Meeting the Practical Needs of Officers and Soldiers: Insect-Repellent Agent Reaches the Rainforests of Mêdog

Insect-Repellent Agent Reaches the Rainforests of Mêdog

■ Su Zhou

Researchers from the Academy of Military Medical Sciences under the Academy of Military Sciences collect experimental samples in the rainforest. Photo by Zeng Qingjia

Just as dawn was breaking, with the morning mist still hanging over the rainforest, a patrol unit from the Mêdog Border Defense Company of the Tibet Military District had already set out on its route.

With summer's arrival, the Mêdog rainforest is hot and humid, and land leeches have entered their active season. Officers and soldiers guarding the border are frequently harassed by them, their skin left covered in bite wounds.

On this patrol, the unit was joined by several researchers from the Academy of Military Medical Sciences under the Academy of Military Sciences. Carrying a newly developed leech repellent of their own design, they had traveled nearly 4,000 kilometers to this southwestern frontier to walk through the rainforest and traverse treacherous paths alongside the border defense officers and soldiers, testing the effectiveness of the agent in the field.

Several years ago, the research team learned of the practical needs of the company's officers and soldiers and resolved to develop a safe and effective insect-repellent agent. Over the years, the team repeatedly screened and refined formulations from among hundreds of natural plant compounds, conducted multiple rounds of laboratory trials and small-scale field tests, and ultimately overcame a series of technical challenges to produce the new leech repellent.

Moving through the dense, vine-tangled rainforest, the constant buzzing of insects filled the air. The researchers kept close to the unit, carefully observing the environment while diligently recording data.

To better confirm the protective efficacy of the new leech repellent, the researchers deliberately refrained from applying the agent themselves, conducting a controlled comparison against the patrol officers and soldiers who had used it. Over the course of a patrol lasting several hours, multiple land leeches were found crawling on and biting the researchers, while virtually none attached to the officers and soldiers on patrol — fully validating the effectiveness of the new agent.

"In the past, after coming back from patrol, you could always find a dozen or so land leeches on your body," said He Yingxin, the officer leading the patrol. "Now that we have this agent, everyone feels much more at ease and can carry out their border-guarding duties with undivided attention (心无旁骛)."

In the next phase, the research team will draw on the firsthand data gathered during this field test to make targeted improvements to the agent's formulation, further extending its duration of protection, and safeguarding the health and safety of officers and soldiers on border duty.