Re-emerging infectious diseases such as Lassa fever, yellow fever, Ebola, measles, chicken pox, small pox, Dengue fever, viral hepatitis, Human Immuno-deficiency Virus (HIV), polio, cold and influenza virus, among others are posing fresh threat to human existence. Unfortunately, conventional medicines are failing: the pathogens have developed resistance to the drugs-of-choice. But researchers have in experimental models treated these deadly bugs with combination of local herbs and spices.
Nigerian researchers have identified and validated local plants for the treatment of viral infections.
Until now, several local herbs have been shown to have antibacterial and antiviral properties. Although there are no cures for viral infections, researchers suggest many natural remedies have been shown to provide relief and prevent complications.
The plants include: Bambusa vulgaris (bamboo) and Aframomum melegueta (alligator pepper), Azadirachta indica (neem), Allium cepa (onion), Allium sativum (garlic), rhizomes of Curcuma longa (turmeric), and Aloe vera, Vernonia amygdalina (bitter leaf), Garcinia kola (bitter kola), Citrus medica (lemon), Cymbopogon citratus (lemon grass), Moringa, Phyllanthus amarus, avocado (Persea americana), and Gardonema mushroom.
Researchers have also identified asthma herb (Euphorbia hirta), pawpaw (Carica papaya), bitter melon (Momordica charantia) and guava (Psidium guajava) extracts as potential 'cures' for viral infections.
Researchers from Ekiti State University, Ado Ekiti, and Kings University, Osun State have validated antiviral properties of two Nigerian plants- alligator pepper (grains of paradise) and bamboo.
The study was published in African Journal of Plant Science.
According to the researchers, ethanolic extracts were prepared from Bambusa vulgaris and Aframomum melegueta. They were analysed for antiviral activities against three human viruses namely: measles, yellow fever and polioviruses by standard laboratory tests.
The researchers wrote: "Both extracts showed antiviral activities against one or two viruses. B. vulgaris resulted in inhibition only on measles virus at Minimum Inhibition Concentration (MIC) of 62.5 µg/ml while A. melegueta inhibited measles and yellow fever viruses at MICs of 125 and 250 µg/ml respectively. Polio virus type 1 was not susceptible to any of these extracts."
Until now, extracts from Bambusa vulgaris are traditionally very effective in the treatment of measles and helminthic infections while extracts from
Aframomum melegueta are used in the treatment of infections such as cholera, smallpox and chicken pox.
The researchers added: "The outcome of the antiviral screenings of A. melegueta and B. vulgaris was impressive as the extracts possess activity against two of the viruses which were tested. Activity was found in extracts of the two plants. Out of the three viruses, only measles virus was susceptible to the extract of B. vulgaris. The other two viruses were resistant to the extract.
"Extract of A. melegueta was however inhibitory on both measles and yellow fever viruses. Measles virus was inhibited at a minimum concentration of 125 µg/ml and yellow fever virus was inhibited at a minimum concentration of 250 µg/ml. Polio virus was resistant to extracts of both plants. This is a characteristic of this virus. Poliovirus is a non-envelop virus infecting through the gastrointestinal tract and causes poliomyelitis due to its ability to evade the acidic nature of this tract. This is a kind of natural defense mechanism. It is therefore not surprising that extracts of the two plants had no effect on the poliovirus type 1. Although, extract of B. vulgaris was only potent on measles virus in-view of medicinal plant applications, extracts with broad-spectrum activities and minimal cytotoxic effects might be more important.
"It is interesting to attempt to correlate the traditional applications of the plant extracts with the microbial targets. In the case of B. vulgaris, this is feasible since the extract of this plant had activity only on measles virus.
Antiviral activities observed with extract from A. melegueta had a broader activity since it inhibited the growth of both measles and yellow fever viruses. The antiviral activities observed with these plants are most probably due to the phytochemicals in the plants. Such phytochemicals, according to Ekwete (1992) include tannin, phenolic compounds, saponins, flavonoids and protocatectic acid among others. These phytochemicals are known to activate the lymphocytes of infected individual and prevent forming of resistance in viruses and also virus replication (Chiang, 2003b).
"It should therefore be recommended that application of extracts from these plants could help in the treatment of measles and yellow fever infections."
A decoction from the leaves of Neem tops the list of herbal remedies for Chicken pox and other skin diseases. Botanically called Azadirachta indica, Neem also popularly known as Dogonyaro in Nigeria belongs to the Meliceae family. The common tree tops the list of plants that have been scientifically verified to effectively treat chicken pox.
Until now, Neem extracts have been shown to possess anti-bacterial, anti-fungal, potent antiviral and anti-cancerous properties.
Neem has been found to be an effective antiseptic for the treatment of viral infection including small pox. Indian researchers in a study published in Journal of Biological Sciences noted that Neem extracts have been shown to possess potent antiviral properties against different viruses including herpes simplex virus type-1 infection and chicken pox. According to a new study published in the International Journal of Clinical Nutrition (IJCN), there are certain compounds in Neem that demonstrate a unique ability to surround viruses, which prevents them from causing infection.
The researchers wrote: "So depend upon the nature or kind microbes minimum amount required to stop the growth. Neem also inhibits viral multiplication by interacting with the surface of the cells to prevent the cell from becoming infected by the virus. Neem has been observed to be effective against a number of viral pathogens in various clinical studies demonstrating it contains unique properties to inhibit viral disease. Neem is one of just a few known antiviral agents.
"Chickenpox, shingles, herpes, and hepatitis are viral conditions, which have been successfully treated, in clinical studies by Neem's therapeutic compounds. The uncomfortable symptoms of colds and flu's can be relieved during seasonal changes by the regular consumption of Neem Leaf capsules, extract, or tea."
Also, scientists have demonstrated how natural remedies provide cheaper route to prevention and treatment of hepatitis B and C, and indeed liver damage in the country. Top on the list are: bitter leaf, Phyllanthus amarus, avocado, turmeric, garlic, and bitter kola.
Phyllanthus amarus belongs to the plant family Euphorbiaceae. To the Efik it is called oyomokeso amanke edem; geeron-tsuntsaayee (birds millet) in Hausa; Ibo (Asaba) buchi oro, Ibo (Umuahia) ngwu; iyeke in Urhobo; and ehin olobe or eyin olobe in Yoruba.
Botanically called Persea americana, avocado is also commonly known as avocado pear, alligator pear, or mountain pear.
Turmeric is a spice that comes from the root of Curcuma longa, a member of the ginger family, Zingaberaceae. It is called atale pupa in Yoruba; gangamau in Hausa; nwandumo in Ebonyi; ohu boboch in Enugu (Nkanu East); gigir in Tiv; magina in Kaduna; turi in Niger State; onjonigho in Cross River (Meo tribe).
Rev. Fr. Anslem Adodo of Pax Herbal Clinic, Ewu in Esan Local Government of Edo State, had said: "Bring one unripe pineapple fruit, 10 leaves of cashew plant, one handful of cotton seed, 10 bottles of water to boil together. Take one glassful four times daily for 10 days
"Secondly, grind 20 pieces of bitter-kola into fine powder, then mix with one bottle of lime juice and one bottle of honey. Take four dessertspoons four times daily for two months.
"Thirdly, squeeze 40 bitter leaves into four litres of water. Take one glassful thrice daily for two months (make fresh preparation as needed)."
Also, Nigerian researchers have found that water-based extract of bitter leaf (Vernonia amygdalina) could be used as adjuvant in the management of people living with Human Immuno-deficiency Virus (HIV)/Acquired Immune Deficiency Syndrome (AIDS).
A recent study on the immunological effect of Vernonia amygdalina leaf extract and immunace® (nutritional supplement) on HIV-infected patients taking highly active antiretroviral therapy (HAART) found that it could serve as a nutritional supplement in an HIV-infected or immuno-compromised condition such as cancer or diabetes patients.
The study published in Asian Pacific Journal of Tropical Biomedicine concluded: "The aqueous extract of Vernonia amygdalina (bitter leaf) and immunace or both have the immunological effect on HIV-infected patients. Therefore, we suggest that the V. amygdalina extract or immunace or both could be used as adjuvant in the management of HIV/AIDS clients."
The study was conducted by researchers from the Department of Pharmaceutics, University of Nigeria Nsukka, Enugu State; Department of Chemistry, Ahmadu Bello University Zaria; and Department of Pharmaceutics and Pharmaceutical Technology University of Uyo, Akwa Ibom State.
The result of the study showed that the mean absolute CD4 count (a marker of the immune system) was increased in the client who took the extract or supplement. And the clients who took both the extract and supplement had a greater increase in the CD4 count. The increased CD4 was significant as compared with the control group. The skin rashes were also improved in the entire groups.
Also, the World Health Organisation (WHO) and the Food and Agricultural Organisation (FAO) have endorsed some herbs and spices that have shown promise in treating the opportunistic infections associated with the viral infections without side effects.
They have verified the efficacy of garlic (Allium sativum), ginger (Zingiber officinarum), cloves (Syzigium aromaticum), thyme, cayenne, basil, Aloe vera, Neem tree (Dogonyaro/Azadiratcha indica), lemon (Citrus limon), lemon grass (Cymbopogon citratus) in the treatment of opportunistic infections associated with the HIV/AIDS.
A Neem-based product has received United States (U.S.) patent, "US 20070275085 A1", as compositions and methods for the cure of HIV/AIDS.
Also, Nigerian researchers led by a professor of pharmacognosy at the University of Nigeria Nsukka (UNN), Chief Executive Officer of Bioresources Development Group (BDG), and former Chairman of the Independent Election Commission (INEC), Prof. Maurice Iwu, have validated local foods such as bitter kola, coconut oil, bitter leaf, Moringa oleifera, Sour sop, the mushroom Garnoderma lucidum, among others as immune boosters and for the treatment of HIV.
Also, another group of researchers have in clinical trials demonstrated how poly herbal preparations made predominantly with bitter leaf provide cure for chronic form of hepatitis B and C co-infection, cancer, type 2 diabetes, tuberculosis and HIV. The researchers from Halamin Herbal centre, 10 George Innih Crescent, Apo District, Abuja and Department of Histopathology and Cytology, Jos University Teaching Hospital (JUTH) Jos found that poly herbal preparations with bitter leaf as the active ingredient strengthen the immune system through many cytokines and chemokines regulations.
Other constituents of poly herbal preparations include: Sesamum indicatum (sesame), bitter leaf, Aloe barbadensis (popularly known as aloe vera), Saccharum officinarum (sugar cane), garlic and Amaranthus caudatus (green amaranth, inine in Ibo, tete abalaye in Yoruba).
Also, several studies and researchers have touted gin-garlic as the most potent herbal combination in the world. It has been used to treat from heart diseases to tuberculosis. A cocktail of ginger and garlic has been shown to be effective in bursting the cold and influenza viruses.
A United Kingdom research suggests people who take a garlic supplement each day are far less likely to fall victim to the common cold than those who do not.
Also, other Nigerian researchers have also demonstrated that local species can be successfully used to beat the viral infections.
The spices include: pepper fruit; African pepper; scent leaf; thyme; onion; garlic; nutmeg; Benin pepper; black pepper; wild pepper; curry leaf; chilli pepper; red pepper; grains of paradise; and ginger.
A study by Ndukwu B.C and Ben-Nwadibia N.B of the Department of Plant Science and Biotechnology, University of Port Harcourt titled "Etnomedicinal aspects of plants used as spices and condiments in the Niger Delta area of Nigeria" found 23 local spices to have varying therapeutic applications by the local communities.
Their uses in ethno-medicine include acting as stimulants, antiseptic carminatives, expectorants, laxatives, purgatives, anticonvulsant, antihelmintic, and sedatives to the treatment of diarrhoea, malaria, rheumatism, asthma, catarrh and bronchitis.
The study observed that the indigenous people value the plants more for their ethno-medicinal uses than for spicing foods. For instance, ginger is more valued for its treatment of coughs, asthma, colds and hypertension than as condiment.
Garlic (Allium sativum) is of plant family Liliaceae. Local names: Igbo - ayuu; Yoruba - ayu. The bulb is used for fevers, coughs, constipation, asthma, nervous disorders, hypertension, ulcers and skin diseases. It is highly bacteriostatic (stops the growth of bacteria), fungicidal (kills fungi) and antihelmintic.
According to the study, crushed garlic (soup) is used against microbial infection, asthma cough and respiratory problems. The juice of the bulb is given as ear-drops against earaches. As a seasoning and flavouring agent, garlic is principally taken against fevers and chills.
A cold infusion serves as a body-wash for infants as protection against chills. The bulb also serves as effective remedy for hypertension, muscular pain, giddiness and sore eyes. It is digestive and carminative and removes pains of the bowels. When powdered with nation it is applied as a dressing on ulcers and skin diseases.
Before now, garlic has been traditionally used to fight-off and treat the symptoms of the common cold.
A United Kingdom study found that a daily garlic supplement containing allicin, a purified component of garlic considered to be the major biologically active agent produced by the plant, reduced the risk of catching a cold by more than half. It also found that allicin-containing garlic supplements were effective in treating infections caused by the hospital superbug, Multi-drug Resistant Staphylococcus Aureous (MRSA).
A total of 146 volunteers took part in the experiment, which was led by Peter Josling, director the Garlic Centre in East Sussex, United Kingdom.
Half took one capsule of Allimax, an allicin-containing garlic supplement, each day, while the remaining volunteers were given a placebo.
Over a 90-day period during the winter when most colds occur, just 24 colds were recorded among those taking the supplement, compared to 65 amongst those taking the placebo.
The study also found that those taking the supplement who did catch a cold were more likely to make a speedier recovery than those taking the placebo and the chances of re-infection following a cold were significantly reduced. Josling said the results of his research could revolutionise future treatments of the common cold.