the findings of viable monkeypox virus from the patient environment, highlighting its implications for human health and impact on infection and prevention control measures.

Social media is becoming a viable channel to seek health information. However, the effects of social media on health knowledge have been inconsistent in the existing literature. Drawn upon the cognitive mediation model, this study examined the motivations influencing social media use for human papillomavirus (HPV) information and explored the underlying pathways linking social media use to HPV knowledge. With two-wave online surveys conducted in China, we found that three motivations of social media use, namely surveillance, anticipated interaction, and guidance, were positively associated with information discussion on social media, which increased perceived information overload that was negatively related to knowledge. In addition, patient empowerment positively moderated the effects of motivations on information discussion.

In the wake of the US 2016 Presidential Election, concerns about misinformation traversing on social media have heightened. Since then, much of the public discourse has been on developing effective strategies to combat the spread of misinformation online. While several studies have focused on the effects of a mixed/hybrid regime of information channels on political participation and campaigns, we know little about how the existence of a hybrid media system exposes people to misinformation during an election cycle. Using a nationally representative survey administered during the 2019 Indonesian election ( N = 1,820), we find evidence for the prominence of traditional media as well as face-to-face discussions: political use of traditional media such as newspapers and TV as well as sharing of political information through face-to-face discussions are found to be positively associated with at least one measure of misinformation exposure. As for the social media communicative pathways, only political use of WhatsApp and Instagram are found to be positively associated with misinformation exposure; that no similar effects are observed for Facebook and Twitter attests, to some extent, to the efficacy of strategies aimed at combating misinformation implemented on such platforms. By considering social media, traditional media, and face-to-face communication in a context of a less digitalized hybrid media environment, this article provides a more comprehensive framework and novel empirical data to study misinformation exposure beyond the context of Western democracies.

Supplemental material, sj-docx-1-sms-10.1177_20563051221122792 for Who Gets Exposed to Political Misinformation in a Hybrid Media Environment? The Case of the 2019 Indonesian Election by Taberez Ahmed Neyazi, Aaron Yi Kai Ng, Ozan Kuru and Burhanuddin Muhtadi in Social Media + Society

The COVID-19 pandemic unleashed a torrent of conspiracy theories across different social media platforms. Parallel to this conspiracy wave was a heightened sense of nationalism, which manifested through both in-group solidarity and perceived out-group threats. In this study, we examine how individuals’ use of government social media to gather political information correlated with nation-related conspiracy beliefs during the pandemic. Data were collected from 745 subjects in China and analyzed through path analyses, which allowed us to examine the direct association with political information consumption from government social media and the indirect association with nationalism on conspiracy beliefs. The results indicated that the use of government social media to gather political information was associated with greater beliefs in nation-variant COVID-19 conspiracies, both directly and through different mediations of nationalism. Our findings highlight the importance of examining government social media use and how nationalism can have differentiated mediation effects on beliefs in conspiracy theories.

A measles outbreak involving 19 adults in a home for the intellectually disabled occurred in Singapore in 2019. Further investigation, including a serological survey, was conducted. Mass vaccination and infection control measures were implemented, terminating further secondary transmission. Seropositivity among residents aged 40 to 49 years (90.7%; 95% confidence interval = 78.4%, 96.3%) was lower than among the Singapore adult population (P

Background The largest West African monkeypox outbreak began September 2017, in Nigeria. Four individuals traveling from Nigeria to the United Kingdom (n = 2), Israel (n = 1), and Singapore (n = 1) became the first human monkeypox cases exported from Africa, and a related nosocomial transmission event in the United Kingdom became the first confirmed human-to-human monkeypox transmission event outside of Africa. Methods Epidemiological and molecular data for exported and Nigerian cases were analyzed jointly to better understand the exportations in the temporal and geographic context of the outbreak. Results Isolates from all travelers and a Bayelsa case shared a most recent common ancestor and traveled to Bayelsa, Delta, or Rivers states. Genetic variation for this cluster was lower than would be expected from a random sampling of genomes from this outbreak, but data did not support direct links between travelers. Conclusions Monophyly of exportation cases and the Bayelsa sample, along with the intermediate levels of genetic variation, suggest a small pool of related isolates is the likely source for the exported infections. This may be the result of the level of genetic variation present in monkeypox isolates circulating within the contiguous region of Bayelsa, Delta, and Rivers states, or another more restricted, yet unidentified source pool.

Microalgae are a potential source of valuable products including drugs, chemicals, food supplements, biofuels, animal feed and fertilizers. In outdoor culture, biomass productivity is dependent on ...

In May 2019, we investigated monkeypox in a traveler from Nigeria to Singapore. The public health response included rapid identification of contacts, use of quarantine, and postexposure smallpox vaccination. No secondary cases were identified. Countries should develop surveillance systems to detect emerging infectious diseases globally. Published version

Background: Two measles outbreaks occurred in migrant worker dormitories in Singapore in 2019. We report the outbreak investigation and use of ring vaccination to contain transmission. Methods: We collected clinical and epidemiological data from laboratory-confirmed measles cases and conducted field investigations to examine the interactions between dormitory residents. Two measles seroprevalence studies were performed using 1136 residual sera obtained from Bangladeshi, Chinese and Indian workers previously enrolled in 2016-19 for a study on latent tuberculosis and 101 samples prospectively collected from healthy workers residing on the same level as the index cases. We administered measles, mumps and rubella vaccine to close contacts and dormitory residents residing on the same level as a case (ring vaccination). The effectiveness of ring vaccination in a dormitory of varying contact patterns and population immunity was also evaluated using simulation models. Findings: From Jun 14 to Jul 29, 2019, there were 12 laboratory-confirmed cases of measles from two distinct dormitory outbreaks and 214 close contacts along with 1532 dormitory residents were vaccinated. Measles Immunoglobulin G was detected in 99.5% (95% CI 98.9 – 99.8) of the residual sera and in all blood samples. Outbreaks simulated in a dormitory of 24 194 people, with 90% immunity and an average of 25 contacts per person, revealed a significant reduction in the final outbreak size from 2026 (IQR 1986–2058) cases to 8 (IQR 3– 26) cases when ring vaccination was implemented. In addition, vaccinating each person would avert two new cases. At higher population immunity of 93% and an average of 15 contacts per person, the maximum outbreak size was reduced by 50% with ring vaccination. Interpretation: Measles outbreaks can occur in densely populated areas with high contact rates despite high population immunity. Ring vaccination may be a strategy to protect susceptible contacts to minimise the risk of large outbreaks. Funding Statement: The authors stated: "None." Declaration of Interests: The authors declare no competing interest. Ethics Approval Statement: All epidemiological investigations and outbreak containment measures were implemented under the Infectious Diseases Act, which provides for the use of outbreak investigation data for analysis and evaluation.

Bifidobacteria are anaerobes and are difficult to culture in conventional fermentation system. It was observed that Bacillus subtilis natto enhanced growth of Bifidobacterium animalis subsp. lactis v9 by about 3-fold in a whole soybean solid-state co-fermentation, in a non-anaerobic condition. For the purpose of understanding the metabolic interactions between Bif. animalis subsp. lactis v9 and Ba. subtilis natto, the transcriptome of Bif. animalis subsp. lactis v9 and Ba. subtilis natto was analyzed in single and mixed cultures using RNA-Seq. Compared with the single culture, 459 genes of Bif. animalis subsp. lactis v9 were up regulated and 21 were down regulated in the mixed culture with Ba. subtilis natto, with more than 2-fold difference. Predictive metagenomic analyses suggested that Ba. subtilis natto up regulated transport functions, complex carbohydrates and amino acid metabolism, DNA repair, oxydative stress-related functions, and cell growth of Bif. animalis subsp. lactis v9. In the mixed culture with Bif. animalis subsp. lactis v9, only 3 transcripts of Ba. subtilis natto were over-expressed and 3115 were under-expressed with more than 2-fold difference. The highest down-regulated genes were those involved in carbohydrate and amino acid metabolism. The data presented here demonstrated a parasitic-like interaction regulated at the transcription level, between Ba. subtilis natto and Bif. animalis subsp. lactis in the mixed culture. The over-expression of genes involved in substrate uptake and metabolism in Bif. animalis subsp. lactis in the mixed culture nevertheless, led to its higher cell concentration in the nutrient rich whole soybean medium.

Zika virus (ZIKV) is an ongoing global public health emergency with 70 countries and territories reporting evidence of ZIKV transmission since 2015. On 27 August 2016, Singapore reported its first case of local ZIKV transmission and identified an ongoing cluster. Here, we report the genome sequences of ZIKV strains from two cases and find through phylogenetic analysis that these strains form an earlier branch distinct from the recent large outbreak in the Americas.

The developmental cycle of the obligate marine antibiotic producer actinobacterium Salinispora arenicola isolated from a Great Barrier Reef marine sponge was investigated in relation to mycelium and spore ultrastructure, synthesis of rifamycin antibiotic compounds, and expression of genes correlated with spore formation and with rifamycin precursor synthesis. The developmental cycle of S. arenicola M413 on solid agar medium was characterized by substrate mycelium growth, change of colony color, and spore formation; spore formation occurred quite early in colony growth but development of black colonies occurred only at late stages, correlated with a change in spore maturity in relation to cell wall layers. Rifamycins were detected throughout the growth cycle, but changed in relative quantity at particular phases in the cycle, with a marked increase after 32 days. Expression of the spore division gene ssgA and the rifK gene for 3-amino-5-hydroxybenzoate synthase responsible for rifamycin precursor synthesis was seen even at early stages of the growth cycle. ssgA expression significantly increased between days 26 and 31, but rifK expression effectively remained constant throughout the growth cycle, consistent with the early synthesis of rifamycin. Factors other than precursor synthesis may be responsible for an observed late increase in rifamycin production. A useful approach for measuring and exploring the regulation of antibiotic synthesis and gene expression in the marine natural product producer S. arenicola has been established.

Eleven isolates of Mycobacterium species as well as an antimycobacterial Salinispora arenicola strain were cultured from the sponge Amphimedon queenslandica. The 16S rRNA, rpoB, and hsp65 genes from these Mycobacterium isolates were sequenced, and phylogenetic analysis of a concatenated alignment showed the formation of a large clade with Mycobacterium poriferae isolated previously from another sponge species. The separation of these Mycobacterium isolates into three species-level groups was evident from sequence similarity and phylogenetic analyses. In addition, an isolate that is phylogenetically related to Mycobacterium tuberculosis was recovered from the sponge Fascaplysinopsis sp. Several different mycobacteria thus appear to co-occur in the same sponge. An actinobacterium closely related to S. arenicola, a known producer of the antimycobacterial rifamycins, was coisolated from the same A. queenslandica specimen from which mycobacteria had been isolated. This Salinispora isolate was confirmed to synthesize rifamycin and displayed inhibitory effects against representatives from two of three Mycobacterium phylotype groups. Evidence for antagonism of sponge-derived Salinispora against sponge-derived Mycobacterium strains from the same sponge specimen and the production of antimycobacterial antibiotics by this Salinispora strain suggest that the synthesis of such antibiotics may have functions in competition between sponge microbial community members.

The upstream regulatory sequence (URS), NF1 region, enhancer, promoter, 1st exon, and intron A of human cytomegalovirus major immediate early gene (hCMV MIE) are evaluated for enhancing transient and stable gene expression levels in two industrial cell lines, CHO K1 and HEK293 using firefly luciferase (Fluc) and erythropoietin (EPO). As compared to the control vector which only contains the enhancer and promoter (EP), vectors containing the 1st exon (EPE) and intron A (EPEI) enhance transient expression levels of the two proteins by approximately 2.5- to 4.3-fold in the two cell lines. Addition of NF1 and URS to EP (NEP and UNEP) or EPEI (NEPEI and UNEPEI) results in a lesser effect on the expression. In stable transfections, UNEPEI provides the highest expression level in CHO K1 cells, yielding approximately 4.0-fold increase in Fluc expression and 2.5-fold increase in EPO expression. In HEK293 cells, EPE is the best and enhances Fluc and EPO expression by more than 2.0-fold. Such information is valuable for the development of optimal vectors to enhance transient and stable production of recombinant proteins in CHO K1 and HEK293 cells.

Microalgae are a diverse group of photosynthetic microorganisms that produce several useful products including biodiesel feedstock, bioactive molecules, human food, and animal feed. They can also be used in biological carbon dioxide sequestration. Photosynthetic microalgal cultures are prone to several biological limitations, such as photoinhibition and slow response to varying light irradiance, which result in low product yield. These limitations can be overcome by methods such as selection and genetic engineering of microalgal strains. In particular, lipid productivity and fatty acid compositions of microalgal cultures can be enhanced through metabolic engineering. Microalgae can also be genetically modified to secrete fatty acids into the culture medium to facilitate harvesting of fatty acids. Culture systems and photobioreactors can also be designed to maximize productivity of large-scale microalgal cultures.

Aims: To investigate the effects of growth conditions related to marine habitat on antibiotic production in sponge-derived Salinispora actinobacteria. Methods and Results: Media with varying salt concentration were used to investigate the effects of salinity in relation to Salinispora growth and rifamycin production. The chemotypic profiles of the model strain Salinispora arenicola M413 was then assessed using metabolomic fingerprints from high-pressure liquid chromatography with diode array detection (HPLC-DAD) and multivariate data analysis, before extending this approach to two other strains of S. arenicola. Fingerprint data were generated from extracts of S. arenicola broth cultures grown in media of varying salt (NaCl) concentrations. These fingerprints were then compared using multivariate analysis methods such as principal components analysis (PCA) and orthogonal projection to latent structures discriminant analysis (OPLS-DA). From the analysis, a low-sodium growth condition (1% NaCl) was found to delay the onset of growth of the model S. arenicola M413 strain when compared to growth in media with either 3% artificial sea salt or 3% NaCl. However, low-sodium growth conditions also increased cell mass yield and contributed to at least a significant twofold increase in rifamycin yield when compared to growth in 3% artificial sea salt and 3% NaCl. Conclusions: The integration of HPLC-DAD and multivariate analysis proved to be an effective method of assessing chemotypic variations in Salinispora grown in different salt conditions, with clear differences between strain-related chemotypes apparent due to varying salt concentrations. Significance and Impact of the Study: The observed variation in S. arenicola chemotypic profiles further suggests diversity in secondary metabolites in this actinomycete in response to changes in the salinity of its environment.

Eleven isolates of Mycobacterium species as well as an antimycobacterial Salinispora arenicola strain were cultured from the sponge Amphimedon queenslandica. The 16S rRNA, rpoB, and hsp65 genes from these Mycobacterium isolates were sequenced, and phylogenetic analysis of a concatenated alignment showed the formation of a large clade with Mycobacterium poriferae isolated previously from another sponge species. The separation of these Mycobacterium isolates into three species-level groups was evident from sequence similarity and phylogenetic analyses. In addition, an isolate that is phylogenetically related to Mycobacterium tuberculosis was recovered from the sponge Fascaplysinopsis sp. Several different mycobacteria thus appear to co-occur in the same sponge. An actinobacterium closely related to S. arenicola, a known producer of the antimycobacterial rifamycins, was coisolated from the same A. queenslandica specimen from which mycobacteria had been isolated. This Salinispora isolate was confirmed to synthesize rifamycin and displayed inhibitory effects against representatives from two of three Mycobacterium phylotype groups. Evidence for antagonism of sponge-derived Salinispora against sponge-derived Mycobacterium strains from the same sponge specimen and the production of antimycobacterial antibiotics by this Salinispora strain suggest that the synthesis of such antibiotics may have functions in competition between sponge microbial community members.

Staurosporine has been shown to possess an array of important biological properties such as anti-fungal, anti-bacterial, antihypertensive and anti-cancer. Methods available to screen any plant or bacterial extract for this compound are lengthy and laborious. We present here a simple HPLC-MS-MS method for the highly selective identification of Staurosporine in various strains of the marine sponge-derived bacterium Salinispora. Gradient elution using acetonitrile/water/ammonium acetate was used to separate Staurosporine from the matrix and positive ion electrospray mass spectrometry was used for detection and confirmation. Presence of Staurosporine in bacterial extracts was confirmed by matching retention times and parent-daughter ion mass spectra (using Multiple Reaction Monitoring, MRM mode) of the standard Staurosporine with those of the bacterial extracts. Detection of Staurosporine was achieved down to 11 ng/mL bacterial extract. This method can be easily adapted to screen any plant extract for Staurosporine. The simplicity and the speed of this method make it possible for the analyst to screen a large number of extracts before embarking on lengthy and costly isolation and purification of Staurosporine in a selected few.

Background For many years, increasing demands for fossil fuels have met with limited supply. As a potential substitute and renewable source of biofuel feedstock, microalgae have received significant attention. However, few of the current algal species produce high lipid yields to be commercially viable. To discover more high yielding strains, next-generation sequencing technology is used to elucidate lipid synthetic pathways and energy metabolism involved in lipid yield. When subjected to manipulation by genetic and metabolic engineering, enhancement of such pathways may further enhance lipid yield. Results In this study, transcriptome profiling of a random insertional mutant with enhanced lipid production generated from a non-model marine microalga Dunaliella tertiolecta is presented. D9 mutant has a lipid yield that is 2- to 4-fold higher than that of wild type. Using novel Bag2D-workflow scripts developed and reported here, the non-redundant transcripts from de novo assembly were annotated based on the best hits in five model microalgae, namely Chlamydomonas reinhardtii, Coccomyxa subellipsoidea C-169, Ostreococcus lucimarinus, Volvox carteri, Chlorella variabilis NC64A and a high plant species Arabidopsis thaliana. The assembled contigs (~181 Mb) includes 481,381 contigs, covering 10,185 genes. Pathway analysis showed that a pathway from inositol phosphate metabolism to fatty acid biosynthesis is the most significantly correlated with higher lipid yield in this mutant. Conclusions Herein, we described a pipeline to analyze RNA-Seq data without pre-existing transcriptomic information. The draft transcriptome of D. tertiolecta was constructed and annotated, which offered useful information for characterizing high lipid-producing mutants. D. tertiolecta mutant was generated with an enhanced photosynthetic efficiency and lipid production. RNA-Seq data of the mutant and wild type were compared, providing biological insights into the expression patterns of contigs associated with energy metabolism and carbon flow pathways. Comparison of D. tertiolecta genes with homologs of five other green algae and a model high plant species can facilitate the annotation of D. tertiolecta and lead to a more complete annotation of its sequence database, thus laying the groundwork for optimization of lipid production pathways based on genetic manipulation. Electronic supplementary material The online version of this article (doi:10.1186/s13068-015-0382-0) contains supplementary material, which is available to authorized users.