Vector-borne diseases are illnesses caused by microbes such as viruses, bacteria, and parasites that are transmitted by living organisms known as vectors. Mosquitoes and ticks are among the most common vectors and are responsible for spreading diseases such as malaria, dengue, Lyme disease, and West Nile virus.

Vectors become carriers when they pick up a disease-causing microbe from an infected animal or person and then pass it on through feeding or biting. These diseases are a growing global public health concern, with their distribution influenced by factors such as climate change, human behaviour, and global travel.

Prevention of vector-borne diseases focuses primarily on avoiding vector bites and reducing exposure to vector habitats through measures such as insect repellent, protective clothing, mosquito nets, and the removal of breeding sites. Although vectors can transmit disease, they also play important ecological roles, including supporting food webs, pollinating plants, and contributing to ecosystem balance.

This lesson will help students develop an understanding of how the environment, climate, and human health are interconnected, empowering them to explore the causes and prevention of vector-borne diseases in a changing world.