Bacteria, Fungi and Viruses, Sizes and Significance (Sizes in Micrometers - MM)

Note: Most are above 0.1M in size. None are below 0.01 in size.

Organism Microbial Group Rod Length µm Rod or Coccus Diameter µm Source Significance
Absidia corymbifera Fungi   3.8 Environmental Zygomycosis
Acetobacter Melanogenus Bacteria 1.0-2.0 0.4-0.8   Strong beer/vinegar bacterium.
Acinetobacter Bacteria   1.3 Environmental Opportunistic infections
Acremonium spp. Fungi   2.5 Environmental Extrinsic Allergic Aveons
Actinomyces israelii Bacteria   1.0 Humans Antinomycosis
Adenovirus Virus   0.08 Humans Colds
Alcaligenes Viscolactis Bacteria 0.8-2.6 0.6-1.0   Causes ropiness in milk.
Alkaligenes Bacteria   0.75 Humans Opportunistic infections
Alternaria alternata Fungi   14.4 Environmental Mycotoxicosis
Arenavirus Virus   0.18 Rodents Hemorrhagic fever
Aspergillis spp. Fungi   3.5 Environmental Aspergillosis, Volatile Organic Compound
Aureobasidium pullulans Fungi   5 Environmental Chromomycosis
Bacillus anthracis Bacteria 3.0-10.0 1.0-1.3(1.1 average) Environmental Causes anthrax in mammals
Bacillus Stearothermophilus Bacteria 2.0-5.0 0.6-1.0   Biological indicator for steam sterilization
Bacillus subtilis Bacteria 2.0-3.0 0.7-0.8   Biological indicator for ethylene oxide sterilization
Blastomyces dermatiitidis Fungi   14 Environmental Blastomycosis
Bordetella pertussis Bacteria   0.25 Humans Whooping cough
Botrytis cinera Fungi   7 Environmental Extrinsic Allergic Aveons
Cardiobacterium   Bacteria 0.63 Humans Opportunistic infections
Chaetomium globosum Fungi   5.5 Environmental Chromomycosis, Volatile Organic Compound
Chiamydia psittaci Bacteria   0.3 Birds Psittacosis
Chlamydia pneumoiae Virus   0.3 Humans Pneumonia
Cladosporium spp. Fungi   9 Environmental Chromblastomycosis
Clostridium botulinum Bacteria 3.0-8.0 0.5-0.8   Produces exotin causes botulism
Clostridium Perinngens Bacteria 4.0-8.0 1.0-1.5   Produces toxin causing food poisoning
Clostridium tetani Bacteria 4.0-8.0 0.4-0.6   Produces exotoxin causing tetanus
Coccidioides immitis Fungi   4 Environmental Coccidiodomycosis
Coronavirus Virus   0.11 Humans Colds
Corynebacteria diphtheria Bacteria   1.0 Humans Diphtheria
Coxiella burnetii Bacteria   0.5 Cattle, sheep Q fever
Coxsackievirus Virus   0.027 Humans Colds
Cryptococcus neoformans Fungi   5.5 Environmental Cryptococcosis
Diplococcus Pneumoniae Bacteria   0.5-1.25   Causes lobar pneumonia
Echovirus Virus   0.028 Humans Colds
Emericella nidulans Fungi   3.3 Environmental Mycotoxicosis, Volatile Organic Compound
Epicoccum nigrum Fungi   20 Environmental Extrinsic Allergic Aveons
Erwina aroideae Bacteria   2.0-3.0 0.5 Causes soft rot in vegetables.
Escherichia coll Bacteria 1.0-3.0 0.5   Indicator of fecal contamination in water
Eurotium spp. Fungi   5.8 Environmental Extrinsic Allergic Aveons
Exophiala jeanselmei Fungi   2 Environmental Chromomycosis
Francisella tularensis Bacteria   0.2 Wild animals Tularemia
Geomyces pannorum Fungi   3 Environmental Extrinsic Allergic Aveons
Haemophilus influenzae Bacteria 0.5-2.0 0.2-0.3   Causes influenza and acute respiratory infections
Haemophilus influenzae Bacteria   0.43 Humans Meningitis, pneumonia
Haemophilus parainfluenzae Bacteria   1 Humans Opportunistic infections
Hantavirus Virus   0.07 Rodents Hantavirus
Helminthosporium Fungi   12.5 Environmental Extrinsic Allergic Aveons
Histoplasma capsulatum Fungi   3 Environmental Histoplasmosis
Influenza Virus 5 0.4-0.5 Humans, birds Flu
Klebsielia pneumoniae Bacteria 5     Opportunistic infections, causes pneumonia and other respiratory inflammation
Lactobacillus Delbrueckil Bacteria 2.0-9.0 0.5-0.8   Causes souring of grain-mashes
Legionella pneumophia Bacteria   0.6 Environmental Pontiac fever
Micromonospora faeni Actinomycetes   1 Agricultural Farmers' lung, Hypersensitivity Pneumonitis
Moraxella catarrhalis Bacteria   1.3 Humans Opportunistic infections
Moraxella lacunata Bacteria   1 Humans Opportunistic infections
Morbillvirus Virus   0.12 Humans Measles (rubeola)
Mucor plumbeus Fungi   7.5 Environmental Mucormycosis
Mycobacterium avium Bacteria   1.2 Environmental Cavitary pulmonary disorder
Mycobacterium intracellulare Bacteria   1.2 Unknown Cavitary pulmonary disorder
Mycobacterium kansasli Bacteria   .86 Humans Cavitary pulmonary disorder
Mycobacterium Tuberculosis Bacteria 1.0-4.0 0.2-0.5(0.86 average) Humans Hard swelling of body tissues. TB
Mycoplasma pneumoniae Bacteria   0.25 Humans Pneumonia
Mycoplasma pneumoniae (PPLO) Bacteria   0.3-0.5   Smallest known free-living organism
Neisseria meningitidis Bacteria   0.8 Humans Meningitis
Nocardia Brasilensis Actinomycetes   1.1 Environmental Nocardiosis
Paecilomyces variotii Fungi   3 Environmental Mucormycosis
Paracoccidioides brasilensis Fungi   2.3 Environmental Paracoccidioidomycosis
Parainfluenza Virus   0.22 Humans Flu
Paramyxovirus Virus   0.23 Humans Mumps
Parvovirus B19 Virus   0.022 Humans Filth disease,anemia
Pediococcus acidilactci Bacteria   0.6-1.0   Causes mash spoilage in brewing
Pediococcus Cerevisiae Bacteria   1.0-1.3   Causes deterioration in beer
Penicillium spp. Fungi   3.3 Environmental Mycotoxicosis, Volatile Organic Compound
Phialophora spp. Fungi   1.5 Environmental Chromomycosis
Phoma spp Fungi   3.3 Environmental Mucormycosis
Pneumocystis carinii Bacteria   2 Environmental Pneumocystosis
Poxvirus - Vaccinia Virus   0.23 Agricultural Cowpox
Pseudomonas aeruginosa Bacteria   0.57 Environmental Opportunistic infections
Pseudomonas mallei Bacteria   0.77 Environmental Opportunistic infections
Pseudomonas pseudomallei Bacteria   0.57 Environmental Opportunistic infections
Pseudormonas diminuta Bacteria   1.0 0.3   Test organism for retention 0.2 µm membranes
Rhinorvirus Virus   0.023 Humans Colds
Rhizopus stolonifer Fungi   .8 Environmental Zygomycosis
Rhodoturula spp. Fungi   1.4 Environmental Extrinsic Allergic Aveons
Salmonella enteritidis Bacteria 2.0-3.0 0.6-0.7   Causes food poisoning
Salmonella hirschefeldii Bacteria 1.0-2.5 0.3-0.5   Causes enteric fever
Salmonella typhimurium Bacteria   1.0-1.5 0.5   Causes food poisoning in man
Salmonella typhosa Bacteria 2.0-3.0 0.6-0.7   Causes typhoid fever
Sarcina maxima Bacteria   4.0-4.5   Isolated from fermenting malt mash
Scopulariopsis spp. Fungi   6 Environmental Onychomycosis
Serratia marcescens Bacteria 0.5-1.0 0.5   Test organism for retention of 0.45 µm membranes
Serratia marcescens Bacteria   1.3 Environmental Opportunistic infections
Shigella dysenteriae Bacteria 1.0-3.0 0.4-0.6   Causes dysentery in man
Sporothrix schenckii Fungi   6.5 Environmental Sporotrichosis
Stachybotrys spp. Fungi   5.7 Environmental Stachybotryotoxicosis
Staphylococcus Aureus Bacteria   0.8-1.0 Humans Causes pus forming infections, opportunistic infections
Streptoccous lactis Bacteria   0.5-1.0   Contaminant in milk
Streptococcus pneumoniae Bacteria   0.9 Humans Pneumonia, otitis media
Streptococcus pyogenes Bacteria   0.6-1.0(0.9 average Humans Causes pus forming infections, scarlet fever, pharyngitis
Thermoactinomyces sacchari Actinomycetes   0.86 Agricultural Bagassosis
Thermoactinomyces vulgaris Actinomycetes   1 Agricultural Farmers' lung, Hypersensitivity Pneumonitis
Thermomonspora viridis Actinomycetes   0.6 Agricultural Farmers' lung, Hypersensitivity Pneumonitis
Togavirus Virus   0.063 Humans Rubella (german measles)
Trichoderma spp. Fungi   4.1 Environmental Mycotoxicosis, Volatile Organic Compound
Ulociadium spp. Fungi   15 Environmental Extrinsic Allergic Aveons
Varicella-zoster Virus   0.3 Humans Chickenpox
Wallemia sebi Fungi   3 Environmental Extrinsic Allergic Aveons
Yersinia pestis Virus   0.75 Humans Pheumonic plague