This presentation provides an introduction to diarrheal diseases caused by bacteria, viruses, parasites and other disease causing agents or pathogens. Furthermore, we’ll look at the range of syndromes associated with diarrhea and uncover two significant pathogens: rotavirus and vibrio cholera. Finally, we’ll delve into methods for managing diarrheal diseases and the significance of sanitation in preventing diarrheal diseases.

In this activity on page 1 of the PDF, learners compare the relative sizes of biological objects (like DNA and bacteria) that can't be seen by the naked eye. Learners will be surprised to discover the range of sizes in the microscopic world. This activity can be followed up with a second activity, "What's in a microbe?", located on page 3 in the same resource.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"Sometimes viruses release RNA into the host’s cytosol, and detecting that RNA is a critical part of the host’s antiviral immune response. But cells need to have a set of brakes to regulate these responses, otherwise they can trigger harmful overproduction of type I interferon proteins. The kinase MST4 is one part of this ‘braking’ system. Previous work found that MST4 limits damaging inflammatory responses by adding a phosphate group to the adaptor protein TRAF6. But researchers wanted to know how MST4 might regulate type I interferon production. So, in a recent study, they determined that MST4 also competes with another TRAF protein, TRAF3, to bind MAVS. MAVS is a key antiviral signaling protein, and when MST4 binds it instead of TRAF3, type I interferon production is slowed. They also found that MST4 facilitated interactions between MAVS and the ubiquitin ligase Smurf1, which encouraged degradation of MAVS..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"The laboratory and computational tools available to microbiome researchers have greatly improved in recent years, especially in assembling genomes from complex communities. Most of the research to date has focused on macrodiversity, which is classical ecology metrics like population abundance, α-diversity, and β-diversity. But microdiversity — population genetics metrics like single nucleotide polymorphisms (SNPs) and selective pressures — is important to consider. There are several technical and accessibility issues that hinder widespread analysis of microdiversity in metagenomic datasets, but the recently developed open-access software tool MetaPop is designed to close this gap. MetaPop provides a user-friendly interface to analyze both the macro- and microdiversity of microbial and viral community metagenomes. For small datasets, MetaPop can be run on a laptop, making it a practical choice for non-bioinformaticians or labs without access to high-powered computing..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.

This course focuses on the fundamentals of tissue and organ response to injury from a molecular and cellular perspective. There is a special emphasis on disease states that bridge infection, inflammation, immunity, and cancer. The systems approach to pathophysiology includes lectures, critical evaluation of recent scientific papers, and student projects and presentations.
This term, we focus on hepatocellular carcinoma (HCC), chronic-active hepatitis, and hepatitis virus infections. In addition to lectures, students work in teams to critically evaluate and present primary scientific papers.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"Phospholipid scramblase 1 (PLSCR1) is the most studied member of its protein family and has a complex array of suggested functions. While PLSCR1 was first described as a plasma membrane protein, it has subsequently been found in other cellular compartments and implicated in numerous cellular pathways including apoptosis, intracellular trafficking of membrane proteins, and pro-inflammatory events. PLSCR1 interacts with various effectors, mediators, and regulators that then contribute to distinct cellular processes. While most PLSCR1 interactors are thought to be cell-type specific, the mechanisms of PLSCR1's regulatory functions are often shared. But not all PLSCR1 interactors are endogenous in origin; PLSCR1 also interacts with exogenous viral proteins. These interactions regulate viral uptake and spread in both pro- and anti-viral ways..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"Microbes are widely known to spread disease, but could they also help prevent it? A look inside in the mosquito gut reveals a community of microbes fit for the job. Mosquitoes are well-known vectors of disease, transmitting West Nile and Zika virus and the pathogens that cause malaria and dengue fever. Unfortunately, traditional control methods have led to insecticide resistance and negative impacts on other organisms, but mosquitoes, like other animals, also host non-disease-causing microbes in their gut. These benign microorganisms can directly interact with the deadly pathogens harbored by these insects. They can also affect mosquito traits influencing pathogen transmission, such as their population density, development, biting rate, and survival. For example, certain bacterial strains can reduce female fertility and the egg-hatching rate, while others can protect mosquitoes from environmental stress..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"With the global health crisis of COVID-19 having widespread effects on economies and communities, understanding environmental factors that affect the transmissibility of SARS-CoV-2 is critical. Following up on a previous study demonstrating that removing shoes indoors may lower the COVID-19 mortality rate, researchers in Japan evaluated the correlation of a unique metric with COVID-19 morbidity and mortality. Tatami is a type of straw mat used for flooring in traditional Japanese-style rooms. Because people customarily remove their shoes before entering tatami rooms researchers used the density of tatami stores in a locale as a proxy for the cultural practice of shoe removal. They found that while COVID-19 morbidity and mortality increased with population density there was a negative correlation between the number of tatami stores per 100,000 people – and therefore the likelihood of shoe removal – and the number of COVID-19 cases ..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.

Student teams practice water quality analysis through turbidity measurement and coliform bacteria counts. They use information about water treatment processes to design prototype small-scale water treatment systems and test the influent (incoming) and effluent (outgoing) water to assess how well their prototypes produce safe water to prevent water-borne illnesses.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"Tiny but tenacious, the tick is one of the most dangerous creatures on earth—and perhaps one of the most misunderstood. Because while typically associated with Lyme disease, ticks can actually harbor more than 120 different species of bacteria, each a unique source of infection. Unfortunately, the one-microbe, one-disease myth surrounding the tick extends well beyond the court of public opinion. The lack of broad-spectrum diagnostics in the clinic means that a single sufferer of tick-borne disease may spend up to $60,000, or 54,000 €, on more than 11 visits, doctors, and tests just to get a proper diagnosis. A 2018 blood analysis of 432 individuals showing symptoms of Lyme disease puts the problem in perspective—and calls for revamped screening procedures that decrease the probability of missed or misdiagnosis..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.

Students simulate the spread of a virus such as HIV through a population by "sharing" (but not drinking) the water in a plastic cup with several classmates. Although invisible, the water in a few of the cups has already be tainted with the "virus" (sodium carbonate). After all the students have shared their liquids, the contents of the cups are tested for the virus with phenolphthalein, a chemical that causes a striking color change in the presence of sodium carbonate. Students then set about trying to determine which of their classmates were the ones originally infected with the virus.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"The interactions between viruses and prokaryotes play a key role in shaping microbiomes. However, little is known about the factors influencing host-virus interaction networks, especially when it comes to host factors. To close this gap, researchers constructed a host-provirus network out of over 7,000 species-level prokaryote genomes from many environments. Proviruses are virus genomes that have been integrated into the host genome, allowing researchers to detect them from available genomic datasets. Using this host-provirus network, the researchers then calculated the host interaction specialization, which quantifies how specialized a given host is in relation to the available interacting virus partners. Broadly, fast growing prokaryotes showed less virus specificity than slow growers. This negative growth rate-specialization relationship was widespread across the Earth’s microbiomes..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"Mitochondrial stress is a key trigger of innate immune responses. Sources of stress include environmental changes, genetic mutations, and pathogenic infection. Mitochondria respond by releasing mitochondrial DAMPs and cytochrome c into the cytosol that induce inflammation and apoptosis through activating inflammasomes, cGAS and apoptotic caspases. One way cells manage mitochondrial stress is by eliminating dysfunctional mitochondria, a process known as “mitophagy.” Mitophagy regulatory pathways are classified as ubiquitin (Ub)-dependent or Ub-independent (receptor-dependent). Growing evidence shows that mitophagy can be induced by certain bacteria and viruses. Co-opting the mitophagy process enables these pathogens to evade hosts’ immune defense. Much remains to be learned about the mechanisms that pathogens employ to hijack host mitophagy. Understanding these mechanisms could point to new therapeutic strategies for fighting infection and related diseases..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"Primary viral infections and reactivations are common complications after allogeneic hematopoietic stem cell transplantation (allo-HSCT). Some allo-HSCT recipients develop graft-versus-host disease (GvHD) and must be highly immunosuppressed, making them more vulnerable to infection. In particular, weakly pathogenic or commensal viruses may cause illnesses in these patients yet remain undetected in the clinic. A new study sought to identify the viruses acquired by patients following allo-HSCT. Using metagenomics next-generation sequencing, they evaluated 25 adult allo-HSCT recipients from 2016 to 2019 with acute or chronic GvHD. During a period of immunosuppression with a median duration of 5.1 months, the GvHD mortality rate for these patients was 36%. Sequence analysis detected viral nucleotide sequences in 24 out of 25 patients, with ≥3 distinct viruses detected in 16 patients..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"Viruses that infect bacteria and archaea are abundant in human and environmental microbiomes. Their roles in manipulating, killing, and recycling microbes makes them key players in environmental processes and human health and disease, including inflammatory bowel diseases. In spite of their importance, the tools available for analyzing viral genomes are limited. Now, a new tool allows researchers to identify viruses and predict their functions using genomic data. VIBRANT (Virus Identification By iteRative ANnoTation), is the first software to use a hybrid machine learning and protein similarity approach. going beyond traditional limitations to maximize the identification of highly diverse viruses. In validation experiments with reference datasets, VIBRANT recovered higher-quality virus sequences and reduced false identification of non-viral genome fragments compared to other identification programs..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"Viruses are a critical component of biosphere and human ecosystems, directly influencing human health and disease and controlling the output of engineered ecosystems. Unfortunately for scientists studying them, most viral signals remain hidden in sequence datasets due to a lack of optimal identification tools. A new tool aims to make virus identification easier. VirSorter2 is a DNA and RNA virus identification tool that leverages genome-informed database advances to improve the accuracy and range of virus sequence detection. Compared with other tools, VirSorter2 performs more consistently with high accuracy across diverse viruses and minimized errors associated with atypical cellular sequences, including eukaryotic genomes and plasmids. VirSorter2 is also modular, allowing it to expand to newly discovered viruses through the design of new viral classifiers..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.

Students learn how viruses invade host cells and hijack the hosts' cell-reproduction mechanisms in order to make new viruses, which can in turn attack additional host cells. Students also learn how the immune system responds to a viral invasion, eventually defeating the viruses -- if all goes well. Finally, they consider the special case of HIV, in which the virus' host cell is a key component of the immune system itself, severely crippling it and ultimately leading to AIDS. The associated activity, Tracking a Virus, sets the stage for this lesson with a dramatic simulation that allows students to see for themselves how quickly a virus can spread through a population, and then challenges students to determine who the initial bearers of the virus were.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"Marine sponges are an ecologically important component of the sea floor. In addition to providing a habitat for a diverse array of marine species, they also mediate biogeochemical fluxes by filtering organic matter, facilitating nutrient consumption and release. But while their interaction with picoplankton, bacteria, and archaea has been extensively studied, the interaction of sponges with viral-like particles is poorly understood. A recent study examined this ‘dark matter’ in this ecologically important symbiosis. Researchers assessed nine sponge species from the Great Barrier Reef and seven species from the Red Sea. Viromic sequencing revealed host-specific and site-specific patterns in viral communities. All sponge species were dominated by the bacteriophage order Caudovirales, but large DNA virus families were also represented. While core viral functions were consistent across viromes, putative auxiliary metabolic genes (AMGs) were differentially represented..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.

Zika is an arbovirus infection transmitted by several different species of Aedes mosquitoes, including Aedes aegypti in the New World. Towards the end of 2015, the Pan American Health Organization announced a possible link between zika and congenital birth defects, in particularly a neurodevastating birth defect known as microcephaly. The causal link between zika and microcephaly has still not been confirmed, but preliminary evidence for an association has been found. The impact of zika virus should be treated with the utmost seriousness as the effects could be devastating. In response a call for research on the outbreak and a new PLOS Collection, which will collate research and other resources related to the outbreak, have been launched.

This resource is a video abstract of a research paper created by Research Square on behalf of its authors. It provides a synopsis that's easy to understand, and can be used to introduce the topics it covers to students, researchers, and the general public. The video's transcript is also provided in full, with a portion provided below for preview:

"Bacteriophages are viruses that infect and kill bacteria as a way to control their host populations. Complex soil microbial communities can be better understood by studying interactions between phages and bacteria. In a new paper, researchers quantified the extent to which phages drive the assembly and functioning of soil bacterial communities. They tested natural and sterilized soil incubated with pairs of soil communities, applying various native and non-native phage suspensions. Key differences in microbiota were dependent on the community assembly scenarios, suggesting that host community diversity and composition are important factors in phage behavior, while phage pressure may impact soil microbial functions. The results highlight the importance of phage interactions with soil bacterial communities in understanding the dynamics and functioning of terrestrial ecosystems..."

The rest of the transcript, along with a link to the research itself, is available on the resource itself.