Zoos Try to Ward Off a Penguin Killer

http://www.nytimes.com/2013/10/08/science/earth/zoos-aim-to-ward-off-a-penguin-killer.html?ref=earth

This article describes how an avian form of malaria holds a present danger for many zoos that hold penguins in captivity, as the said virus can be fatal to penguin colonies. In order to combat this, zoos will take many measures to prevent any way for mosquitos to transmit the virus to their penguins. From water treatment, to refrigeration, to medicinal treatment, to quarantine, to natural antibodies found on some penguins, zookeepers have to be very diligent. In the wild, malaria would not be a threat as all penguins live in arid environments in which mosquitoes do not live, thus preventing the progression of the virus.

Question: How can we apply information learned from observations on animal-based diseases to viruses that affect humans? Is it ethical to allow animals to endure such infections in order to learn about and prevent similar infections from happening to humans?