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Microbiology
Bacteria, Viruses and Yeast/Fungi
…and some drugs and stuff
Sarah Watson, 2010
Bacteria
Pathogenicity Factors
1. Adherence factors
Allow adherence to body surfaces
2. Invasins
Promote tissue invasion
3. Endotox...
Which cause disease?
1. Classics
E.g. Mycobacterium tuberculosis
2. Commensals
E.g. Escherichia coli
3. Opportunists
E.g. ...
Gram Staining
Blue-black/violet Pink/red
Gram Positive
Bacilli
• Clostridium
– botulinum
– difficile
– perfringens
– tetani, etc.
• Bacillus
– anthracis (anthrax)
...
Gram Positive Bacilli
Clostridium difficile
Gram Positive Cocci
Stapylococcus aureus
Streptococcus pyogenes
Streptococcus pneumoniae
Clostridium
• Food poisoning (C.
perfringens)
• Diarrhoea (C. diff.)
• Botulism (C. botulinum)
• Tetanus (C. tetani)
• Sep...
Bacillus anthracis
• Causes anthrax
• 3 types:
– Cutaneous
• Localised inflammatory black necrotic lesion (eschar)
• If le...
Staph. aureus (MSSA/MRSA)
• Cellulitis
• Venous leg ulcer
• Infected cannulation site
• HAP (MRSA)
• Sepsis of unknown sou...
Strep.
• Cellulitis
• Necrotizing fasciitis
• Venous leg ulcers
• Acute otitis media (Strep. pneumoniae)
• Pharyngitis (St...
Gram Negative
Bacilli
• Campylobacter jejuni
• ‘Coliforms’
• Escherichia coli
• Helicobacter pylori
• Klebsiella spp.
– pn...
Gram Negative Bacilli
E. coli
H. pylori
Gram Negative Bacilli (contd.)
Pseudomonas aeruginosa Salmonella typhi
Gram Negative Cocci
Neisseria meningitidis
Gram Negative Coccobacilli
Haemophilus influenzae
Mycobacterium tuberculosis
• Campylobacter jejuni/enteritis
– Diarrhoea
• ‘Coliforms’ (inc. ESBLs)
– HAP
– Cystitis
– Pyelonephritis
– Abdominal seps...
• N. gonorrhoeae
– Gonorrhoea
– Vaginal discharge
– Urethritis
– PID
• N. meningitidis
– Meningitis
– Sepsis of unknown
so...
Meningitis – common causative
organisms
• Neonates
– Streptococcus pneumoniae
(pneumococcal meningitis)
– Escherichia coli...
Gram Null
• Chlamydia trachomatis
• Chlamydophila pneumoniae (Chlamydia)
Elementary body
Reticulate body
Summary – Bacteria Types
Gram +ve
• Coccus
– Staph and Strep
• Bacillus
– Clostridium
– Listeria
– (anthracis)
Gram -ve
• ...
Antibiotics - types
• Penicillins
– Inc. co-amoxiclav
• Cephalosporins
– Cefotaxime
– Ceftriaxone
– Cefalexin
• Macrolides...
Penicillins
• Bacteriocidal
• β-lactam (ring) activity
– Inhibits peptidoglycan cross-linking
• Usually active against Gra...
Cephalosporins
• Bacteriocidal
• β-lactam activity
• Less susceptible to penicillinases
• Broad spectrum
• E.g. ceftriaxon...
Carbapenems
• Broad spectrum
• β-lactam ring largely resistant to β-lactamases
• E.g. meropenem, ertapenem
Macrolides
• Bacteriostatic
• Macrolide ring activity
– Binds irreversibly to 50S subunit of bacterial
ribosome; inhibits ...
Aminoglycosides
• Bactericidal
• Bind irreversibly to 30S subunit of bacterial
ribosome
– Prevents elongation of polypepti...
Quinolones
• Bactericidal
• Bind to DNA gyrase-DNA complex
– Inhibits DNA replication
• E.g. ciprofloxacin
Sulphonomides
• Bacteriostatic
• Compete with substrate of enzyme
responsible for folic acid synthesis
• E.g. trimethoprim
Tetracyclines
• Bacteriostatic
• Prevent tRNA binding to 30S subunit
– Inhibits protein synthesis
• E.g. doxycycline
Others
• Metronidazole
(imidazole)
– Breakdown products
disrupt DNA helix; inhibits
nucleic acid synthesis
– Good for anae...
Antibiotics used…
• Infection by organ system
• Reference: BNF
• Highlighted in red = those we probably need
to have a gra...
GI
• Campylobacter enteritis
– Ciprofloxacin or erythromycin
• Salmonella
– Ciprofloxacin or cefotaxime
• Shigellosis
– Ci...
CVS
• Endocarditis initial ‘blind’ therapy
– Flucloxacillin (or benzylpenicillin if symptoms less severe) +
gentamicin
• E...
RS
• Haemophilus influenzae epiglottitis
– Cefotaxime or chloramphenicol IV
• Acute exacerbations of chronic bronchitis
– ...
CNS
• Meningitis initial empirical therapy
– Benzylpenicillin or cefotaxime
• Meningitis caused by meningococci
– Benzylpe...
Urinary
• Acute pyelonephritis
– A broad-spectrum cephalosporin or a quinolone
• Acute prostatitis
– Ciprofloxacin or oflo...
Genital
• Syphilis
– Benzathine benzylpenicillin (unlicensed) or doxycycline or
erythromycin
• Uncomplicated gonorrhoea
– ...
ENT
• Pericoronitis (infected wisdom tooth)
– Metronidazole or amoxicillin
• Acute necrotising ulcerative gingivitis
– Met...
Eye
• Purulent conjunctivitis
– Chloramphenicol or gentamicin eye drops
Skin
• Impetigo (superficial infection, Staph. aureus/Strep. pyogenes)
– Topical fusidic acid (or mupirocin if methicillin...
M/S
• Osteomyelitis
– Flucloxacillin or clindamycin if penicillin-allergic (or
vancomycin if resistant Staph. epidermidis ...
Antibiotic Resistance
How?
• Natural
selection/environmental
stresses (point mutations)
• Horizontal gene transfer
– Plasm...
Antibiotic Resistance
• Some examples:
– Meticillin-resistant Staphylococcus aureus (MRSA)
• Wounds; ulcers; IV lines; abs...
Eukaryotes
• Candida albicans
• Cryptosporidium parvum
• Entamoeba histolytica
• Giardia intestinalis
• Pneumocystis jirov...
Candida albicans
• Yeast  Candidiasis:
– Cutaneous, GU, GI, resp. tract, systemic…
• Opportunistic
• Disease relates prim...
Cryptosporidium parvum
• Protozoan  Cryptosporidiosis
– Parasitic disease of mammalian GIT
• Faeco-oral route of transmis...
Entamoeba histolytica
• Anaerobic protozoan
• Amoebic dysentery
– Bloody diarrhoea
– Painful passage of stool
– Colicy abd...
Pneumocystis jiroveci
• Yeast-like fungus
• Common cause of
pneumonia in AIDS
• Opportunistic
• Rx: co-trimoxazole +
proph...
Giardia intestinalis
• Flagellated protozoan  Giardiasis
• Common waterborne disease; soil, food.
• Faeco-oral route of t...
Trichomonas vaginalis
• Protozoan  Trichomoniasis
• STI
– Vagina/urethra women
• Frothy yellow-green discharge with stron...
Viruses
• EBV
• HAV
• HBV
• HCV
• HEV
• HIV
• HPV
• HSV
• VZV
• RSV
• Influenza
• Norovirus
• Rhinovirus
• Rotavirus
EBV
• Epstein Barr Virus = Human Herpes Virus 4
(HHV4)
• Cold symptoms  infectious mononucleosis
• Fatigue, fever, sore t...
Hepatitis – HAV/HBV/HBC/HEV
• See lecture!
HIV
• See lecture!
Human Papilloma Virus - HPV
• Low risk – genital warts (STI)/skin warts
• High risk: Ca cervix, vagina, vulva, anus, penis...
Herpes Simplex Virus - HSV
• = Human Herpes Virus (1 &2)
• Types:
– Orofacial herpes (most common), i.e. herpes labialis (...
Varicella Zoster Virus - VZV
• = Human Herpes Virus 3
• Fluid-filled blisters surrounded by reddened skin
• General malais...
Respiratory Syncitial Virus - RSV
• Common cause of bronchiolitis/viral pneumonia
in kids (< 6/12 mostly);
• Older childre...
Influenza
• Oseltamivir and
zanamivir as post-
exposure prophylaxis
– Inhibit neuraminidase
• Vaccines
– Seasonal
• High r...
Norovirus
• Winter vomiting bug; RNA virus
• Most common cause of gastroenteritis in UK
– D&V, fever, etc.
• Faeco-oral ro...
Rotavirus
• As for norovirus…
Rhinovirus
• Causes common cold; triggers acute asthma
exacerbations
• RNA virus
• Aerosol-droplet; contaminated surfaces
...
Notifiable diseases!
Anthrax Ophthalmia neonatorum
Cholera Paratyphoid fever
Diphtheria Plague
Dysentery (amoebic or bacil...
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Microbiology - bacteria, fungi, yeasts and viruses

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Microbiology - bacteria, fungi, yeasts and viruses

  1. 1. Microbiology Bacteria, Viruses and Yeast/Fungi …and some drugs and stuff Sarah Watson, 2010
  2. 2. Bacteria
  3. 3. Pathogenicity Factors 1. Adherence factors Allow adherence to body surfaces 2. Invasins Promote tissue invasion 3. Endotoxins/exotoxins Cause the damage! 4. Factors that confer ability to evade immune response = virulence factors = how bacteria cause disease
  4. 4. Which cause disease? 1. Classics E.g. Mycobacterium tuberculosis 2. Commensals E.g. Escherichia coli 3. Opportunists E.g. Pneumocystis jiroveci
  5. 5. Gram Staining Blue-black/violet Pink/red
  6. 6. Gram Positive Bacilli • Clostridium – botulinum – difficile – perfringens – tetani, etc. • Bacillus – anthracis (anthrax) – cereus • Listeria monocytogenes • Actinobacteria • Enterococcus • Lactobacillus • Mycobacterium Cocci • Staphylococcus aureus • Streptococcus – Group A: pyogenes – Group B: agalactiae – pneumoniae (diplococci); α-haemolytic β-haemolytic
  7. 7. Gram Positive Bacilli Clostridium difficile
  8. 8. Gram Positive Cocci Stapylococcus aureus Streptococcus pyogenes Streptococcus pneumoniae
  9. 9. Clostridium • Food poisoning (C. perfringens) • Diarrhoea (C. diff.) • Botulism (C. botulinum) • Tetanus (C. tetani) • Sepsis of unknown source Listeria monocytogenes • Gastroenteritis
  10. 10. Bacillus anthracis • Causes anthrax • 3 types: – Cutaneous • Localised inflammatory black necrotic lesion (eschar) • If leads to systemic infection, can be fatal – Pulmonary • Massive oedema and shock (pretty fatal) – Gastrointestinal • Anorexia, nausea, vomiting, abdo pain, haemorrhagic diarrhoea • Can be fatal
  11. 11. Staph. aureus (MSSA/MRSA) • Cellulitis • Venous leg ulcer • Infected cannulation site • HAP (MRSA) • Sepsis of unknown source
  12. 12. Strep. • Cellulitis • Necrotizing fasciitis • Venous leg ulcers • Acute otitis media (Strep. pneumoniae) • Pharyngitis (Strep. pyogenes) • CAP (Strep. pneumoniae) • Cystitis (Strep. agalactiae) Strep. pyogenes
  13. 13. Gram Negative Bacilli • Campylobacter jejuni • ‘Coliforms’ • Escherichia coli • Helicobacter pylori • Klebsiella spp. – pneumoniae • Legionella pneumophila • Proteus spp. • Pseudomonas aeruginosa • Salmonella spp. – typhi – enteriditis • Shigella spp. • Treponema pallidum • Enterobacter • Vibrio cholerae Cocci • Neisseria (diplococci) – gonorrhoeae – meningitidis Coccobacilli • Haemophilus influenzae Others • Gardnerella vaginalis (variable) • Mycobacterium tuberculosis (AAFB)
  14. 14. Gram Negative Bacilli E. coli H. pylori
  15. 15. Gram Negative Bacilli (contd.) Pseudomonas aeruginosa Salmonella typhi
  16. 16. Gram Negative Cocci Neisseria meningitidis
  17. 17. Gram Negative Coccobacilli Haemophilus influenzae
  18. 18. Mycobacterium tuberculosis
  19. 19. • Campylobacter jejuni/enteritis – Diarrhoea • ‘Coliforms’ (inc. ESBLs) – HAP – Cystitis – Pyelonephritis – Abdominal sepsis – Sepsis of unknown source • Escherichia coli – Cystitis – Pyelonephritis – Diarrhoea • Helicobacter pylori – Peptic ulcers – Ca stomach • Klebsiella pneumoniae – CAP/HAP • Legionella pneumophila – CAP • Proteus spp. – Cystitis – Pyelonephritis • Pseudomonas aeruginosa – HAP • Salmonella spp. – Typhi (typhoid) – Enteriditis (diarrhoea) • Shigella spp. – Diarrhoea • Treponema pallidum – Syphilis
  20. 20. • N. gonorrhoeae – Gonorrhoea – Vaginal discharge – Urethritis – PID • N. meningitidis – Meningitis – Sepsis of unknown source • Haemophilus infleunzae – Acute otitis media – Community acquired pneumonia (CAP) • Gardnerella vaginalis – Vaginal discharge – Bacterial vaginosis – Vaginitis • Mycobacterium tuberculosis – TB
  21. 21. Meningitis – common causative organisms • Neonates – Streptococcus pneumoniae (pneumococcal meningitis) – Escherichia coli – Listeria monocytogenes • Older infants/children – Streptococcus pneumoniae – Neisseria meningitidis (meningococcal meningitis) – Haemophilus influenzae • Adults – Streptococcus pneumoniae – Neisseria meningitidis • Older adults (>50) – Listeria monocytogenes • Pregnancy – Listeria monocytogenes • Vaccinations against the top 3 (Strep, Neiss & Haemoph) exist and have led to a decline in cases NB: 3 most common = NHS Neisseria, Haemophilus, Streptococcus
  22. 22. Gram Null • Chlamydia trachomatis • Chlamydophila pneumoniae (Chlamydia) Elementary body Reticulate body
  23. 23. Summary – Bacteria Types Gram +ve • Coccus – Staph and Strep • Bacillus – Clostridium – Listeria – (anthracis) Gram -ve • Coccus – Neisseria • Cocco-bacillus – Haemophilus Everything else we need to know is Gram –ve bacillus, except Mycobacterium tuberculosis & Gardnerella vaginalis (plus the couple of Gram null ones).
  24. 24. Antibiotics - types • Penicillins – Inc. co-amoxiclav • Cephalosporins – Cefotaxime – Ceftriaxone – Cefalexin • Macrolides – Clarithromycin – Erythromycin • Aminoglycosides – Gentamicin • Quinolones – Ciprofloxacin • Sulphonamides – Septrin (co-trimoxazole) – Trimethoprim • Tetracyclines – Doxycycline – Tetracycline • Others – Chloramphenicol – Metronidazole – Vancomycin
  25. 25. Penicillins • Bacteriocidal • β-lactam (ring) activity – Inhibits peptidoglycan cross-linking • Usually active against Gram +ve orgs (e.g. penicillin, flucloxacillin, amoxicillin; co-amoxiclav broader spectrum) • Penicillin G – IV (benzylpenicillin sodium) • Penicillin V – oral (phenoxymethylpenicillin) • Benzathine benzylpenicillin – IM (special order: syphilis)
  26. 26. Cephalosporins • Bacteriocidal • β-lactam activity • Less susceptible to penicillinases • Broad spectrum • E.g. ceftriaxone, cefotaxime (3rd generation)
  27. 27. Carbapenems • Broad spectrum • β-lactam ring largely resistant to β-lactamases • E.g. meropenem, ertapenem
  28. 28. Macrolides • Bacteriostatic • Macrolide ring activity – Binds irreversibly to 50S subunit of bacterial ribosome; inhibits protein synthesis • Used against Streptococci/MSSA in penicillin allergy • E.g. erythromycin
  29. 29. Aminoglycosides • Bactericidal • Bind irreversibly to 30S subunit of bacterial ribosome – Prevents elongation of polypeptide chain (tRNA) • Good for Gram –ve aerobes • E.g. gentamicin
  30. 30. Quinolones • Bactericidal • Bind to DNA gyrase-DNA complex – Inhibits DNA replication • E.g. ciprofloxacin
  31. 31. Sulphonomides • Bacteriostatic • Compete with substrate of enzyme responsible for folic acid synthesis • E.g. trimethoprim
  32. 32. Tetracyclines • Bacteriostatic • Prevent tRNA binding to 30S subunit – Inhibits protein synthesis • E.g. doxycycline
  33. 33. Others • Metronidazole (imidazole) – Breakdown products disrupt DNA helix; inhibits nucleic acid synthesis – Good for anaerobes • Chloramphenicol – Interferes with protein synthesis • Vancomycin (glycopeptide) – inhibits cell wall synthesis – Gram +ve orgs • Anti-tuberculous drugs – Initial phase (1st 2 months) • Rifampicin • Isoniazid • Pyrazinamide • Ethambutol – Continuation phase (next 4months) • Rifampicin • Isoniazid
  34. 34. Antibiotics used… • Infection by organ system • Reference: BNF • Highlighted in red = those we probably need to have a grasp of
  35. 35. GI • Campylobacter enteritis – Ciprofloxacin or erythromycin • Salmonella – Ciprofloxacin or cefotaxime • Shigellosis – Ciprofloxacin. Amoxicillin or trimethoprim can be used if organism sensitive. • Typhoid fever – Ciprofloxacin or cefotaxime • Clostridium difficile infection – Oral metronidazole or oral vancomycin • Biliary-tract infection – Ciprofloxacin or gentamicin or a cephalosporin • Peritonitis – A cephalosporin + metronidazole or gentamicin + metronidazole or gentamicin + clindamycin or piperacillin with tazobactam
  36. 36. CVS • Endocarditis initial ‘blind’ therapy – Flucloxacillin (or benzylpenicillin if symptoms less severe) + gentamicin • Endocarditis caused by staphylococci – Flucloxacillin • Endocarditis caused by streptococci (e.g. viridans streptococci) – Benzylpenicillin + gentamicin • Endocarditis caused by enterococci (e.g. Enterococcus faecalis) – Amoxicillin (or vancomycin if penicillin-allergic or penicillin- resistant) + gentamicin • Endocarditis caused by haemophilus, actinobacillus, cardiobacterium, eikenella, and kingella species (‘HACEK’ organisms) – Amoxicillin (or ceftriaxone if amoxicillin-resistant) + low-dose gentamicin
  37. 37. RS • Haemophilus influenzae epiglottitis – Cefotaxime or chloramphenicol IV • Acute exacerbations of chronic bronchitis – Amoxicillin (or tetracycline or clarithromycin; approx. 20% H. influenzae strains amoxicillin-resistant) • Low or moderate-severity community-acquired pneumonia – Amoxicillin (or doxycycline or clarithromycin) • High-severity community-acquired pneumonia of unknown aetiology – Co-amoxiclav + clarithromycin • Pneumonia possibly caused by atypical pathogens – Clarithromycin. • Hospital-acquired pneumonia – Early-onset infection (less than 5 days after admission to hospital), co- amoxiclav or cefuroxime – Late-onset infection (more than 5 days after admission to hospital), an antipseudomonal penicillin (e.g. piperacillin with tazobactam) or a broad-spectrum cephalosporin (e.g. ceftazidime) or another antipseudomonal beta-lactam or a quinolone (e.g. ciprofloxacin)
  38. 38. CNS • Meningitis initial empirical therapy – Benzylpenicillin or cefotaxime • Meningitis caused by meningococci – Benzylpenicillin or cefotaxime • Meningitis caused by pneumococci – Cefotaxime • Meningitis caused by Haemophilus influenzae – Cefotaxime • Meningitis caused by Listeria
  39. 39. Urinary • Acute pyelonephritis – A broad-spectrum cephalosporin or a quinolone • Acute prostatitis – Ciprofloxacin or ofloxacin or trimethoprim • ‘Lower’ urinary-tract infection – Trimethoprim or nitrofurantoin or amoxicillin or oral cephalosporin (e.g. cefalexin)
  40. 40. Genital • Syphilis – Benzathine benzylpenicillin (unlicensed) or doxycycline or erythromycin • Uncomplicated gonorrhoea – Ciprofloxacin. Pharyngeal infection requires ceftriaxone. • Uncomplicated genital chlamydial infection, non- gonococcal urethritis and non-specific genital infection – Azithromycin or doxycycline • Pelvic inflammatory disease – Doxycycline + metronidazole + i/m ceftriaxone or ofloxacin + metronidazole • Bacterial vaginosis – Oral or topical metronidazole or topical clindamycin
  41. 41. ENT • Pericoronitis (infected wisdom tooth) – Metronidazole or amoxicillin • Acute necrotising ulcerative gingivitis – Metronidazole or amoxicillin • Periapical or periodontal abscess – Amoxicillin or metronidazole • Periodontitis – Metronidazole or doxycycline • Throat infections – Phenoxymethylpenicillin (or clarithromycin if penicillin-allergic) • Sinusitis – Amoxicillin or doxycycline or clarithromycin • Otitis externa – Flucloxacillin or clarithromycin • Otitis media – Amoxicillin (or clarithromycin if penicillin-allergic)
  42. 42. Eye • Purulent conjunctivitis – Chloramphenicol or gentamicin eye drops
  43. 43. Skin • Impetigo (superficial infection, Staph. aureus/Strep. pyogenes) – Topical fusidic acid (or mupirocin if methicillin- resistant Staph. aureus) • Erysipelas (Strep. pyogenes commonly  inflamed dermis) – Phenoxymethylpenicillin (or clarithromycin if penicillin-allergic) • Cellulitis – Benzylpenicillin + flucloxacillin (or clarithromycin alone if penicillin allergic) • Animal and human bites – Co-amoxiclav
  44. 44. M/S • Osteomyelitis – Flucloxacillin or clindamycin if penicillin-allergic (or vancomycin if resistant Staph. epidermidis or metihcillin-resistant Staph. aureus) • Septic arthritis – Flucloxacillin or clindamycin if penicillin-allergic (or vancomycin if resistant Staph. epidermidis or methicillin-resistant Staph. aureus); cefotaxime if gonococcal arthritis or Gram-negative infection
  45. 45. Antibiotic Resistance How? • Natural selection/environmental stresses (point mutations) • Horizontal gene transfer – Plasmid transferred via conjugation pilus (~sex) Why? • Poor hand hygiene spreads resistant orgs • Poor compliance (sub- optimal concentrations) • Prescribed unnecessarily
  46. 46. Antibiotic Resistance • Some examples: – Meticillin-resistant Staphylococcus aureus (MRSA) • Wounds; ulcers; IV lines; abscesses…bacteraemia/septicaemia • Vancomycin/gentamicin • Trimethoprim/nitrofurantoin if UTI – Clostridium difficile • Diarrhoea…colitis…perforation/peritonitis • Vancomycin – Penicillin-resistant Streptococcus pneumoniae – Vancomycin-resistant enterococci – Multi-resistant salmonellae – Multi-resistant Mycobacterium tuberculosis • Streptomycin • Rx guided by sensitivity of infecting strain (BNF, 2009) (WHO)
  47. 47. Eukaryotes • Candida albicans • Cryptosporidium parvum • Entamoeba histolytica • Giardia intestinalis • Pneumocystis jiroveci • Trichomonas vaginalis
  48. 48. Candida albicans • Yeast  Candidiasis: – Cutaneous, GU, GI, resp. tract, systemic… • Opportunistic • Disease relates primarily to host immune state • Rx: – Topical e.g. clotrimazole – Oral e.g. fluconazole
  49. 49. Cryptosporidium parvum • Protozoan  Cryptosporidiosis – Parasitic disease of mammalian GIT • Faeco-oral route of transmission • Diarrhoea, abdo pain, etc. • No therapeutic agent clearly identified as effective – Supportive Rx – fluids – Paromomycin may relieve diarrhoeal symptoms – ? new treatments • Rx: self-limiting if immunocompetent
  50. 50. Entamoeba histolytica • Anaerobic protozoan • Amoebic dysentery – Bloody diarrhoea – Painful passage of stool – Colicy abdo pain • Amoebic abcesses of liver – Invades through GIT wall and spreads to other organs… • Rx: metronidazole/tinidazole
  51. 51. Pneumocystis jiroveci • Yeast-like fungus • Common cause of pneumonia in AIDS • Opportunistic • Rx: co-trimoxazole + prophylaxis
  52. 52. Giardia intestinalis • Flagellated protozoan  Giardiasis • Common waterborne disease; soil, food. • Faeco-oral route of transmission • Diarrhoea/abdo pain, etc. • Rx: metronidazole/tinidazole
  53. 53. Trichomonas vaginalis • Protozoan  Trichomoniasis • STI – Vagina/urethra women • Frothy yellow-green discharge with strong odour • Dyspareunia/dysuria • Inflammation; increased risk HIV infection – Urethra/sometimes prostate men • Discharge • Irritation inside penis/dysuria • Rx: metronidazole/tinidazole
  54. 54. Viruses • EBV • HAV • HBV • HCV • HEV • HIV • HPV • HSV • VZV • RSV • Influenza • Norovirus • Rhinovirus • Rotavirus
  55. 55. EBV • Epstein Barr Virus = Human Herpes Virus 4 (HHV4) • Cold symptoms  infectious mononucleosis • Fatigue, fever, sore throat, lymphadenopathy • Risk if rupturing spleen so no sports for 1/12! • Acetaminophen/NSAIDs to help fever/pain • Normally remains in WBCs for life • Ca risk if prolonged infection • ? vaccines
  56. 56. Hepatitis – HAV/HBV/HBC/HEV • See lecture!
  57. 57. HIV • See lecture!
  58. 58. Human Papilloma Virus - HPV • Low risk – genital warts (STI)/skin warts • High risk: Ca cervix, vagina, vulva, anus, penis • Respiratory papillomatosis • Untreatable; usually clears spontaneously – Can treat the warts • Vaccines: Cervarix, Gardasil
  59. 59. Herpes Simplex Virus - HSV • = Human Herpes Virus (1 &2) • Types: – Orofacial herpes (most common), i.e. herpes labialis (cold sores) – Genital herpes – Herpes whitlow (hands) – Ocular herpes (eyes) – Herpes encephalitis (brain)…+ others! • Watery blisters in skin/mucus membranes • Lies latent in nerve cell bodies; outbreaks • No cure per se – ? vaccines under development – Antivirals e.g. aciclovir cream – Analgesia – Anaesthesia (e.g. topical lignocaine)
  60. 60. Varicella Zoster Virus - VZV • = Human Herpes Virus 3 • Fluid-filled blisters surrounded by reddened skin • General malaise, sore throat, headache, etc. • Rx: – Topical antivirals e.g. aciclovir – Ig for at risk individuals (neonates, pregnant, etc) – Vaccine in seronegative/at risk individuals • Varilrix/Varivax – Pain management post shingles
  61. 61. Respiratory Syncitial Virus - RSV • Common cause of bronchiolitis/viral pneumonia in kids (< 6/12 mostly); • Older children/adults get a cold (limited to URT) • Rx: – Paracetamol/ibuprofen – Ribavirin • Inhibits range of DNA/RNA viruses – Palivizumab • Monoclonal Ab • Prevents serious LRTI in kids at risk
  62. 62. Influenza • Oseltamivir and zanamivir as post- exposure prophylaxis – Inhibit neuraminidase • Vaccines – Seasonal • High risk individuals – Pandemic • Pandemrix/Celvapan for swine ‘flu • See lecture notes
  63. 63. Norovirus • Winter vomiting bug; RNA virus • Most common cause of gastroenteritis in UK – D&V, fever, etc. • Faeco-oral route/contaminated food & water • Rx: – Stay at home – Paracetamol for fever symptoms – Rehydrate!
  64. 64. Rotavirus • As for norovirus…
  65. 65. Rhinovirus • Causes common cold; triggers acute asthma exacerbations • RNA virus • Aerosol-droplet; contaminated surfaces • No vaccine; supportive treatment only.
  66. 66. Notifiable diseases! Anthrax Ophthalmia neonatorum Cholera Paratyphoid fever Diphtheria Plague Dysentery (amoebic or bacillary) Poliomyelitis, acute Encephalitis, acute Rabies Food poisoning Relapsing fever Haemorrhagic fever (viral) Rubella Hepatitis, viral Scarlet fever Leprosy Smallpox Leptospirosis Tetanus Malaria Tuberculosis Measles Typhoid fever Meningitis Typhus Meningococcal septicaemia (without meningitis) Whooping cough Mumps Yellow fever + Consultant in Communicable Disease Control should be informed BNF 59

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