Among the many lessons of the coronavirus pandemic is how close humans are to the rest of the animal kingdom. We get diseases from other animals, and then we use more animals to figure out how to stop the diseases. As research ramps up treatments and vaccines, animals are crucial to fighting the pandemic.

There are different animals at each end of the pandemic, of course. The new disease almost certainly began with a bat virus, scientists agree. That virus probably passed through another animal, perhaps pangolins, on its way to humans.

But the animals that scientists will depend on in the lab are mice, first of all, and then perhaps ferrets or hamsters or monkeys. Around the world, different laboratories are racing to breed stocks of mice genetically engineered for research and testing the susceptibility of other animals to infection with the virus that causes Covid-19.

There are, of course, many objections to animal testing, particularly when it comes to primates, but researchers are deeply concerned about the hazards to humans of treatments or vaccines that have not been tried on other animals first.