Be a Scientist
• What do you know about disease?
• How do people get sick?
• Do other animals get sick too?
• How o scientists study diseases?
1. Make Observation
2. Ask Question
3. Form a Hypothesis
4. Test Your Hypothesis
5. Results Supported
6. Results Do Not Support
7. Conclusion, or Reform Question
Mosquito eggs in
Adult mosquito emerges from the water.
Where mosquitoes live and breed!
Swamps and standing water.
Mosquitoes will live anywhere where there is
Tree holes that hold water.
Old tires that collect rain water.
Anything that can collect water! Control mosquitoes by controlling trash!
Mosquitoes feed by absorbing blood from a host! Yuck!
Mosquitoes can carry and transfer Malaria,
Yellow Fever and Dengue Fever!
Mosquitoes can transfer these diseases to other
creatures while feeding on a host! (YUCK!)
Mosquitoes can spread the
virus by infecting a host, such
as a chipmunk.
As other Mosquitoes feed off of the
chipmunk, they become infected and
continue to spread the disease to
• How do you think scientists every made the
connection between Mosquitoes and these
Malaria in the blood! (Notice the cells
that are not round!)
• Discovery of the Malaria Parasite (1880)
• Charles Louis Alphonse Laveran, a French
army surgeon stationed in Constantine,
Algeria, was the first to notice parasites in the
blood of a patient suffering from malaria. This
occurred on the 6th of November 1880. For
his discovery, Laveran was awarded the Nobel
Prize in 1907.
• Discovery That Mosquitoes Transmit Malaria
• On August 20th, 1897, Ronald Ross, a British officer in
the Indian Medical Service, was the first to
demonstrate that malaria parasites could be
transmitted from infected patients to mosquitoes. In
further work with bird malaria, Ross showed that
mosquitoes could transmit malaria parasites from bird
to bird. This necessitated a cycle (the time interval
during which the parasite developed in the mosquito).
Thus, the problem of malaria transmission was solved.
For his discovery, Ross was awarded the Nobel Prize in
• On 20 August 1897, in Secunderabad, Ross made his landmark
discovery. While dissecting the stomach tissue of a mosquito
fed four days previously on a malarious patient, he found the
malaria parasite and went on to prove the role of Anopheles
mosquitoes in the transmission of malaria parasites in
• He continued his research into malaria in India, using a more
convenient experimental model, malaria in birds. By July
1898, he had demonstrated that mosquitoes could serve as
intermediate hosts for bird malaria. After feeding mosquitoes
on infected birds, he found that the malaria parasites could
develop in the mosquitoes and migrate to the insects' salivary
glands, allowing the mosquitoes to infect other birds during
subsequent blood meals.