Question 1: Measles is a highly contagious viral disease caused by the measles virus. It spreads through respiratory droplets when an infected person coughs or sneezes. The disease is characterized by symptoms such as a red rash, fever, and cough.

Answer: Measles is a contagious viral disease spread through respiratory droplets, causing symptoms like rash, fever, and cough.

Question 1: Define herd immunity and explain its importance in controlling Measles outbreaks.

Answer: Herd immunity occurs when a high percentage of the population is immune to a disease, reducing its spread and protecting those who cannot be vaccinated.

Question 2: Describe the mechanism by which the measles virus causes symptoms in the human body.

Answer: The measles virus infects respiratory cells, triggers an immune response, and causes inflammation and rash due to immune system activity.

Question 1: If a town has a population of 50,000 and 90% of the population is vaccinated against Measles, how many people are still susceptible to the disease? Show your calculation and answer in whole numbers.

Answer: 5000

Question 1: Identify three variables that should be controlled in an experiment testing the effectiveness of a measles vaccine.

Answer: Variables such as age, health status of participants, and exposure to other diseases should be controlled.

Question 2: List two safety precautions that must be taken when handling samples of the measles virus in a laboratory setting.

Answer: Wearing protective gloves and working in a biosafety cabinet are essential precautions.

Question 1: In a community where 85% of people are vaccinated against Measles, an outbreak occurs. The number of new cases over a week is 15. Explain what this data suggests about herd immunity in this community.

Answer: The data suggests that herd immunity may be insufficient to prevent outbreaks when vaccination coverage drops below the threshold needed for herd immunity, which is typically around 95% for Measles.

Question 1: Explain how the measles virus evades the immune system during infection and how vaccination provides protection. Include in your answer the concepts of immunity, virus mutation, and herd immunity.

Answer: The measles virus can evade the immune system by rapidly infecting cells and causing immune suppression. Vaccination introduces a harmless form of the virus or its components, stimulating the immune system to produce antibodies. This protects against future infections and helps establish herd immunity, which reduces the overall spread of the virus in the population. Variations in virus strains are minimal, so the vaccine remains effective.

Question 1: Discuss the importance of vaccination programs in preventing Measles outbreaks in developing countries. Include potential challenges faced in implementing these programs.

Answer: Vaccination programs are crucial in preventing Measles outbreaks by achieving herd immunity. Challenges include limited access to healthcare, vaccine storage issues, misinformation, and cultural resistance, which can hinder vaccination coverage.