Isaac worked on the effects of vitamin E and L-theanine on longevity and fecundity in Yellow Fever mosquitoes (Aedes aegypti).
Longer-lived mosquitoes are more likely to carry disease, therefore shortening the lifespan of mosquitoes in the wild is desirable. Conversely, captive bred, sterile mosquitoes, which can be released to outcompete disease-carrying wild mosquitoes often die more quickly than well-adapted wild mosquitoes and so extending their lifespan is desirable. Zac found that vitamin E had a dose-dependent effect on the survivorship of Yellow Fever mosquitoes, extending the mosquito lifespan in most cases.
The laboratory techniques Zac developed during his honours project helped him gain a PhD scholarship, carrying out research into controlling Yellow Fever mosquitoes at Oxitec, a company based within Oxford University that uses cutting-edge technology to defeat disease vectors.