Pathogens Flashcards
What is a parasite
an organism or virus that lives in or on a host and benefits from them while harming them at the same time
What must a pathogen do in the host?
Enter, persist, and reproduce
What are the key players in human pathogens?
Bacteria (make up 40% of total) and then Fungi (20%)
which bacteria have a layer of lipopolysaccharides
gram-negative bacteria have an outer layer of lipopolysaccharides
of bacteria, archaea, and eukarya, which are pathogens
bacteria and eukarya
What are the main differences between microparasites and macroparasites
micro: live inside a host cell and replicate in the host(viruses, bacteria, fungi)
macro: leave the host after replicating (worms, arthropods)
What are the advantages of intracellular life
- access to nutrients in host cell
- hidden from phagocytes and antibodies
- hidden from antibiotics
advantages and disadvantage of extracellular life
- obtain nutrients from fluids between cells
- grow and reproduce freely
- spread rapidly
disadvantage: continuous exposure to host immune system
Which pathogen causes the least infections in humans
protozoa
Key features of Adenoviruses
Diseases: Pharynconjunctival fever, acute respiratory disease, gastroenteritis, mesenteric adenitis, intussusceptions, keratoconjunctavis, hepatitis, CNS disease
Transmission: respiratory droplets, eye to eye
Pathogenesis: Infect epithelium of respiratory tract and eyes/intestines
Treatment/prevention: Ribavirin and cidofovir, live oral vaccine
Staphylococcus aureus Characteristics
Diseases: Boils, skin sepsis, post-op wound infections, catheter infections, food bourne illnesses, endocarditis, TSS, pneumonia
Transmission: Humans skin and nose
Treatment: Penicillins, muprirocin, isolation
Candida albicans
Characteristics: fungus
Diseases: Thrush, candidiasis
Transmission: Normal part of skin, mouth, intestine
Treatment: Topical and oral antifungals, Amphotericin B, Fluconazole, itraconazole
Giardia intestinalis
Protozoan
Diseases: giardiasis
Transmission: fecal-oral
Pathogenisis: Diarrhea and impaired absorbtion
Treatment: Metronidazole, tinidazole
Genus Taenia
-Tapeworms
Diseases: (Taeniasis) Beef and pork tapeworms, cysticercosis (larval stages)
Transmission: Eating raw or undercooked meet from animals infected with larvae
Pathogenesis: Cysts in brain leads to neurological symptoms, adult worms symptomatic
Treatment: Niclosamide, praziquantel, albendazole
What organism can cause human infections and is a prokaryote?
Bacteria
What is candida albicans?
a eukaryotic pathogen that can infect humans
What class of organism is responsible for diseases like malaria and giardia?
Protozoa
Helminths are what kind of pathogen?
Worms
What is a characteristic that fungi, protozoa, and worms share?
They are eukaryotic organisms
What type of pathogen causes the most types of infections in humans?
bacteria
Describe the chromosome of a typical bacteria
circular and in the nucleoid
What is found in all prokaryotic cells?
ribosomes
What structure in prokaryotic cells contains the genetic material
nucleoid
What type of infection is commonly associated with staphylococcus aureus?
skin and soft tissue infections, such as impedigo, boils, and absesses
What is a common symptom of an adenovirus infection?
Cough and cold-like symptoms
Canadis albicans affects which area of the body most commonly?
Mouth, throat, genitals
What is the most common route of transmission for geiardia intestinalis?
Contaminated water or food
What is a key virulence factor of staphylococcus aureus that helps it evade a host’s immune system?
Its coagulase, which allows acteria to form clots
