Microbiology How to discover the causative agent of a new disease and its mode of transmission:

The standard epidemiologic triangle model of infectious disease causation, asserts that communicable diseases are the result of the contact between the agent, surroundings and the host with the vector. Transmission in particular happens if the agent leaves the host or reservoir via an exit portal and then it is moved (transmitted) in a particular form and enters a vulnerable host, infecting it through a suitable portal of entry. This cycle is also is widely regarded as the sequence of infection.

The locale where the infectious agent usually breeds and multiplies in number is its reservoir. The environment, animals and humans are some of the reservoirs. A contagious agent can be transmitted to a host either directly from a reservoir or through other intermediary sources. There are several different ways by which diseases spread from the natural reservoir to the host. Here is a common classification scheme:

Direct: Direct contact and droplet spread.

Indirect: Vector borne (biologic or mechanical), airborne and vehicle borne.

When a contagious agent is moved to a vulnerable host by direct contact, this is known as the direct mode of spread/transmission (CDC, 2012). By knowing the reservoir and mode of transmission I can find the causative agent once I have identified the components of the epidemiologic triangle in relation to the Pasadena Fever.

2.

Tissue typing:

In humans there are two sorts of critical exterior cell particles that greatly determine tissue rejection. These are the blood type determining carbohydrate particles together with the HLA antigens (protein molecules). The linked anti-A and anti-B antibodies that form the ABO blood groups are normally IgM antibodies formed in the first years of baby formed by responses to environmental substances. Tests are done on the recipient before a transplant to ensure that, one does not have resistance against the donor's blood type and HLA antigen molecules.

The initial step involves the physician ascertaining that the blood types of the donor and the recipient are compatible. The subsequent step, a cross match test is performed. This test establishes that the recipient doesn't have resistance against the HLA antigens of the donor (BiologicTX, 2013).

When a sibling gets a kidney with a complete match from the other then it has a 95% chance of being functional by the end of a year. While if a father or mother, child or a half matched sibling donates a kidney it has an 85% chance of being functional at the end of one year (Brigham & Women's Hospital Kidney Transplant Staff, n.d.).

3.

The inflammatory process:

A localized biologic reaction that results from its attempt to defend itself is known as inflammation. The main aim is to eliminate pathogens, irritants, damaged cells and the causative dangerous stimuli and in the end to bring about a remedial process. This recuperative biological process is the outcome of an irritation on any part of the body and is an indication that it is attempting to heal itself. An inflammation is not an infection but can be caused by one. The body's reaction to an inflammation can be a result of an infection originating from a virus, fungus or bacterium (Nordqvist, 2015).

Acute inflammation begins within a short time span after a tissue is damaged. The injury may be an immune system response or from a physical cause.

During acute inflammation the following developments or processes take place

Arterioles, minute branches of arteries leading to the capillaries, dilate/expand resulting in an increased flow of blood.

Capillaries become more porous or permeable enabling different fluids and including plasma and other blood proteins to move into the interstitial spaces (ones between the cells).

Granulocytes and other macrophages move out of the venules (minute branches of veins that connect the capillaries to the veins) and capillaries and into the interstitial spaces. Of the granulocytes, the neutrophils are the ones which specifically come out. Granulocytes are a kind of leukoyte (WBCs), which are composed of minute sacs filled with enzymes that break down microorganisms. Foreign materials are usually also ingested by macrophages another kind of leukocyte (Nordqvist, 2015).

The five cardinal signs of information are heat, pain, redness, swelling and loss of function. These signs are more significant or easily felt when the inflammation occurs close to the body surface. When the affected area is deep in the body, for example in internal organs only a few signs might be evident. This is because not all internal organs have sensory nerve endings close by. This explains the lack of pain as in the case of acute inflammation of the lung, pneumonia....

If the interior lining of the chest wall, parietal pleura, is pushed against by inflammation resulting from pneumonia, there is no pain (Nordqvist, 2015).
4.

Synthesis of Antibodies:

There are different types of white blood cells and antibodies are one of them. Antibodies are also known as B. lymphocytes or B cells and are formed in bone marrow stem cells. When there is an antigen in the body, specific B cells are activated and these develop into plasma cells. These cells then make antibodies which are unique to that particular initial antigen. These cells are key in a branch of the immune system known as humoral, whereby plasma cell make antibodies (Bailey, 2015).

The antibodies are Y-shaped. When a foreign molecule or antigen enters the body antibodies are produced against it. Lymphocytes act as a sensor recognizing the antigen as being alien and producing antibodies specific to it. In the tips of the Y shaped antibodies are two distinctive binding sites which lock onto the unique shape of the antigen; thus the popular lock and key analogy is used to explain this phenomenon. The pathogen is destroyed by the antibodies and then engulfed and broken down by macrophages (Microbiology online, 2015).

5.

T cells:

These are some of the most critical cells in the immune system response as they coordinate B-cells, other T-cell subsets and other natural immune responses. Their response is in two defined pathways which involve two distinct subtypes; T1 and T2 cells. Normally T1 cells target parasites and bacteria (intravascular pathogens) by activating infected macrophages. On the other hand T2 cells activate antibody synthesis in B-cells, these neutralize extracellular pathogens. Activation of the cell commences various pathways which can lead to B cell antibody synthesis, class switching of immunoglobulin and macrophage action either directly or via the discharge of soluble factors (Tcells, 2009).

6. Causes of cancer and its links to the immune system:

In developed countries cancer is among the top three causes of death. Medical developments in the cure of cardiovascular conditions and the increase in life expectancy is likely to leave cancer as one of the most prevalent fatal diseases. When a Progeny of a transformed cell grows continuously it causes cancer (Janeway, Travers & Walport, 2001).

Contact with a carcinogen, genetic makeup, age, diet and immune system among other factors have a role in prompting a cell to not become normal and letting it grow uncontrollably into a cancer (Kenny, 2014).

The primary cells in charge of recognition and destruction of tumor cells is the T cell. T cells do this by carrying out immunologic surveillance, then spread and destroy tumor cells by recognizing TAAs. Other cells of the immune system control the T cell response; humoral antibodies generated against tumor cells (cellular cytotoxicity that is antibody-dependent) are required by some cells to start the interaction that results in the death of tumor cells. Surprisingly it is the T. suppressor cells that stop the body's immune reaction to the tumors (Gabrilovich, 2013).

7. Phenomenon of the Hemolytic disease of the Newborn (HDN):

When a rhesus negative mother conceives with a rhesus positive father the baby will likely have HDN. When the baby is still in the uterus, trouble will begin when the baby's rhesus positive erythroblasts (RBCs) will move into rhesus negative mother. This normally happens during delivery when the placenta is separated. The baby's red blood cells are destroyed (hemolysis) and broken down by antibodies from the mother. This makes the newborn anemic. The risk in this is that anemia restricts the capacity of blood to transport oxygen to vital tissues and organs.

This causes the following outcomes

More red blood cells are made rapidly in the liver, spleen and bone marrow in the baby's body in response to the hemolysis. This results in bigger organs. The new RBCs, are often undeveloped and not likely to carry out the functions of developed RBCs.

The hemolysis of RBCs causes the formation of bilirubin. The babies cannot effectively excrete the bilirubin which accumulates in blood, tissues and other fluids of its body (URMC, 2015).

Before birth the care for Hemolytic disease of the newborn may include:

• Intra-uterine blood transfusion of RBCs into the baby's blood circulation. This can be done by injecting the fetal abdominal cavity via the vein of the umbilical cord

In cases when the fetus has complications yet it has developed mature lungs then early delivery can be induced to prevent aggravation of HDN (URMC, 2015).

8. Diabetes type 1 and Autoimmunity

Immunity disorders cause inactivity or over working of the immune system. Autoimmune diseases are the result…