I had a thought about the use of neem leaves as an early treatment for chicken pox . Neem can also be used as a repellent for biting insects . There are several brands of Neem oil on the market that are sold as an ' all natural ' treatment for bed bugs . I wonder if the use of neem for chicken pox had something to do with people in the past not being able to completely differentiate the symptoms of a bed bug infestation from chicken pox . I suppose it ' s possible that at some point people noticed that their itchy bumps subsided after putting out neem leaves . Maybe they took this to mean that it cured their chicken pox when in fact it had scared away the bugs that had been biting them . I suppose it would be close to impossible to prove that this is the case , but it seems plausible .