Intestinal infection from parasites has been recognized as a global health problem that can be particularly harmful to children aged 5 and younger, with a greater prevalence of infection in developing countries. A study published in Parasitology International suggests that oregano essential oil may act as a bioactive to reduce the infectivity of the protozoan parasite Cryptosporidium parvum.
Crypto infection is one of the leading causes of persistent diarrhea among children in low-resource settings. Crypto infection usually resolves without treatment in those who are immunocompetent, but can be life-threatening among immunodeficient individuals, such as children with malnutrition or patients with HIV.
Researchers at the University of Illinois looked at the use of oregano essential oil in fighting the infectivity of the Crytpo parasite. To test whether oregano essential oil could reduce Crypto infectivity, they used an in vitro model of human colon cells that had been infected with Crytpo. Once it infects cells, the parasite goes through an asexual cycle to keep replicating in numbers. In a living host, after a sexual cycle, the parasite (thick-walled oocysts) are ready to be shed into the feces and contaminate the next host. Importantly, oocysts are resistant to chlorine treatment, which presents a major hurdle for water purification efforts.
The researchers found that when they added oregano essential oil and/or carvacrol to the culture, the number of parasites being replicated was reduced. And a lesser number of parasites means lesser infectivity.
The researchers don’t yet fully understand whether the effect from the bioactive was on the organism (parasite) or the host. Further studies are focusing on how to encapsulate the oregano essential oil and sensory issues, as oregano essential oil has a strong odor and taste. Preliminary results of encapsulation tests show that even at the highest threshold of the needed dosage, the odor and taste could not be detected.