Question

Chapter 12- Lymphatic System   

Case Scenario 5: Mr A had flu last winter but also got it again this time and admitted to hospital with the complaints of fever, sore throat, tenderness, pain and swollen lymph nodes on the neck region.

However, she received the vaccine for the same. The patient asks the doctor why that he is got the flue again despite the vaccine. The doctor says that this years’ flu is a new strain (type)

a. Explain how mild fever be beneficial to the body?   

b. What is the function of lymph nodes? Why do you think the lymph nodes swell during an active infection?

c. Is Mr. A showing the primary or a secondary immune response? Compare and contrast a primary and secondary immune response. Which is more rapid and why?

d. i) What type of immunity did Mr. A develop when he received the vaccine for flu?

ii) Do you think it was useful for Mr. A? How?

iii) What do you think is the benefit of receiving the vaccine?   

Answer 1

a) Mild fever is beneficial to the body in the time of active infections.

It is actually a defending mechanism by increasing the body temperature to fight against the microorganism as bacteria and virus cannot live longer in higher temperatures.

Also higher temperature of the body speeds up the functioning of cells including immune cells so that they can attack the pathogens more effectively.

b) Lymph nodes are immune system glands.
It helps to filter lymph and in order to identify the pathogens and help fight infections.
Lymph nodes contain B and T lymphocytes which are important components of immune system. B cell produce antibodies. Lymph node also filter cancer cells in the body.
Lymph nodes get swollen in response to illness, infection, stress or cancer. During an infection large number of reactive cells may enter the lymph node. Vascular engorgement and edema may occur due to cytokine release. These factors contribute to the lymph node swelling.

c) Mr. A is having a secondary immune response.
The primary immune response occurs when the antigen comes in contact with the immune system for the first time.
secondary immune response occurs when the person is exposed to the same antigen for second time( or 3rd,4th,..)

Secondary immune response stronger and faster than the primary immune response. This is due to the formation of memory cells when the immune system first encounter with antigen. This memory cells causes rapid secondary immune response.

d)

i)active immunity which is a type of adaptive immunity. Antibodies are produced in our body when it exposed to antigen. Flu vaccine contains inactivated strains of virus which acts as antigen within our body and causes the production of antibody

ii) It is useful in many ways. The antibody produced as a result of vaccine administration acts against subsequent exposure to antigens. So when a disease agent comed to our body, already synthesised antibody will destroy them. In case of flu vaccine, virus strains are constantly changing. So we have to take new vaccine every year.
iii) Vaccines acts by active immunity. If the vaccine contains inactive component of pathogen, it will act by active immunity. Antibody will be produced inside the body in response to the antigen.
The important benefit of taking vaccine is we can prevent the disease and reduce the complications of the disease to a certain extent.