Experts’ assessment of the effectiveness of these remedies in the prevention and treatment of cholera, found all the remedies effective, but bitter leaf was the best option.
In the study, the researchers who investigated the ameliorative effects of Ogi-tutu (maize slurry), bitter leaf and guava leaf on mice infected with cholera found they were all able to prevent the growth of the germ that causes cholera, but to different extent.
They found that bitter leaf was the most effective in treating cholera. Next to it was guava leaf extract and Ogi-tutu was the least effective.
The raw extract of bitter leaf was obtained by crushing its leaves using sterile mortar and pestle. Decoction of the dried guava leaves were made by boiling it in water.
The roots and leaves of Bitter leaf, also known as ewuro in Yoruba land are used in traditional medicine to treat fever, hiccups, kidney disease and stomach discomfort, and as a worm expeller and antimalarial.
Psidum guajava, commonly known as guava is a plant used in the indigenous system of medicine for the treatment of various human ailments such as wounds, ulcers, bowels and cholera. The plant is also known for its antidiabetics, antidiarrheal and antidysentary properties.
Cholera is an acute diarrhoeal infection caused by ingestion of food or water contaminated with the germ, Vibrio cholera. Despite efforts to control cholera, the disease continues to occur as a major public health problem in many developing countries.
In Nigeria, since the first appearance of cholera epidemic in 1972, intermittent outbreaks have been occurring. However, several plants are used locally in the treatment of diarrhoea in South Western Nigeria. These include bitter leaf, guava leaf and Terminalia avicennoides (Bambara), Datura stramonium (gegemu in Yoruba land), garlic, Morinda Morindoides (ponju owiwi in Yoruba land) and Punica granatum (pomegranate).
But the researchers, in a 2016 study published in the African Health Science Journal, said bitter leaf was highly preventive and an effective treatment for diarrhoea, similar to castor oil induced diarrhoea.
The expert, noting that different parts of the guava tree posses many medicinal uses, declared that decoction of its leaves is capable of neutralising cholera.
These included Olufunke B Shittu; Olusola L Ajayi; Samuel O Bankole; and Temitope OS Popoola, all from the Federal University of Agriculture, Abeokuta.
Since, bitter leaf could be used for preventing and treatment of Vibrio cholerae infection, they declared that further investigations on the contents of bitter leaf as well as its mode of preventing and treating diarrhoea are warranted.
According to them, “This might channel a new pathway and better alternative therapeutic agents in the management of diarrhoea associated with V. Cholera.”
In 2010, researchers in the Journal of Infective disease had stated that extracts from leaf and bark of guava tree also have a strong antibacterial activity against multidrug-resistant cholera.
Results revealed that the V. Cholerae cells failed to grow in the presence of the effective dose of the guava active ingredient in the under laboratory conditions.
In fact, the growth of Vibrio cholera, the germ that causes cholera, in rice oral rehydration saline (ORS) was completely inhibited when 10 mg/mL of crude aqueous mixture was premixed with the ORS.
According to them, the wide availability of guava tree in countries like Bangladesh makes it a very promising alternative to commercial antibiotics that are losing efficacy in the treatment of cholera.
For millions who live in remote villages amid the constant risk of recurrent cholera and diarrhoea, the boiling of a few tender guava leaves, which are available in every household, together with rice powder, can be a live-saving solution for preventing cholera related death.