Microbiology Final

Kent State Spring 2024 Professor Leff

Influenza

RNA virus belonging to the Orthomyxoviridae family

Influenza Transmission

Spread through respiratory droplets when an infected person coughs, sneezes, or talks

HIV Viral Structure

Retrovirus with an outer envelope studded with glycoproteins, central core containing the viral RNA genome

HIV Characteristics

Infects CD4-positive T cells and macrophages, > immune system dysfunction.
Fast development hard to make vaccine

HIV Origin

non-human primates in Central and West Africa, Cross-species transmission to humans occurred through hunting and handling of infected animal carcasses

HIV Transmission

sexual contact, exposure to infected blood, and from mother to child during childbirth or breastfeeding

HIV Targets what type of cells?

CD4-positive T cells, macrophages, and dendritic cells in the immune system

HIV Symptoms

Acute = present with flu-like symptoms
Advanced = immunodeficiency and various opportunistic infections and malignancies

HIV Treatment

Antiretroviral therapy (ART), consisting of a combination of drugs that target different stages of the viral life cycle

HIV Prevention

safe sex practices, needle exchange programs, pre-exposure prophylaxis (PrEP)

HBV (Hepatitis B Virus) Transmission

Exposure to infectious blood, semen, and other body fluids, as well as from mother to child during childbirth

Hep B (HBV) Complications

Liver cirrhosis, liver cancer, and liver failure

Hep B (HBV) Symptoms

Jaundice, fatigue, abdominal pain, nausea, and vomiting

Hep B (HBV) have a vaccine available?

A recombinant vaccine is available

HAV (Hepatitis A Virus) Transmission

fecal-oral route, often via contaminated water or food

HAV (Hepatitis A Virus) Complications

Acute = liver inflammation
does not typically progress to chronic infection

HAV (Hepatitis A Virus) Symptoms

Fever, fatigue, loss of appetite, nausea, and jaundice

Does HAV (Hepatitis A Virus) Have a prevention vaccine?

A vaccine is available to prevent infection

HCV (Hepatitis C Virus) Transmission

Exposure to infected blood, such as through sharing of needles

HCV (Hepatitis C Virus) Complications

Chronic = Liver cirrhosis, liver cancer, and liver failure

HCV (Hepatitis C Virus) Symptoms

May be asymptomatic
fatigue, jaundice, and abdominal pain

Does HCV (Hepatitis C Virus) have a vaccine?

no vaccine available

Staphylococcus

Genus of microorganisms with multiple species

Gram-positive Cocci (3)

Staphylococcus
Streptococcus
Enterococcus

Staphylococcus Metabolism

Facultative anaerobes, can grow in various oxygen levels

Staph causes what % Nosocomial infections

about 25%

Staphylococcus aureus

Most virulent staph

Coagulase-based staphylococci

Not as virulent, can be harmless microflora

Methicillin-resistant Staphylococcus aureus

S. aureus strain with multiple antibiotic resistances

Staphylococcus is Fastidious

Needs growth factors or vitamins, limited livable environments, usually needs host

Streptococcus pyogenes

Bacteria causing skin infections, strep throat, puerperal fever, scarlet fever, rheumatic fever,

Rheumatic fever

Autoimmune response to Strep Pyogenes causing joint and heart damage

Scarlet fever

Strep Pyogenes infection with high fever and red rash

Pneumococcal pneumonia

Lung infection caused by Streptococcus pneumoniae

Otitis media

Ear infection, common in infants and young children, caused by Strep Pneumonia

Enterococcus

Gram-positive
Bacterial microflora in intestinal tracts, causes UTIs and bacteremia (bacteria in blood)

Gram-negative Cocci (1)

Neisseria (Gonorrhea + meningococcal meningitis)

Gonococcal ophthalmia

Eye infection in infants born to mothers who have gonorrhoeae

Neisseria meningitidis

Causes meningococcal meningitis, a serious infection. Bacteria / endotoxin invade bloodstream

Mycobacterium Tuberculosis

Slow-growing bacteria causing tuberculosis, with unique cell wall composition.

Primary Stage of Tuberculosis

Initial infection stage, often asymptomatic.

Secondary Stage of Tuberculosis

Reactivation stage with severe lung damage and symptoms like coughing.

Extra-pulmonary Stage of Tuberculosis

Spread of bacteria to organs like bones, kidneys, and nervous tissue.

Pseudomonads

Gram-negative, rod-shaped bacteria found in the environment

Pseudomonas aeruginosa

Pseudomonads species causing infections like UTIs, especially in hospital settings

Pseudomonas Exoenzyme Production Why?

Degrade connective tissue and use the residuals as nutrients

Enteric Bacteria

Rod-shaped cells found in the gastrointestinal tract causes intestinal upset and UTI’s

Strict Pathogens

Bacteria causing disease in healthy individuals without predisposing factors

Lyme Disease

Caused by Borrelia

Influenza

Acute respiratory infection affecting warm-blooded vertebrates

Neuraminidase

Spike protein aiding virus penetration through mucus in the respiratory tract.

Hemagglutinidase

Spike protein assisting in the initial attachment of the virus to host cells.

Antigenic drift

Mutation in RNA causing variations in the influenza virus.

Influenza A

Most severe type causing coughing and breathlessness in infected individuals.

Influenza B and C

Types with less severe symptoms compared to Influenza A.

Spikes (Virus)

Proteins protruding from the virus envelope for host cell attachment.

Influenza Transmission

Spread through droplets or aerosols, especially in cold weather.

Cocci bacteria of medical importance

Staphylococcus, Streptococcus, Enterococcus, Neisseria

Respiratory tract Staphylococcus

S. aureus

T/F Staphylococcus bacteria can cause every type of infection (blood, respiratory, urinary tract, surgical wound, soft tissues, and gastrointestinal)

False, everything but gastrointestinal infections

Staphylococcus

Genus of Gram-positive bacteria
S. aureus and MRSA.

Streptococcus

Genus of Gram-positive bacteria,
S. pyogenes and S. pneumoniae.

Streptococcus pyogenes

Bacterium causing various diseases like strep throat and skin infections.

Streptococcus pneumoniae

Bacterium causing pneumonia and meningitis.

Enterococcus

Gram-positive bacteria,
opportunistic pathogens.

Neisseria

Genus of Gram-negative bacteria
N. gonorrhoeae and N. meningitidis.

Neisseria meningitidis

Bacterium causing meningococcal meningitis.

Clostridium

Gram-positive, spore-forming, anaerobic bacteria.

Gas Gangrene

Infection by Clostridium species in deep wounds. (turns green and creates gas inside wound from bacteria growing)

Tetanus

A disease caused by the bacterium Clostridium tetani,
characterized by painful spastic paralysis of skeletal muscles due to a potent neurotoxin called tetanospasmin.

Botulism

A condition resulting from ingesting the neurotoxin produced by Clostridium botulinum, leads to flaccid paralysis of skeletal muscles and potentially fatal respiratory failure.
found in improperly canned food where spores germinate and produce the toxin

Mycobacterium

A genus of Gram-positive aerobic rods known for slow growth, high lipid content in the cell wall, and including species like Mycobacterium tuberculosis, the causative agent of tuberculosis.

Pseudomonads

Gram-negative bacilli
some cause infections in humans, like UTI and pneumonia.

Enteric Bacteria

Gram-negative facultative anaerobes of the Enterobacteriaceae family, such as Escherichia coli, Klebsiella sp., and Enterobacter sp.,
Can be microflora but also opportunistic pathogens

Salmonella

Bacteria causing typhoid fever and non-typhoid salmonellosis

Yersinia pestis

Bacteria causing the plague

Typhoid Fever

Disease caused by Salmonella typhi, transmitted via fecal-oral route

Septicemic Plague

Form of the plague affecting the bloodstream

Pneumonic Plague

Form of the plague affecting the lungs

Borrelia

Genus of bacteria causing Lyme disease

Lyme Disease

Infection caused by Borrelia burgdorferi transmitted by ticks

Poliomyelitis

Viral disease affecting the nervous system

Neuraminidase

Enzyme used by influenza virus to penetrate host cells

Hemagglutinin

Protein used by influenza virus for adherence and penetration of host cells

Bacterial Pneumonia

A possible secondary infection that can occur after influenza due to damage and immune compromise

SARS-CoV

Severe Acute Respiratory Syndrome coronavirus, which caused a global outbreak in 2002-2003.

MERS-CoV

Middle East Respiratory Syndrome coronavirus, identified in 2012

SARS-CoV-2

The coronavirus responsible for the Covid-19 pandemic, first identified in December 2019.

Gram-positive Bacilli

Clostridium
Mycobacterium

Gram Negative Bacilli (1)

Pseudomonads (Pseudomonas Aeruginosa)