Types of Household Bacteria

A number of types of household bacteria exist within the home no matter how clean we think things are. Bacteria can live on any surface, including sinks and toilets, bathtubs and showers, in carpets and upholstery and even on our pets. Most types of bacteria are not harmful to our health, but it is still important to know what types of bacteria we are coming into contact with on a regular basis.

Staphylococcus spp.

• Staphylococcus spp. is a type of gram-positive bacteria that forms in clusters that resemble grapes and appear round under the microscope. There are 32 species of bacteria and eight sub-species of bacteria within the Staphylococcus genus. Most of these types of bacteria are completely harmless and capable of residing in the mucous membranes and on the skin of humans and animals. This type of bacteria is also found on household surfaces and in the microbial flora in soil.

Streptococcus spp.

• Streptococcus spp. is a type of bacteria that grows in pairs or chains, and is a gram-positive form of bacteria in the lactic acid group of bacteria. Like staphylococcus, this bacterium creates grape-like clusters. Although most types of streptococcus spp. do not cause illness, there are versions of these bacteria that can cause illness, including streptococcal pharyngitis, which is strep throat. Streptococcus can also cause bacterial pneumonia, erysipelas, endocarditis and necrotizing fasciitis.

Bacillus spp.

• This is a type of rod-shaped bacteria that falls into the firmicutes division. There are both pathogenic and free-living species of bacteria in this group. The cells can produce endospores in stressful environmental conditions that can remain dormant for an extended period of time. One type of bacillus spp. is especially dangerous: B. cereus can cause a food-borne illness that is similar in nature to staphylococcus.

Escherichia coli.

• Escherichia coli is also known as E. coli, and is a gram-negative type of bacteria that is typically harmless, but can also cause serious cases of food poisoning in certain situations. This is the bacteria that are commonly responsible for product recalls in certain foods. Escherichia coli is typically introduced through fecal contamination. There are harmless strains of Escherichia coli, which are part of the stomach's normal flora, while there are others that cause harm to the digestive system.