Infectious Diseases
And What Makes Them Different From One Another
Bacterial Infections
Bacteria are microscopic, unicellular organisms. Some bacteria are good for people but others carry disease. Those that carry disease, pathogens, enter the body through openings like through the respiratory system or mouth. They make a home in the body and then multiply rapidly, causing the person to be sick.
West Nile Virus carrying mosquito
Viral Infections
Viruses are parasitic pathogens that enter the body in ways similar to bacteria. However, viruses contain a limited supply of DNA. This leads them to enter their host's cells so they can use them to multiply. This process takes longer therefore viruses do not multiply as quickly as bacteria but are harder to get rid of.
Parasitical Infections
Parasites are pathogenic organisms that "feed" off their host. Sometimes the host shows little symptoms and does not seem to be affected and other times the parasite is fatal. There are two kinds of parasites; ectoparasites and endoparasites. Ectoparasites make their homes on the outside of the body (skin, hair). Endoparasites make their home inside the body (intestinal tract, bloodstream, internal organs; brain, eyes, liver, kidneys, etc.)
MRSA (superbug)
Methicillin-Resistant Staphylococcus Aureus, or MRSA is a version of the Staph Infection that has become resistant to antibiotics. As soon as one is infected they show symptoms starting with small red bump and increasing to pus filled abscesses. This is because people nowadays have become reliant on antibiotics for everything. The constant use of them creates a gap for natural selection to kick in. Most of the bacteria are killed by the antibiotic but the one or two that have a mutation that makes them resistant live. It becomes the start of a new generation of bacteria that cannot be harmed by antibiotics.