The odor of clove essential oil was found to repel the human body louse Pediculus humanus corporis in a nonclinical, experimental study (February 2016). When placed in a petri dish with 50 microliters of clove oil concentrated in one spot, the lice avoided the spot with the clove oil.
They further found that two components of clove oil, eugenol and beta-caryophyllene, acted synergistically to repel the lice. The repellency of eugenol and beta-caryophyllene was much greater when the chemicals were used together instead of separately. Knowing that lice dislike the smell of clove somehow makes one love Clove essential oil more.