STRUCTURE OF VIRUS
4 Structural Proteins
SPIKE: allows virus to attach to the host
Recognizes and binds to the receptor angiotensin converting enzyme receptor 2
S1→ binds to the host cell receptor
S2→ mediates the fusion of the viral and cellular membranes
ENVELOPE: crucial for assembly and release of the virus from the host cell
MEMBRANE: defines the shape of the viral envelope
NUCLEOCAPSID: bound to the virus’s single strand of RNA
Inhibits the host cells defense mechanisms
Viral Envelope: viruses fatty outer layer and when in contact with soap it will break down killin the virus
LIFE CYCLE OF VIRUS
Virus enters the cell via fusion of the viral envelope with the host cell membrane
Virus particle is uncoated and its genome enters the cells cytoplasm
Virus produces their new proteins and genomes in the cytoplasm of the host cell by attaching to the hosts ribosomes
The ribosomes will translate the viral RNA to make proteins that make RNA polymerase
RNA polymerase reads the positive strand of RNA from the virus to make a negative strand of RNA
RNA polymerase will use the negative strand of RNA to make another positive strand of RNA as well as smaller strands of positive RNA
These smaller strands will be read by the host cells ribosomes to make the structural components of the virus
The endoplasmic reticulum will transfer these components to the golgi apparatus where the proteins and the RNA strand form a new virus
These new viruses are released from the host cell through exocytosis and infects other cells
MODE OF INFECTION
Respiratory droplets
This allows the virus to travel into the naval cavity, oral cavity, or eyes
Surfaces
The virus lives on surfaces for a few hours or a few days
If the host touches a surface with the virus and then touches their face, the virus can then enter through the naval cavity, oral cavity, or eyes
What cells does it infects?
Cells in the lungs, nasal passages, and intestines
What specific receptors does the virus binds to?
The virus binds to angiotensin converting enzyme 2 (ACE2) and transmembrane protease serine 2 (TMPRSS)
ACE2
An enzyme that lowers blood pressure by catalyzing the hydrolysis of angiotensin converting enzyme 2 into angiotensin.
TMPRSS
Promotes growth, and metastasis of prostate cancer cells
SYMPTOMS
Fever or chills
Cough
Difficulty breathing/shortness of breath
Headaches
Congestion
Nausea
This virus infects people through the respiratory tract which causes an inflammatory reaction such as a fever, muscle aches, or shortness of breath
The virus infects people differently depending on if they have the antibodies or not. If a person has the antibodies, they are more likely to fight off the disease and show less symptoms.
R NAUGHT
The R naught for COVID-19 is approximately 6.6
The mathematical term that indicates how contagious or infectious a disease
WHO IS MORE SUSCEPTIBLE?
Those over 65
Those who live in nursing homes or long term care facilities
Those who have serious underlying medical conditions
A healthy body can heal itself by make new healthy cells, however there are factors that can cause some COVID-19 cases to be worse
People with chronic lung disease, or people who smoke or use vaping products, their immune system is impaired
The viral load: how much of the virus is in your body
This represents how much the virus is replicating
Some people may have a higher viral load than others
VACCINES
A vaccine works by training the immune system to recognize and kill pathogens.
Antigens from the pathogen is introduced to the body to trigger an immune response
The body then produces antibodies to help fight off the virus or bacteria
ANTIBODIES
An antibody test does not test for the virus, it tests to see if your immune system has responded to and fought off the virus.
ELISA Testing: common antibody test
This test determines if you have antibodies for the virus or bacteria.
This test is performed by gathering a blood sample. The blood sample will then be mixed with the antigen for the specific virus. If the blood contains the antibody for the antigen, they will bind together.
Antibodies are produced by white blood cells called B cells. When an antigen binds to a B cell more identical B cells are produced, creating more antibodies.
B cells can survive for many decades. The next time cells become infected with the same pathogen, the response is quicker and stronger. This is what gives people immunity to some diseases.
TREATMENTS
Most people will be able to recover at home
Convalescent Plasma: The antibody containing plasma from a recovered patients blood is given by transfusion to a patient with COVID-19. The donor has the antibodies in their blood that helped fight COVID-19.
There are other medications can be used to reduce fevers and aches.
Ibuprofen
Advil