Question

How do reaserchers identify the spesific causes of infectious desease?

Answer 1

Examination under a microscope: Despite the development of rapid identification systems, direct microscopic examination of samples taken from the site of infection is often the most rapid method of identifying microorganisms that cause disease. Chemical stains are usually applied to make the microorganisms easier to see. The size and shape of the microorganisms and their stained color can help distinguish between different types. However, the microorganisms must be of sufficient size and number to be seen with a regular microscope. For example, viruses are too small to be seen with a regular microscope.

Culture: Usually, microorganisms are too few or too small to see, so they may be grown in the laboratory until there are enough to be recognized with chemical tests. The process of growing the organism is called a culture. Many microorganisms, such as the bacteria that cause gonorrhea or strep throat, can be grown this way.

Cultures can also be used to test the sensitivity of microorganisms to various antibiotics. This testing can help a doctor determine which drug to use in treating an infected person. This strategy is particularly important because microorganisms are constantly developing resistance to antibiotics that were previously effective.

Tests that detect antibodies: Some microorganisms, such as the bacteria that cause syphilis and the human immunodeficiency virus (HIV), are very difficult to culture. These infections, and many others, can be identified by finding antibodies to the microorganisms in the infected person's blood or body fluids (for example, cerebrospinal fluid).


Antibody-based tests are used to identify many infections, but they are not always reliable. These tests may not become positive for several days or weeks after people become ill. Also, these tests may indicate infection when none is present because they detect antibodies from a previous infection. Antibodies often stay in the body for many years after an infection has gone away.

Nucleic acid amplification tests: These tests, such as the polymerase chain reaction (PCR), identify pieces of the microorganism's genetic material (DNA), which are only present when the organism is present.
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Answer 2

Step 1: Isolate a sample of a pathogen to be identified from an infected individual.
Step 2: Test to see what infectious disease that it is.
Step 3: Inject a healthy individual with the suspected pathogen.
Step 4: Compare the symptoms to see if they are the same. If they are you can treat them. If not you need more tests.


This is my answer so change up #2 and #4

Answer 3

The following tests:
S-CRP - If around 30-150 most likely bacteria induced infection, if way higher, up to thousands, it's a viral infection.

If Bacterial infection.
Fecal culture - to determine which antibiotics are effective versus this bacteria. Perscribe Antibiotics which proved effective.

If Viral infection.
Investigate for further sympots such a Hepatite, HIV, Herpes, etc... All these have distinct symptoms which can be shown with specific bloodtests. (Not sure about herpes). If it's not a lifethreatning or dangerous virus, tell the patient to rest for a couple of days-up to two weeks.

If it's a dangerous virus perscribe medication accordingly, also might be a good idea to add supplement immunostimulants such as Cycloferon.

These are the most cost effective ways to indentify pathogen and treat it as far as i know.

Larne is absolutely correct about all the methods but most of the methods are not used that widely for all the patients due to the comparison in costs. a PCR costs vastly more than a C-CRP & Fecal culture for instance.