Genome editing: A game changer for cassava improvement in Africa
Nairobi, Kenya 28th April, 2021:-Genome Editing for crop improvement and biofortification has been a game changer in Africa for staple foods and cash crop improvement. Many developing countries are applying the cutting-edge technologies, such as genome editing, to improve especially cassava micronutrients, starch content, yields and seed systems.
Dr Ihuoma Okwuonu, a Plant Biotechnologist and Chief Research Scientists at the National Root Crops Research Institute (NRCRI) in Umudike, Nigeria, while speaking to journalists during a press briefing by Africa Science Media Center, expounded on the genome editing technique.
The Chief Research Scientist explained genome editing is simply rewriting the genetic information of living organisms to create new abilities, correct abnormalities and improve performance. She pointed out diseases and pests such as bacteria, viruses, fungi which affects cassava both vegetative and the
roots parts resulting to low yields.
“There are two reasons why we are promoting genome editing; one is to improve cassava to withstand some of the impact of diseases. Example is the Cassava Bacterial Blight (CBB) disease. So, with genome editing it is possible to identify the gene, study it, use gene editing to remove the susceptibility gene within the cassava crop,” Dr Okwuonu explained.
“The second goal is to use gene editing to develop disease monitoring tool to monitor disease progression and stop its spread. We can use gene editing to make a change or deletion in cassava or include/ attach any signal to help us study any effect in cassava,” the Plant Biotechnologist emphasized.
However, she noted with regrets several other factors that affect cassava production in Africa, making it difficult for farmers who grow cassava to generate income. This subsequently affects several people depending on cassava as their source of food.
She said the use of conventional breeding to improve cassava present a lot of bottlenecks that come with breeding cassava and long period for developing new varieties. “It takes between 8-15 years using conventional breeding method while genome editing reduces the period,” Dr Okwuonu regretted.
Expert Reactions to Drugs for Neglected Diseases and Impacts of Covid-19 Pandemic
Dr Monique Wasunna, the Director Drugs for Neglected Diseases initiative (DNDi) Africa, said:
“There are over one billion people affected by Neglected Tropical Diseases (NTDs) worldwide. Approximately 500 million of those affected are children, while at least 1 in 8 people suffer from one of the neglected diseases,”
“Most of the NTDs are a group of preventable and infectious diseases that affect the marginalized and poor populations living in remote areas, urban slums, or conflict zones all over the world. They are generally referred to as neglected diseases owing to the little financial incentive to support desperate need for medical research and innovation to bring news tools to help such cluster of people,”
“As a result of this financial mismatch, about 1.7 billion people worldwide are affected by NTDs. Almost every country worldwide is at least infected by one of the NTDs. At least 40% of the global burden of the NTDs is on African continent,”
“Since NTDs are diseases which are neglected, there are very few treatments that exist for neglected patients. And even if there is, the treatment could be toxic (not safe) and low cure rate and effective yet again with minimal options available to access,”
“Countries in other continents may have the NTDs but fewer compared to Africa with most countries having at least six of NTDs. In the previous years, many researches have been carried out on NTDs were unsuccessful showing lack of research and developments,”
“Before 1991 to 1999 a desk review showed there were 1.1% of at least 1,393 new treatments brought to the market in between 1975 to 1999 were for NTDs representing 12% of the global disease burden. A follow-up 10 years later, thus in 2000 and 2010 another review was done and it showed that 4% of the new drugs were for NTDs,”
“Chemical entity, a drug that started from a scratch and developed gradually through pipelines until it’s ready for human use. So, the new chemical entities were just 1% again showing lack of research and development,”
“Currently there is less than 0.5% of the 88 000 drugs in the global innovation pipeline targeting NTDs even though they represent more than 10% of the global disease burden. About 90% of Research & Development being done are for diseases that affect only 10% of the population hence an ineffectual imbalance. This is reason for DNDi establishment to respond to the frustration of clinicians and the patients,”
“To date DNDi have been developing new treatments for people living with neglected diseases. Thereby acting in the public interest, thus bridges existing R&D gaps in essential drugs for NTDs by initiating and coordinating drug R&D projects in collaboration with the international research community, the public sector, the pharmaceutical industry, and other relevant partners,”
“So, DNDi as none profit drug and research & development organization, aims at saving lives and improving the health of people living with neglected diseases by using an alternative model to develop drugs for these diseases, and by ensuring equitable access to treatment around the world,”
“Since 2007 to date, at least 8 new treatments have so far been delivered by DNDi. For instance: ASAQ, which is a new combination to simplify malaria treatment (2007), ASMQ for malaria used in Africa and Asia (2008), NECT for sleeping sickness (2009) SSG+PM Visceral leishmaniasis in East Africa (2010), Paediatric benznidazole which is easier and safer treatment for children with Chagas disease (2011), New VL treatment in Asia for supporting disease elimination (2011), Superbooster therapy a more effective treatment for children with HIV who also have TB (2016) and Fexinidazole: a paradigm shift for sleeping sickness(2018),”
“Currently, DNDi is now aiming at a 25 patient-friendly treatments by 2028. By 2025-2027 the target is a radically improved treatment with new chemical entities, all oral for a treatment shift,”
“Misconceptions and myths about NTDs can be a hindrance to effective implementation of control interventions. For example: NTDs are as a result of witchcraft, NTDs are a punishment from God, NTDs are highly contagious, NTDs affect only a few people, NTDs affect only poor people in developing countries, NTDs are untreatable among others misconceptions,”
“The truth is that NTDs are caused by a variety of pathogens such as viruses, bacteria, protozoa and parasitic worms. NTDs persist under conditions of poverty and are concentrated in the developing world; most NTDs are not transmitted from person to person, although there are exceptions e.g., Leprosy and Trachoma,”
“Again just to emphasize about 1.7 billion people are affected by at least one NTD, while LMICs are hit the hardest by NTDs, poor people in wealthy nations aren’t immune. e.g., Chagas & Chikungunya in the USA. Many NTDs are treatable with existing drugs. However, many of the treatments are difficult to administer and inaccessible,”
“Instead of going to the hospital patients visit witchdoctors. For examples, lesions for patients with VL, uptake of medicines is suboptimal, and patients face stigma. Those with NTDs are often stigmatized, not enough attention and awareness about the diseases, not enough R&D for NTDs; patients do not seek treatment and are thus greatly impacted by the diseases,”
“With the outbreak of COVID-19, this has affected implementation of health services including NTDs. The main programmatic areas of disruption are: Slowing down of much needed NTD R&D activities, community-based activities, delays in diagnosis, treatment, delays in manufacture, shipment and delivery of NTD medicines, re-assignment of NTD personnel to the COVID-19 response,”
“These disruptions could increase burden of NTDs, and delay the achievement of public-health goals and while R&D for vaccines is ongoing, it is important to also focus on finding the best treatment for COVID-19,”
Expert Reaction to Covid-19 Cases Management and Vaccine Roll-Out: The Hits and Misses in Rwanda
Dr Menelas Nkeshimana, Head of Department of Accident and Emergency at the Centre Hospitalier Universitaire de Kigali, said:
“Vaccinating one part of the world or one country or one continent is very dangerous because you are giving a chance to the virus in a country that has not been vaccinated as strictly to mutate and mutations by the end of the day are going to be moderate and spill over to different countries and eventually circulate globally and invalidate the efforts that you would have done prior to vaccinate at the rate of 100% in certain countries, so it is going to waste their resources in some way. So it is not about 60% of a country that should be vaccinated, it is 60% of the global population, this should happen at the same pace.”
“One of the problems when you let the virus circulate longer and it gets ahead of you, you can’t vaccinate or quarantine or people cannot follow your measures, then you risk to have variants. The variants will come with different behavior from the first or original virus. They might come as more frequent; they might come prone to evade the immune system. So they are classified in three big categories, one, variant of interest,”
“It means you have identified the variant and the variant has interested you because whenever you compute it and put the scientific data around it you find it associated with problems: high infectability, associated with severity of illness, affected with ability to produce symptoms in children for example, which was different from the original virus. Once it does interest you, you list it and put it aside. You categorize it as a variant of interest. As of yesterday, we have three variants in this category B.22.214.171.124 which was first identified in New York in November 2020, B.126.96.36.199 which was first identified again in New York in December 2020 and the third one is B2 which was first identified in April 2020 in Brazil,”
“The second category is variant of concern; it means not only did you find association of it with troublesome situation but now you have the evidence that it does so. It is highly infectious, it is highly transmissible, it is leading to severe cases, it is leading to death. Once you have that scientific evidence, you categorize it as variant of concern and in this category we have five strains. One is B.1.1.7 which has been identified in the UK and is called the UK strain, second B 1 which was identified in Japan and Brazil, B.188.8.131.52 first identified in South Africa and we call it South African strain, B.184.108.40.206 which was first identified in US, California and B.220.127.116.11 which was first identified in US, California,”
“So these are the five variants of concern which any country has these variants in a way or another, for example in Rwanda, we have found two of the variants of concern among the travelers who were coming into Rwanda. Fortunately, enough, as per the protocol in Rwanda, any travelers coming from abroad is isolated upon arrival and PCR test is repeated. So these people did not interact with Rwandans, so these variants remained with these people who were quarantined and did not spill over, this was the UK strain and the South Africa strain,”
“Then there are variants in the third category, variants of high consequences. It means they lead to disaster, your vaccine can’t address them, they can evade your immune system leading to high immortality rate, they are leading to very high infectious process beyond what you can contain and usually you should be able to suspect them in countries that are struggling massively with the third wave like high number of people, high number of deaths, uncontrollable disease despite the number of instalment of quarantine, isolation measures and vaccination roll out,”
“Once we have a country with that behavior usually the world health authorities would call up on you to sequence the strain so that you might check if you don’t have variant of high consequences. We don’t have yet as of today but we have variant of concern that may end up in this category anytime from now.”
“A vaccinated person can still get COVID-19 and transmit it and that’s why a vaccinated person should be responsible enough to ensure all the measures are still applied- the distancing, the washing and the facial masks. Being vaccinated, only give you the guarantee that you will not get severe disease and die from it but you can still get it and you can still transmit it; so don’t hug or carry or jump at someone just because they have been vaccinated because they could still be having COVID-19 carried by them.”
EXPERT COMMENT ON COVID-19 VACCINE AND MYTHS
Prof. Phelix Majiwa,Virologist and Professor, Faculty of Veterinary Science at the University of Pretoria, South Africa,said:
“I am very familiar with majority of the vaccines that are used in controlling animal diseases in Africa, the processes they go through from discovery, up scaling, approval and use in the field. So, I can talk quite authoritatively about vaccines whether they are for humans or whether they are for animals.”
“I would like to insert a small disclaimer here which is I think is significant. I do not have any financial interest in vaccines that are being manufactured for any of the diseases specifically for COVID-19. So I’ll make this presentation to you very objectively and I hope everybody understands that there is no commercial interest that I have in making this presentation.”
“So the ‘S’ protein is on the surface of the virus. The virus itself is a very simple organism made up of a very small number of molecules or a very small number of parts. I’m just calling your attention to two parts here. The first one is the ‘S’ protein the next one is the one that’s on the inside and that’s the RNA which is complex with protein.”
“Given the nature of this disease and its effects, scientists have worked very hard based on prior knowledge and tools they have to find vaccine candidates that most likely will help in controlling this disease,”
“The number of vaccines available is quite impressive and remarkable in a way given how recently this disease appeared. There are a number I would like to point to you here that are from Pfizer BioNTech, Moderna and Oxford AstraZeneca.”
“These at least in the west are the three vaccines that are called the leading ones because applications for approval have been submitted to authorities and some of them have been approved. There are a number of other vaccines that are in the pipeline at different stages you’ll see the ones in phase three. Some are in phase two and three while some are in phase one and two. At this point it is useful to remember that Kenya participated in evaluation at some phase, of the Oxford AstraZeneca vaccine.”
“The one that has been definitely approved for emergency use is the Pfizer BioNTech which is based on messenger RNA and for this particular vaccine, vaccination started both in the UK and the US within very recent times. In the UK on the 7th and in the US on the 14th so just about one week after. There was a lot of excitement particularly when these vaccines were administered for the first to humans.
“The campaigners warn that 90% of people in poorer countries will not get the vaccine in 2021. Although they are here talking about the Pfizer BioNTech vaccine, this statement probably will hold true for the majority of the vaccines that will be approved in the next maybe months. So about 90% of people and therefore quite a good number of developing countries may not have access to these vaccines.”
“I would say in most instances they are mixed up with half-truths but nonetheless people read them and pay attention to them because of its effects otherwise had they not have such effects, they would not be posted on a continuous basis anyway. There is a real concern that these messages are reaching Africa and could have negative impacts. The consequence of these messages is that they somehow shape public perceptions of these vaccines, resulting in reluctance or refusal to be vaccinated.”
“Professionals with required information on vaccines and vaccination and disease control should also join this work. Obviously community leaders as well because they are the people who are very much on the ground and leaders should be involved.
“With this misinformation widespread, I think we as Africans should make sure that they do not take root and if they do take root, they could be disastrous in many respects. One, they could make vaccination against Covid-19 very difficult, much more difficult than it is already, compounded by other things and the consequence is that safety and health of the continent could be compromised.”
“This will have not just direct health effects but could also have effects on people who travel, people who do commercial activities with the rest of the world and therefore it could spill into economic ramifications.”
“As I said earlier, these pieces of misinformation are very many but they can be grouped into a number of categories. There are some which are directed at vaccines in general, so a vaccine for any disease whatsoever, then there are some addressed to specific vaccines and others are addressed to specific companies that manufacture vaccines or they could be directed against an individual even if they are only remotely connected to a vaccine or vaccines.”
“I must say here that a very significant proportion of the misinformation is coming from church leaders unfortunately either because of their faith or because in one way or another. They oppose the use of vaccines but that is the truth that a lot of misinformation comes from people that are in the group that can be classified as faith leaders.”
“So, the information required should be objective and balanced, it should be based on science underpinning the vaccines and should be appropriate and relevant for the readership but should not be selective. In other words, one should not select and present only the positive or the good parts of the information, which is required, but nonetheless should rather present in totality and have it in a language that is understandable and it should be appropriate and obviously respectful.”
“It shouldn’t be presented in a patronizing manner and I think, this can best be done by people who can be trusted by the readership. There is often presentation of information by other people with whom the readership cannot identify and I doubt if those pieces of information can be very useful if the reader or the hearer does not trust the person who is giving the information.”
Dr. Jeremy Gitau,Chair Covid-19 champions response team,Kenyatta University Teaching Referral and Research Hospital,said:
“One thing I can say about Corona viruses is that they are not new viruses. They have been there. They have actually been causing about 30% of common colds that we actually experience even before we had COVID-19. So it is not a new group of viruses actually. In this group there are also other viruses like the SARS-coV, there is another one called MERS and if you remember sometimes back there were actually outbreaks of the MERS and the SARS infections that lasted only a few months but also caused a few number of deaths across the world. So it is important for us to know this.”
“As more vaccines come in, the phases will overlap. The vaccine is given as an intramuscular injection; that is IM. You are injected on what is called the dented muscle, on your outer side of your left side, that’s the recommended area, and the dosage is 0.5mls.”
“We usually give two doses, 8 weeks apart. Once you get the first dose, you have to get the second one in 8 weeks. We encourage people to get the second dose as it comes in as a booster dose for the first dose that you got.”
“One thing about the vaccine is that it prevents one from getting severe form of the disease. So it doesn’t prevent one from getting an infection. You can actually get the virus but the body already has immunity and that’s how it’s able to fight it. Because it doesn’t mean since you have been vaccinated it does not mean you’re not going to get the virus infection.”
“Its true Moderna and Pfizer when you look at their rate of protection is a bit higher as compared to AstraZeneca. However, the challenge as I said has been on how to store them as some of them require up to negative 80 to negative 86 degrees centigrade to store them which we do not have the capacity at the moment. So even if we were to bring them they will not actually help us. Remember these ones you need to get the vaccine when it’s active. Otherwise f you store them in the wrong place they become useless. That’s the main reason as to why we chose AstraZeneca. One thing I must say about vaccines is that you are targeting to immunize as many people as you can. That is to prevent them from the severe form of the disease. That is the same thing that has been applied with other vaccines.”
“My suspicion is that as we move forward, the pandemic goes down then there’s a likelihood that the vaccines will be introduced to the national CEPI program. So it’ll be standard thing where people receive it even among children. But also wen new strains come up, and new vaccines against the new strains are developed I’m not sure or I wouldn’t know if the government will still be giving them for free unless the pandemic that continues then probably they would be charged. But at the moment all vaccines are free.”