Question 1: Define vaccination and explain its role in preventing infectious diseases.

Answer: Vaccination is the process of introducing a weakened or inactive form of a pathogen into the body to stimulate the immune system to produce protection against future infections.

Question 2: Describe how a vaccine helps the immune system to recognize and fight pathogens.

Answer: A vaccine introduces antigens from a pathogen to the immune system, prompting it to produce specific antibodies. This prepares the immune system to recognize and attack the actual pathogen if encountered later.

Question 3: What is herd immunity and why is it important in vaccination programs?

Answer: Herd immunity occurs when a high percentage of the population is vaccinated, reducing the spread of the disease and protecting those who cannot be vaccinated. It helps prevent outbreaks.

Question 4: Explain the difference between a live attenuated vaccine and an inactivated vaccine.

Answer: A live attenuated vaccine contains a weakened form of the pathogen that can replicate without causing disease, while an inactivated vaccine contains killed pathogens that cannot replicate.

Question 1: A vaccine requires a dose of 0.5 milliliters per person. How much vaccine is needed to immunize 150 people?

Answer: 0.5 ml x 150 = 75 ml

Question 2: If a vaccine has an efficacy rate of 95%, how many of 200 vaccinated individuals are expected to be protected?

Answer: 200 x 0.95 = 190 individuals

Question 1: Design a simple theoretical experiment to test the effectiveness of a new vaccine. Describe the variables you would control, the variables you would measure, and safety precautions you would recommend.

Answer: In the experiment, the independent variable is whether the subject receives the vaccine or a placebo. The dependent variable is whether the subject develops immunity or not. Controlled variables include age, health status, and exposure to the pathogen. Measure the rate of immunity after a set period. Safety precautions include ensuring informed consent, monitoring for adverse reactions, and proper handling of vaccines to avoid contamination.

Question 2: Identify three safety precautions that should be followed when administering vaccines in a community setting.

Answer: Ensure proper storage of vaccines, use sterile syringes to prevent infection, and obtain informed consent from recipients.

Question 1: In a trial of a new vaccine, 1000 people were vaccinated. Out of these, 50 contracted the disease within a year. Calculate the percentage of vaccinated individuals who were not protected, and interpret what this suggests about the vaccine's effectiveness.

Answer: 50 out of 1000 = 5%. This suggests that the vaccine was effective in protecting 95% of the vaccinated individuals, but a small percentage still contracted the disease.

Question 1: Discuss the impact of vaccination programs on controlling infectious diseases globally. Include at least two examples of diseases that have been significantly reduced or eradicated due to vaccination.

Answer: Vaccination programs have greatly reduced the spread of infectious diseases worldwide, leading to fewer cases and deaths. For example, smallpox has been eradicated globally, and measles cases have decreased dramatically in regions with high vaccination coverage, although outbreaks can still occur if coverage drops.

Question 2: Explain how the development of new vaccines can benefit public health, especially in controlling emerging diseases.

Answer: Developing new vaccines can provide protection against emerging diseases, reduce the spread of infections, and prevent pandemics. It also helps protect vulnerable populations and can improve global health security.