Week 1. Intro and Review to Med Micro PDF

UNIVERSITY OF THE PHILIPPINES BAGUIO COLLEGE OF SCIENCE DEPARTMENT OF BIOLOGY OUTLINE I. Objectives II. Introduction III. Application of Microbiology IV. Latest news in Microbiology V. Branches of study within Microbiology VI. History a. Spontaneous Generation c. Germ Theory Disease b. Emerging and...

UNIVERSITY OF THE PHILIPPINES BAGUIO COLLEGE OF SCIENCE DEPARTMENT OF BIOLOGY OUTLINE I. Objectives II. Introduction III. Application of Microbiology IV. Latest news in Microbiology V. Branches of study within Microbiology VI. History a. Spontaneous Generation c. Germ Theory Disease b. Emerging and re-emerging diseases VII. Characteristics of microbes a. Naming microorganisms b. Major groups of Medically Important Microorganisms c. Epidemiology of Infectious Diseases d. Infectious Disease Process VIII. Types of Hosts IX. The Infectious Agents X. Host-Parasite Relationship XI. Transmission a. Portal of Entry b. Portal of Exit c. Gradient of Infection d. Patterns of Infection e. Acquisition of Disease XII. Sample Case I. OBJECTIVES • Review of Microbiology Concepts & Introduction of Medical Microbiology • Discuss history of Microbiology • Differentiate the major groups of medically important microorganisms • Discuss the Natural Process of Infectious Disease • Discuss the updates and importance of Human Microbiome • Discuss Host-Parasite Relationship II. INTRODUCTION MICROBIOLOGY - The study of organisms too small to be seen without magnification o Bacteria 38-41% o Viruses 14-15% o Fungi 22-23% o Protozoa 4-5% o Helminths (worms) 20% o Algae – 🕮 Microbiology is the study of microorganisms, a large and diverse group of microscopic organisms that exist as single cells or cell clusters; it also includes viruses, which are microscopic but not cellular. Why do we need to study microbiology? Prevent panic within the community, prevent infection post-op, identify emerging and reemerging diseases, prevent outbreaks (Ex. Coronavirus causing SARS). Drug development, laboratory tests, industrial microbiology III. APPLICATIONS OF MICROBIOLOGY • Food industry - Food technology utilizes the principles of microbiology for the dev’t of alcoholic beverages like beer, breads • Garbage degradation/decomposition • Biotechnology (i.e. antibiotics development, prebiotics, probiotics) • Genetic engineering - Genomes are manipulated to develop stronger agents or enzymes to cure infections • Topics in movies about outbreak and epidemics (i.e. Contagion, Outbreak) • Food substitute (i.e. Quorn Chik ‘n Nuggets: a meat substitute from the fungi Fusarium venenatum. It is made up of fungi combined with minerals, nitrogen and oxygen plus albumin) IV. LATEST NEWS IN MICROBIOLOGY • E. coli capsule to be used as vehicle to deliver vaccine 🕮Seen in stool and large intestine • Alcanivorax: Hydrocarbon-degrading bacteria 🕮 Oil-degrading marine bacterium; Becomes the predominant microbe in oil-contaminated open oceans and coastal waters when nitrogen and phosphorus are not limiting • CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats): used to cut defective genetic materials that cause disease in humans; initially identified through a bacterium protecting itself from a virus attack 🕮 Scientist notice that there were bacteria infected by virus that they can control side effects. When they investigate, they found out that the bacteria have enzymes that can cut pathologic proteins that are infected by the virus. Bio 125 – INTRODUCTION OF MEDICAL MICROBIOLOGY Page 1 of 10 UNIVERSITY OF THE PHILIPPINES BAGUIO COLLEGE OF SCIENCE DEPARTMENT OF BIOLOGY Instead of worsening condition, they survived the infection. 🕮 Applications of CRISPR in research, medicine, and biotechnology includes rapid generation of cellular and animal models, functional genomic screens, transcriptional modulation and epigenetic control. • Human Microbiome 🕮 Normal flora are those microorganisms that are permanent residents of the body that everyone has. This normal flora helps in our metabolism. The microbiome is the clustered genome of all those microorganisms. 🕮 There is a human microbiome project to map out all the genetic materials of the microorganisms. Microorganisms not just help in digestion but also in the immune system and plays a role in obesity, diabetes 🕮 Altered microbiome after caesarean section impacts baby’s immune system 🕮 Gut microbiome differ between obese and lean people. 🕮 Microorganisms have a tremendous impact on all life and the physical and chemical makeup of our planet. They are also responsible for cycling the chemical elements essential for life, including carbon, nitrogen, sulfur, hydrogen, and oxygen. POOP IN A PILL: Fecal transplant. If you are a patient having diarrhea, you had some abnormalities with the normal flora (good bacteria died and pathogenic bacteria flourished). So they wanted to transfer the good bacteria from a normal person to the sick person. Inside the pill is the microbiome of the normal individual. Effect is similar to Erceflora (drug for diarrhea 🔍 search for this and investigate its mechanism of action). VI. HISTORY A. SPONTANEOUS GENERATION Early belief that some forms of life could arise from vital forces present in nonliving or decomposing matter 🕮 Antoine van Leeuwenhoek - Father of Microbiology; First to observe living microbes (1674); His single lens magnified up to 300X 🕮 Otto Muller - Organized bacteria into genera and species. 🕮 Louis Pasteur - Developed aseptic techniques; developed a rabies vaccine B. GERM THEORY Friedrich Henle - Microorganisms were responsible for causing diseases, Germ theory A. Joseph Lister - In 1860s used a chemical disinfectant to prevent surgical wound infections B. Robert Koch: 1876. Believed that Bacillus anthracis causes anthrax and provided the experimental steps C. Heinrich Hermann Robert Koch Koch's postulate; Developed pure culture methods; Identified cause of anthrax and TB. https://www.youtube.com/watch?v=agglGItTWtk Figure 1. Koch’s postulate. ★ _(Pls. study this 😊) V. BRANCHES OF STUDY WITHIN MICROBIOLOGY • Immunology • Public health microbiology and epidemiology • Food, dairy, and aquatic microbiology • Biotechnology • Genetic engineering and recombinant DNA technology (i.e. CRISPRs) 🕮 Biochemistry, molecular biology, and genetics provide the tools required for analysis of microorganisms. Bio 125 – INTRODUCTION OF MEDICAL MICROBIOLOGY Page 2 of 10 UNIVERSITY OF THE PHILIPPINES BAGUIO COLLEGE OF SCIENCE DEPARTMENT OF BIOLOGY VII. CHARACTERISTICS OF MICROBES Figure 2. History of Microbiology 🕮 1977 – DNA sequencing and PCR 🕮 By the time we reach 2006, we are already here in the molecular microbiology 🕮 Application of biochemistry and genetic engineering in the study of microbiology C. EMERGING AND RE-EMERGING DISEASES DECADE 1980-1989 1990-1999 2000-present ORGANISM HTLV-1, HTLV-2, HHV-6, HIV, Hepa C, helicobacter, toxin producing S. aureus HHV-8, Hepa E-G, Vibrio cholera 0139, Cryptosporidium SARS-corona, H5N1, H1N1, MERS-CoV, Meningococcemia, Leptospirosis, Ebola Figure 3. Cellular Morphology Among Different Microbes Table 2. Differences between eukaryotes and prokaryotes Characteristics Eukaryotes Prokaryotes Groups Algae, fungi, plants, protozoa, animals Bacteria Nucleus Classic membrane No nuclear membrane Mitochondria Present Absent Golgi bodies Present Absent ER Present Absent Ribosomes 80s 70s Cytoplasmic Membrane Contains sterols No sterols Reproduction Sexual and asexual Asexual (binary Fission Respiration Via mitochondria Via Cytoplasmic membrane Cell Wall Present for fungi Contains proteins, lipids and Peptidoglycan Size >5 micrometer 0.5-3.0 micrometer Chromosome DNA diploid genome Single circular DNA haploid 🕮 Another distinguishing characteristic of prokaryotes is their capacity to exchange small packets of genetic information. This information Bio 125 – INTRODUCTION OF MEDICAL MICROBIOLOGY Page 3 of 10 UNIVERSITY OF THE PHILIPPINES BAGUIO COLLEGE OF SCIENCE DEPARTMENT OF BIOLOGY may be carried on plasmids, small and specialized genetic elements that are capable of replication within at least one prokaryotic cell line. A. NAMING MICROORGANISMS • Binomial (scientific nomenclature)Gives each microbe 2 names • Genus: Always capitalized • Species (Not SPECIE pls. huhu): Lowercase • Both italicized or underline 🕮 Candida albicans is a normal flora but when our immune system weakens, this yeast will proliferate causing an infection (an example of opportunistic infection when the host has weakened immune system, an altered microbiota, or breached integumentary barriers). Ex ng madalas maapektuhan: yung mga nagchemotheraphy. B. EPIDEMIOLIGY OF INFECTIOUS DISEASES B. MAJOR GROUPS OF MEDICALLY IMPORTANT MICRORGANISMS • Bacteria: S. aureus, E. coli, V. cholera, S. pneumoniae Accdg. to shape: Coccus, Bacillus, Spirillum Accdg. to arrangement: Diplo, Staphylo, Strepto Accdg. to staining: Gram-positive, Gramnegative - Cause of the difference in staining: peptidoglycan layer • Fungi: Malassezia species, C. albicans • Virus: HIV, Hepatitis virus, Rotavirus, Human Papilloma Virus Accdg. to shape: Helical, Polyhedral/Icosahedral, Complex Accdg. to genetic material: RNA virus, DNA virus • Algae: Planktons, dinoflagellates • Protozoa • Virus Figure 5. Epidemiology of infectious diseases ★ Any imbalance in the interaction of an agent, host, and environment will result to a disease. Figure 6. Course of infectious agent Figure 4. Microorganism responsible for pathology of some diseases. a). Candida albicans, a yeast that can cause oral candidiasis aka oral thrush. This is caused by an overgrowth of fungal Candida b). Penicillium sp. causing nail infections 🕮 All of us can be a susceptible host and we can be reservoir as well. ★ An example of a disease that needs a portal of entry and exit is HIV. You cannot introduce an etiologic agent directly to the host if there’s no portal of entry/exit. You cannot get HIV thru aerosol or inhalation, mode of transmission is Bio 125 – INTRODUCTION OF MEDICAL MICROBIOLOGY Page 4 of 10 UNIVERSITY OF THE PHILIPPINES BAGUIO COLLEGE OF SCIENCE DEPARTMENT OF BIOLOGY direct contact. There should be portal of exit coming from the one with infection then there is a portal of entry to the host. ★ Another example is Dengue, it needs a reservoir. ★ Ex. A susceptible host living in a congested place acquired a pneumonia - Etiologic agent: Klebsiella or Pseudomonas pneumonia - Reservoir: human carriers (infected host) - Portal of exit: respiratory - Mode of transmission: droplets inhalation 🕮 If you are in the public health sector, with this process (Figure 5), which would be the cheapest mode to control an outbreak, what would you target? The cheapest and easiest would be the mode of transmission. VIII. TYPES OF HOSTS A. THE HUMAN HOST ★Come into the sterile world - Exposed areas acquire flora 🕮 Because of the microbiome project, scientist discovered that it is highly beneficial when the child is born through normal delivery because they get good bacteria - Closed areas remain sterile What are the parts that should remain sterile until we grow old? • CSF, meninges • Internal body sites (ex. Urinary bladder) • Pleural fluid (chest fluid, thoracentesis) • Peritoneal fluid (abdominal fluid, ascites) • Pericardial fluid • Bone • Joint fluid ★ Constant exposure ★ Normal Flora to microbes • Microbiome - Aggregate collection of microbial genomes in the microbiota (★genetic material of the microorganisms) • Core microbiome - Commonly shared microbial species among individuals at specific body sites; Although typically represented by a limited number of species, these comprise the largest proportion of the microbial population • Secondary Microbiome - Microbial species that contribute to the unique diversity of individuals at a specific body sites; Typically present in proportionately small numbers • Functional Redundancy - Required functions (e.g. Metabolism of nutrients, regulation of the immune response) that are provided by the diverse members of the microbiota • Taxonomic Diversity - The diverse number of species that comprise the microbiota • Prebiotic - Food ingredient that supports the growth of one or more members of the microbiota • Probiotic - Live organism that when ingest is believed to provide benefit to the host B. The Host-Parasite Relationship Figure 7. Common areas in the body that are susceptible to bacteria ★ Microbes living in and on body - Transient—temporary - Resident—always present A. Definition of Terms • Microbiota - community of microbes that live in and on an individual ; Can vary substantially between environmental sites and host riches in health and disease • Normal Flora - Microbiota Bio 125 – INTRODUCTION OF MEDICAL MICROBIOLOGY Page 5 of 10 UNIVERSITY OF THE PHILIPPINES BAGUIO COLLEGE OF SCIENCE DEPARTMENT OF BIOLOGY Streptococcus, Moxarella C. Normal Flora in the Gut Mouth and Nose GIT Urogenital Tract Streptococcus mutans, S. pneumoniae, S. auereus, Corynebacterium Bacteroides fragilis, enterococcus, E. coli Lactobacillus spp, Candida albicans 🕮 Research has shown that the “normal microbiota” provides a first line of defense against microbial pathogens, assist in digestion, play a role in toxin degradation, and contribute to maturation of the immune system.. B. TYPES OF HOSTS Figure 8. Different parts of the gut with bacteria present necessary for digestion and metabolism. 🕮 The term “normal microbial flora” denotes the population of microorganisms that inhabit the skin and mucous membranes of healthy normal persons. D. Human Microbiome Table 3. Different parts of the body with normal bacterial growth. PART Skin MICROORGANISM Staphylococcus aureus, S. epidermidis, Streptococcus spp, Propionibacterium acnes Eye Staphylococcus, Corynebacterium, a. Reservoir • A living organism or inanimate matter in which an infectious agent normally lives and multiplies. • For survival • May be: - Physical environment: contaminated water supply - Animals (insect vectors) - Other humans (AIDS, Hep B) • Zoonoses: infectious diseases that have vertebrate animal reservoirs; they are potentially transmissible to humans under natural conditions • Carrier: any person or animal that harbors a particular infectious agent without discernible clinical disease and serves as a potential source of infection ★ You literally carry it. Possible matransmit yung agent without even passing to that carrier. A carrier particularly does not show any signs of infection but harbors the agent of infection. Ex. Hepatitis A and B. • Vector ★ Term used for infection carried by insects or animals (zoonotic); can be mechanical or biological. • Source ★ The disease comes purely from the human or person itself. Bio 125 – INTRODUCTION OF MEDICAL MICROBIOLOGY Page 6 of 10 UNIVERSITY OF THE PHILIPPINES BAGUIO COLLEGE OF SCIENCE DEPARTMENT OF BIOLOGY personal protective equipment ★ hygiene, mask, gloves IX. THE INFECTIOUS AGENTS b. Carrier Table 4. Types of carrier-humans as carriers. TYPE OF CARRIER EXAMPLE Inapparent throughout Polio, Meningitis, -Asymptomatic all Hepatitis throughout, you have no recognizable clinical signs or symptoms, but you harbor or carry an etiologic agent Incubatory -you can be a spreader and be an agent of transmission (in short = nakakahawa ka) during the incubation of the disease Convalescent -when you are almost healed, that’s the time you can spread the disease Chronic -long-term / takes time (pangmatagalan) Chickenpox, Measles, Hepatitis Diphtheria, Hep B, Salmonella, Cholera Typhoid fever, Hep B C. FACTORS IN THE HOSTS a. Immunity ★ Passive - process of providing IgG antibodies to protect against infection; it gives immediate, but short- lived protection—several weeks to 3 or 4 months at most. Passive immunity is usually classified as natural or acquired: - Natural passive immunity: transfer of maternal tetanus antibody (mainly IgG) across the placenta - Acquired passive immunity: obtaining serum from immune individuals, pooling this, concentrating the immunoglobulin fraction and then injecting it to protect a susceptible person ★ Active - production of antibodies against a specific disease by the immune system; Process of exposing the body to an antigen to generate an adaptive immune response: the response takes days/weeks to develop but may be long lasting—even lifelong. - Naturally acquired through disease - Artificially acquired through vaccination A. TYPES OF INFECTIOUS AGENTS • Bacteria: TB, Shigellosis • Viruses and Rickettsia: AIDS, Hepatitis • Fungi: Candidiasis, Athlete’s foot • Protozoans: Amoebiasis, Giardiasis • Helminths: Schistosomiasis, Ascariasis 🕮 Viruses lack many of the attributes of cells, including the ability to replicate. Only when it infects a cell does a virus acquire the key attribute of a living system—reproduction. B. INTRINSIC PROPERTIES • Properties of infectious agents that do not need any interaction with host • Strains or isolates of a particular agent from different outbreaks, different geographic areas at different times may vary significantly in these intrinsic properties. a. Infectivity • The ability of an agent to enter and multiply in a susceptible host and produce infection • Can only be inferred by: the ease of spread in a population • High infectivity: Polio ★ Once the agent enters and multiply ang term dun ay infection. An infection may not necessarily lead to a visible disease. • Infectious Dose (ID) - Minimum number of organisms required to cause disease - Varies from organism to organism (10 for M. tuberculosis and 1000 for N. gonorrhoeae) - Less than ID—no disease - More than ID—may get more rapid onset • Binding to Host (Adhesion) - Bacteria: fimbriae, flagella - Viruses: receptors i.e. CD4 receptor - Protozoa: organelles for locomotion - Helminths: hooks and suckers b. Immunogenicity • Infection’s ability to produce specific immunity in the host e.g. measles b. Any form of protection Bio 125 – INTRODUCTION OF MEDICAL MICROBIOLOGY Page 7 of 10 UNIVERSITY OF THE PHILIPPINES BAGUIO COLLEGE OF SCIENCE DEPARTMENT OF BIOLOGY ★ Why is it important? Pag nagproproduce memory t-cells un immune system mo, pwedeng di ka na magkasakit. Unfortunately, may mga individuals na hindi nagproproduce ng memory within the immune system, Pwede magkaroon ng sakit ulit. May mga agents din that has a low immunogenicity. WHAT DOES IT MEAN? Di sya nadedetect ng immune system. Pasok sya, dirediretso sya, pwede sya magtago. One example: Papilloma virus. It’s so hard to detect. • Immunogenicity is measured by serologic surveys • Depends on: - Amount of antigen formed in the host - Agent’s ability to induce lifelong immunity c. Pathogenicity • Ability to produce clinically apparent illness in an infected population • High Pathogenicity: eg: measles • Pathogenicity = # of infected persons w/ disease Total number of infected persons d. Virulence • The extent to which severe disease is produced in a population with clinically manifest disease • Highly Virulent: eg: rabies ★ 100% ang case fatality rate, once you have it, babye ka na talaga  Figure 9. Difference between exotoxins and endotoxins. Table 5. Characteristics of exotoxins and endotoxins. CHARACTERISTIC Toxicity EXOTOXIN Toxic in minute Toxic in high doses amounts ENDOTOXIN Toxic in minute Toxic in high doses amounts Effects on the body Specific to a cell type Chemical composition Toxoid formulation Small proteins Systemic: Fever inflammation LPS of cell wall Cannot Immune response Fever stimulation Manner of release • Measures: • (CFR) Case Fatality Rate • Proportion of Severe Cases e. Toxigenicity • Capacity of an agent to produce a toxin or poison • Disease results from the toxin produced by the agent rather than from the agent itself • Endotoxin and exotoxin Endotoxin: Gram negative bacteria Exotoxin: Gram positive bacteria Can be converted to toxoid Stimulate antitoxins Usually not Secreted from live cell Does not Yes Released by cell during lysis C. DISEASE ACCORDING TO AGENTRELATED PROPERTIES DEGGREE INFECTIVIT Y PATHOGENECIT Y VIRULENCE High Measles, Chickenpox, Polio, Smallpox Rabies, Measles, Chickenpox, Smallpox, Common colds Rabies, TB, Leprosy, Smallpox Intermediat e Mumps, Rubella, Common colds Rubella, Mumps Poliomyelitis Low Very Low TB Leprosy TB, Polio Leprosy Measles Chickenpox , Rubella, Common colds Bio 125 – INTRODUCTION OF MEDICAL MICROBIOLOGY Page 8 of 10 UNIVERSITY OF THE PHILIPPINES BAGUIO COLLEGE OF SCIENCE DEPARTMENT OF BIOLOGY Modes of transmission: airborne, direct contact, droplet, fecal/oral, ingestion, fomites X. HOST-PARASITE RELATIONSHIP ★ So again, it’s always about balance. Relationships are not for humans only, it occurs in every being including microorganisms. Even microorganisms have relationships among themselves. Virus can kill bacteria (bacteriophage). If there’s an imbalance to the relationship, disease would occur. What will happen if we take in a lot of antibiotics? Mamatay yung mga good bacteria, matitira yung mga masasama. Then there would be a dysbiosis, abnormality or the disruption of microbiota resulting to further complication of the disease. A. Neutralism - 2 populations of Microbes found in a microecosystem w/o affecting one another; do not compete for nutrients B. Mutualism/ Symbiosis - Each organism benefits from the association - Found in the normal flora of humans - Dysbiosis: disruption of normal microflora C. Commensalism - 1 microbe benefits from the association but the other is not affected D. Antagonism - A microbe adversely affects the environment of another microbe ex: 1. Penicillum notatum vs. gram + cocci and bacilli 2. Lactobacillus casie (lactosin) vs. V. cholerae, Salmonella and Shigella E. Parasitism - 1 microbe lives in or on another microbe(host) w/c is commonly harmed ex: vibriophage vs. Vibrio Bedellovibrio bacteriovulus vs. E. coli F. Predation - 1 microbe ingests another microbe ex: Zooplankton feed on smaller algae and fungi - Found in Infections and Disease occurrence XI. TRANSMISSION TYPES OF TRANSMISSION a. Infection - The entry, development or multiplication of an infectious agent in the body tissues of man b. Infectious disease - A clinically manifest disease of man resulting from an infection c. Communicable Disease • An illness due to a specific infectious agent or its toxic products that arises through transmission from a reservoir to a susceptible host either directly or indirectly. ★Not all infectious disease is a communicable disease. Kelangan dumaan sa transmission kapag communicable disease. Pero pag infectious disease, it can be autonomous. d. Incubation Period • The time interval between initial contact with an infectious agent and the first appearance of symptoms associated with the infection e. Communicable Period • The time during which an infectious agent may be transferred from an infected host/reservoir to another susceptible host A. PORTAL OF ENTRY • Breaks in skin and mucous membranes • Natural openings: • GI, respiratory, GU tracts • Cross placenta: o Syphilis o Cytomegalovirus o Toxoplasma o Herpes o Rubella o Others (Hepa B, HIV) B. PORTAL OF EXIT • Secretions • Excretions • Discharges • Sloughed tissue C. GRADIENT OF INFECTION • Ranges from subclinical infection to severe clinical disease or even death a. Inapparent Infection Bio 125 – INTRODUCTION OF MEDICAL MICROBIOLOGY Page 9 of 10 UNIVERSITY OF THE PHILIPPINES BAGUIO COLLEGE OF SCIENCE DEPARTMENT OF BIOLOGY • Infection in a host without recognizable clinical signs or symptoms • Identifiable only by laboratory means b. Severe Disease • High rate of severe clinical manifestations • High case fatality rate (CFR) • High proportion of surviving patients with sequelae D. PATTERNS OF INFECTION a. Local infection: • Confined to specific site or tissue b. Systemic infection • Spreads to several sites or tissues c. Focal infection • Local infection that could spread o Head infections—blood supply o Toxemia d. Mixed infection • Polymicrobial, more than one organism involved. - Common in sepsis Ex: Dental caries - Organisms may show synergism e. Primary infection • Initial infection f. Secondary infection • Complicates primary infection: Opportunist g. Acute infection • Rapid, severe, short-lived h. Chronic infection • Persistent, slow progress i. Subacute infection • Onset less rapid than acute • Less persistent than chronic E. ACQUISITION OF DISEASE • Direct Transmission: skin or mucous membrane contact • between hosts: crossing placenta • Indirect Transmission o Vectors—living animal o Fomites—inanimate objects - microphone, door knobs, railings o Vehicle—inanimate material o Droplet nuclei o Aerosols (fine dust, moisture) • • SAMPLE CASE 48y/o woman CC: bloody diarrhea, abdominal cramps and fever while confined for the 6th day in the hospital. • Hx: She has been on levofloxacin for 5 days prior to admission and was started with clindamycin and augmentin upon admission. • Most likely Diagnosis? Pseudomembranous colitis • Pathophysiology of the disease? Dahil sa sunod sunod na antibiotics. Yung tatlong antibiotics would kill the normal microflora. So once you killed the good bacteria, there are bacteria na resistant sa antibiotics so they will persist, multiply and cause the disease. • Her condition is probably caused by which bacteria? Clostridium difficile • What do you need to do?  Stop the medications (antibiotics), supportive therapy. Pag di nawala, magbigay ng another antibiotic na papatayin yung C. difficile. Tapos introduce good bacteria. REFERENCE Baxter D. Active and passive immunity, vaccine types, excipients and licensing, Occupational Medicine, Volume 57, Issue 8, December 2007, Pages 552–556 Hara, Akihiro, Kazuaki Syutsubo, and Shigeaki Harayama. "Alcanivorax Which Prevails In Oilcontaminated Seawater Exhibits Broad Substrate Specificity For Alkane Degradation." Environmental Microbiology 5.9 (2003): 746-753 Hsu, P. D., Lander, E. S., & Zhang, F. (2014). Development and applications of CRISPR-Cas9 for genome engineering. Cell, 157(6), 12621278. Murray, P. R., Rosenthal, K. S., & Pfaller, M. A. (2015). Medical microbiology. Elsevier Health Sciences. Bio 125 – INTRODUCTION OF MEDICAL MICROBIOLOGY Page 10 of 10