microbiology module 5 FINAL EXAM

vaccine material

vaccine material

antigens that subsitute fo the pahtogens that would cause disease

killed bacteria or inactivated virus...

cannot cause infection

attenutated bacteria or viruses

attenuated means alive but "weakened"(credit to Pasteur) cannot acuse cause disease but are immunogenic(cause immune system to produce antibodies)

accellar/antigenic fragments

antigens from cells or viruses

toxoid

inactivated toxin but still antigenic

purified polysaccharide

polysaccharide conjugated with protein

(protein strengthens immune response)

principle vaccines used in the U.S. to present bacterial diseases in humans...↓

DTap

Diptheria

purified diptheria toxoid

pertussis

acellular fragments of purified from Bordetella pertussis(~12Ag) kills babies

tetanus

purified tetanus toxoid

meningococcal meningitis

purified polysaccharide from N. meningitidis

Haemophilus influenza type b meningitis (HiB vaccine) is made of...

polysaccharides conjugated with proteins

Pneumococcal conjugate vaccine :

Streptococcus pneumoniae antigens conjugated

Measles vaccine is...

attenuated virus

what is the MMR vaccine for

Measles mumps and rubella

mumps vaccine is...

attenuated virus

rubella vaccine is...

attenuated virus

chicken pox vaccine is...

attenuated virus(shingles----Herpes zoster = same)

human papilloma virus(HPV) vaccine is...

Ag fragments

human papilloma virus(HPV) vaccine prevents

cancers later in life

hepatitis A

inactivated virus

hepatitis B

antigenic fragments(recombinant vaccine)

poliomyelitis vaccine is...

inactivated virus(Salk vaccine)(Sabin is attenuated virus vaccine another version but not as safe)

SARS----CoV----2 vaccine is a...

RNA vaccine

how many vaccinations and boosters are recommended in the first year of life?

22 vaccinations or boosters

passive immunization

someones else's preformed anitbodies, protiecion developing your onw antidbodies

how to people with antibodies give it to other people?

take their blood through titers, gamma globulin (antibodies from a pooled serum) and give to others.

advantages of passive immunization

• protections from immunocompromised(who can't get vaccines)

• immediate protecion

• temporary protection while immunity develops

what are some disadvantages of passive immunization?

• serum sickness (animal preperations)

• no lasting immunity

Immunoglobulin g (ImG)

get from your mother

naturally acquired active immunity

disease or Normal exposure(antibody)

naturally acquired passive immunity

placenta/breast milk(mother to child)

artificially acquired active immunity

vaccines

artificially acquired passive immunity

gamma globulin injection(get antibodies from someone else who already created it in blood)

immunological disorders

response to antigens(allergens) that leads to damage

what are the types of reactions?(4 of them)↓

i. anaphylactic

ii. cytotoxic

iii. immune complex

iv. cell mediated (or delayed type)

type i. anaphylaxis

first exposure to sensitizing antigen causes B cells, with help of TH cells to make IgE, IgE(receptor and ability to bind to mast and basophils), IgE binds to mast cells(or basophils) at the antibodies constant region, on later exposure antigen bind to IgE at the antigen----binding site, stimulating the mast cell to degranulate, release of inflammatory mediator, including histamines prostaglandins and leukotrienes, that cause an allergic response.

type i. anaphylaxis

• allergy development(immunization----sensitized to allergen produces IgE antibody

• cellular response (IgE binds to Fc receptor---- mast cells basophils)

• antigen binds IgE

• cross----linking of IgE antibodies

• degranulation---- release of chemical mediators, histamine, prostaglandins, leukotrienes

• symptoms ---- smooth muscle contraction(bronchia) vascular permeability, swelling edema, respiratory distress, death

type ii. Cytotoxic Reactions

• cytotoxic reactions involve IgG or IgM antibodies and complement activation

• cell lysis or damage by macrophages

hemolytic disease of a newborn Rh factors "blue baby"

• Rh+ father

• Rh---- mother carrying Rh+ fetus, Rh antigens from the developing fetus can enter the mothers blood during delivery

• in response to the fetal Rh antigens the other will produce antibodies that are anti----Rh antibodies

• if the woman becomes pregnant with another Rh+ fetus, her anti----Rh antibodies will cross the placenta and damage the fetal RBC

what type of Ig affects the baby's blood?

iii. immune complex----mediated hypersensitivity

• systemic lupus erythematosus (SLE)

• antibodies to cell nucleus components

• deposits in many areas

  • kidneys‒ most common

  • skin‒ causes butterfly rash on face(lupus wolf)

  • joints‒arthritis

  • brain‒mental

rheumatoid arthritis

• antibodies to rheumatoid factor

• chronic joint inflammation/damage

type iii. immune complex-mediated hypersensitivity

• immune complexes are deposited in wall of blood vessel

• presense of immune complexes activates complement and attracts inflammatory cell such as neutrophils

• enzymes released from neutrophils cause damage to endothelial cells of basement membrane

type iv. cell----mediated

• t cell response - delayed(12-48 hrs after exposure) not antibody mediated

• first exposure- t cells sensitized, cell proliferate ‒ T clone increases

• second exposure ‒ t cells activated by antigen, release lymphokines, stimulate macrophages and inflammatory response(symptoms)

resin of poison ivy and skin protein reaction

body recognizes non----self and t cell come and attack skin proteins(dermatitis)

Mantoux tuberculin skin test involves...

• purified protein derivative(antigen) extracted from Tb cell

• PPD intradermally

• a previous infection or exposure to Tb= sensitivity to Td cells

• a positive reaction is Type IV hypersensitivity, once positive always positive if you want to check for infection use chest x-ray, this test is for IMMUNITY.

how to check for active infection of Tb?

use chest x----ray to check for active infection

The mRNA molecules used in the Moderna (Mod) and the Pfizer----BioNTech (P----Tech) vaccines contain genetic information for what SARS----CoV----2 viral component?

spike protein

How is the fragile mRNA molecule in the vaccines physically protected from destruction (in the vials and after the IM injection)?

a lipid----based nanoparticle surrounds the mRNA

How is the mRNA in the Johnson and Johnson vaccine protected?

it's inside a harmless cold virus protein shell (aka, the capsid ---- remenber that term?)

After injection into the body, all 3 vaccines stimulate the activity of what type of immune cells to create immunity?

• Antigen processing cells (APC)

• Helper T-cells

• B-cells

• Cytotoxic T-cells

What "type" of hypersensitivity is the human reaction to poison ivy?

Type IV

What component of poison ivy causes the itchy skin reaction?

An allergen in the sap called urushiol

What "chemical mediator" is released during the reaction to poison ivy, and where is the chemical active?

IL----33, the skin's nerve cells

In the research trials, how was the itch response diminished or eliminated in the test mice?

Antibodies against the active chemical mediator and antibodies against the nerve receptors prevented the itch

Approximately how many vaccines and antiviral treatments are currently in development to reduce hospitalizations due to the SARS----CoV2 virus?

more than 80

If antibiotics are known not to be effective against virus infections why would there be a need to use antibiotics with this virus?

Many COVID infections can lead to secondary bacterial pneumonia, requiring effective antibiotic treatment

Why are hospitals discouraged from using new antibiotics from treating antibiotic resistant infections associated with serious COVID infections?

The hospitals don't get reimbursed for using the sometimes very expensive new antibiotics

How does author propose to help hospitals use the most effective antibiotic available to treat patients with bacterial pneumonia?

Allow reimbursement for the use of the most effective antibiotic, and provide incentives for new antibiotic research and development

T/F : Cases of scarlet fever have been rising in many countries around the globe.

true

The causative agent of Scarlet Fever is

Streptococcus pyogenes

The causative agent of Scarlet fever can also cause

• Impetogo

• Strep throat

• pneumonia

• flesh-eating disease

The cause of Scarlet fever is most often spread by

Saliva droplets released by coughing and sneezing

Serious complications that can arise due to Scarlet fever infection include

Rheumatic fever

Scarlet fever is successfully treated with

antibiotics

The 3 viruses in the "tripledemic" are

• respiratory syncytial virus

• Influenzavirus

• SARS-CoV-2

The ILI epidemiology data show that outpatient visits for respiratory illness in the Fall of 2022...

show a much earlier increase than most of the past 5 years.

How does the flu season in 2020----21 compare to nearly all the other recent flu seasons?

Nearly non----existent, hardly any flu symptom visits to Doctors' offices.

These tripledemic viruses increase the risk for co----infection. What is meant by "co----infection"?

An individual can be infected with 2 or more of these viruses.

This Salmonella outbreak is linked to Honey Smacks cereal. The cereal would be considered as the...

Vehicle

The outbreak due to eating the cereal consisted of

73 cases, 24 hospitalizations, no deaths

The FDA recommends this if you have purchased Honey Smacks

Do not eat any of the cereal and discard any leftover cereal, or return it to the store.

Symptoms of Salmonella infection would include...

Vomiting, diarrhea, fever

How did the Salmonella most likely get into the cereal manufacturing plant?

From Salmonella contaminated ingredients or from an ill worker

Compared to several years ago the incidence of Salmonella and E. coli infections today is

lower than past years.

According to the CDC how does the incidence of E.coli food borne illness compare to the Salmonella illness rate?

Much higher rate for Salmonella

T/F : The recent case of polio in NY involved a person who was previously vaccinated against the poliovirus.

false

What danger did this individual case have for the general population in his area?

No danger for fully vaccinated children and adults ---- getting the recommended doses of polio vaccine is highly protective.

Globally, the recent trend in vaccination rates for various diseases has been...

---- going down for several serious diseases, including polio and measles

T/F : Vaccine hesitancy, i.e. not getting recommended vaccinations, can affect overall public health. Since this mainly concerns COVID vaccines, routine childhood vaccinations have not been influenced by anti----vaxxers.

false

Polio, originating and spreading in the US population, was eliminated in the US because of its high vaccination acceptance. What year was polio considered eradicated in the US?

1979

How is the poliovirus most commonly transmitted?

Fecal----oral ---- usually contaminated food or water.

antibiotics are made of…

plants+microbes

the "Magic Bullet" concept...

• bullet kills only selected pathogen and not the innocent bystander(host cells)

• Paul Ehrilich

• #606 cured Trypanosomal infection in mice(test) then use on syphilis patient(worked on most but killed other)

the magic bullet was developed by

Paul Ehrlich in early 1900's a Germán organic chemist tested 100s of organic arsenic cmpds

modern term for "magic bullet"

selective toxicity

theraputic index is

the max dose that is not toxic to patient divided by min effective dose against pathogen

therapeutic index example equation 10mg/kg effective does is 2m/kg therapeutic index is...

TI=5

narrow spectrum of microbial activity

drugs that affect a narrow rang of microbial types

broad----spectrum antibiotics

affect a broad range of Gram----positive and Gram----negative bacteria

superinfection

overgrowth of normal microbiota that is resistant to antibiotics

in 1928 Fleming discovered

penicillin produced by Penicillium(a mold)

1940 Howard Florey and Ernst Chain performed

first clinical trials of penicillium extracted and turned into medicine

when penicillin is around the bacterial cell...

lyses because the penicillin weakens the cell wall and the cell explodes

what bacteria is resistant to penicillin?

Staphylococcus aureus

Major actions modes of antibacterial drugs(list 5)

• inhibition of cell wall synthesis(penicillin, cephalosporins bacitracin, vancomycin)

• inhibition of proteins synthesis( chloramphenicol, erythromycin, tetracyclines, streptomycin)

• inhibition of nucleic acid replication and transcription : quinolones, rifampin

• injury to plasma membranes: polymyxin B

• inhibition of essential metabolite synthesis(sulfanilamide, trimethoprim)

the original antibiotic prescription for a bacterial infection "stopped working" and you are prescribed a new one. Explain why the first one didn't work?

the bacteria developed resistance to the antibiotic and was no longer susceptible

(not counting antibiotic allergies) Can a person ever become "immune" to an antibiotic so that it no longer works?

no, the bacteria that becomes genetically or metabolically resistant to the antibiotic NOT YOU

antibiotic resistance mechanisms(list 3)

• resistance genes

• cell mutation event

• multiple resistance