Background: Hepatitis B is a contagious virus that affects the liver, infection can last from a few weeks to a serious lifelong illness. Two different types of infection exist for this disease, "acute" and "chronic." Acute Hepatitis B is a short term illness that occurs within 6 months of exposure, Chronic Hepatitis B is long term and happens when the virus remains in the body. The younger the child is, the greater their chance of developing a chronic infection and this risk goes down as the child gets older. Approximately 90% of infected infants will develop a chronic infection.[3]

Situation: Bob has just graduated from medical school. He went on to serve his community. Especially he is interested in treating children. One day he saw two children, child M and child N, and found child M is infected with Acute Hepatitis B while child N is infected with Chronic Hepatitis B. Next day he saw two other children, child O and child P. Child O was younger, but child P was older.

Question: Which child had short term illness, child M or child N?
Answer: child M

Situation: Bob has just graduated from medical school. He went on to serve his community. Especially he is interested in treating children. One day he saw two children, child M and child N, and found child M is infected with Acute Hepatitis B while child N is infected with Chronic Hepatitis B. Next day he saw two other children, child O and child P. Child O was younger, but child P was older.

Question: Which child had long term illness, child M or child N?
Answer: child N

Situation: Bob has just graduated from medical school. He went on to serve his community. Especially he is interested in treating children. One day he saw two children, child M and child N, and found child M is infected with Acute Hepatitis B while child N is infected with Chronic Hepatitis B. Next day he saw two other children, child O and child P. Child O was younger, but child P was older.

Question: Did child M had long term illness or short term illness?
Answer: short term illness

Situation: Bob has just graduated from medical school. He went on to serve his community. Especially he is interested in treating children. One day he saw two children, child M and child N, and found child M is infected with Acute Hepatitis B while child N is infected with Chronic Hepatitis B. Next day he saw two other children, child O and child P. Child O was younger, but child P was older.

Question: Did child N had long term illness or short term illness?
Answer: long term illness

Situation: Bob has just graduated from medical school. He went on to serve his community. Especially he is interested in treating children. One day he saw two children, child M and child N, and found child M is infected with Acute Hepatitis B while child N is infected with Chronic Hepatitis B. Next day he saw two other children, child O and child P. Child O was younger, but child P was older.

Question: Which child's illness occured within six months of  exposure to the virus, child M or child N?
Answer: child M

Situation: Bob has just graduated from medical school. He went on to serve his community. Especially he is interested in treating children. One day he saw two children, child M and child N, and found child M is infected with Acute Hepatitis B while child N is infected with Chronic Hepatitis B. Next day he saw two other children, child O and child P. Child O was younger, but child P was older.

Question: In which child the virus remained in the body, child M or child N?
Answer: child N

Situation: Bob has just graduated from medical school. He went on to serve his community. Especially he is interested in treating children. One day he saw two children, child M and child N, and found child M is infected with Acute Hepatitis B while child N is infected with Chronic Hepatitis B. Next day he saw two other children, child O and child P. Child O was younger, but child P was older.

Question: Did child M's illness occur within six months of exposure or the virus remained in his body?
Answer: within six months of exposure

Situation: Bob has just graduated from medical school. He went on to serve his community. Especially he is interested in treating children. One day he saw two children, child M and child N, and found child M is infected with Acute Hepatitis B while child N is infected with Chronic Hepatitis B. Next day he saw two other children, child O and child P. Child O was younger, but child P was older.

Question: Did child N's illness occur within six months of exposure or the virus remained in his body?
Answer: virus remained in his body

Situation: Bob has just graduated from medical school. He went on to serve his community. Especially he is interested in treating children. One day he saw two children, child M and child N, and found child M is infected with Acute Hepatitis B while child N is infected with Chronic Hepatitis B. Next day he saw two other children, child O and child P. Child O was younger, but child P was older.

Question: Which child had more chance of developing a chronic infection, child O or child P?
Answer: child O

Situation: Bob has just graduated from medical school. He went on to serve his community. Especially he is interested in treating children. One day he saw two children, child M and child N, and found child M is infected with Acute Hepatitis B while child N is infected with Chronic Hepatitis B. Next day he saw two other children, child O and child P. Child O was younger, but child P was older.

Question: Which child had less chance of developing a chronic infection, child O or child P?
Answer: child P