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How pandemics originate and evolve

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By Prof.Kirthi Tennakone

National Institute of Fundamental Studies

History tells us pandemics have devastatingly interrupted civilizations. They killed millions of humans and brought forth misery and poverty, but never wiped out a civilisation. Epidemics and pandemics begin, escalate and wane or re-emerge. However, the causative agent rarely disappears; it opts for a less vicious coexistence. Smallpox is the only epidemically potent disease that has been eliminated absolutely – not via natural processes but by the intervention of human intelligence.

Life has been created by natural forces endowing an essence for it to reproduce and undergo change. We ourselves and the virus exist because of this, which also enables the virus to adapt itself to the environment, survive and expand causing the pandemic. In ancient times, humans had to await the consequences of the same natural forces to face a pandemic – those who remained fit and immune survived and reproduced.

Today, human intelligent intervention makes things more favourable to us than to the virus, and helps many who lack the natural immunity survive. The eventuality of the present pandemic will be determined by the effort we make to combat it.

 

How pandemics originate

Persian philosopher Ibn Sina was probably the first to conjecture that living entities in the human body caused diseases. Later, Louis Pasteur proved infections occurred when microscopic organisms entered the body and proliferated and those microbes could pass from one individual to another.

Microbes do not emerge spontaneously; nor do they arrive from the sky. They exist everywhere in the environment as creations of biological evolution. Humans, animals and plants harbour them. Microbes associated with a given species, often symbiotic, pose no danger to the host, whose immunity prevents their undue proliferation. They are selective; those present in one species would not easily move to a different type of host and get established. Nevertheless, the complexity of living things allow exceptions. Occasionally a pathogen or innocuous microbes concealed in animals or found in the environment can jump to a human causing diseases.

An illness acquired from an animal is referred to as a zoonotic disease or a zoonosis. Sometimes, the zoonosis turns out be contagious. Almost all calamitous epidemics and pandemics have arisen from accidental transfer of a bacteria or a virus from an animal species to humans and subsequent evolution- their origin is zoonotic. Ebola, Severe Acute Respiratory Syndrome, Middle East Respiratory Syndrome and COVID-19 are zoonotic diseases. The zoonotic infections such as plague, smallpox, measles and swine flu caused first magnitude pandemics in the past.

 

Ebola Virus Disease: near pandemic situation 2014-2016

A previously unknown sickness broke out near the Ebola River in Congo in 1976, killing almost 80% of persons who contracted it. The cause of the disease, subsequently named Ebola, was found to be a virus endemically associated with bats. Although the virus does no harm to the bats, when transferred to humans via contact during hunting, a fatal condition, similar to a flu occurs. The exposure to body fluids of the infected persons passes the disease to the community. The Ebola outbreak 2014-2016, spread across West Africa. Some cases were also reported in Europe and the United States.

 

Severe Acute Respiratory Syndrome (SARS) and Middle East Respiratory Syndrome (MERS): The older cousins of COVID-19

Coronaviruses with crown like spikes on the surface exist everywhere. Until early 2000s, they were not considered a threat to humans. In 2002, a new contagious respiratory disease, SARS, emerged in China and spread rapidly to several other countries. International corporation; coordinated by WHO quickly elucidated the nature of the condition. The cause of the disease was identified to be a virus harboured by some bats, transferred to humans by palm civets. Handling civet cat meat in wet markets is believed to have caused the transmission of the pathogen to humans. The epidemic was effectively controlled by isolation of infected persons, use of masks, protective equipment, physical distancing and thermal sensing of passengers in airports. In July 2003, WHO declared SARS had been contained.

Another respiratory viral disease MERS first reported in Saudi Arabia in 2012 crossed continents due to air travel. The second major MERS outbreak occurred in South Korea in 2015. Compared to SARS, MERS is more virulent but less contagious, and spreads through close contacts of infected persons. The origin of MERS virus is zoonotic, bats being the primary source and camels the intermediate which transferred the pathogen to humans. The virus may have undergone genetic change in camels facilitating its adaptation to humans.

 

How pandemics evolve

Pandemics and epidemics begin when an infectious agent enters a community possessing no immunity to resist. A tragic example is measles epidemic in Fiji. In 1875, an Australian delegation carried the virus to the island whose natives were never exposed to the measles – a disease quite common in Asia and Europe. In a matter of months 30 percent of the population died!

Zoonotic viruses are particularly dangerous because humans are not exposed to them at the beginning. The absence of immunity allowed an epidemic in one locality to expand as a pandemic. Furthermore, when a virus originally found in an animal, genetically and associatively distant from humans, is harboured in an intermediate host closer to humans, some genetic intermingling could occur via processes referred to as recombination and re-assortment. This way, the virus acquires a foreignness needed to evade the human immune response and a kinship favourable for adaptation. Domesticated animals sometimes carry viruses originally derived from humans but genetically modified. A virus found in a wild animal co-infecting a domesticated one can copy genetic information from the latter producing a new kind of virus, adaptable to humans and also withstand host immunity.

The origin of the virus causing COVID-19 named SARS-Cov-2 has been traced to a bat species. The genetic make-up of SARS-Cov-2 tally nearly 95 percent with a virus found in so-called horseshoe bats. It is not conclusive whether the virus passed directly from a bat to humans or through an intermediate host. There exists no evidence to support the conspiracy theories that the virus leaked from a laboratory. Finding out how the virus came into being would shed light on how to control it effectively.

Once a pathogen enters a population devoid of immunity, the number of infected people begins to expand exponentially at a rate proportional to the population density reaching a peak. Thereafter, because of the decrease of susceptible persons owing to acquisition of immunity and deaths, the disease wanes.

Mathematical models predict above behaviour and point to the important concept of the effective reproduction number of a progressing epidemic. Effective reproduction number (RE) is the average number of people who acquire the infection from one infected individual at a given time. The idea of reproduction number was first introduced by the British Physician Ronald Ross, who took up mathematics to find a way to eradicate malaria. Ross showed that in order to control an epidemic RE needed to be kept below one. His suggestions for doing this paved the way for the eradication of malaria epidemics in Sri Lanka. In the initial phases of the COVID-19 pandemic in Wuhan, China RE has been in the range 3-5. Control measures such as physical distancing, wearing masks and isolation reduce RE, but the issue is reducing the number further to reach values below one. The mode of evolution of the COVID-19 pandemic is complicated by human migration by imposition and withdrawal of preventive measures.

Transmissibility and virulence

The virus is not after vengeance to be noxiously virulent and kill as many as possible; evolution in that direction renders no advantage because if a large majority of infected persons die, the virus will be deprived of hosts to feed on and reproduce.

The probability that someone will catch the infection from an infected person depends on the rate and quantity of the pathogen transmitted. A severe infection produces larger progeny of viruses; this has some advantage to the virus. Generally, pathogens compromise between transmissibility and virulence giving a higher weightage to the former. The transmissibility of COVID-19 is high because the infected shred the virus before symptoms fully develop. Contrastingly, in case of SARS; the infected release the pathogen at later stages when symptoms are readily identifiable enabling isolation; this is the main reason why SARS was contained and the COVID-19 transmission continues.

The virus aggressively attacking elderly and sparing younger could also be an advantage to the virus. Severely sick elderly patients release larger quantities of virus, infecting the younger who take care of them. The younger move about and infect others. The virus wants to procreate and exploits everything possible for that purpose!

Variations of the virus

Zoonotic viruses undergo major genetic changes via recombination or re-assortment and adapt to human system. Mutations enable them to fine-tune the traits favourable for adaptation by small genetic adjustments. When viruses replicate, their genetic code is sometimes copied erroneously, resulting in random variations. The process is analogous to typographical errors you make when you retype your essay. Even if you retype thousand times, you would not expect to find an improved version of the essay as result of random typographical errors. However, when a virus replicate trillions of times; a more adaptable one may originate and replicate endlessly – these are new strains of the virus. Recently, more contagious strains have been found to proliferate in the UK, Brazil and South Africa. The British Prime Minister announced that the variant identified in his country seemed to be more virulent.

Convergent evolution of strains

The three strains of the virus (United Kingdom, Brazil and South Africa) seemed to have evolved independently. Yet, all the three variants have undergone similar changes in the spike protein, enabling the virus to attach to host cells more strongly; this is essential for efficient spreading. The qualities acquired indicate that mutations have got selected for the definite purpose of convergence to the same cause – to spread the disease fast.

Convergent evolution is quite common in nature. A prototypical example is the near identical streamlined body shapes of the shark and the dolphin. Shark is classified as a primitive fish, whereas the dolphin has been an evolutionarily modern four-legged mammal that lived on land adapted to the ocean. Both shark and dolphin independently evolved towards the optimum hydrodynamic body features to be able to swim fast.

Future of the Present Pandemic and Future Pandemics

It is too early to determine the degree of effectiveness of existing vaccines to new and emerging strains. Fortunately, some vaccines can be easily reprogrammed to provide immunity to new strains. The world will soon acquire the arsenal of weapons needed to fight it. Efficacious vaccines have been demonstrated, and many are in the pipeline. Antiviral drug research progresses although to date there exist no cure for COVID-19. The virtues of physical distancing, wearing masks, contact tracing and isolation are gaining acceptance. Hopefully wide vaccinations programmes and strict adherence to preventive measures will help subdue the pandemic; a concerted effort is imperative. As pointed out in the editorial The Island editorial of 21st January 2021 ensuring equitable access to vaccines is an urgency. This the factor determining what lies ahead and how the pandemic will halt.

Doing the needful forthwith is prudent because given sufficient time the virus might mutate in response to a single political decision implemented somewhere, irrespective of the geographical location.

The other issue would be the emergence of new pandemics in the future – most likely those of zoonotic origin. During the past two decades many such diseases have surfaced. Excessive interference with environment; clearing forests, maintaining millions of farm animals in unnatural conditions and climate change resulting from burning fossil fuels probably contribute this dangerous trend.

When humankind turns cruel to animals, destroy flora and engender environment, the return could be a pandemic!

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Features

Islamophobia and the threat to democratic development

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There’s an ill more dangerous and pervasive than the Coronavirus that’s currently sweeping Sri Lanka. That is the fear to express one’s convictions. Across the public sector of the country in particular many persons holding high office are stringently regulating and controlling the voices of their consciences and this bodes ill for all and the country.

The corrupting impact of fear was discussed in this column a couple of weeks ago when dealing with the military coup in Myanmar. It stands to the enduring credit of ousted Myanmarese Head of Government Aung San Suu Kyi that she, perhaps for the first time in the history of modern political thought, singled out fear, and not power, as the principal cause of corruption within the individual; powerful or otherwise.

To be sure, power corrupts but the corrupting impact of fear is graver and more devastating. For instance, the fear in a person holding ministerial office or in a senior public sector official, that he would lose position and power as a result of speaking out his convictions and sincere beliefs on matters of the first importance, would lead to a country’s ills going unaddressed and uncorrected.

Besides, the individual concerned would be devaluing himself in the eyes of all irrevocably and revealing himself to be a person who would be willing to compromise his moral integrity for petty worldly gain or a ‘mess of pottage’. This happens all the while in Lankan public life. Some of those who have wielded and are wielding immense power in Sri Lanka leave very much to be desired from these standards.

It could be said that fear has prevented Sri Lanka from growing in every vital respect over the decades and has earned for itself the notoriety of being a directionless country.

All these ills and more are contained in the current controversy in Sri Lanka over the disposal of the bodies of Covid victims, for example. The Sri Lankan polity has no choice but to abide by scientific advice on this question. Since authorities of the standing of even the WHO have declared that the burial of the bodies of those dying of Covid could not prove to be injurious to the wider public, the Sri Lankan health authorities could go ahead and sanction the burying of the bodies concerned. What’s preventing the local authorities from taking this course since they claim to be on the side of science? Who or what are they fearing? This is the issue that’s crying out to be probed and answered.

Considering the need for absolute truthfulness and honesty on the part of all relevant persons and quarters in matters such as these, the latter have no choice but to resign from their positions if they are prevented from following the dictates of their consciences. If they are firmly convinced that burials could bring no harm, they are obliged to take up the position that burials should be allowed.

If any ‘higher authority’ is preventing them from allowing burials, our ministers and officials are conscience-bound to renounce their positions in protest, rather than behave compromisingly and engage in ‘double think’ and ‘double talk’. By adopting the latter course they are helping none but keeping the country in a state of chronic uncertainty, which is a handy recipe for social instabiliy and division.

In the Sri Lankan context, the failure on the part of the quarters that matter to follow scientific advice on the burials question could result in the aggravation of Islamophobia, or hatred of the practitioners of Islam, in the country. Sri Lanka could do without this latter phobia and hatred on account of its implications for national stability and development. The 30 year war against separatist forces was all about the prevention by military means of ‘nation-breaking’. The disastrous results for Sri Lanka from this war are continuing to weigh it down and are part of the international offensive against Sri Lanka in the UNHCR.

However, Islamophobia is an almost world wide phenomenon. It was greatly strengthened during Donald Trump’s presidential tenure in the US. While in office Trump resorted to the divisive ruling strategy of quite a few populist authoritarian rulers of the South. Essentially, the manoeuvre is to divide and rule by pandering to the racial prejudices of majority communities.

It has happened continually in Sri Lanka. In the initial post-independence years and for several decades after, it was a case of some populist politicians of the South whipping-up anti-Tamil sentiments. Some Tamil politicians did likewise in respect of the majority community. No doubt, both such quarters have done Sri Lanka immeasurable harm. By failing to follow scientific advice on the burial question and by not doing what is right, Sri Lanka’s current authorities are opening themselves to the charge that they are pandering to religious extremists among the majority community.

The murderous, destructive course of action adopted by some extremist sections among Muslim communities world wide, including of course Sri Lanka, has not earned the condemnation it deserves from moderate Muslims who make-up the preponderant majority in the Muslim community. It is up to moderate opinion in the latter collectivity to come out more strongly and persuasively against religious extremists in their midst. It will prove to have a cementing and unifying impact among communities.

It is not sufficiently appreciated by governments in the global South in particular that by voicing for religious and racial unity and by working consistently towards it, they would be strengthening democratic development, which is an essential condition for a country’s growth in all senses.

A ‘divided house’ is doomed to fall; this is the lesson of history. ‘National security’ cannot be had without human security and peaceful living among communities is central to the latter. There cannot be any ‘double talk’ or ‘politically correct’ opinions on this question. Truth and falsehood are the only valid categories of thought and speech.

Those in authority everywhere claiming to be democratic need to adopt a scientific outlook on this issue as well. Studies conducted on plural societies in South Asia, for example, reveal that the promotion of friendly, cordial ties among communities invariably brings about healing among estranged groups and produces social peace. This is the truth that is waiting to be acted upon.

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Pakistan’s love of Sri Lanka

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By Sanjeewa Jayaweera

It was on 3rd January 1972 that our family arrived in Karachi from Moscow. Our departure from Moscow had been delayed for a few weeks due to the military confrontation between Pakistan and India. It ended on 16th December 1971. After that, international flights were not permitted for some time.

The contrast between Moscow and Karachi was unbelievable. First and foremost, Moscow’s temperature was near minus 40 degrees centigrade, while in Karachi, it was sunny and a warm 28 degrees centigrade. However, what struck us most was the extreme warmth with which the airport authorities greeted our family. As my father was a diplomat, we were quickly ushered to the airport’s VIP Lounge. We were in transit on our way to Rawalpindi, the airport serving the capital of Islamabad.

We quickly realized that the word “we are from Sri Lanka” opened all doors just as saying “open sesame” gained entry to Aladdin’s cave! The broad smile, extreme courtesy, and genuine warmth we received from the Pakistani people were unbelievable.

This was all to do with Mrs Sirima Bandaranaike’s decision to allow Pakistani aircraft to land in Colombo to refuel on the way to Dhaka in East Pakistan during the military confrontation between Pakistan and India. It was a brave decision by Mrs Bandaranaike (Mrs B), and the successive governments and Sri Lanka people are still enjoying the fruits of it. Pakistan has been a steadfast and loyal supporter of our country. They have come to our assistance time and again in times of great need when many have turned their back on us. They have indeed been an “all-weather” friend of our country.

Getting back to 1972, I was an early beneficiary of Pakistani people’s love for Sri Lankans. I failed the entrance exam to gain entry to the only English medium school in Islamabad! However, when I met the Principal, along with my father, he said, “Sanjeewa, although you failed the entrance exam, I will this time make an exception as Sri Lankans are our dear friends.” After that, the joke around the family dinner table was that I owed my education in Pakistan to Mrs B!

At school, my brother and I were extended a warm welcome and always greeted “our good friends from Sri Lanka.” I felt when playing cricket for our college; our runs were cheered more loudly than of others.

One particular incident that I remember well was when the Embassy received a telex from the Foreign inistry. It requested that our High Commissioner seek an immediate meeting with the Prime Minister of Pakistan, Mr Zulifikar Ali Bhutto (ZB), and convey a message from Mrs B. The message requested that an urgent shipment of rice be dispatched to Sri Lanka as there would be an imminent rice shortage. As the Ambassador was not in the station, the responsibility devolved on my father.

It usually takes about a week or more to get an audience with the Prime Minister (PM) of a foreign country due to their busy schedule. However, given the urgency, my father spoke to the Foreign Ministry’s Permanent Sectary, who fortunately was our neighbour and sought an urgent appointment. My father received a call from the PM’s secretary around 10 P.M asking him to come over to the PM’s residence. My father met ZB around midnight. ZB was about to retire to bed and, as such, was in his pyjamas and gown enjoying a cigar! He had greeted my father and had asked, “Mr Jayaweera, what can we do for great friend Madam Bandaranaike?. My father conveyed the message from Colombo and quietly mentioned that there would be riots in the country if there is no rice!

ZB had immediately got the Food Commissioner of Pakistan on the line and said, “I want a shipload of rice to be in Colombo within the next 72 hours!” The Food Commissioner reverted within a few minutes, saying that nothing was available and the last export shipment had left the port only a few hours ago to another country. ZB had instructed to turn the ship around and send it to Colombo. This despite protests from the Food Commissioner about terms and conditions of the Letter of Credit prohibiting non-delivery. Sri Lanka got its delivery of rice!

The next was the visit of Mrs B to Pakistan. On arrival in Rawalpindi airport, she was given a hero’s welcome, which Pakistan had previously only offered to President Gaddafi of Libya, who financially backed Pakistan with his oil money. That day, I missed school and accompanied my parents to the airport. On our way, we witnessed thousands of people had gathered by the roadside to welcome Mrs B.

When we walked to the airport’s tarmac, thousands of people were standing in temporary stands waving Sri Lanka and Pakistan flags and chanting “Sri Lanka Pakistan Zindabad.” The noise emanating from the crowd was as loud and passionate as the cheering that the Pakistani cricket team received during a test match. It was electric!

I believe she was only the second head of state given the privilege of addressing both assemblies of Parliament. The other being Gaddafi. There was genuine affection from Mrs B amongst the people of Pakistan.

I always remember the indefatigable efforts of Mr Abdul Haffez Kardar, a cabinet minister and the President of the Pakistan Cricket Board. From around 1973 onwards, he passionately championed Sri Lanka’s cause to be admitted as a full member of the International Cricket Council (ICC) and granted test status. Every year, he would propose at the ICC’s annual meeting, but England and Australia’s veto kept us out until 1981.

I always felt that our Cricket Board made a mistake by not inviting Pakistan to play our inaugural test match. We should have appreciated Mr Kardar and Pakistan’s efforts. In 1974 the Pakistan board invited our team for a tour involving three test matches and a few first-class games. Most of those who played in our first test match was part of that tour, and no doubt gained significant exposure playing against a highly talented Pakistani team.

Several Pakistani greats were part of the Pakistan and India team that played a match soon after the Central Bank bomb in Colombo to prove that it was safe to play cricket in Colombo. It was a magnificent gesture by both Pakistan and India. Our greatest cricket triumph was in Pakistan when we won the World Cup in 1996. I am sure the players and those who watched the match on TV will remember the passionate support our team received that night from the Pakistani crowd. It was like playing at home!

I also recall reading about how the Pakistani government air freighted several Multi Barrell artillery guns and ammunition to Sri Lanka when the A rmy camp in Jaffna was under severe threat from the LTTE. This was even more important than the shipload of rice that ZB sent. This was crucial as most other countries refused to sell arms to our country during the war.

Time and again, Pakistan has steadfastly supported our country’s cause at the UNHCR. No doubt this year, too, their diplomats will work tirelessly to assist our country.

We extend a warm welcome to Mr Imran Khan, the Prime Minister of Pakistan. He is a truly inspirational individual who was undoubtedly an excellent cricketer. Since retirement from cricket, he has decided to get involved in politics, and after several years of patiently building up his support base, he won the last parliamentary elections. I hope that just as much as he galvanized Sri Lankan cricketers, his political journey would act as a catalyst for people like Kumar Sangakkara and Mahela Jayawardene to get involved in politics. Cricket has been called a “gentleman’s game.” Whilst politics is far from it!.

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Covid-19 health rules disregarded at entertainment venues?

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Believe me, seeing certain videos, on social media, depicting action, on the dance floor, at some of these entertainment venues, got me wondering whether this Coronavirus pandemic is REAL!

To those having a good time, at these particular venues, and, I guess, the management, as well, what the world is experiencing now doesn’t seem to be their concerned.

Obviously, such irresponsible behaviour could create more problems for those who are battling to halt the spread of Covid-19, and the new viriant of Covid, in our part of the world.

The videos, on display, on social media, show certain venues, packed to capacity – with hardly anyone wearing a mask, and social distancing…only a dream..

How can one think of social distancing while gyrating, on a dance floor, that is over crowded!

If this trend continues, it wouldn’t be a surprise if Coronavirus makes its presence felt…at such venues.

And, then, what happens to the entertainment scene, and those involved in this field, especially the musicians? No work, whatsoever!

Lots of countries have closed nightclubs, and venues, where people gather, in order to curtail the spread of this deadly virus that has already claimed the lives of thousands.

Thailand did it and the country is still having lots of restrictions, where entertainment is concerned, and that is probably the reason why Thailand has been able to control the spread of the Coronavirus.

With a population of over 69 million, they have had (so far), a little over 25,000 cases, and 83 deaths, while we, with a population of around 21 million, have over 80,000 cases, and more than 450 deaths.

I’m not saying we should do away with entertainment – totally – but we need to follow a format, connected with the ‘new normal,’ where masks and social distancing are mandatory requirements at these venues. And, dancing, I believe, should be banned, at least temporarily, as one can’t maintain the required social distance, while on the dance floor, especially after drinks.

Police spokesman DIG Ajith Rohana keeps emphasising, on TV, radio, and in the newspapers, the need to adhere to the health regulations, now in force, and that those who fail to do so would be penalised.

He has also stated that plainclothes officers would move around to apprehend such offenders.

Perhaps, he should instruct his officers to pay surprise visits to some of these entertainment venues.

He would certainly have more than a bus load of offenders to be whisked off for PCR/Rapid Antigen tests!

I need to quote what Dr. H.T. Wickremasinghe said in his article, published in The Island of Tuesday, February 16th, 2021:

“…let me conclude, while emphasising the need to continue our general public health measures, such as wearing masks, social distancing, and avoiding crowded gatherings, to reduce the risk of contact with an infected person.

“There is no science to beat common sense.”

But…do some of our folks have this thing called COMMON SENSE!

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