Fundamentals Of Vaccine Immunology Online Test

Immunizations are cost effective as they prevent diseases rather than treating them, which can be expensive. They also provide herd immunity, meaning that when a large portion of the population is immunized, it protects those who are unable to receive immunizations due to medical reasons. Lastly, immunizations help avoid serious and life-threatening diseases by strengthening the body's immune system. Therefore, all of the mentioned benefits are true.

Live attenuated vaccines contain weakened forms of the pathogen that can still replicate and stimulate an immune response. While these vaccines are safe for most individuals, they can cause disease in those with weakened immune systems, such as those who are immunocompromised. This is because their immune system may not be able to effectively control the replication of the weakened pathogen, leading to the development of disease symptoms. Therefore, live attenuated vaccines are contraindicated for individuals with compromised immune systems.

Polio, Hepatitis A, and Rabies require an inactivated vaccine. Inactivated vaccines are made from viruses or bacteria that have been killed or inactivated, so they cannot cause the disease they are intended to protect against. These vaccines stimulate the immune system to recognize and fight the pathogen without causing the actual disease. Inactivated vaccines are typically given as a series of injections and provide long-lasting immunity. They are particularly important for diseases like Polio, Hepatitis A, and Rabies, where the inactivated form of the virus or bacteria can still stimulate an immune response and protect against future infections.

IgA is paired with its correct characteristic of being found in tears, blood, and saliva and acting as a first line defense against foreign antigens. This immunoglobulin is secreted onto mucosal surfaces and helps to prevent the attachment of pathogens to these surfaces. It plays a crucial role in protecting the body from infections at the sites of entry, such as the respiratory and gastrointestinal tracts.

MMR, Varicella, and Rotavirus are live attenuated vaccines. Live attenuated vaccines contain weakened forms of the virus or bacteria that cause the disease. These vaccines are able to stimulate a strong immune response without causing the actual disease. They provide long-lasting immunity and often require fewer doses compared to other types of vaccines. MMR vaccine protects against measles, mumps, and rubella, Varicella vaccine protects against chickenpox, and Rotavirus vaccine protects against severe diarrhea in infants and young children.

The correct answer is "A and B only" because T cells have multiple functions, including providing intracellular immunity against viruses and killing pathogens via cell lysis. However, they do not present antigens to B cells for destruction, which is a function performed by antigen-presenting cells like dendritic cells.

mRNA vaccines are a suitable option for Covid-19 because they use a novel approach to trigger an immune response. They work by introducing a small piece of the virus's genetic material, called messenger RNA (mRNA), into the body. This mRNA provides instructions for cells to produce a harmless piece of the virus, which then triggers an immune response. mRNA vaccines are highly effective, safe, and can be developed and produced quickly, making them a valuable tool in combating Covid-19.

B cells have several functions in the immune system. They can differentiate into immunoglobulins, which are antibodies that help combat bacteria and viruses. B cells also provide immunity by defending against antigens that survive inside cells. However, the statement "Differentiate into memory cells and quickly attack known antigens" is incorrect. Memory cells are actually a type of B cell that is formed after an initial immune response and can quickly recognize and respond to known antigens upon re-exposure. Therefore, the correct answer is A and B only.

mRNA vaccines provide cellular instructions to cells to produce a protein that triggers an immune response. Unlike live attenuated or inactivated vaccines, which use weakened or killed pathogens, mRNA vaccines work by introducing a small piece of genetic material called messenger RNA (mRNA) into the cells. This mRNA contains instructions for the cells to produce a specific viral protein, which then stimulates the immune system to mount a response. By mimicking the natural infection process, mRNA vaccines can effectively train the immune system to recognize and fight off the targeted pathogen.

Inactivated vaccines and mRNA vaccines both require a two-dose regimen. The first dose is used to "prime" the immune system by introducing the inactive or mRNA components of the vaccine. This allows the immune system to recognize and respond to the specific antigens present in the vaccine. The second dose is then given to further strengthen and enhance the immune response, providing a more robust and long-lasting protection against the targeted disease.