Features
Re-infections with Covid-19:
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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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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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!.
Author
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!
