Natural environment is filled with overwhelming numbers of microbes that may or may not be the cause of various types of infectious diseases. It is the immune system of human body that naturally resists infections. However, certain bacteria, fungi, parasites and viruses often find a way to attack the human body. The types of infections are described here according to microbes that cause them.
Infections caused by bacteria may localize to specific part of the body or may disseminate throughout its host. Various types of infectious diseases that are caused by Bacteria are bacterial meningitis, bacterial pneumonia, bloodstream infections, food poisoning, gonorrhea, pelvic inflammatory disease, septic arthritis, sinusitis, soft tissue and skin infections, syphilis, toxic shock syndrome, strep throat and urinary tract infections.
Escherichia coli, Clostridium, Bacillus anthracis, Chlamydia, Enterobacter, Klebsiella, Meningococcus, Mycobacterium tuberculosis, Pneumococcus, Proteus, Pseudomonas, Salmonella, Shigella, Staphylococcus aureus, Streptococcus group A & B and Treponemapallidum are bacterial species that are agents of various infections.
There are different types of fungi that cause various types of infectious diseases. Unlike bacterial and viral infections, fungal infections develop progressively and get healed gradually. Athlete’s foot, fungal nail infections, Jock itches, scalp ringworms, thrush, vaginal yeast infections, etc. are some of the surface fungal infections that are reported quite frequently by people.
On the other side, lung and sinus infections such as Aspergillosis, blast mycosis, Coccidioido mycosis, cryptococcosis and Mucor mycosis are caused due to inhalation of fungal spores. Immunity is quite considerable in case of contraction of fungal infections or resistance against it. People who have weak immune system may suffer from such infections and those with strong immune system may never contract. Pneumocystis pneumonia is common only among people who are affected by AIDS.
Organisms that thrive on other living beings are called Parasites. They infect other living organisms for food. Parasites range between unicellular protozoa to worms that may reach 20 feet in length. Babesiosis, Amoebic dysentery, intestinal cryptosporidiosis and giardiasis, Malaria and vaginal trichomoniasis are infections that are caused by Protozoan parasites while parasitic worms infect gastrointestinal tracts which cause illnesses such as Ancylostomiasis, Ascariasis, Cysticercosis, river blindness, etc. Intestinal tapeworms, pinworms, elephantiasis, etc. are commonly known to reside inside human or animals or both.
The most common of all types of infectious diseases are those caused by viruses. In fact, people suffer from viral illnesses several times throughout their life. Common cold is the most common example of viral illness that afflicts people multiple times through the span of their life. However, not all viral disorders are considered minor as common cold. AIDS, aseptic meningitis, chickenpox, dengue, fifth disease, genital herpes, infectious mononucleosis, measles, shingles, viral encephalitis, viral gastroenteritis, viral hepatitis, viral pneumonia and yellow fever are some diseases that also spread through viruses and are considered among the scariest.