The 4 Rs: A Breakthrough to a Clean Malawi!

Authors: Chiwona B., Ganiza Y., Paseli P. Themuka M.[1]

trash

Maximise Efficiency, Minimise Waste

In future, waste management is expected to become more difficult and costly for both the government and city residents if population growth and urbanization trends are not properly checked. In recent years the country has seen rapid population growth which is currently at the rate of 2.9 %, as reported by the National State of Environment and Outlook Report of 2010. 86% of the population lives in rural areas and these people are primarily dependent on subsistence agriculture. Nearly 60% of this group cultivate less than 1 hectare of arable land and over time there has been a decrease of the rural population due to migration to urban areas.

As population continues to increase it is necessary to employ techniques which will improve waste management in the country to ensure a healthy living and working environment for the citizens. Government is making a lot of strides in its efforts to curb waste nuisance in the country. Among others, the country has adopted the 4 Rs approach to waste management which calls everyone to Refuse, Reduce, Reuse and Recycle waste.

A study conducted by Leadership for Environment and Development (LEAD) Associates in low income urban areas of Lilongwe and Blantyre cities in 2011 revealed   that the problem of managing waste is poor and inefficient in urban areas where many low-income populations live. Even when a collection service is provided in such areas, the quality, and coverage of the service is much lower than that made available to middle and high-income areas due to many factors. Two important reasons are that these communities usually evolve without any type of planning therefore making it difficult for waste collection vehicles to reach. Secondly, these communities are often illegal settlements who generally do not pay any municipal taxes, which can be ploughed back, into the required community services such as waste management.

The 4Rs Approach

transition

Refusing or avoiding waste involves preventing and minimizing waste production in production systems. This can be achieved by use of less material in production and designing long lasting products.

Reducing is characterized by minimizing waste production through behavior change. This includes transaction to more paperless systems, avoiding consumption of water from plastic bottle and banning of thin plastics.

Reusing mainly focuses on use of already used materials to prevent introduction of new waste. Examples are reusing carrier bags, refilling printer cartilages for reuse and reusing used beverage bottles.

Recycling which is sometimes referred to as recovery promotes a culture of processing used commodities or waste materials into new resources or commodities. Some of the processes under this include use of animal dung to produce biogas, processing used plastic shoes and utensils into new ones, processing used paper into usable paper and use of food and green waste to produce compost.

In a nut shell, Government appeals to the nation to collaborate in ensuring that the country:

  • Increases the capacity and scope of waste management programmes
  • Improves and extend programmes to recycle and reuse waste paper, plastics and water
  • Encourages the conversion of organic waste into compost by setting up demonstration plots and training local communities
  • Increases the coverage of campaigns for improved hygiene and waste management practices

Relevant Literature:

  1. Government of Malawi. (2010). Malawi State of Environment and Outlook Report, Environmental Affairs Department, Lilongwe.
  2. Clean Waste Group, LEAD Associates Cohort 16. (2011). Waste Management Practices in Low Income Urban Areas Study Report.
  3. https://www.commercial.hsbc.com.hk/1/2/commercial/livingbusiness/natural_resource/waste/4RGreen Achievement

[1] Bernadette Chiwona, Blantyre, Malawi. bernadettechiwona@gmail.com

Yasinta Ganiza, Lilongwe, Malawi. yasintaganiza@yahoo.com

Patricia Paseli, Zomba, Malawi. patriciachuma@yahoo.com

Matrida Themuka, Nkhotakota, Malawi. matiethemuka@ymail.com

The 4 Rs: A Breakthrough to a Clean Malawi!

HAVE WE LOST THE WAR?

Malaria elimination threatened by insecticide resistance
Figure 1: Mosquito comfortably resting on the treated nets
Figure 1: Mosquito comfortably resting on the treated nets

Key Messages:

  • Insecticide resistance threaten significant progress on malaria control
  • Fish can be used to eliminate malaria

As Africans, who has never lost a beloved one due to malaria? Will we leave a small creature such as a mosquito to continue depriving us of our loved ones without fighting back? Sure, we have lost many battles but we will not lose this war.

“The widespread of the insecticide resistance among major malaria vector species has become a big issue for countries leading the Malaria Elimination programme”

Dr El Hadji Amadou Niang,

Medical entomologist

Figure 2: A mosquito spraying an insecticide to itself showing resistance
Figure 2: A mosquito spraying an insecticide to itself showing resistance

The battle against Mosquitoes started earlier in the 21st century with some alternative successes and failures. However, the scale-up of vectors control intervention has resulted in major decline in malaria death rate. The level of this progress had led some malaria endemic countries, even those with historically high level of malaria, to consider the possibility of malaria elimination. Unfortunately, mosquitoes are developing resistance to insecticides that threatens the success obtained during this last decade. Indeed, mosquitoes are resistant to at least one of the commonly used insecticides such as dichloro-diphenyl-trichloroethane (DDT). This has been noticed in at least 64 countries  with ongoing malaria transmission, including Kenya, Malawi, Tanzania and Democratic Republic of the Congo.

Figure 3: Resistance on the rise. Can you locate your country?
Figure 3: Resistance on the rise. Can you locate your country?

The widespread use of insecticides has been attributed to the increasing rise of the resistance seen in the malaria mosquitoes. Different studies explained the reasons behind the situation. It has been noted that mosquitoes that tend to be resistant are either avoiding contact with the insecticide or has developed the ability to eliminate the chemicals from their bodies. Another possible reason might be the transfer of the resistance genetic material from the parent to their offspring. Since our core interventions based on the use of insecticides are no longer effective, other alternatives such as the use of fish that feed on the pre-mature mosquitoes are recommended.

Figure 4. Fish feeding on pre-mature mosquitoes
Figure 4. Fish feeding on pre-mature mosquitoes

A cutting edge study was carried out on the feasibility of using fish to control mosquitoes in their breeding sites, opened a new pathway that can be explored in order to recover the battles lost and wins the war. It is known that small fish living in the same habitat with mosquitoes prefer mosquito pre-mature stages to the other encountered organisms.

The study objectives were to:

  • Determine how the fish could be used as an alternative to insecticide based interventions
  • Rear fish for a mass production and to release them where mosquitoes offspring are found
Figure 5: Impact of the introduction of fish in pre-mature mosquito habitat EPS - Expanded Polystyrene and SWAP - Sector-Wide Approach
Figure 5: Impact of the introduction of fish in pre-mature mosquito habitat
EPS – Expanded Polystyrene and SWAP – Sector-Wide Approach

From this study, it is evident that the introduction of fish in the pre-mature mosquito habitats has a significant impact of adult densities and then can be used to control malaria.

Further reading

Chandra, G., et al. “Mosquito control by larvivorous fish.” Indian Journal of Medical Research 127.1 (2008): 13.

Pyke, Graham H. “Plague minnow or mosquito fish? A review of the biology and impacts of introduced Gambusia species.” Annual Review of Ecology, Evolution, and Systematics (2008): 171-191.

Howard, Annabel FV, Guofa Zhou, and Francois X. Omlin. “Malaria mosquito control using edible fish in western Kenya: preliminary findings of a controlled study.” BMC public health 7.1 (2007): 199.


~El-Hadji, Pauline, Gédéon~

HAVE WE LOST THE WAR?

Are mosquitoes waging a third world war against humans?

by
Majamanda James, Ohia Chineyenwa, Bisi-Adeniyi Tolulope, Kumwenda Save

Mosquito in combat
Mosquito in combat
  • Malaria-infected mosquitoes bite humans more than non-infected.
  • Genes are linked to food preference in mosquitoes
  • Or4 gene is the prime candidate for human preference in mosquitoes

Just imagine! Mosquitoes, unbelievably small, are almost holding the world hostage, making them the most powerful insects on earth. Mosquitoes make nations fish out money from their pockets to bail out citizens from their bondage. These creatures bite, transmit diseases and constantly remain a nuisance to human beings.

Globally, the cost of fighting this war against mosquitoes is enormous in terms of economic cost. You may not know this but nations are spending billions of dollars yearly to combat mosquito-borne diseases. Interestingly, this is almost equivalent to the amount USA spent on Vietnam war in the 1950s and the Gulf war combined! We actually thought we were winning the war against mosquitoes until it was recently discovered that mosquitoes have developed their own weapon of resisting our major weapon of mass destruction (which is chemical control). Their weapon is very sophisticated that it is making scientists stay in the laboratory both day and night!

Right now, there is a crisis on our hands because we do not have any other strong weapon of war against mosquitoes. We need to understand how these mosquitoes have been able to maintain a strong position in the battle field in which we undoubtedly thought we had the upper hand.

Over centuries, mosquitoes have played a hide and seek game by evolving to be better carriers of human diseases and this evolutionary process has led man to suspect a foul play. This has led mankind to come up with plan “B” with the need to better understand the mechanisms of mosquito preference to host. Before now, there were assumptions that mosquitoes are drawn to humans based on smell emitted from individuals – “the mosquitoes, cheese and body odor story”. This feature therefore looks at scientifically validating the story to better understand why mosquitoes prefer humans.

Are genes linked to food preference in mosquitoes?

This research focused on genes expressed in the antennae of mosquitoes because this form part of their “smell” system and could be linked to their food preference. Three experiments were carried out to distinguish the preference of mosquitoes versus animals.

Guinea pigs are one of the hosts that mosquitoes respond well to and were used in the study. fig 1
It was realized that mosquitoes retained their strong preference for humans in contrast to no or moderate preference for guinea pigs. The experiment also revealed that mosquitoes had evolved a marked preference for human body odor.

Human preference linked to OR gene expression

Based on the findings of McBride et al. 2014, a gene known as OR was highly expressed in the antennae of female mosquitoes. In humans, an odorant, sulcatone is emitted which attracts or repels mosquitoes through the olfactory receptor in the mosquitoes. This was tested in both the humans and animals used to determine mosquito response. Though this odorant is present in other animals, it is higher in humans. It is abundant in the odor of nylon sleeves worn by humans but it is at very low concentration in sleeves worn by guinea pigs during laboratory testing. fig2The result also revealed that this odorant is about four times more in humans than other animals. The researchers suggested that increased of Or4 may help mosquitoes distinguish humans from animals through a more effective sensitivity and have made them to evolve independently to specialize in biting humans and transmitting diseases.

Conclusion

It has thus been established that there is a clear genetic association between gene changes and behavior in mosquitoes and that mosquitoes infected with malaria have an enhanced attraction to humans and their body smell. You can be sure that humans will give anything to get rid of this odorant that tends to make mosquitoes prefer them to other non-humans! There is therefore a need to re-strategize our methods of warfare to better target these enemies of human existence. Mosquitoes must not be given a chance to start a third world war!

References

  • Mukwaya, L. G. Host preference in Aedes (Stegomyia) mosquitoes in Uganda. II. Studies on indoor and outdoor biting and resting behaviour with special reference to Aedes aegypti L. Acta Trop. 31, 165–176 (1974).
  • Dekker, T., Geier, M. and Carde, R. Carbon dioxide instantly sensitizes female yellow fever mosquitoes to human skin odours. Exp. Biol. 208, 2963–2972 (2005).
  • Picture from google images.

This is a feature article about a paper in Nature “Evolution of mosquito preference for humans linked to an odorant receptor- McBride et al., 2014”

Are mosquitoes waging a third world war against humans?

Once a poison, now a medicine

flower
Quick read:

  • A traditional herb known to have both medicinal and poisonous effect has been identified.
  • Researchers successfully extract the active compounds in the plant.
  • Further research to develop a pharmaceutical product.

Five years ago my uncle Robert was visiting Harare from the UK. Having moved to a ‘civilized society’ that must have a vegetable in their meals, he decided to add an onion in his meal. Little did he know that this ‘onion’ he plucked behind our house was a herb that had been planted by my grand-father and had serious health implications.  It was very painful to see my uncle slip from a brilliant doctor into a zombie as the effects of the poison in the herb destroyed his mental health. We could only stand by his bedside as he slowly slipped from hallucinations into coma. Unfortunately he never recovered from the poisoning, and next week we will be commemorating the fifth anniversary of his death. My grandfather always used this herb on me anytime I hurt myself while running around the compound.

This contradiction aroused my curiosity on the double-edged sword – the bushman’s poison. B. discha is a herb found in southern Africa and known by many names from bushman’s herb (English), munzepeti (Shona), Ingcotho (Isindebele). The herb has been used by the African traditional healers for centuries for various ailments ranging from septic wounds to mental illnesses like depression, anxiety and epilepsy. Further the herb has also been significantly used as a male sexual enhancer (African viagra). In a non-medical use it has been used an ingredient to brew traditional beer.

However, cases of poison like that of my uncle are quite common when people lack the knowledge of how or which part of the plant to use for the various reasons. Professor William Pote and his colleagues from the University of Zimbabwe undertook the challenge to better understand the paradox of this herb. Their works reveal very interesting findings that may lead the herb to your nearest pharmacy store very soon.

Professor Tagwireyi and his team extracted the plant juice from plant samples obtained; they dried and ground the plant leave. Through an elaborate laboratory process he team obtained a concentrated extract. Further experiments were carried out on rodent to establish safe and toxic doses. A formal drug development procedure was done to validate the process. An Antedote was identified as Ciprohiptadine. Lab animals were used to check the medicinal efficacy of the extract to reduce hypertension, anxiety, depression, memory loss, erectile dysfunction syndrome and neuropathic pain.

The treatment of B. disticha extract on hypertension and stress level
The treatment of B. disticha extract on hypertension and stress level

The team found that the extract reduced hypertension, anxiety, improves memory and increased libido in experimental animals. Currently the drug has been adopted in standard treatment of livestock animals to reduce stress. Prof. Tagwireyi believes that since the drug is efficient in animals the same may be applied to human beings. Hence forth, he has set up a team to run clinical trials suffering from anxiety and depression disorders. It is also hoped that purification of the extract may result in other compounds that can be used in development of other drugs for animals and human beings.

This research is related to similar work underway in southern Africa which has paid more attention to laboratory experiments. Further, the South African team has also started a program to propagate the plant. This research has been funded by the University of Zimbabwe and Government of Zimbabwe who have committed to fund the project to full development of the product.

This research and other similar work going on in various parts of the world explain the growing interest in the medicinal value of herbs. Public institutions and pharmacological companies have a big role to ensure see the fruition of such efforts. Since it has been widely believed that drugs extracted from herbs will be much cheaper compared to conventional medicine, we hope that there will be advocacy to ensure that the benefits of these drugs trickle down to the poor populations who have been using these drugs over the centuries.


Further reading:

Gadaga, L.L., 2012. Investigation of the toxicological and pharmacological activity of a hydroethanolic extract of Boophone disticha bulb. Masters of Philosophy Thesis, University of Zimbabwe Library (Unpublished results).

Gadaga, L.L., Tagwireyi, D., Dzangare, J., Nhachi, C.F.B., 2011. Acute oral toxicity and neurobehavioral toxicological effects of a hydroethanolic extract of Boophone disticha in rats. Human and Experimental Toxicology 30 (8), 972–980. Gelfand, M., Mitchell, C.S., 1952. Buphanine poisoning in man. South African Medical Journal 26, 573–574.

Mutseura, M., Tagwireyi, D., Gadaga, L.L., 2013. Pre-treatment of BALB/c mice with a centrally acting serotonin antagonist (cyproheptadine) reduces mortality from Boophone disticha poisoning. Clinical Toxicology (Philadelphia, Pa.) 51 (1), 16–22.

Nair, J.J., Van Staden, J., 2014. Traditional usage, phytochemistry and pharmacology of the South African medicinal plant Boophone disticha (L.f.) Herb. (Amaryllidaceae). Journal of Ethnopharmacology 151, 12–26.

Pote, W., Tagwireyi, D., Chinyanga, H.M., Musara, C., Nyandoro, G., Chifamba, J., Nkomozepi, P., 2013. Cardiovascular effects of Boophone disticha aqueous ethanolic extract on early maternally separated BALB/c mice. Journal of Ethnopharmacology 148, 379–385.


~By William, Edwin, Blessings and Lateefah~

Once a poison, now a medicine