Flashcards in Lecture 15 - Person to Person Diseases Deck (44)
What are the different transmission modes of person-to-person diseases?
What are the barriers to transmission and how do pathogens overcome these barriers?
-Gram positive bacteria, thick cell walls prevent dessication
How does airborne transmission occur?
travel through airborne particulates
-cause respiratory distress
-spread by sneezin, coughing, talking
How does transmission through direct contact occur?
physical contact or exposure
-many human carriers, often present in low numbers in normal human microflora
compromised immune system increases risk
How does sexual transmission occur?
Body fluids of urogenital tract transferred during sexual activity
Difficult to track or control
Passage to newborns in infected mothers
What are some examples of viral and bacterial airborne diseases?
-Pertussis (Whooping Cough)
What are the types of streptococcal diseases?
-Aerotolerant, Gram (+)
-= “Group A” Strep (GAS)
What is Epidemiology+Pathogenesis of Streptococcus pyogenes?
Present in Respiratory Microflora
What is the Epidemiology+Pathogenesis of Streptococcus pneumoniae?
-Present in Respiratory Microflora
-Lower Respiratory Tract
-Contribute to #1 Killer Worldwide
What is the pathogen and epidemiology+pathogenesis of pertussis?
-aerobic, gram (–)
Epidemiology + Pathogenesis
-adheres to upper respiratory tract
What is Pathogen, Epidemiology+Pathogenesis of tuberculosis?
-Gram (–), Bacillus Cells
What are some other Mycobacteria pathogens?
-Causes Classic TB Symptoms
-Eradicated with Pastuerization
What is the pathogen and epidemiology+pathogenesis of Measles?
-Negative strand RNA Virus
-Mostly affects children
-Enters Nose and Throat - Systemic Viremia
What is the the pathogen and epidemiology of the cold?
-Viral - numerous types
-most common infectious disease
What are the pathogen and epidemiology+pathogenesis for influenza?
-negative strand RNA virus
-infects upper respiratory tract
How can a pandemic occur?
-major change to virus antigen due to gene reassortment
-eg. bird virus infects pig and reasortment of virus occurs. Next humans are newly infected
What are some examples of influenza pandemics?
Swine flu in 2009
Spanish flue in 1918
What are some examples of direct-contact diseases?
What is the Pathogen and Epidemiology+Pathogenesis of staphylococcal infection?
-facultatively aerobic, Gram (+)
-microbiota of upper respiratory tract
-Variable mortality and unknown morbidity
-causes several diseases
What are the pathogen and Epidemiology+Pathogenesis for gastric ulcers?
-microaerophilic, Gram (–)
-But 80% of Hosts Are Asymptomatic
-May Lead to Gastric Cancer
-Attaches to Stomach and Duodenom Lining
What are the pathogen and the epidemiology+pathogenesis for hepatitis?
-numerous viruses, Hep A, B, C
-large decline due to vaccine
What are the pathogen and the epidemiology+pathogenesis for mononucleosis?
-Epstein-Barr Viruses, EBV
-dsDNA virus, member of herpes viral family
-exteremely low mortality
-over 90% worldwide morbidity
-infects salivary gland cells and B cells
What are the sexually transmitted diseases?
-gonorrhea vs syphilis
What is gonorrhea and syphilis?
Two common and treatable STDs
-higher incidence of gonorrhea
Why is there a higher incidence of gonorrhea?
1) Strain-Specific Aquired Immunity
-Repeated Reinfection Can Occur
2) Use of Oral Contraceptives
-Disrupt Vaginal Microflora
3) Mild Symptoms in Infected Women
-Many unaware of the disease
What are the Symptoms and the epidemiology for chlamydia?
-obligate intracellular bacterium
-most commonly reported STD in US
What is herpes?
-diverse, dsDNA virus group
-Herpes simplex I=cold sores
-Herpes simplex II=genital sores
What are the Pathogen and the Epidemiology+Pathogenesis for AIDS?
-Human Immunodeficiency Virus
-recognized in 1981
-Virus targets T cells and Macrophages using gp120 protein
-viral replication=immune cell death
-syncitia = fused Healthy +
Infected Host Cells which accelerates infection/destruction of host cells
What is the Symptoms+Diagnosis for Streptococcus Pyrogenes?
-Severe Sore Throat, Mild Fever
-Untreated, Leads to Scarlet Fever
-Immunofluorescence, ELISA, Throat Cultures