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Opinion

Book on Rabies for the public – by Prof. Nimal Senanayake

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Reviewed by Prof. N.A. de S. Amaratunga PhD, DSc

Prof. Nimal Senanayake MD, PhD. DSc, FRCP, professor emeritus, eminent neurologist and creative writer and producer of drama and films, continuing his commitment to write in Sinhala on important health issues for public education, has published the 17th in the series and the chosen subject is the deadly Rabies of which the public awareness could be insufficient from the point of view of prevention and treatment to prevent death. Prevention of onset of the disease is not difficult if treatment is instituted soon after a dog bite or bite by other animals, like bats carrying the virus. Prof. Nimal Senanayake (NS) deals with these aspects adequately and in simple prose in his little book of 165 pages.

NS showing his proclivity to drama and suspense starts in dramatic fashion, bringing in bats rather than dogs to begin his story describing cases of rabies in Texas 1951, Florida 1953, and Pennsylvania 1953, all due to attacks from the sky, as it were, all bitten by flying bats coming down and biting without any provocation. All these bats were not blood sucking vampire bats but apparently harmless insectivora. NS’s intention clearly is not just drama but to draw the attention of the reader to the strong possibility of bats developing as vectors of deadly viruses as was the case with Corona and several other virus diseases which NS has written about. NS has mentioned that Rabies following bat bite had occurred in Sri Lanka, too.

NS then embarks upon a very interesting journey, through history, starting with Diana the Roman Goddess of Wilderness and the Hunt, and traces back the history of Rabies to 4000 years. He mentions great philosophers Democritus (500 BCE), and Aristotle (384 – 322 BCE) and the father of medicine Hippocrates, who had written about disease due to animal bites. Greek physician Galen (129 – 200 CE) had recorded the natural history of rabies and also treatment measures, including wound care, some of which are still valid. NS has commented on Arabian writings on rabies which is noteworthy as early development of medicine happened in the Arabian civilisation.

After history, NS switches over to his usual practice, adopted throughout this series,where he asks critical questions and gives lengthy explanations. These questions are those that may arise in the minds of science writers, students, patients and ordinary people. They are designed to bring out the most important information that these categories must know about rabies and also lively anecdotes. This is a very effective and efficient method of conveying the knowledge with brevity and clarity, that the author has developed with his vast experience of teaching and practice of medicine.

Beginning with the virology of rabies, with a description of the rabies virus, the author covers the entirety of all aspects of the disease. He connects up the physiology of the virus with the pathogenesis of the disease, how the virus enters the tissues of the human body, proliferates and then gains access to the nervous system through the peripheral nerves. What happens in the brain, when the virus reaches it and affects the brainstem, limbic system, etc., would be of particular interest to the medical students.

How the author looks at every aspect is exemplified when a question is asked whether the person who attends to the wounds of the patient could contract the infection and the explanation that follows showing how it could happen. Then the author explains why and how rabies is known as hydro-phobia, the horrendous result that ensues when the extremely thirsty patient attempts to take some water into the mouth and try to swallow it is the reason that causes severe fear of water in the mind of the patient. The physiological basis for this undue fear of water, according to the author, is ‘conditioned reflex’ and this is illustrated with the famous experiment by Pavlov and his dog. Similarly, the patient is horrified of the wind blowing against his body which, like water, causes severe shivering and muscle contraction. A comprehensive description of the possible animals that could be a vector for rabies is given and also how careful people should be about their pets and the danger of being suddenly attacked by these animals who may appear to be harmless, is vividly described.

Though these symptoms are seen in the advanced state, the early symptoms could be similar to those of common cold except that there could be radiating numbness at the site of the wound. The wrong beliefs that the patient may bark like a dog or even bite others have no basis and the origin of these beliefs is explained. But the caregivers must be careful not to get contaminated by salivary secretions of the patient, even on a minor wound or scratch on their skin.

The tragedy of the situation is that when the patient is not subject to severe muscle contraction and shivering he could be in his proper senses and he realises that he is facing a horrendous death. This state is really pathetic for everybody near and dear to the patient. Physio-pathological explanations of the often mysterious fearful clinical picture would be very useful to medical students. These fearful clinical features could be to some degree controlled with pain killers and sedatives. Apart from the nervous system other organs also may be invaded via the nerves and consequently heart failure and pneumonia could result. Merciful death would arrive with the patient going into coma due to the development of encephalitis which is not any different from other types of encephalitis.

After this comprehensive discussion on all the important aspects of rabies, the author talks about a rare type of rabies called paralytic rabies which is due to the spinal cord and the medulla oblongata being affected instead of the brain and brain stem. This condition is also known as the dumb or silent rabies as there is no violent spasms but a paralysis of limbs and other muscles. Yet slow death cannot be avoided. This type of rabies is more common with bat bites and there had been an outbreak of it of epidemic proportion in Trinidad in 1929 – 1931 period. Health authorities thought it was an outbreak of polio or botulism poisoning.

Author goes into details of diagnosis and draws our attention to the fact that the animal bite incident may even have been forgotten as onset of symptoms could be delayed. This makes diagnosis difficult and this is made worse by the fact that there may be several other conditions that may initially exhibit similar clinical features. NS with his usual thoroughness mentions that sometimes a person who has been bitten by a dog may undergo immense mental stress and go into hysteria which may simulate rabies!

NS gives a comprehensive description of tetanus which is one of the conditions that need to be differentiated in the diagnosis of rabies. Moreover tetanus could occur following bites by dogs and other animals who carry the bacterium that causes tetanus. In tetanus the bacteria do not travel upto the nervous system but the toxin it produces while proliferating in the depth of a wound could travel along nerves and effect the central nervous system. Spasms of muscles could result in a similar clinical picture to that of rabies though there are important differences that may help the doctor to suspect rabies. These differences are lucidly described by the author and illustrated with clear colour pictures which is a striking feature throughout the book which complements the text and adds value to the work. The fact that if adequate treatment is provided in good time tetanus could be fully cured which is not the case with rabies which needs to be nipped in the bud if it is to be cured is emphasized.

NS mentions botulinum toxin poisoning which is another condition that could mimic rabies. What is important to ordinary reader here is the fact that contaminated food, specially tinned fish that has gone bad could contain the toxin due to Clostridium botulinum contamination. NS does not forget to tell us how to detect the possibility of such contamination by an examination of the can of fish which would appear to be swollen and the fish would be blackish in colour. Other diseases that the author mentions, which may be clinically similar to rabies, are encephalitis caused by malaria, delirium tremens and poisoning by certain locally found wild fruits like “goda kaduru” and “attana” and also “ganja” which children may unknowingly consume.

Then the author deals with the tests that could be carried out to confirm the diagnosis particularly in the animal that had bitten the patient so that treatment could be started early to prevent death. He has a story to tell about the development of these tests and also the vaccines. He gives detailed account of how Frenchman Louis Pasteur succeeded in discovering anthrax causing bacteria in cattle and attempts at developing a vaccine against anthrax and also against rabies. Description of Pasteur’s attempt to experiment the rabies vaccine he had developed on a human being is full of drama and suspense. Scientific detail which could be boring is embellished with human drama which is a feature of NS’s writings that make them so readable. Author has written several pages on Louis Pasteur in order to emphasize the great importance of the ground breaking discoveries he had made which eventually helped mankind to combat many killer diseases caused by micro-organisms. The description of how Pasteur risks his life when he sucked into a tube saliva from a rabid dog is fascinating.

Next NS deals with the attempt at attenuation of the virus by Irish physician Sir David Semple (1856 – 1937) The attenuated virus could be used as the vaccine as it could initiate the development of immunity against the viral infection. Greater success was achieved by the efforts of Polish physician Hillary Koprowski (1960 -2013) and American bacteriologist Herald Cox (1907 – 1986) who used new methods to lessen the virulence of the virus. Methods of producing safe vaccines which may not have the complications of earlier varieties have taken vast strides with the development of DNA technology.

Finally, NS writes about prevention and treatment of rabies which is of vital importance as about 55000 die worldwide annually mainly due to ignorance, negligence and lack of facilities for vaccination. What should be done after being bitten by an animal which could be a vector of rabies are clearly described. The use of Rabies Immunoglobulin (RIG) and Anti-rabies Vaccine (ARV) and their mode of action is given in detail. This section is very important for the student as well as lay persons. The final chapter on animal management from the point of view of rabies prevention would be very useful for everybody, specially people who keep pets, animal lovers and animal farm keepers.

Prof. Senanayake has produced yet again a compact little book, full of knowledge important for everybody, written in beautiful Sinhala prose, like a story, simplifying complex matters and vividly emphasizing where emphasis is necessary. This excellent piece of work would be of use to ordinary people, medical students, postgraduates, animal farmers, and doctors who practice bread and butter medicine everywhere in the country.



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Opinion

Demystifying Buddhism: Need of the hour?

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by Dr Upul Wijayawardhana

Mystification is undoubtedly one of the most effective techniques adopted by all religions to ensure that their followers toe the line. After all, who wants to go against religion and face eternal damnation? However, the world has moved on since the inception of all religions and now even scientists agree that there is nothing permanent; not even the universe! By the way, impermanence as a key concept was introduced by the Buddha more than two and half millennia ago. At the moment there is global concern over yet another creation of the human mind: Artificial Intelligence!

Some industry leaders are warning that AI would wipe out humanity, joining nuclear war and pandemics which are the leading contenders to do the same. Geoffrey Hinton, so-called ‘Godfather of AI’ resigned from his job at Google stating that the tools he helped create may be used to end civilisation. AI language tools such as ChatGPT are already being used by students to cheat but would someone go a step further and use similar tools to weaponise ‘fake news’ or develop deadly chemical weapons? One can argue that religion can play an important moderating role in preventing such things happening but, on the other hand, it could be questioned whether they can do so if religions are removed from reality by mysticism?

Perhaps, all religions need demystification but I shall confine myself to Buddhism as it is the only religion I know a bit about. Further, I fear any criticism of other religions may earn me the reputation of someone attempting to promote religious discord. We live in a world, which is becoming increasingly intolerant of free speech whilst clamouring for the same! Oxford Union, once the bastion of free speech, nearly stopped Philosophy professor Kathleen Stock from expressing her view that trans women were not women.

Having failed to cancel the event, transgender activists attempted to sabotage her presentation. Interestingly, they did not attempt to challenge her views instead, perhaps because they are bereft of facts! Though we Buddhists do not do so often, the Buddha gave us the freedom of thought and promulgated the Dhamma by means of discussion. The Buddha was in search of the nature of reality and it perplexes me why and how the religion built around those teachings is full of mysticism. Though it may have served some purpose in the past, my contention is that the time is ripe for demystification.

The month of Poson is of special significance to us, Sri Lankan Buddhists, as according to ancient chronicles Buddhism was formally introduced, on the full moon day of this month 2270 years ago by Arahant Mahinda who was the son and emissary of Mauryan Emperor Ashoka. Though it is very likely that Buddhism spread to Sri Lanka from India much earlier, Arahant Mahinda’s visit resulted in the embracing of Buddhism by King Devanampiyatissa and Sri Lanka becoming a Buddhist country, officially. Arahant Mahinda established Bhikkhu Sasana and as there was a clamour to establish Bhikkhuni Sasana, his sister Sanghamitta followed six months later, carrying with her a sapling of the Bodhi tree, under which the Buddha attained enlightenment. The famous writer H G Wells in the chapter, “The Rise and Spread of Buddhism” in his 1920 book “The Outline of History” refers to this as follows:

“In Ceylon there grows to this day a tree, the oldest historical tree in the world, which we know certainly to have been planted as a cutting from the Bodhi-Tree in the year 245 BC. From that time to this it has been carefully tended and watered.”

Whilst Sanghamitta story tells us that she travelled by land and sea, landing in Jaffna, Arhant Mahinda, who came to Sri Lanka with seven others, including two close relatives; Sumana Samanera, the son of Sanghamitta and Bhanduka Upasaka, the son of his maternal aunt’s daughter, is supposed to have arrived by supernatural means. Is this another instance of mystification! Even if one assumes that Arahants had developed the supernatural power of teleportation, it does not explain how a samanera and upasaka travelled, as an Arahant is not likely to have the ability tag along another person in teleportation.

In fact, Arahant Mahinda’s visit was a much-planned visit and was postponed till the death of King Mutasiva as it was felt that the aging king would not be able to grasp the complex concepts of Buddhism. This makes it very likely that the dramatic meeting described in ancient texts is nothing but a mystification. Anyway, how Arahant Mahinda arrived with others does not matter. What is important is that there is plenty of archaeological evidence to prove that both Arahants Mahinda and Sanghamitta lived in Sri Lanka till their deaths, serving our ancestors. Therefore, they deserved to be remembered on Poson and Unduvap Poya Days, respectively.

The Buddha showed us the way to overcome the sense of dissatisfaction that pervades all aspects of life and also the power of the mind. He showed us the way we could develop our mind and introduced the concept of mindfulness. He showed the path for ultimate detachment. What happened subsequently was converting this Dhamma to a religion by enveloping it in rituals and mysticisms; very practices denounced by the Buddha.

Instead of accepting the Buddha as a normal human being but with an exceptional intellect, he was made supernatural by mystifying his life. He walked immediately after his birth and said it was his last birth. This is mysticism mixed with predetermination but what follows is the truth. In spite of all the luxuries, with increasing dissatisfaction with life, Prince Siddhartha leaves lay life in search of the underlying cause of dissatisfaction. He experiments with extreme torture to the body, a method very popular among sages at the time, which he finds of no use and discovers the Middle Path, the Four Noble Truths and the Noble Eightfold Path.

The Buddha walked the length and breadth of India barefoot, washing his feet himself, when he entered a house. This message of simple living dedicated to the service of others is distorted and some of the Sangha today live in the lap of luxury and indulge in every activity the Buddha advised them against.

The Buddha’s Dhamma explains a path to tread on, and studying how he explored the mind to arrive at this itself gives so much academic satisfaction. Teaching this would ennoble our youth but what is often heard in Bana preachings or lectures are mystical stories or gross distortions, the best example being Dana: giving is a means to getting rid of attachment but is portrayed as a means of guaranteed returns thus increasing greed. I can go on and on.

If Buddhism is to survive, we need to understand and practise what the Buddha taught. The first step in this process is demystifying it so that we may understand the true nature of things.

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Opinion

Artificial intelligence and reality of life

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by Dr D. Chandraratna

Ever since President Ranil Wickremesinghe announced his desire to use Artificial intelligence (AI) to develop all sectors, from banking to agriculture, in Sri Lanka several correspondents have enthusiastically endorsed those sentiments in the print media. There is no gainsaying that technology has already made huge inroads into our lives, the latest paradigm adopted and articulated by the developed countries is thrust upon all mankind as the harbinger of a beautiful new world. Just as in an earlier time when the liberative potential of science created an understandable anguish about its misuse, similar forebodings are felt about the future curated by the super machines. Though unlike in the earlier debates where the misuse was calculated in terms of unlikely human catastrophes the current anguish is more about its ever -present transformative potential of the human world.

Most of the developed countries in the Western world, and Australia have launched statutory guidelines in the ethical use of AI. The Chat GPT, it has been cautioned in some quarters, poses such a risk to humanity that it must be subject to stringent regulation as nuclear power. Open AI founder Sam Altman has said that within a decade AI system would be capable of exceeding human expert skill levels in every domain. Given its possibility to be powerful than all other technologies experts predict that AI poses an existential risk like nuclear energy and synthetic biology. Silicon Valley experts are talking the need for a global regulatory body like the international Atomic Energy Agency (IAEA).

In the field of education, it risks accuracy and reliability of knowledge, the sources of information, academic integrity, student learning capabilities ending up with a humanity’s self-perception. Six months after Open AI launched ChatGPT, Australian University teachers have stated that they are unable to prove students who cheat with AI because still there is no regulatory body. At a conference held in Sydney last week Senior academics have railed against AI as ‘a tool in education’ because of ethical concerns, built in biases, fake knowledge and hate speech. AI is also generating enormous wealth through education in the hands of a few white male billionaires who are living off surplus value created mostly by brown and black workers.

One Deakin University academic has said it is only a data exchange service and an academic from Macquarie University said that ChatGPT app could easily be used by weak students to obtain enough marks to pass examination. Teachers may have to use open assessments and other examination methods to evaluate students. Students may be tempted to undermine their own desire to acquire knowledge in preference to the attraction of credentials to further their career prospects. Given the fact there is in the developed world a phenomenon of ‘degree inflation’ the quality and value of higher education will diminish. If cheating with the help of AI increases one’s chances of gaining the credentials thereby reducing the lure of understanding many students will not scruple to do so.

It is also the case that AI has the potential to make many employment opportunities ‘surplus to requirements’ in the knowledge economy for AI is efficient and cost cutting. Data analytic employment in multiple industry sectors will vanish overnight. Because of the fears of ChatGPT share prices of many education organisations have plummeted overnight. With the announcement of the ChatGPT, US company Chegg, which produces homework study guides, lost heavily on the stock market with more than half its workforce facing retrenchment.

There are other dangers. The value of education as character building, knowing yourself, examining one’s life, becoming wise, which are the wider objectives of education lose their appeal. Education is reduced to a process of credentialising to make us employable. AI is driven by a few mega corporations whose commercial motives are not aligned with the wider purposes of education beyond the why and the how. Education in the AI era will be concentrating on skills for employability. It can change the current paradigm of education. AI has the potential to cultivate a narcissistic and misguided anti-intellectualism which can shut out reasoned debate on public issues.

This existential threat to our sense of personal autonomy and human agency cannot be ignored. We must legislate to protect those aspects of humanity that are exclusively human and vitally important to the functioning of democratic communities. We should be alert to the fact that AI cannot replace nuance. It is soulless, cannot feel pain or loss, has no heart and no intuition. AI like all replacements to the original will disappoint us at the crucial hour for it cannot replace years of experience, innate ability, and intuitive wisdom.

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Opinion

Palm oil growers await green light for sustainable production

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A young oil palm plantation having a thick legume cover crop

By Emeritus Prof. Asoka Nugawela

Palm oil is a versatile commodity. It is used in numerous products world over. The global usage in 2022/23 is estimated as 76 million metric tons. Accordingly, the average global per capita usage is in the range of 10 kg per annum. Sri Lanka too recorded similar usage during 2018/2019 period, prior to economic downturn in the country. Palm oil usage is very much higher than the usage of other vegetable oils such as coconut, soya, canola, sunflower, rape seed and olive. One major reason for the relatively high per capita usage of palm oil is the affordability to purchase and its availability. Per unit land area, the oil production is four times greater in oil palm when compared with coconut. When comparing with other crops grown for vegetable oil production it is about tenfold higher. Further, oil palm, coconut and olive are perennial crops whereas soya, sunflower, canola and rape seed are short term crops. With short term crops the capital cost component is relatively high with yearly land clearing, land preparation and planting activities to be undertaken. Oil palm with a high oil yield and having a 30-year economic life cycle has the ability to provide a relatively cheaper vegetable oil than from other crops. With perennial crops the disturbance to the soil properties and biodiversity is less than in annuals and is a positive attribute as far as sustainability is concerned.

One other reason for palm oil to be the preferred vegetable oil is because it contains both saturated and unsaturated fatty acids in almost equal proportions. Thus, it is different from coconut and other vegetable oils which contain a relatively high percentage of unsaturated fatty acids, around 90%. Palm oil with its 1:1 balance of saturated and unsaturated fatty acids is the preferred choice for many applications in the food industry.

Both the type and the number of fatty acids of fat in our diets are known to influence health and wellbeing. The present global advice is to increase the consumption of unsaturated fatty acids at the expense of saturated oils and fats. For optimal health we require a mixture of fatty acids to be present in our diet. In this context among the sources of dietary oils and fats palm oil could be viewed as a relatively better option for its ‘mixed’ fatty acid profile (saturated, mono and polyunsaturated fatty acids).

The relative advantage in the return on investment the oil palm crop is having over other plantations crops also drives the investments towards this crop. This is true for both plantation and smallholder sectors in major palm oil producing countries in the world. The profitability from different plantation crops grown in Sri Lanka under average management conditions and current agrochemical/material costs & trading conditions are summarised in Table 1. Accordingly, oil palm is by far the most profitable plantation crop in the country. (See table)

The country has a demand for palm oil as a cooking oil and also as a raw material for many other industries. The products made in these industries are essential and widely used. For vigorous growth and high yields oil palm crop should ideally be grown under tropical climatic conditions with more than 2,500 mm of rainfall per annum. The low country wet zone of the country is blessed with such climatic conditions. The return on investment is high with this crop. However, even under such a favorable business environment for this industry, the government of Sri Lanka has taken a decision to ban cultivating this crop in the country. All other palm oil producing countries in the world, i.e., more than 20, are surprised and view this as a wrong decision.

Some repercussions of this decision to ban oil palm cultivation in Sri Lanka are a). dependency on other countries to fulfill our vegetable oil need, b). loss of foreign exchange to the country by importing palm oil, c). loss of income to the potential investors, d). loss of employment opportunities and e). depriving potential smallholders, the opportunity to enhance their livelihood. Prior to the economic crisis in this country, around 200,000 MT of crude palm oil (CPO) had been imported annually. The current global market price of a metric ton of crude palm oil is around 900 US$. Thus, the foreign exchange requirement to import national crude palm oil requirement will be more than 180 million US$ per annum without freight and insurance costs.

In the past, forests have been felled to cultivate oil palm in some major palm oil producing countries. The same approach was adopted for planting other plantation crops as well in the past. Deforestation will invariably lead to further shrinking of already depleted forest cover and loss of environmental services we accrue from natural forests. Natural forests significantly contribute to depleting of greenhouses gases, to the natural water cycle and protects biodiversity, soil, catchment areas, rivers and water bodies. Due to serious negative impacts of deforestation on the environment, a worldwide lobby demanding countries to grow oil palm in a more sustainable manner was initiated. With this lobby changes are now taking place in the manner in which land is selected to grow oil palm. For most crops including oil palm, systems to certify sustainable plantation management have evolved and such certification has become a requirement for marketing of produce from plantations. Basically, issues related to cultivating oil palm had been identified, awareness created amongst parties concerned and interventions for rectification have been put in place. In Sri Lanka however, to start with there was no issue of deforestation associated with oil palm cultivation. The land for cultivating oil palm in Sri Lanka was obtained through crop diversification, a scientifically accepted approach. Even then cultivating of oil palm in Sri Lanka was suddenly banned by the government incurring the investors a loss of more than Rs. 500 million on nursery plants alone. The global lobby was against felling forests to plant oil palm. The reasons for the anti-oil palm lobby in Sri Lanka according to some environmentalists, scientists and politicians are negative impacts to the environment, loss of biodiversity, depleting soil water and threat to the existence of other plantation crops. There is no scientific basis for such allegations. But those who lobby against planting oil palm do not want to understand the difference between ecological impacts when planting oil palm subsequent to felling natural forest cover and as a crop diversification program. Various attempts made had been futile and as the Sinhala saying goes it’s like trying to wake up a person who pretends to be sleeping.

The necessity for a country to produce its own needs is more than evident now with the economic crisis the country is facing currently. With a huge disparity in outflow and inflow of foreign exchange to the country the need to produce our own requirements are very much obvious. As explained earlier in this article Sri Lanka has a conducive business environment for a successful palm oil industry. What is lacking to drive the industry forward in the country is the political will. Politicians may be fearing that a decision to lift the ban on oil palm cultivation will not be a popular decision affecting their vote base. Countries economy is currently shrinking leading significant losses in employment, falling income levels, increased inequality and government borrowings. To recover from such an economic crisis the country should not ignore viable industries that could enhance national production. A reversal to the decision to ban oil palm cultivation will lead to producing national requirement preventing the outflow of millions of dollars each year. Revenue moving out will circulate among all stakeholders of the industry helping to enhance their livelihood and strengthening the economy of the country.

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