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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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US’ drastic aid cut to UN poses moral challenge to world

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An UN humanitarian mission in the Gaza. [File: Ashraf Amra/Anadolu Agency]

‘Adapt, shrink or die’ – thus runs the warning issued by the Trump administration to UN humanitarian agencies with brute insensitivity in the wake of its recent decision to drastically reduce to $2bn its humanitarian aid to the UN system. This is a substantial climb down from the $17bn the US usually provided to the UN for its humanitarian operations.

Considering that the US has hitherto been the UN’s biggest aid provider, it need hardly be said that the US decision would pose a daunting challenge to the UN’s humanitarian operations around the world. This would indeed mean that, among other things, people living in poverty and stifling material hardships, in particularly the Southern hemisphere, could dramatically increase. Coming on top of the US decision to bring to an end USAID operations, the poor of the world could be said to have been left to their devices as a consequence of these morally insensitive policy rethinks of the Trump administration.

Earlier, the UN had warned that it would be compelled to reduce its aid programs in the face of ‘the deepest funding cuts ever.’ In fact the UN is on record as requesting the world for $23bn for its 2026 aid operations.

If this UN appeal happens to go unheeded, the possibilities are that the UN would not be in a position to uphold the status it has hitherto held as the world’s foremost humanitarian aid provider. It would not be incorrect to state that a substantial part of the rationale for the UN’s existence could come in for questioning if its humanitarian identity is thus eroded.

Inherent in these developments is a challenge for those sections of the international community that wish to stand up and be counted as humanists and the ‘Conscience of the World.’ A responsibility is cast on them to not only keep the UN system going but to also ensure its increased efficiency as a humanitarian aid provider to particularly the poorest of the poor.

It is unfortunate that the US is increasingly opting for a position of international isolation. Such a policy position was adopted by it in the decades leading to World War Two and the consequences for the world as a result for this policy posture were most disquieting. For instance, it opened the door to the flourishing of dictatorial regimes in the West, such as that led by Adolph Hitler in Germany, which nearly paved the way for the subjugation of a good part of Europe by the Nazis.

If the US had not intervened militarily in the war on the side of the Allies, the West would have faced the distressing prospect of coming under the sway of the Nazis and as a result earned indefinite political and military repression. By entering World War Two the US helped to ward off these bleak outcomes and indeed helped the major democracies of Western Europe to hold their own and thrive against fascism and dictatorial rule.

Republican administrations in the US in particular have not proved the greatest defenders of democratic rule the world over, but by helping to keep the international power balance in favour of democracy and fundamental human rights they could keep under a tight leash fascism and linked anti-democratic forces even in contemporary times. Russia’s invasion and continued occupation of parts of Ukraine reminds us starkly that the democracy versus fascism battle is far from over.

Right now, the US needs to remain on the side of the rest of the West very firmly, lest fascism enjoys another unfettered lease of life through the absence of countervailing and substantial military and political power.

However, by reducing its financial support for the UN and backing away from sustaining its humanitarian programs the world over the US could be laying the ground work for an aggravation of poverty in the South in particular and its accompaniments, such as, political repression, runaway social discontent and anarchy.

What should not go unnoticed by the US is the fact that peace and social stability in the South and the flourishing of the same conditions in the global North are symbiotically linked, although not so apparent at first blush. For instance, if illegal migration from the South to the US is a major problem for the US today, it is because poor countries are not receiving development assistance from the UN system to the required degree. Such deprivation on the part of the South leads to aggravating social discontent in the latter and consequences such as illegal migratory movements from South to North.

Accordingly, it will be in the North’s best interests to ensure that the South is not deprived of sustained development assistance since the latter is an essential condition for social contentment and stable governance, which factors in turn would guard against the emergence of phenomena such as illegal migration.

Meanwhile, democratic sections of the rest of the world in particular need to consider it a matter of conscience to ensure the sustenance and flourishing of the UN system. To be sure, the UN system is considerably flawed but at present it could be called the most equitable and fair among international development organizations and the most far-flung one. Without it world poverty would have proved unmanageable along with the ills that come along with it.

Dehumanizing poverty is an indictment on humanity. It stands to reason that the world community should rally round the UN and ensure its survival lest the abomination which is poverty flourishes. In this undertaking the world needs to stand united. Ambiguities on this score could be self-defeating for the world community.

For example, all groupings of countries that could demonstrate economic muscle need to figure prominently in this initiative. One such grouping is BRICS. Inasmuch as the US and the West should shrug aside Realpolitik considerations in this enterprise, the same goes for organizations such as BRICS.

The arrival at the above international consensus would be greatly facilitated by stepped up dialogue among states on the continued importance of the UN system. Fresh efforts to speed-up UN reform would prove major catalysts in bringing about these positive changes as well. Also requiring to be shunned is the blind pursuit of narrow national interests.

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Egg white scene …

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Hi! Great to be back after my Christmas break.

Thought of starting this week with egg white.

Yes, eggs are brimming with nutrients beneficial for your overall health and wellness, but did you know that eggs, especially the whites, are excellent for your complexion?

OK, if you have no idea about how to use egg whites for your face, read on.

Egg White, Lemon, Honey:

Separate the yolk from the egg white and add about a teaspoon of freshly squeezed lemon juice and about one and a half teaspoons of organic honey. Whisk all the ingredients together until they are mixed well.

Apply this mixture to your face and allow it to rest for about 15 minutes before cleansing your face with a gentle face wash.

Don’t forget to apply your favourite moisturiser, after using this face mask, to help seal in all the goodness.

Egg White, Avocado:

In a clean mixing bowl, start by mashing the avocado, until it turns into a soft, lump-free paste, and then add the whites of one egg, a teaspoon of yoghurt and mix everything together until it looks like a creamy paste.

Apply this mixture all over your face and neck area, and leave it on for about 20 to 30 minutes before washing it off with cold water and a gentle face wash.

Egg White, Cucumber, Yoghurt:

In a bowl, add one egg white, one teaspoon each of yoghurt, fresh cucumber juice and organic honey. Mix all the ingredients together until it forms a thick paste.

Apply this paste all over your face and neck area and leave it on for at least 20 minutes and then gently rinse off this face mask with lukewarm water and immediately follow it up with a gentle and nourishing moisturiser.

Egg White, Aloe Vera, Castor Oil:

To the egg white, add about a teaspoon each of aloe vera gel and castor oil and then mix all the ingredients together and apply it all over your face and neck area in a thin, even layer.

Leave it on for about 20 minutes and wash it off with a gentle face wash and some cold water. Follow it up with your favourite moisturiser.

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Confusion cropping up with Ne-Yo in the spotlight

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Ne-Yo: His management should clarify the last-minute cancellation

Superlatives galore were used, especially on social media, to highlight R&B singer Ne-Yo’s trip to Sri Lanka: Global superstar Ne-Yo to perform live in Colombo this December; Ne-Yo concert puts Sri Lanka back on the global entertainment map; A global music sensation is coming to Sri Lanka … and there were lots more!

At an official press conference, held at a five-star venue, in Colombo, it was indicated that the gathering marked a defining moment for Sri Lanka’s entertainment industry as international R&B powerhouse and three-time Grammy Award winner Ne-Yo prepares to take the stage in Colombo this December.

What’s more, the occasion was graced by the presence of Sunil Kumara Gamage, Minister of Sports & Youth Affairs of Sri Lanka, and Professor Ruwan Ranasinghe, Deputy Minister of Tourism, alongside distinguished dignitaries, sponsors, and members of the media.

Shah Rukh Khan: Disappointed his fans in Sri Lanka

According to reports, the concert had received the official endorsement of the Sri Lanka Tourism Promotion Bureau, recognising it as a flagship initiative in developing the country’s concert economy by attracting fans, and media, from all over South Asia.

Nick Carter: His concert, too, was cancelled due to “Unforeseen circumstances

However, I had that strange feeling that this concert would not become a reality, keeping in mind what happened to Nick Carter’s Colombo concert – cancelled at the very last moment.

Carter issued a video message announcing he had to return to the USA due to “unforeseen circumstances” and a “family emergency”.

Though “unforeseen circumstances” was the official reason provided by Carter and the local organisers, there was speculation that low ticket sales may also have been a factor in the cancellation.

Well, “Unforeseen Circumstances” has cropped up again!

In a brief statement, via social media, the organisers of the Ne-Yo concert said the decision was taken due to “unforeseen circumstances and factors beyond their control.”

Ne-Yo, too, subsequently made an announcement, citing “Unforeseen circumstances.”

The public has a right to know what these “unforeseen circumstances” are, and who is to be blamed – the organisers or Ne-Yo!

Ne-Yo’s management certainly need to come out with the truth.

However, those who are aware of some of the happenings in the setup here put it down to poor ticket sales, mentioning that the tickets for the concert, and a meet-and-greet event, were exorbitantly high, considering that Ne-Yo is not a current mega star.

We also had a cancellation coming our way from Shah Rukh Khan, who was scheduled to visit Sri Lanka for the City of Dreams resort launch, and then this was received: “Unfortunately due to unforeseen personal reasons beyond his control, Mr. Khan is no longer able to attend.”

Referring to this kind of mess up, a leading showbiz personality said that it will only make people reluctant to buy their tickets, online.

“Tickets will go mostly at the gate and it will be very bad for the industry,” he added.

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