Lecture 23 _bacterial path_-2 (2)

Page 1: Overview of the Plague (Black Death)

• The Black Death was a catastrophic plague outbreak in 1347 A.D.

• Significant societal impacts:

  • Dead bodies on streets, unattended livestock.

  • Extreme familial and societal breakdown (brother deserted brother).

• Caused the death of one third of Europe's population.

• Most severely impacted England compared to other European nations (Cartwright, 1991).

• Primary transmitters included Oriental Rat Fleas carried by black rats.

Page 2: Plague Transmission and Characteristics

• In the U.S., ground squirrels serve as reservoirs.

• Causative agent: Yersinia pestis (Gram-negative bacteria)

  • Transmission via:

    • Infected fleas, direct contact with infected animals/products, inhaling airborne droplets.

• Characteristic features include blackish areas on the skin due to subcutaneous hemorrhaging, leading to the term "Black Death".

• Occurrence: ~25 cases/year in the U.S. with a 15% death rate.

Page 3: Forms and Diagnosis of the Plague

• Three forms of plague:

  1. Bubonic: Features buboes (swollen lymph nodes); mortality rate 50-70% if untreated.

  2. Pneumonic: Almost 100% mortality; rapid progression within 12-24 hours, transmitted via respiratory droplets.

  3. Septicemic: Involves bacteria in the bloodstream.

• Bacteria can divide in blood and lymph; evades immune response via YOP secreted proteins.

• Diagnosis through microscopic examination, culturing, serological tests, PCR, and phage testing.

• Treatment: Streptomycin, chloramphenicol, tetracycline; good immunity upon recovery.

Page 4: Plague Transmission Pathways

• Direct Contact: Through infected carnivores (dogs, cats, coyotes).

• Airborne Transmission: Inhalation of droplets.

• Ingestion: Consuming infected animals.

• Urban reservoirs: Humans; Sylvatic reservoirs: Wild rodents.

• Vector: Rat flea bites human and vice versa.

Page 5: Overview of Q-fever

• Causative agent: Coxiella burnetii.

• Infects livestock through tick transmission; human infection primarily through inhaling contaminated dust from animal waste.

• Commonly affects slaughterhouse workers and farmers.

• Symptoms: Mild respiratory syndrome, severe headaches, muscle pain, fever (can last up to 1 month).

• Rarely fatal but can induce endocarditis (10% cases); hepatitis can occur pre-endocarditis.

• Diagnosis: Serological tests; Treatment includes chloramphenicol and tetracycline.

Page 6: Rocky Mountain Spotted Fever

• Causative agent: Rickettsia rickettsii, transmitted by ticks (wood ticks in Rocky Mountain states, dog ticks in eastern U.S.).

• Approximate cases: ~1000/year in the U.S.

• Symptoms: Headache, high fever, chills, skin rash (starting on ankles/wrists).

• Diagnosis via symptom observation, characteristic rash, serological tests.

• Treatment: Chloramphenicol and chlortetracycline.

Page 7: Anthrax Overview

• Highly contagious disease caused by Bacillus anthracis (Gram-positive, aerobic, spore-forming bacterium).

• Transmission: Direct contact with infected animals/products.

• Spores can survive decades in soil.

• Pathologies:

  • Cutaneous anthrax (most common, 95%) due to skin abrasion.

  • Pulmonary anthrax, associated with handling animal products (e.g., wool).

  • Gastrointestinal anthrax from undercooked meat.

• Cutaneous symptoms: Papule forming ulcer and eschar; untreated mortality rate ~20%.

• Treatment involves ciprofloxacin or doxycycline.

Page 8: Inhalation Anthrax Pathophysiology

• Inhalation causes spores to germinate in the alveoli, leading to lethal infection via bacteria entering the bloodstream.

• Toxins target macrophages (Mf), causing high mortality due to septic shock.

• Symptoms progress from mild respiratory illness to severe fever, hypothermia, or mortality if untreated.

Page 9: Anthrax Pathology and Photos

• Photos depict the malignant eschar caused by anthrax and the pathogenic mechanisms of anthrax toxin entry into macrophages.

Page 10: Gastrointestinal Anthrax

• Gastrointestinal anthrax presents with nausea, vomiting, and abdominal pain; follows ingestion of contaminated food.

• Global incidence: ~20,000-100,000 yearly; U.S.: <1 case/year in recent decades.

• Diagnosis via Gram-stain smear of lesions, CSF, or blood for encapsulated bacilli.

• Prevention through animal vaccination, at-risk human vaccination.

Page 11: Gas Gangrene Overview

• Caused by anaerobic bacteria Clostridium perfringens, C. novyi, C. septicum.

• Transmission through contaminated wounds; common in trauma and surgical patients.

• Symptoms: Severe pain, swelling, muscle necrosis; possible necessity for amputation.

• Treatment: Polyvalent antitoxin, tetracycline, penicillin, hyperbaric oxygen therapy.

Page 12: Leprosy Overview

• Caused by Mycobacterium leprae; humans and armadillos are reservoirs.

• 4000 cases/year in the U.S.; 14 million globally.

Page 13: Leprosy Pathophysiology and Symptoms

• Obligate intracellular parasite infects nerves, skin, and immune cells.

• Early: Slightly pigmented skin areas; advanced: significant tissue damage, loss of digits and facial features.

Page 14: Leprosy Statistics

• 2009 U.S. cases depicted by state; reveals transmission patterns and prevalence.

Page 15: Staphylococcal Infections

• Group of Gram-positive facultative anaerobes common in normal flora.

• Pathologies include boils, carbuncles, and more severe infections.

• Coagulase-positive strains (S. aureus) are more virulent.

• Transmitted through various routes, infecting diverse tissues.

Page 16: Staphylococcal Skin Infections

• Various skin infections visualized, including folliculitis and scalded skin syndrome.

Page 17: Staphylococcal Enzymes and Toxins

• Overview of various enzymes and their physiological impacts (e.g., breaking down substances or causing inflammation).

Page 18: Gonorrhea Overview

• Caused by Neisseria gonorrhoeae; sexually transmitted affecting mucous membranes.

• Significant cases annually in the U.S.

• Symptoms: Urethral pus in males, mild discharge in females; PID leading to sterility.

Page 19: Chlamydia Overview

• Chlamydia trachomatis causes various infections, notably inclusion conjunctivitis in newborns.

• Urethritis in adults; standard diagnosis and treatment outlined.

Page 20: Lymphogranuloma Venereum

• Caused by serotypes L1-L3 of Chlamydia trachomatis.

• Characterized by progressive symptoms and possible severe complications if untreated.

Page 21: Trachoma Overview

• Caused by serotypes A-C of Chlamydia trachomatis; leading cause of blindness worldwide.

• Disease impacts children but is uncommon in the U.S.

Page 22: Non-Gonococcal Urethritis

• Chlamydia can result in significant morbidity, particularly in women, leading to infertility.

Page 23: Syphilis Overview

• Caused by Treponema pallidum; manifests in venereal and congenital forms.

• Characteristic three stages of the disease: primary (chancre), secondary (rash), tertiary (gummas).

Page 24: Syphilis Diagnosis and Treatment

• Diagnosis using serological tests; Treatment involves benzathine penicillin G; risks of reinfection noted.

Page 25: Research on Syphilis

• Ongoing research into syphilis, including methods for single-cell transcriptional studies.

Page 26: Overview of STDs

• Summary table of various STDs, their causative agents, comments, and treatments outlined.

Page 27: Additional STDs

• Continued breakdown of other bacterial STDs and their treatments in tabular format.

Page 28: Other Contact Diseases

• Brief mention of additional notable contact diseases not covered in detail.

Page 29: Bacteria in Diarrheal Illnesses

• Overview table of bacteria responsible for food poisoning, emphasizing epidemiology and clinical features.

Page 30: Pathogenesis of Food Poisoning Bacteria

• Detailed descriptions of foodborne pathogens, their mechanisms, and clinical reviews outlined.

Page 31: Continued Pathogenesis of Food Poisoning

• Further continued summary focusing on pathogenic mechanisms and expected clinical symptoms.

Page 32: More on Bacterial Diarrheas

• Detailed notes regarding specific bacteria involved, clinical presentation, and treatment guidelines.

Page 33: Biofilm Surfaces

• Overview of surfaces where biofilms can develop and the implications for infection.

Page 34: Biofilm Formation

• Explanation of biofilm growth phases and process dynamics.

Page 35: Glycocalyx or Biofilm

• Discussion on biofilm properties, significance, and its implications for treatment of chronic infections.

Page 36: P. aeruginosa Eye Infection

• Overview provided in context to biofilm-related complications in ocular infections.

Page 37: Mixed Biofilm Infections

• Mention of surgical concerns with biofilm infections post-operation.

Page 38: Biofilm Impact on Marine Environment

• Biofilm consequences for ships, including increased costs and maintenance issues.

Page 39: Chemical Structures

• Presentation of molecular structures relevant to the subject matter.

Page 40: Dental Plaque Formation

• Description of the formation of dental plaque, and associated biochemical factors in the development of caries.

Page 41: Advanced Dental Plaque Information

• Further insight into dental plaque components and biofilm establishment processes.

Page 42: Periodontal Disease

• Visual depiction of periodontal disease and its clinical implications.

Page 43: Biofilm Functional Genomics

• Highlights importance of understanding bacterial metabolism and behavior within biofilm contexts.

Page 44: Pathogenic Protozoa Overview

• Table outlining various pathogenic protozoa with host and disease associations.

Page 45: Leishmaniasis Overview

• Brief mention of leishmaniasis details, further context needed in studies.

Page 46: Malaria Patterns

• Map displaying regions impacted by malaria transmission dynamics.

Page 47: Water Purification Methods

• Overview of techniques and processes involved in water purification, including disinfection methods.

Page 48: Rapid Sand Filtering

• Description of the mechanics involved in rapid sand filtering for water treatment.

Page 49: Coliform Bacteria

• Definitions and distinctions between total and fecal coliforms and their importance in water quality assessment.

Page 50: U.S. Drinking Water Standards

• Table indicating allowable contaminant levels for safe drinking water and regulations enforced by the EPA.

Page 51: Waste-water Treatment Overview

• Overview of waste-water treatment processes focusing on carbon removal methods.

Page 52: Treatment Steps Table

• Tables summarizing major steps involved in waste-water treatment.

Page 53: Secondary Treatment Explored

• Examination of processes within secondary treatment for effective waste management.

Page 54: Extended Aeration

• Overview of the importance of extended aeration for microbial waste treatment.

Page 55: Importance of Proper Floc Formation

• Details about floc formation and impacts of improper aeration techniques.

Page 56: Anaerobic Digestion Processes

• Explanation of anaerobic digestion and end products.

Page 57: Goals of Tertiary Treatment

• Overview of objectives for removing nitrogen and phosphate in water purification.

Page 58: Ground Water Filtration

• Characteristics of effective natural ground water filtration systems.

Page 59: Constructed Wetland Treatment Overview

• Description of constructed wetlands for wastewater treatment and nutrient removal.

Page 60: Aquaponic Systems

• Process of aquaponics as a method of biological waste management.

Page 61: Medicinal Mushrooms Overview

• List of notable medicinal mushrooms and their effective properties outlined.

Page 62: Medicinal Properties of Mushrooms

• Summary of multifaceted effects of mushrooms, including therapeutic properties.

Page 63: Lion's Mane Mushroom Details

• Additional insight and studies on Lion's Mane mushroom and its benefits.

Page 64: References on Lion's Mane

• Citation list for further exploration of Lion's Mane research and medicinal effects.