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virus life cycle

1. adsorption(attachment) 2. penetration 3. uncoating 4. synthesis 5. assembly 6. release

virus structure

capsids + nucleic acid + envelopes

fastidious, non-fastidious

require specific nutrients

halophilic, non-halophilic

prefer higher concentration of salt

protozoa

unicellular eukaryotic, parasite

helminth

multicellular eukaryotic, not all are parasites, some live free in soil and water

fungi

eukaryotic

Obligate aerobes

need o2 to grow

Obligate anaerobes

need o2 to survive

Facultative anaerobes

o2 doesnt affect

Aerotolerant anaerobes

no need o2

Microaerophiles

need small amount of o2

How is infection established

survive inside phagocyte, suppress interferon production, antigenic variation (mutate and let antibody cant recognise)

Vertical transmission

transmit from parent to offspring via the ovum, sprem, or milk

Horizontal transmission

from one infected individual to another (direct: involve very close proximity between two host, indirect: infectious agent pass from an infected host to an intermediate conveyor to another host, vector: mechanical/biological)

mass spectrometry

used to analyse a protein fingerprint, identify according to their mass-to-charge ratio, detect antibiotic susceptibilities

pros and cons of live vaccine

enough replication to induce a strong immune response, booster dose may not be required, risk to immunocompromised individuals

pros and cons of non-live vaccine

no risk to immunocompromised individuals, induce a weaker immune response, booster dose may be required

purpose of vaccine

prevent clinical manifestations of infection, protect against asymptomatic infection or colonization

purpose of booster

maintain the antibody levels in the circulation sufficient for protection, improve the affinity of the antibody by the antibody affinity maturation

Characteristics of the ideal antimicrobial drug

toxic to the microbe but nontoxic to human, microbicidal rather than microbistatic, remain active in tissue and body fluids

Factors to consider before antimicrobial therpay

identity of the microorganism, degree of the microorganism's susceptibility to various drugs, overall medical condition of the patients

Mechanisms of antibiotic

1. inhibit cell wall synthesis 2. inhibit nucleic acid structural and function 3. inhibit protein synthesis 4. interfere with cytoplasmic membrane structure and function 5. inhibit folic acid synthesis

Mechanisms of antiviral drugs

1. inhibit of viral entry 2. inhibit of viral nucleic acid synthesis 3. inhibit of viral release

second line of defense: phagocytosis, antimicrobial products

ingest and eliminate microbes, interferons: prevent translation of viral proteins

how to collect body fluids

must be taken by sterile needle aspiration

drug susceptibility testing example

Kirby-Bauer test (zone), Tube dilution test (minimum inhibitory concentration MIC)

Ct value

the smaller the ct value, the larger the quantity of the sample

Vaccine-induced protection

need to meet the protective antibody level to prevent infection

Disadvantages of vaccines

antibody-dependent enhancement (ADE), original antigenic sin

Common antibiotics that hv allergic responses

penicillin

mechanisms of drug resistance

synthesis new enzymes and inactive the drug, immediately eliminate the drug

Vaginitis and vaginosis

Candida albicans

Neonatal meningitis

Escherichia coli

Legionnaires' disease

Legionella pneumophila

Tuberculosis

Mycobacterium tuberculosis

Gonorrhea

Neisseria gonorrhoeae

Folliculitis / Impetigo / SSSS

Staphylococcus aureus

Cellulitis / Pharyngitis

Streptococcus pyogenes