There are three main types of blood infections: viral, bacterial and fungal, according to WebMD. Some types of blood infections are meningitis, osteomyelitis, pneumonia, kidney infections, HIV/AIDS and sepsis. Two rarer types of blood infections are parasitic diseases and prion diseases, says the CDC.
One of the most serious infections is sepsis, according to WebMD. Sepsis occurs after an infection becomes established and the body's immune system causes widespread inflammation that cuts off blood and oxygen to vital organs. Only 50 percent of patients survive.
Another serious infection, meningitis, causes swelling in the lining of the brain and spinal cord. Viruses, bacteria or fungi can cause meningitis, according to Mayo Clinic.
Transmission of some blood infections occurs through sexual contact, states Mayo Clinic. One of the most serious of these is human immunodeficiency virus, or HIV, which attacks CD4 cells, a type of white blood cell that is a critical component of the body's immune system.
Most parasitic diseases are fairly rare, but there are a few exceptions, states the CDC. Malaria is one such exception. Infected mosquitoes transmit malaria, which causes severe, flu-like symptoms.
Prion diseases are another type of rare blood infections, according to the CDC. The most well-known prion diseases is Variant Creutzfeldt-Jakob Disease, also known as Mad Cow disease, which attacks the brain and eventually causes death.