Dengue Patrol After Heavy Rain
After three days of heavy rain, the Grade 5 class does a 20-minute dengue patrol in the school yard. They have two pairs of gloves, one waste bag, and no larvicide. They find five places where water collects: (1) a broken coconut shell near the gate with about 1 cm of rainwater; (2) a 200-litre water barrel with a tight lid; (3) an old tyre used as a swing, holding water; (4) a flower vase in the office, whose water is changed every morning; (5) a blocked drain full of leaves and stagnant water. A younger student in Grade 2 has had a fever for two days and small red spots on his arms. His mother says it is only a cold and sends him to school. The class must decide which water containers to deal with first and what to tell the family.
1. Rank the three riskiest water containers and explain why each is risky. Explain why the other two are less urgent.
Read the worked answer
Ranking: 1) the old tyre, 2) the broken coconut shell, 3) the blocked drain.
Why the tyre is riskiest: It is outdoors, holds rainwater, and is not emptied. Dengue mosquitoes look for small collections of clean or partly clean stagnant water. A tyre can hold water for many days and is hard to notice because it is used as a swing.
Why the coconut shell is risky: It is small, but even a little water is enough for mosquito larvae. It is near the gate, so it is easy to miss and easy for many people to walk past.
Why the drain is risky: The water is stagnant and the leaves stop it flowing. It may be dirty, but it can still hold water long enough for mosquitoes. It also needs an adult because the drain may be blocked or unsafe to clear.
Why the other two are less urgent: The 200-litre barrel has a tight lid, so mosquitoes cannot get in. The office vase is changed every morning, so it is less likely to hold larvae for a full life cycle. The class should still check both, but they are not the first priority.
2. With only 20 minutes, two pairs of gloves and one waste bag, write an action plan in order. Say what to do and why.
Read the worked answer
Put on gloves and empty the tyre first. Tip the water onto dry ground away from the building, then store the tyre under cover or make a small hole so it cannot hold water again. This removes the biggest container quickly.
Pick up the coconut shell and put it in the waste bag. Empty it first. This is fast and removes a small but real breeding place.
Clear the drain with an adult's help. Remove leaves and rubbish so water can flow. Do not push the blockage further in. If the drain cannot be cleared in the time, report it to the caretaker and mark it as a job for adults.
Check the barrel lid and the office vase. Make sure the lid is tight. Ask the office staff to keep changing the vase water daily and to scrub the inside of the vase, because larvae can stick to the sides.
Finish with handwashing. Remove gloves, wash hands with soap, and put the waste bag in a covered bin.
Reasoning: The plan starts with the container that can breed the most mosquitoes and is easy to empty, then moves to smaller and harder jobs. The drain is left for an adult if it is unsafe.
3. What advice should the class give the Grade 2 student's family? Give two specific health actions.
Read the worked answer
Advice: A fever lasting two days with small red spots should be checked by a doctor or at the nearest clinic. It may be dengue or another illness; the mother cannot decide from the spots alone that it is only a cold.
Two specific actions:
- Take the child for a medical check today. Tell the health worker the fever has lasted two days and show the red spots. Early checking is important because dengue can become serious quickly.
- Do not give medicines without medical advice, especially aspirin. Give plenty of fluids and keep the child away from mosquito bites using a net or covered clothing while waiting for the clinic.
School action: The class should tell the teacher so the school can inform the family and check for more standing water near the child's home area if possible. The class should not say 'it is definitely dengue', but it should not ignore the warning signs either.