The Collectivist Fallacy that some monkey primates must die painful deaths so that other (human) primates might live free from disease because all primates form one big 'moral community' simply doesn't wash.
Yes monkeys are close to humans biologically but we still treat them - morally - as equal to the rocks we grind up without remorse to make concrete.
As instruments created merely to serve us human primates.
A Christian notion --- but spouted mostly by atheists ( for it is a fact the vast percentage of experimental scientists today are not just indifferent to religion but avidly atheist !).
Young grandson soldiers sacrifice themselves to save their granddads just as those granddads when young would do the same to save others. To that extent we humans do form one big moral community.
But no humans are ever killed in experiments to find a cure for monkey diseases - and if killing monkeys does result in finding a cure for a disease that afflicts both us and monkeys we do not then give that cure to sick monkeys - only sick humans.
Wartime allows medical experimenters greater opportunities to drop the monkey primate research and try their experiments on human primates instead and a lot of doctors and scientists can't get started quick enough - and not just in Axis Japan and Germany either ...