Rosemary, lemon oil, cinnamon, clove bud and eucalyptus. It sounds like the ingredients for an exotic meal, but this recipe is for your hands -- not your tummy. 

When mixed with water, those ingredients make a natural hand sanitizer, at least according to Dr. Lawrence Rosen, a New Jersey pediatrician who encourages his patients to use the concoction.

"I believe the data on these oils suggest it should be effective for flu viruses such swine flu," said Dr. Rosen. "Alcohol based sanitizers we have seen over time develop bacteria developed resistance to many of the things in them.  So the oils may be more effective."

The centuries old recipe is called "Thieves Oil,"  and dates back to the Middle Ages when grave robbers used the secret ointment to prevent catching the Bubonic Plague.

"Those oils today we understand through research have antibacterial properties," says Dr. Rosen.

Dr. Rosen writes about the sanitizer and why he prefers it to other anti-bacterial sanitizers like Purell on his blog wholechildcenter.org

At his office in Oradell, N.J., Dr. Rosen showed us how to make the sanitizer.  Start with a liquid container fill it 2/3 of the way with  water-add a tablespoon of aloe, and a few drops of  the following oils: lemon, cinnamon, eucalyptus and clove bud.

Then top off the bottle with water, shake it up and gently spray on the hands.

But not everyone's sold on the all-natural sanitizer.  Dr. Tanya Benenson, the medical director for NBC Universal, notes that hand washing is still the best solution for staying germ-free, but if you're on the go you should use something that's been tested and proven to fight bacteria.

"Before I would promote this globally or as an alternative I would want some more studies first," said Dr. Benenson.