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Re-infections with Covid-19:

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Are they distinct possibilities?

The headline of this article appeared with a different column yesterday due to a technical problem. We apologise to our readers for the inadvertent error – Editor

By Dr.B. J. C. Perera,Specialist Consultant Paediatrician

There has been considerable debate on whether reinfections implying repeated infections with the virus SARS-CoV-2 that causes the COVID-19 disease was occurring and whether such occurrences were even possible. A reinfection is a second, third or any subsequent infection with the same virus once a person has recovered from an initial index infection. Unscrambling of those contentions were obviously extremely important from public health as well as curative health perspectives. In the not too distant past, there were some suspicious cases of possible reinfections in other parts of the world but whether those were due to a persistence of the virus in the individual, reactivation of the same illness after some time in the person or whether these were due to new second infections could not be scientifically proven with certainty. Various types of conjectures and assumptions were quite rife in the face of the ambiguity of details on the topic of reinfections.

In the human health scenario, some viruses like measles or chicken pox viruses generate virtually life-long immunity and resistance to reinfections. Second infections with these viruses are extremely rare and are almost unheard of. In the other extreme, there are viruses like those that cause the common cold, with which reinfections are extremely common. There are examples of even certain other types of human coronaviruses that cause the common cold, with the propensity to cause multiple reinfections. From a public health perspective information regarding such immunological features of an infection are absolutely vital to facilitate the formulation and implementation of preventive measures.

Being able to say for sure that there is a reinfection by another strain of the same organism depends on how reliably one could say that it is not the same original index organism that is there in the second infection. It is not easy to detect alterations in the different strains of the same organism. However, a modern technological development has made this possible. It is a technique known as genome sequencing. Whole genome sequencing is the process of determining the complete sequence of the components of an organism’s genetic structure at a given time. This technique can be used to detect differences in the genetic make-up of different strains of the same organism. When an organism undergoes any form of mutation, the new mutant will have some differences in the genome from the original index strain.

There is now convincing evidence for at least two cases, one from Hong Kong and the other from the USA, of well-documented human reinfection with SARS-CoV-2 virus. These case reports invariably generate certain questions about how commonly reinfection may occur. The cases described here have different characteristics in terms of viral genetics, timeline of reinfection and the severity of the disease. Although we can learn quite a few things from the characteristics of these two cases, it is difficult to draw firm conclusions about the clinical and public health implications of these findings.

On August 24, researchers in Hong Kong announced the first confirmed instance of human reinfection with SARS-CoV-2. It was a 33-year-old otherwise healthy man living in Hong Kong who developed three days of respiratory symptoms and was diagnosed with COVID-19 on 26th March 2020. Following recovery, he was later PCR tested twice more for SARS-CoV-2 and both tests were negative. On 15th August 2020, he was tested for SARS-CoV-2 again as a part of re-entry screening when he returned to Hong Kong from Europe. That test result was positive. He had no symptoms at the time of the second positive result. Genome sequencing revealed that the viruses isolated in March and in August were from different genetic groups, leading the study authors to conclude that the patient had been infected twice.

In the second case, a 25-year-old otherwise healthy man living in Nevada, USA, developed a respiratory viral infection and was diagnosed with COVID-19 on 18th April 2020. The patient recovered and two PCR tests for SARS-CoV-2 performed in May were negative. Then at the end of May, the patient again developed respiratory symptoms and tested positive for SARS-CoV-2 in early June 2020. Genomic sequencing revealed that the viral isolates showed a number of genetic differences between the isolates. The authors of that report concluded that based on the degrees of genetic differences between the two isolates, these were two distinct infections.

There have also been recent news reports of one case of reinfection in Belgium and one in the Netherlands, diagnosed using genome sequencing, but the scientific details of those cases were not available at the time of writing this article.

What makes these reports of reinfection different from previous reports? There have been numerous reports of patients with possible reinfection prior to this one. In April, it was reported that hundreds of people in South Korea who had recovered from COVID-19 and were retested for SARS-CoV-2, had tested positive upon retesting. To help determine whether the patients in South Korea had indeed been reinfected and if they could transmit the virus, researchers attempted to culture SARS-CoV-2 from retest samples and traced the close contacts of those with positive retest results. The virus could not be cultured and there were no confirmed COVID-19 cases among contacts, suggesting that the detected virus was not alive. It was therefore thought that what was observed in South Korea was prolonged shedding of SARS-CoV-2, a phenomenon that is now well recognised.

The best way to establish proof of reinfection is to perform genome sequencing. The technique determines the order of chemical building blocks that comprise the genetic code of an organism. Although the genomes of different SARS-CoV-2 individual virus particles are very similar to each other and hence identified as SARS-CoV-2 and not as other viruses, some differences do occur. Those differences develop through mutations, or the substitution of one chemical building block for another, as genome copies are made. Mutations may be inherited by the next generation of virus particles, resulting in viral evolution as they accumulate over time. Genome sequencing can thus help to determine whether two populations of SARS-CoV-2 evolved separately from each other or whether one gave rise to the other. This principle can be applied to virus samples obtained from a single person at two different times.

Thousands of genome sequences of SARS-CoV-2 isolates from all over the world have been published in on-line databases. Comparison and analysis of these sequences has resulted in the characterization of several clades. A clade is a group of organisms that can be traced to a common ancestor and all common descendants. These clades of SARS-CoV-2 have geographic specificity in part because viral evolution has occurred after SARS-CoV-2 has been transported between continents. It has been found that viruses from one lineage, clade G, predominate in Europe and the United States, while clade L, the progenitor of clade G, predominates in Asia. In the case of the Hong Kong patient, genomic sequencing determined that the patient’s first infection was caused by a virus from clade V, while the second was caused by a virus from clade G. This strongly suggests that the patient was infected on two separate occasions, in different parts of the world.

Is the occurrence of reinfection surprising? The possibility of reinfection with SARS-CoV-2 has been widely argued. Several lines of evidence have been used to contend against it. Until the announcement from Hong Kong, evidence in support of reinfection had not been published. On the other hand, the occurrence of SARS-CoV2 reinfection is not surprising, based on experience with other infectious diseases. “Sterilizing immunity,” or complete protection from infection after immunologic priming by natural infection or vaccination is often an elusive target, either because short-term immunity is not fool proof or because immunity tends to wane over time. Evidence from animal studies demonstrate the possibility of SARS-CoV-2 reinfection despite immunologic priming. If reinfection is possible, why are the first cases of this are only coming up being reported now? Will there be more cases in the future? It is possible there have been other cases of reinfection that have not been detected or convincingly investigated. In essence, public health surveillance systems are not set up to identify cases of reinfection.

Based on current information, it is difficult to predict how commonly reinfection will occur, but it is useful to explore whether features of the Hong Kong and Nevada cases make those patients’ situations more or less applicable to other patients. As for timing of reinfection, it is unclear how much the time period between infections, 4.5 months in the case of the Hong Kong patient, and six weeks in the case of the Nevada patient, may have contributed to the patients’ risks for reinfection. Studies have shown that SARS-CoV-2 antibodies can decline rapidly within a few weeks or months of infection but again, the role that antibodies play in immunologic protection is unclear. It is possible these patients were poorly protected against reinfection and were reinfected as soon as they were next exposed to SARS-CoV-2. Generally speaking, immunologic protection induced by natural infection or vaccination tends to wane over time. Hence the possibility that an effective COVID-19 vaccine may need to be administered repeatedly in order to maintain sufficient immunity. It is possible that as travel restrictions ease and population movement increases, exposure to SARS-CoV-2 clades that have not been previously encountered may increase the risk of reinfection. Concerns have also been expressed as to whether immune enhancement may occur for SARS-CoV-2, and in particular, if vaccination against COVID-19 could precipitate severe disease if post-vaccination infection occurs. At this time, there is no evidence from human or animal studies that SARSCoV-2 infection can precipitate immune enhancement of the disease.

Clearly a lot more scientific information is needed before tangible conclusions can be arrived at. Our perceptions on the capabilities of this blight will change over time when more and more details and research evidence is brought to light in the course of time. However, in view of the mayhem that has so far been wreaked by the virus, time is perhaps at a premium. As time is of the essence, the onus is on dedicated researchers world-wide to unravel some of these mysteries as soon as possible.



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Features

Scarcity, prices, hoarding and queuing

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By Usvatte-aratchi

We live in a scarcity economy and will do so well into 2024, past the next Presidential elections if it comes then; it may not. (The new minister may open bets.) All economies are scarcity economies; otherwise, there would be no prices. We also live in plentiful economies; look at the streets of Tokyo, Shanghai, Singapore, Paris or San Francisco during day or night. Scarcity is a relative term, as most terms are. A scarcity economy is one where prices rise relentlessly, where cigarettes are more expensive in the evening than they were the same morning. Scarcity economies will have two or more sets of prices: one official, others in markets in varying shades of grey until black. Scarcity economies are where everyone (producers, traders, households) hoards commodities, hoards everything that can be hoarded, at reasonable cost. Scarcity economy is one where productivity is lower than it was earlier, where both labour and capital idle. Scarcity itself may push down productivity. Observe thousands of people standing in queues to buy all kinds of things whilst producing nothing. That is labour idling. Others hang on to dear life in crowded trains arriving in office late to leave early, to get to ill lit homes where to cook each evening they repeat what their ancestors did millions of years ago to light a fire. Money is one commodity that can be hoarded at little cost, if there was no inflation. The million rupees you had in your savings account in 2019 is now worth a mere 500,000, because prices have risen. That is how a government taxes you outside the law: debase the currency. In an inflation afflicted economy, hoarding money is a fool’s game.

The smart game to play is to borrow to the limit, a kind of dishoarding (- negative hoarding) money. You borrow ten million now and five years later you pay 500 million because the value of money has fallen. US dollars are scarce in this economy. It is hoarded where it can wait until its price in Sri Lanka rises. Some politicians who seem to have been schooled in corruption to perfection have them stored elsewhere, as we have learnt from revelations in the international press. Electricity is not hoarded in large quantities because it is expensive to hoard. Petrol is not hoarded very much in households because it evaporates fast and is highly flammable. That does not prevent vehicle owners from keeping their tanks full in contrast to the earlier practice when they had kept tanks half empty (full). Consequently, drivers now hoard twice as much fuel in their tanks as earlier. Until drivers feel relaxed as to when they get the next fill, there will be queues. That should also answer the conundrum of the minister for energy who daily sent out more bowser loads out than earlier, but queues did not shorten.

As an aside, it is necessary to note that the scarcity economy, which has been brought about by stupid policies 2019-2022, and massive thieving from 2005 is partly a consequence of the fall in total output (GDP) in the economy. Workers in queues do not produce. The capital they normally use in production (e.g. motor cars, machines that they would otherwise would have worked at) lie idle. Both capital and labour idle and deny their usual contribution to GDP. Agriculture, industries, wholesale and retail trade, public administration, manufacturing and construction all of which have been adversely affected in various ways contribute more than 75% of total GDP. Maha (winter crop) 2021-22, Yala (spring crop) 2022 and Maha 2022-23 and fishing are all likely to have yielded (and yield) poor harvests. Manufacturing including construction are victims of severe shortages in energy and imported inputs. Wholesale and retail trade which depend directly on imports of commodities have been hit by the sharp drop in imports. Tourism, which is more significant in providing employment and foreign exchange, collapsed dreadfully since late 2019 and has not recovered yet. About 16 percent of our labour force work in the public sector. They have failed to contribute to GDP because they did not engage in productive work due to variegated reasons. Teachers were on strike for two months in 2021. In 2022, so far government employees have worked off and on. Wages of government employees are counted as contributions to GDP, by those that make GDP estimates. However, here is an instance where labour was paid but there was no output equal to the value of those wages. Such payments are rightly counted as transfers and do not count to GDP. For these reasons estimates of GDP for 2021 must be well below the 2020 level. The 3.6 growth in official estimates is unlikely. The likely drop in 2022 will be roughly of the same magnitude as in 2021. These declines are not dissonant with misery one sees in towns and the countryside: empty supermarket shelves, scant supplies of produce in country fares, scarce fish supplies, buses idling in parks and roads empty of traffic. There have been warnings from our paediatricians as well as from international organisations of wasting and probable higher rates of child mortality. It is this sort of sharp fall in wellbeing that engenders the desperation driving young and ambitious people to obtain passports to seek a living overseas. You can see those from mezzo-America amassed on the southern border of US. Will our young men and women end up beyond the wall of China?

Of this lowered supply of goods and services, this society is expected to pay a massive accumulated foreign debt. (Remember the reparation payments in the Versailles Treaty). In real terms it will mean that we forego a part of our lower incomes. Do not miss this reality behind veils of jargon woven by financial analysts. It is not something that we have a choice about. That is where international help may kick in. Gotabaya Rajapaksa government after much senseless dilly dallying has started negotiations with the IMF. There is nobody compelling our government to seek support from IMF. They are free go elsewhere as some who recently were in their government still urge. Examine alternatives and hit upon an arrangement not because it permits the family grows richer but because it will make life for the average person a little less unbearable.

If prices are expected to rise people will seek resources to hoard: money to buy commodities, space and facilities to hoard, security services to protect the property and much more. Rice producers cannot hoard their product because animals large as elephants and small as rodents eat them up. Because of the unequal distribution of resources to hoard, the poor cannot hoard. In a scarcity economy, the poor cannot hoard and famines usually victimise the poor, first and most. If prices are expected to fall, stocks are dishoarded to the market and prices fall faster and deeper. In either direction, the rate at which prices change and the height/depth of the rise/fall depends on the speed at which expectations of change in prices take place. A largescale rice miller claims he can control the price of rice at a level that the government cannot. His success/failure will tell us the extent of his monopoly power.

When commodities are scarce, in the absence of a sensible system of coupons to regulate the distribution, consumers will form queues. A queue is rarely a straight here, nor a dog’s tail (queue, in French, is a dog’s tail which most often crooked). Assembled consumers stagnate, make puddles and sometimes spread out like the Ganges, with Meghna, disgorges itself to the Bay of Bengal. They sometimes swirl and make whirlpools and then there is trouble, occasionally serious. There is order in a queue that people make automatically. To break that order is somehow iniquitous in the human mind. That is why breaking the order in a queue is enraging. For a queue to be disobeyed by anyone is infuriating, and for a politician to do so now in this country is dangerously injurious to his physical wellbeing.

The first cause of rising prices, hoarding and queues is the scarcity of goods and services in relation to the income and savings in the hands of the people.

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Terror figuring increasingly in Russian invasion of Ukraine

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In yet another mind-numbing manifestation of the sheer savagery marking the Russian invasion of Ukraine, a shopping mall in Ukraine’s eastern city of Kremenchuk was razed to the ground recently in a Russian missile strike. Reportedly more than a hundred civilian lives were lost in the chilling attack.

If the unconscionable killing of civilians is a definition of terrorism, then the above attack is unalloyed terrorism and should be forthrightly condemned by all sections that consider themselves civilized. Will these sections condemn this most recent instance of blood-curdling barbarism by the Putin regime in the Ukrainian theatre and thereby provide proof that the collective moral conscience of the world continues to tick? Could progressive opinion be reassured on this score without further delay or prevarication?

These issues need to be addressed with the utmost urgency by the world community. May be, the UN General Assembly could meet in emergency session for the purpose and speak out loud and clear in one voice against such wanton brutality by the Putin regime which seems to be spilling the blood of Ukrainian civilians as a matter of habit. The majority of UNGA members did well to condemn the Russian invasion of Ukraine close on the heels of it occurring a few months back but the Putin regime seems to be continuing the civilian bloodletting in Ukraine with a degree of impunity that signals to the international community that the latter could no longer remain passive in the face of the aggravating tragedy in Ukraine.

The deafening silence, on this question, on the part of those sections the world over that very rightly condemn terror, from whichever quarter it may emanate, is itself most intriguing. There cannot be double standards on this problem. If the claiming of the lives of civilians by militant organizations fighting governments is terror, so are the Putin regime’s targeted actions in Ukraine which result in the wanton spilling of civilian blood. The international community needs to break free of its inner paralysis.

While most Western democracies are bound to decry the Russian-inspired atrocities in Ukraine, more or less unambiguously, the same does not go for the remaining democracies of the South. Increasing economic pressures, stemming from high energy and oil prices in particular, are likely to render them tongue-tied.

Such is the case with Sri Lanka, today reduced to absolute beggary. These states could be expected ‘to look the other way’, lest they be penalized on the economic front by Russia. One wonders what those quarters in Sri Lanka that have been projecting themselves as ‘progressives’ over the years have to say to the increasing atrocities against civilians in Ukraine. Aren’t these excesses instances of state terror that call for condemnation?

However, ignoring the Putin regime’s terror acts is tantamount to condoning them. Among other things, the failure on the part of the world community to condemn the Putin government’s commissioning of war crimes sends out the message that the international community is gladly accommodative of these violations of International Law. An eventual result from such international complacency could be the further aggravation of world disorder and lawlessness.

The Putin regime’s latest civilian atrocities in Ukraine are being seen by the Western media in particular as the Russian strongman’s answer to the further closing of ranks among the G7 states to the Russian invasion of Ukraine and the issues growing out of it. There is a considerable amount of truth in this position but the brazen unleashing of civilian atrocities by the Russian state also points to mounting impatience on the part of the latter for more positive results from its invasion.

Right now, the invasion could be described as having reached a stalemate for Russia. Having been beaten back by the robust and spirited Ukrainian resistance in Kyiv, the Russian forces are directing their fire power at present on Eastern Ukraine. Their intentions have narrowed down to carving out the Donbas region from the rest of Ukraine; the aim being to establish the region as a Russian sphere of influence and buffer state against perceived NATO encirclement.

On the other hand, having failed to the break the back thus far of the Ukraine resistance the Putin regime seems to be intent on demoralizing the resistance by targeting Ukraine civilians and their cities. Right now, most of Eastern Ukraine has been reduced to rubble. The regime’s broad strategy seems to be to capture the region by bombing it out. This strategy was tried out by Western imperialist powers, such as the US and France, in South East Asia some decades back, quite unsuccessfully.

However, by targeting civilians the Putin regime seems to be also banking on the US and its allies committing what could come to be seen as indiscretions, such as, getting more fully militarily and physically involved in the conflict.

To be sure, Russia’s rulers know quite well that it cannot afford to get into a full-blown armed conflict with the West and it also knows that the West would doing its uttermost to avoid an international armed confrontation of this kind that could lead to a Third World War. Both sides could be banked on to be cautious about creating concrete conditions that could lead to another Europe-wide armed conflict, considering its wide-ranging dire consequences.

However, by grossly violating the norms and laws of war in Ukraine Russia could tempt the West into putting more and more of its financial and material resources into strengthening the military capability of the Ukraine resistance and thereby weaken its economies through excessive military expenditure.

That is, the Western military-industrial complex would be further bolstered at the expense of the relevant civilian publics, who would be deprived of much needed welfare expenditure. This is a prospect no Western government could afford to countenance at the present juncture when the West too is beginning to weaken in economic terms. Discontented publics, growing out of shrinking welfare budgets, could only aggravate the worries of Western governments.

Accordingly, Putin’s game plan could very well be to subject the West to a ‘slow death’ through his merciless onslaught on the Ukraine. At the time of writing US President Joe Biden is emphatic about the need for united and firm ‘Transatlantic’ security in the face of the Russian invasion but it is open to question whether Western military muscle could be consistently bolstered amid rising, wide-ranging economic pressures.

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At 80, now serving humanity

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Thaku Chugani! Does this name ring a bell! It should, for those who are familiar with the local music scene, decades ago.

Thaku, in fact, was involved with the original group X-Periments, as a vocalist.

No, he is not making a comeback to the music scene!

At 80, when Engelbert and Tom Jones are still active, catering to their fans, Thaku is doing it differently. He is now serving humanity.

Says Thaku: “During my tenure as Lion District Governor 2006/2007, Dr Mosun Faderin and I visited the poor of the poorest blind school in Ijebu Ode Ogun state, in Nigeria.

“During our visit, a small boy touched me and called me a white man. I was astonished! How could a blind boy know the colour of my skin? I was then informed that he is cornea blind and his vision could be restored if a cornea could be sourced for him. This was the first time in my life that I heard of a cornea transplant. “

And that incident was the beginning of Thaku’s humanity service – the search to source for corneas to restore the vision of the cornea blind.

It was in 2007, when Dr Mosun and Thaku requested Past International President Lion Rohit Mehta, who was the Chief Guest at MD 404 Nigeria Lions convention, at Illorin, in Nigeria, to assist them in sourcing for corneas as Nigeria was facing a great challenge in getting any eye donation, even though there was an established eye bank.

“We did explain our problems and reasons of not being able to harvest corneas and Lion Rohit Metha promised to look into our plea and assured us that he will try his utmost best to assist in sourcing for corneas.”

Nigeria, at that period of time, had a wait list of over 70 cornea blind children and young adults.

“As assured by PIP Lion Rohit Mehta, we got an email from Gautam Mazumdar, and Dr. Dilip Shah, of Ahmedabad, in India, inviting us for World Blind Day

“Our trip was very fruitful as it was World Blind Day and we had to speak on the blind in Nigeria.”

“We were invited by Gautam Mazumdar to visit his eye bank and he explained the whole process of eye banking.

“We requested for corneas and also informed him about our difficulties in harvesting corneas.

“After a long deliberation, he finally agreed to give us six corneas. It was a historical moment as we were going to restore vision of six cornea blind children. To me, it was a great experience as I was privileged to witness cornea transplant in my life and what a moment it was for these children, when their vision was restored.

“Thus began my journey of sight restoration of the cornea blind, and today I have sourced over 1000 corneas and restored vision of the cornea blind in Nigeria, Kenya and India till date.

“Also, I need to mention that this includes corneas to the armed forces, and their family, all over India.

“On the 12th, August, 2018, the Eye Bank, I work with, had Launched Pre-Cut Corneas, which means with one pair of eyes, donated, four Cornea Blind persons sight will be restored.”

Thaku Chugani, who is based in India, says he is now able to get corneas regularly, but, initially, had to carry them personally – facing huge costs as well as international travel difficulties, etc.

However, he says he is so happy that his humanitarian mission has been a huge success.

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