by Sam Malone

When tissues in the body are affected by microorganisms due to a weakened immune system, the body is more susceptible to infections. Microorganisms that cause infectious diseases include bacteria, fungi, parasites, and viruses. Some organisms work against the body, reducing the systems immunity, while others cause diseases. Certain kinds of infection are contagious and can spread from person to person, while others are present in the environment, transmitted by insect bites or through food and water that are contaminated. Serious kinds of infections will require medical attention and help in strengthening the immune system. The signs and symptoms differ according to the kinds of infection, but usually a patient will have chills or a fever.

Different Types

There are four different types of pathogens that cause infections, namely, bacterial, fungal, parasitic and viral.

Bacterial: Bacteria are one-cell organisms that can cause varied diseases due to infection that may affect only one particular part of the body or spread through the whole body. Infections due to bacteria include bacterial meningitis, bacterial pneumonia, blood stream infections, food poisoning, gonorrhea, pelvic inflammatory disease, septic arthritis, sinusitis, skin and soft tissue infections, strep throat, syphilis, toxic shock syndrome, and urinary tract infections. Kinds of bacteria that cause infections include bacillus anthracis, chlamydia, clostridium, enterobacter, Escherichia coli, klebsiella, menigococus, mycobacterium tuberculosis, pneumococcus, proteus, pseudomonas, salmonella, groups A and B streptococcus, shigella, staphylococcus aureus, and treponema palladium.

Fungal: Fungi mostly cause skin diseases, while they could lead to the lung or nervous system infections if the fungal spores are inhaled. The distinction between bacterial and viral infections and fungal infections is that the latter develop slowly and get better gradually. Fungal infections that affect the skin are usually athlete's foot, fungal nail infections, jock itch, scalp ringworm, thrush, and vaginal yeast infections. When you inhale fungal spores, it could lead to infections of the lung and sinus, causing aspergillosis, blastomycosis, coccidiodomycoses, cryptococcosis, and mucormycosis. Fungal infections tend to affect people with weaker immune systems; the fungus pneumocystis jirovec usually affects people suffering from AIDS.

Parasitic: Parasites are organisms are those that usually feed off another living organism in order to get food and sustain their growth. Parasites could either be infectious worms or protozoans that are single-celled. Parasites are usually transmitted via insect bites or from animal and human excreta. Parasitic worms tend to attack the gastrointestinal tract, leading to diseases like ancylostomiasis, ascariasis, cysticerosis, elephantiasis, intestinal tapeworms, pinworms, and river blindness. Diseases caused by the single-celled protozoans include amoebic dysentery, babesiosis, cryptosporidiosis, intestinal giardiasis, malaria, and vaginal trichomoniasis.

Viral: The most common type of infectious disease that humans are susceptible to are viral. Viruses cause a host of diseases and are tinier than bacteria as well. The most frequent disease that constantly affects humans on a day-to-day basis is the common cold, caused due to a viral infection. The virus attacks the human body and weakens it, and there are various viral illnesses that can affect you at any point of your life, varying in severity. Viral infections that could affect you include AIDs, aseptic meningitis, chicken pox, dengue, fifth disease, genital herpes and warts, infectious mononucleosis, influenza, shingles, viral encephalitis, viral fever, viral gastroenteritis, viral hepatitis, and yellow fever.


Every infectious disease displays signs and symptoms specific to the illness. However, there are a few common symptoms that recur for all infectious diseases, including fatigue, fever, loss of appetite, and muscle pain. Make sure you see a doctor immediately if you have a fever that stays for more than a week or two, have difficulty breathing, get a swelling or a rash, experience bad headaches accompanied with fever or seizures, have a constant cough for more than a week, or get bitten by an animal.

Preventing Infections

It is very difficult to completely prevent infections from attacking your body, but you can take precautions to cut down the chances of contracting an infection. Body infections can arise from injuries or open wounds, skin contact with an infected person, inhaling germs that are airborne, mosquito or tick bites, eating and drinking food or water that is contaminated, and sexual contact.

Tips to Reduce Infections

  • Maintain good hygiene; this means making sure that you wash your hands before your meals, before and after cooking food, and after you use the restroom.
  • Don't share personal items such toothbrushes, combs, or razors.
  • Avoid drinking from the same glass or eating from the same plate as someone else, as germs can get transferred.
  • Make sure that you protect yourself by getting all the necessary vaccination shots that are required to strengthen your immune system.
  • While cooking, make sure that your kitchen is clean. Avoid leaving cooked food outside for long periods of time.
  • If you have symptoms of an infection, avoid going to work as you could spread the infection to your co-workers.
  • If you or your partner has previously contracted a sexually transmitted disease, use condoms during sex.



Principles and Practice of Infectious Diseases, Sixth Edition; Gerald L. Mandell, M.D., et al., Editors; 2004

Warning: The reader of this article should exercise all precautionary measures while following instructions on the home remedies from this article. Avoid using any of these products if you are allergic to it. The responsibility lies with the reader and not with the site or the writer.

Warning: The reader of this article should exercise all precautionary measures while following instructions on the home remedies from this article. Avoid using any of these products if you are allergic to it. The responsibility lies with the reader and not with the site or the writer.
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