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Even if you’ve been vaccinated, it’s important to keep masking up

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Can you spread COVID-19 after vaccination? Here’s what we know

by Kate Baggaley

December 28, 2020

On December 18, the U.S. Food and Drug Administration granted Moderna’s COVID-19 vaccine emergency use authorization. The vaccine is the second to win approval in the US, and the first doses were administered on Monday.

This milestone is impressive both because the vaccines from Moderna and Pfizer were developed at record-breaking speed and because they appear to be more than 90 percent effective (at least in clinical trials) at protecting people from developing symptomatic COVID-19. But one thing that isn’t clear yet is whether COVID-19 vaccines will also prevent vaccinated people from carrying the novel coronavirus without feeling sick and unwittingly spreading it to others. This means that for now, it’s important to keep wearing masks, socially distancing, and taking other precautionary measures even if you have been vaccinated.

“It would not be so far-fetched to have a vaccine that protects you from developing the worst COVID disease, but you could be infected and you could be spreading it [without] getting really sick,” says Jeffrey Bethony, a professor of microbiology, immunology, and tropical medicine at the George Washington University School of Medicine and Health Sciences who works on vaccines for parasitic diseases and HIV. “There is hope that they prevent transmission, but we simply don’t know enough about them yet.”

One reason that this novel virus—officially called SARS-CoV-2—has spread so rampantly is that people can be contagious several days before they feel ill, and in some cases never develop symptoms. Such a high rate of asymptomatic spread is “just not all that common in other infections,” says Susanna Naggie, an associate professor of medicine in the Duke University School of Medicine who specializes in infectious diseases. “With flu there is asymptomatic disease, but not at the level we see with SARS-CoV-2.” This makes it particularly important to understand whether COVID-19 vaccines will prevent asymptomatic infections, she says.

Many vaccines—including those for hepatitis A and B, measles, chickenpox, and human papillomavirus—do prevent people both from becoming ill and from passing the pathogen to others. “Generally, we believe that if you have a vaccine that prevents disease, you’re likely preventing infections as well, but you can’t assume that that’s 100 percent [the case],” Naggie says.

Some pathogens can infect and reproduce in vaccinated people for short periods of time without making them sick, including the bacteria that cause meningitis and pertussis, or whooping cough. This is also a problem for vaccines under development for parasitic illnesses such as malaria, schistosomiasis, and hookworm infection, Bethony says. “The vaccine protects people against the most serious clinical manifestations of the disease but it doesn’t entirely stop infection,” Bethony says. “You still might have a person who is mildly infected, and they’re still able to spread the disease.”

Whether an inoculation will prevent infection partly depends on the vaccine’s mechanism of action. Many COVID-19 vaccines, including those by Moderna and Pfizer, target the spike-shaped proteins on the surface of SARS-CoV-2 that help it bind to and enter host cells. “We’re talking about developing antibodies and immune response directly to the spike protein,” Naggie says. “So the hope would be that you could truly prevent infection.”

Several developers have reported early data hinting that their COVID-19 vaccines will reduce asymptomatic infections. During late-stage trials for the vaccine developed by the University of Oxford and AstraZeneca, some participants were given weekly COVID-19 tests. One group accidentally was given a low first dose of the vaccine followed by the intended full second dose. Asymptomatic infections were less common in this vaccinated group than they were among those who received a placebo. Researchers are still investigating why that low-dose group fared better than the full-dose group in that regard.

In Moderna’s clinical trials, researchers swabbed participants before they received each of their two doses of the vaccine. On December 15, the drugmaker reported that 38 volunteers who received the placebo tested positive without showing COVID-19 symptoms before their second dose, compared with only 14 from the group that received the vaccine.

“Presumably that means it also decreases the risk of transmission, although to prove that will take a lot more work,” Naggie says. “Maybe the vaccine completely prevents infection, or maybe it really shortens the period of infection and someone sheds for only a couple of days … these would all be very critical pieces to answer that.”

Investigating this question may become easier as at-home COVID-19 testing kits become more common. In follow-up clinical trials, researchers could ask people to swab themselves daily and track how often vaccinated people test positive and whether they pass the virus to other members of their household, Naggie says.

Several vaccine developers, including Moderna and Pfizer, are planning to test the blood of trial participants for antibodies that recognize a part of the virus that wasn’t targeted by the vaccine. Such antibodies would indicate whether a person became infected after being vaccinated.

Another way to find out how well COVID-19 vaccines prevent transmission is to monitor areas where vaccination is prevalent to see if infections also drop among the remaining unvaccinated people, Bethony says. This type of situation occurred after the first polio vaccine was introduced in 1955; the following year, scientists saw fewer cases even than they were expecting because enough kids had been immunized that the virus had trouble reaching those who hadn’t.

In the US, COVID-19 vaccines have only become available within the past several weeks and aren’t expected to be distributed to the general public before next spring. It’s going to be a while before we reach herd immunity. It’s also still unclear what percent of Americans need to be vaccinated for us to reach this stage as herd immunity depends on many factors including how quickly the virus spreads within various communities, and how effective the vaccines are at preventing the spread of the novel virus.

“We are just getting access to the vaccine and so for some months to come … we probably are still looking at questions about the role of the vaccine in transmission and the need to continue all these public health measures,” Naggie says. “For the time being, until we have adequate immunity in our communities and until we know better about transmission, the answer is yes.” So get vaccinated when you are able and keep masking up.

 

(POPULAR SCIENCE)



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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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Health services face imminent collapse due to fuel crisis

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A file picture of a recent doctors’ protest

By Dr B. J. C. PERERA

MBBS(Cey), DCH(Cey), DCH(Eng), MD(Paed), MRCP(UK), FRCP(Edin), FRCP(Lon), FRCPCH(UK), FSLCPaed, FCCP, Hony FRCPCH(UK), Hony. FCGP(SL)

Specialist Consultant Pediatrician and Honorary Senior Fellow, Postgraduate Institute of Medicine, University of Colombo, Sri Lanka.

Our free National Health Service is something that brings succor to the poorest of the poor, as well as even the well-to-do, and everybody in-between. As a country and a nation, we are so proud of our health services. In fact, as a developing country, we have shown the entire world how much can be accomplished, even with our meager resources, and with so few facilities made available to us in our health facilities. Our healthcare personnel are second to none anywhere else on the planet, and they try to do their best, even under trying circumstances.

There are shortages of medicines, disposable articles and equipment in our healthcare institutions. It has really gotten worse during the current economic crisis. Yet, we have managed to rise above all that, innovate, beg, borrow and do our best for the patients who come to us. Generally, our health workers will not allow a life to be lost without a fight. A case in point is how these personnel, from the lowest-ranked to the highest, rose and fought tooth and nail during the current COVID-19 pandemic. They worked without any worthwhile rest, even foregoing their meals when things had to be done to save lives. Our countrymen and countrywomen hailed us as their saviours, singing hosannas to all of them for so selflessly handling the crisis. The healthcare personnel showed results and they sacrificed many things and went through hell on earth, to save lives.

However, there is a looming dragon that is likely to inflict telling blows to cripple this hallowed service that is provided for our people. It is not due to shortages of drugs or equipment. Those can be handled to the very best of our abilities. The problem is due to severe human resource depletion that is the likely result of the current fuel shortage. It is a looming catastrophe, as large as life, where our healthcare personnel will not be able to get to their places of work, and they will not be able to respond to sudden emergencies, as there is no transport. The government, ministers and all other stupid politicians do not seem to realise this, and perhaps could not even care less about that. That is of course to be expected, as they have their agendas. They will somehow get their things done, but the people who suffer would be the poor who come to our hospitals.

However, the most distressing thing about this entire fiasco is how among our general public, the thugs, ruffians, desperados, those engaged in nefarious hoarding of fuel and all kinds of Mafias, are beginning to treat healthcare personnel at fuel queues and fuel sheds. Healthcare personnel are not asking for special treatment at fuel stations. They are an absolutely essential service, and all they are asking is for some fuel to enable them to attend to their essential service provisions. Even ambulances have to wait in queues, and are not allowed by the irate public to get priority for fuel.

A couple of weeks ago we saw in the news that a lady doctor driver was driven away from a fuel station by a mob. The most distressing thing about that entire episode was the bravado of a non-health staff lady driver, who shouted with powerful gesticulation of her arms that she had children in the car and could not make concessions to lady doctors. God forbid, but what if one of those children suddenly fell ill and the person to attend to them was the very same lady doctor who was chased away, and that person was not able to get to the hospital due to the lack of fuel?

Starting from Friday the 24th of June 2022, there was a lukewarm arrangement made to provide fuel to essential services, from certain designated fuel stations. every Friday. This was not communicated properly through all the media, and in very many places the public vehemently objected to this. The Borella junction Ceypetco fuel shed was one of the stations which were allocated for this purpose, where the essential services people, including healthcare personnel, queued up in their vehicles from around 6.00 am. The bowsers of fuel arrived only in the late evening, after a 12-hour long wait. There was hardly any security cover and virtually a free for all, with the sparse security personnel turning a blind eye to all the misdemeanors of the general public. There were loads of nurses, doctors and other healthcare workers from the National Hospital, Lady Ridgeway Hospital for Children, National Eye Hospital, De Soysa Maternity Hospital and the Castle Street Hospital for Women, who were in these vehicle queues, twiddling their thumbs and being forced to keep away from their places of work. No doubt, these hospitals worked with only minimal skeleton staff. All these hospitals have a collective staff strength running into very large numbers, all working in an absolutely vital essential service. In some outstation areas, the incensed public insisted on the healthcare personnel queuing up with the general public, even on that dedicated Friday, and at least in one area, the hospital had to be closed as most of the hospital staff had to be in fuel queues. For whatever it is worth, this writer has not been able to see his patients for more than a week due to lack of fuel.

Unless a proper system to provide fuel to essential services is implemented by this impotent government, this situation will go from bad to worse. Many hospitals will have to be closed, not due to strikes or trade union actions, but due to a lack of human resources to run the hospitals. Medical personnel will not be able to attend to emergencies, especially outside working hours, and many lives will be lost. Our inability to provide timely treatment could also lead to some patients being maimed for life.

So be warned, our people of our own country. Selfishness and scant regard for law and order on the part of the general public will lead to an unprecedented catastrophe. There will be riots inside and outside the medical institutions with damage to public property. Innocent lives will be lost and blood will necessarily have to be on the hands of the decision-makers and the powers-that-be.

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