Disease Pathogens

Viral Conjunctivitis

Pathogen: Adenovirus · Classification: Viral

Bacterial Conjunctivitis

Pathogen: Staphylococcus aureus, Streptococcus pneumoniae, or Haemophilus influenzae · Classification: Bacterial

Bacterial Conjunctivitis (Contact Lens Users)

Pathogen: Pseudomonas aeruginosa · Classification: Bacterial

Neonatal Conjunctivitis (Ophthalmia Neonatorum)

Pathogen: Neisseria gonorrhoeae, Chlamydia trachomatis, or Herpes Simplex Virus 2 (HSV-2) · Classification: Bacterial (N. gonorrhoeae, C. trachomatis) or Viral (HSV-2)

Trachoma

Pathogen: Chlamydia trachomatis · Classification: Bacterial

Keratitis (Viral)

Pathogen: Adenovirus, Herpes Simplex Virus (HSV), or Varicella-Zoster Virus (VZV) · Classification: Viral

Keratitis (Bacterial / Contact Lens Users)

Pathogen: Pseudomonas aeruginosa · Classification: Bacterial

Hordeolum (Stye)

Pathogen: Staphylococcus aureus · Classification: Bacterial

Blepharitis

Pathogen: Staphylococcus aureus · Classification: Bacterial

Dacryocystitis (Gram-Positive)

Pathogen: Staphylococcus aureus or Streptococcus pneumoniae · Classification: Bacterial

Dacryocystitis (Gram-Negative)

Pathogen: Haemophilus influenzae, Escherichia coli, or Pseudomonas aeruginosa · Classification: Bacterial

Preseptal (Periorbital) Cellulitis

Pathogen: Staphylococcus aureus or Group A Streptococcus spp. (S. pyogenes) · Classification: Bacterial

Orbital Cellulitis

Pathogen: Polymicrobial (Staphylococcus aureus [MRSA], Group A Streptococcus, and anaerobic bacteria) · Classification: Bacterial

Otitis Externa (Swimmer's Ear)

Pathogen: Pseudomonas aeruginosa or Proteus spp. · Classification: Bacterial

Malignant Otitis Externa

Pathogen: Pseudomonas aeruginosa · Classification: Bacterial

Acute Otitis Media (Bacterial)

Pathogen: Streptococcus pneumoniae, Haemophilus influenzae, or Moraxella catarrhalis · Classification: Bacterial

Acute Otitis Media (Viral)

Pathogen: Respiratory Syncytial Virus (RSV), Rhinoviruses, or Coronavirus · Classification: Viral

Mastoiditis

Pathogen: Streptococcus pneumoniae, Haemophilus influenzae, or Moraxella catarrhalis (bacterial complication of AOM) · Classification: Bacterial

Common Cold (Rhinosinusitis)

Pathogen: Rhinoviruses, Adenoviruses, Enteroviruses, or Coronaviruses · Classification: Viral

Sinusitis (Primary Viral)

Pathogen: Respiratory Viruses (most commonly Rhinovirus) · Classification: Viral

Sinusitis (Secondary Bacterial Superinfection)

Pathogen: Streptococcus pneumoniae, Haemophilus influenzae, or Moraxella catarrhalis · Classification: Bacterial

Viral Pharyngitis

Pathogen: Adenovirus, Parainfluenza, Influenza, Rhinovirus, or Epstein-Barr Virus (EBV) · Classification: Viral

GABHS Pharyngitis / Strep Throat

Pathogen: Group A Beta-Hemolytic Streptococcus pyogenes · Classification: Bacterial

Diphtheria

Pathogen: Corynebacterium diphtheriae · Classification: Bacterial

Infectious Mononucleosis

Pathogen: Epstein-Barr Virus (EBV) · Classification: Viral

Scarlet Fever

Pathogen: Streptococcus pyogenes (Group A Strep producing pyogenic exotoxins) · Classification: Bacterial

Peritonsillar Abscess

Pathogen: Polymicrobial (Group A Streptococcus [GABHS], Viridans Streptococci, Staphylococcus spp., +/- anaerobic bacteria) · Classification: Bacterial

Influenza

Pathogen: Influenza Virus (A, B, or C) · Classification: Viral

Whooping Cough (Pertussis)

Pathogen: Bordetella pertussis · Classification: Bacterial

Croup (Laryngotracheobronchitis)

Pathogen: Parainfluenza Virus (most common), Respiratory Syncytial Virus (RSV), or Influenza · Classification: Viral

Laryngitis

Pathogen: Parainfluenza Virus or Rhinovirus (most common) · Classification: Viral

Epiglottitis

Pathogen: Haemophilus influenzae Type B (HiB) · Classification: Bacterial

Bronchitis (Acute)

Pathogen: Respiratory Viruses (Influenza, Parainfluenza, RSV, Rhinovirus, Coronavirus) · Classification: Viral

Bronchiolitis

Pathogen: Respiratory Syncytial Virus (RSV) · Classification: Viral

Community-Acquired Pneumonia (Typical Bacterial)

Pathogen: Streptococcus pneumoniae (most common), Haemophilus influenzae, or Moraxella catarrhalis · Classification: Bacterial

Community-Acquired Pneumonia (Atypical Bacterial)

Pathogen: Mycoplasma pneumoniae, Legionella pneumophila, or Chlamydophila pneumoniae · Classification: Bacterial (lack standard peptidoglycan cell walls)

Nosocomial / Hospital-Acquired Pneumonia

Pathogen: Pseudomonas aeruginosa, Staphylococcus aureus, Acinetobacter spp., Escherichia coli, Proteus spp., or Klebsiella spp. · Classification: Bacterial

Aspiration Pneumonia

Pathogen: Klebsiella pneumoniae or Oral Anaerobes · Classification: Bacterial

Psittacosis

Pathogen: Chlamydophila psittaci · Classification: Bacterial

Pneumocystis Pneumonia (PCP)

Pathogen: Pneumocystis jirovecii · Classification: Fungal (atypical opportunistic fungus)

Pulmonary Histoplasmosis

Pathogen: Histoplasma capsulatum · Classification: Fungal (thermally dimorphic fungus)

Pulmonary Aspergillosis

Pathogen: Aspergillus fumigatus · Classification: Fungal (opportunistic mold)

Tuberculosis

Pathogen: Mycobacterium tuberculosis · Classification: Bacterial (acid-fast bacillus containing mycolic acid)

Mycobacterium Avium Complex (MAC) Infection

Pathogen: Mycobacterium avium or Mycobacterium intracellulare · Classification: Bacterial (acid-fast bacillus)

COVID-19 Pneumonia

Pathogen: Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) · Classification: Viral

Herpes Labialis / Gingivostomatitis

Pathogen: Herpes Simplex Virus 1 (HSV-1) or Herpes Simplex Virus 2 (HSV-2) · Classification: Viral

Thrush (Oral Candidiasis)

Pathogen: Candida albicans · Classification: Fungal (yeast/pseudohyphae)

Candida Esophagitis

Pathogen: Candida albicans · Classification: Fungal

HSV Esophagitis

Pathogen: Herpes Simplex Virus (HSV) · Classification: Viral

Vincent Angina (Trench Mouth / ANUG)

Pathogen: Polymicrobial oral anaerobes · Classification: Bacterial

Sialadenitis

Pathogen: Staphylococcus aureus · Classification: Bacterial

Helicobacter pylori Gastritis / Peptic Ulcer Disease

Pathogen: Helicobacter pylori · Classification: Bacterial

Viral Gastroenteritis

Pathogen: Rotavirus (infants) or Norovirus (all ages) · Classification: Viral

Bacillus cereus Food Poisoning

Pathogen: Bacillus cereus (spore-forming) · Classification: Bacterial

Staphylococcus aureus Food Poisoning

Pathogen: Staphylococcus aureus · Classification: Bacterial

Clostridium perfringens Food Poisoning

Pathogen: Clostridium perfringens (spore-forming) · Classification: Bacterial

Botulism / Clostridium botulinum Food Poisoning

Pathogen: Clostridium botulinum (spore-forming, anaerobic) · Classification: Bacterial

Campylobacter Gastroenteritis

Pathogen: Campylobacter jejuni · Classification: Bacterial

Cholera

Pathogen: Vibrio cholerae · Classification: Bacterial

Salmonellosis (Non-Typhoidal)

Pathogen: Salmonella enterica (such as Salmonella enteritidis) · Classification: Bacterial

Typhoid Fever

Pathogen: Salmonella typhi · Classification: Bacterial

Shigellosis (Bacillary Dysentery)

Pathogen: Shigella spp. · Classification: Bacterial

C. diff Colitis (Pseudomembranous Colitis)

Pathogen: Clostridioides difficile (spore-forming, anaerobic) · Classification: Bacterial

ETEC Gastroenteritis

Pathogen: Enterotoxigenic Escherichia coli · Classification: Bacterial

EPEC Gastroenteritis

Pathogen: Enteropathogenic Escherichia coli · Classification: Bacterial

EHEC Gastroenteritis (Hemorrhagic Colitis / HUS)

Pathogen: Enterohemorrhagic Escherichia coli (such as O157:H7) · Classification: Bacterial

EIEC Gastroenteritis

Pathogen: Enteroinvasive Escherichia coli · Classification: Bacterial

EAEC Gastroenteritis

Pathogen: Enteroaggregative Escherichia coli · Classification: Bacterial

Hepatitis A

Pathogen: Hepatitis A Virus (HAV) · Classification: Viral

Hepatitis B

Pathogen: Hepatitis B Virus (HBV) · Classification: Viral

Hepatitis C

Pathogen: Hepatitis C Virus (HCV) · Classification: Viral

Amebiasis (Amoebic Dysentery)

Pathogen: Entamoeba histolytica · Classification: Parasitic (Protozoan)

Giardiasis

Pathogen: Giardia lamblia · Classification: Parasitic (Protozoan)

Cryptosporidiosis

Pathogen: Cryptosporidium hominis · Classification: Parasitic (Protozoan)

Ascariasis

Pathogen: Ascaris lumbricoides · Classification: Parasitic (Helminth / Nematode / Roundworm)

Pinworm (Enterobiasis)

Pathogen: Enterobius vermicularis · Classification: Parasitic (Helminth / Nematode / Roundworm)

Hookworm Infection

Pathogen: Ancylostoma duodenale or Necator americanus · Classification: Parasitic (Helminth / Nematode / Roundworm)

Beef Tapeworm

Pathogen: Taenia saginata · Classification: Parasitic (Helminth / Cestode / Tapeworm)

Superficial Mycosis

Pathogen: Trichophyton · Classification: Fungal (mold)

Subcutaneous Mycosis

Pathogen: Sporothrix · Classification: Fungal (dimorphic fungus)

Systemic Mycosis (Dimorphic)

Pathogen: Coccidiodes, Histoplasma, or Cryptococcus · Classification: Fungal