How to Build a Bottle Fly Trap

Build a Fly Trap

Mini Secondary Project: Help Break the Fecal-Oral-Cycle

If you have been living in Cambodia for any time now, you are probably aware there are a lot of flies here. Flies are a significant contributor to the fecal-oral-cycle, which is the fancy term for how bacteria from feces gets into peoples bodies causing diarrhea and other illness. Basically, with regard to flies, it works like this.

1. People defecate out in the open
2. Flies land on the feces and pick up bacteria and viruses
3. Flies land on peoples food contaminating the food
4. People eat the contaminated food and get sick

Ideally if we stop people defecating in the open, we could make a tremendous improvement to the general health of people in Cambodia. However, breaking the fecal-oral-cycle at the fly level can also be a significant help. This is a low cost mini project that you can do to help break the fecal-oral-cycle in your community.

How to Build a Fly Trap out of a Common Water Bottle to Help Break the Fecal-Oral-Cycle

1. Cut the top off the bottle, just below the point the neck begins to taper
2. Cut the bottom off the bottle, making sure there is enough room to invert the
   top section of the bottle into the bottom
3. Flip the bottom piece over and insert top piece into it, creating a contained
   funnel
4. Use tape or staples to fasten the two pieces (if needed)
5. Make two holes towards the open side of the trap and tie the string through
   them
6. To set up, fill the trap with sugar water and hang from a branch or post and
   flies will enter through the funnel but will be unable to escape
7. To dispose of dead flies, fill with water, remove top section, and dump out
   contents

Put it to Use; a Personal Story

My host family sister Thome runs a small community store in front of our house, which is behind my health center. She sells snacks to all the kids, and other goods one might need last minute, much like a corner convenience store. She also cooks and serves breakfast, lunch, and dinner. We get a lot of patients and the neighborhood folks eating here. There is never a shortage of flies buzzing about, and they really bug me.

PCV Rich Durnan teaching SryThome to build a fly trap from a plastic bottle in her village food shop. © Richard Durnan http://www.richdurnanphoto.com

I did this fly trap building project with her as we spoke about the fecal-oral cycle and the role flies play in it. Now the shop has several of these traps hanging over the tables and food preparation area catching flies all day. We found putting a little Red Bull or one of the other super sweet energy drinks available here in the trap as bait works great.

Patients from the health center and folks from the neighborhood that stop in to the shop often comment on the traps filled with dead and dying flies. Thome enthusiastically explains what they are for, and how they work. Everyone agrees they are a good idea. I hope I will be seeing traps like these popping up all around my community.

Give it a TRY

Why not try this activity with someone or some restaurant in your community? This fly activity can be found as an activity in the CHE Curriculum WASH Toolkit along with other complete lessons on the fecal-oral-cycle and household sanitation. Each lesson contains activities like this fly trap one with background information, Khmer transliterated vocabulary and questions,  and step by step instructions for the lesson.

Download the CHE WASH Toolkit here and all the other CHE Curriculum Toolkits here.