1. Which of the following illustrates the concept of herd immunity?

a. Previously infected people who recover and develop immunity may transfer their immunity to other members of the population.

b. Infected populations in an area may die out thus disabling the agent's propagation due to absence of new hosts.

c. All members of the population must get vaccinated or develop immunity against an agent so that nobody gets infected further.

d. Vaccinated individuals who are exposed in their workplaces may protect their family members at home from infection.

2. Barangay health workers are currently tasked to seek out and report individuals in their barangays who have cough, colds, fever and chills. What type of public health surveillance was described?

a. Syndromic passive

b. Syndromic active

c. Sentinel active

d. Sentinel passive

3. Match the epidemic curve with the given outbreak description. - The burger patties served in a birthday party was undercooked.

C A himya Number of cases Number of cases 10 2 3 A S 6 7 6 9 10 2 4 5 7 Day's 1 Days D B Number of cases Number of cases N 10 2 3 4 5 6 7 9 1 7 9 10 Day's 1 2 4 DaysC A himya Number of cases Number of cases 10 2 3 A S 6 7 6 9 10 2 4 5 7 Day's 1 Days D B Number of cases Number of cases N 10 2 3 4 5 6 7 9 1 7 9 10 Day's 1 2 4 Days