Question

Explain in detail how the following microbes transmit to humans, escape from our immunity and causing disease. And suggest and explain the rationale on ONE of its therapeutic methods.
SARS-CoV-2 (Virus for COVID-19)

1. Background of the microbes

-What is the structure?

-What is the unique feature?

2. Transmission route

- direct? indirect?

- when the microbe left human body, what is the survival rate?

- what is the basic reproductive member? (e.g. one people being infect, it can spread to two people)

3. Host-pathogen relationships

- The microbe uses what mechanism to escape the immune system (first line, second line, third line) enter body

- what is the method of microbe use and how it enter body (e.g. stick the mucosa...)?

4. Virulence factors and pathogenicity

- what is the virulence factors of this microbes?

- how much virulence factors that the microbes use to damage body?

- how to damage body (e.g. attack the cell and make you easily being sick, )?

-which molecule of body being break down and how it causes disease?

- when body being attack, which disease it will induce, induce which severe disease?

5. Treatment

- suggest one drug to treat Staphylococcus aureus

- introduce the drug

- target step

- how the drug does in body

- how it affects the bacteria

Answer 1

1.SARS CoV 2:

-single stranded RNA virus, which is enveloped

Positive single stranded

Belongs to family Coronaviridae

Has a helical nucleocapsid

Four structural protein- envelope, membrane, nucleocapsid, spike

- unique feature

2. Transmission route

-direct or indirect spread

It can be alive for about 4 to 72 hrs outside human body

R value is 1.2 to 2.01( reproduction number)

3.mechanism is translocation and fusion

During the SARS-CoV infection, S protein binds to the cellular receptor angiotensin-converting enzyme 2 (ACE2), this complex is then translocated to endosomes, where the S protein is cleaved by the endosomal acid proteases .to activate its fusion activity

-aerosol or droplet getting on the nasal or oral mucosa,

4.virulence factor: spike protein S

How much: one itself can cause

Increased positivity of the nucleocapsid also leads to disease

a virus‐mediated host immune response—a delayed but hyperactive innate immune response creating a cytokine storm, which lead to dampening of T"‐cell mediated antiviral functions.

novel coronavirus enters cells by binding to angiotensin-converting enzyme 2 (ACE2), a receptor on the cell surface.

ACE2 is abundantly expressed in the lungs and small intestine and is highly expressed in endothelial cells and smooth muscle cells of virtually all organs. Therefore, once in the circulatory system, SARS-CoV-2 is likely to spread via blood flow

It induces the ARDS acute respiratory distress syndrome, may be due to covid bronchopneumonia

5.- naficillin

- it belongs to cephalosporins

-it inhibits transpeptidase enzyme

- it is bactericidal ( kills the bacteria)

- bacteria is not able to build the cell wall, this leads to lysis of cell