COVID-19 Pandemic End?

COVID-19 Pandemic End?


Wouldn’t it be so nice to wake up one morning and see the pandemic gone, totally banished from the face of the Earth? This may not happen anytime soon: in some countries, like India and Brazil, the deadly COVID-19 saga has turned into a prolonged nightmare from which millions are yet to wake up.

And COVID is real. What’s unreal today are expectations of the so-called “herd immunity” kicking in at some vague time in the near future. That future is not guaranteed for the world, as ramped-up vaccinations are only happening in rich countries, and "vaccine nationalism” remains high. Besides, the required level immunity to achieve “herd immunity” to COVID remains unknown at this point — is it really just 60%, 80% or even higher?

It has been thought that, at some point, the pandemic will be over. And the world will then go “back to normal.” This thinking, however, is flawed.Some experts say the coronavirus — like the viruses behind polio, measles and the fly — is likely to be a “permanent” one. Meaning, it’s not going away. One scenario is that it may turn into a seasonal flu, less deadly, but would still claim some lives.

And like the flu virus, which still mutates with every season, the coronavirus has demonstrated that — given its known mutations — the virus is able to mount a cat-and-mouse game with vaccines.

Given this scenario, it’s hard to imagine now how our lives may ever go back to “normal”, according to some experts. Here’s what we know so far:

Indian scientists tracking the coronavirus recently found something interesting —a "double mutant" COVID-19 variant. It was at the Center For Cellular & Microbiology, in Hyderabad, where this particular strain was first sequenced.

The variant was initially detected in Maharashtra's Nagpur district in December last year. Recently, other cases were also reported from Delhi, Gujarat and Punjab, among others. It has now reportedly spread to 18 states in the subcontinent.

Dr Rakesh Mishra, the centre’s director, explained it is the result of the E484Q and L452R strains coming together to form a third strain. The L452R strain was first reported in California and the E484Q is an “indigenous” strain found in India. There's no name/code assigned to it yet.

On Wednesday (March 24, 2021), scientists under the Indian SARS-CoV-2 Consortium on Genomics (INSACOG) confirmed an “increase in the fraction of samples with the E484Q and L425R mutations” compared with December last year.

Since its founding in December 2020, the consortium has been carryring out genomic sequencing and analyses of COVID-19 variants circulating in India. INSACOG groups 10 labs in the country and correlates their findings with data on genomic mutations gathered in a common global scientific database. Viral genome sequences on GISAID come from different corners of the planet, uploaded at a rate of about 5,000 per day.

Dr Mishra told Indian media the new strain is “efficient”... but “not yet a superspreader”. And there’s is no reason to believe that it is more deadly — just yet. He stressed, however, that more investigation is needed to fully understand it, as well as future mutations of the SARS-CoV-2 in the country.

At the moment, there is no evidence to show that vaccines in India — Covishield and Covaxin — will not work against these new strains, according to him. So far, there's been no link between the double mutant virus with the surge in COVID-19 cases in several states, according to INSACOG.

Viral mutation is a natural phenomenon. They mutate all the time. As a virus it keeps changing in small ways. Most of the time, such minute changes don’t matter, if they don’t change how the virus behaves in general. Single mutations may occur in a part of the virus RNA that causes a change in a particular building block. There could also be many mutations — that eventually alter an entire viral RNA.

While tens of thousands of minor SARS-CoV-2 mutations had been seen by scientists, rare block-altering mutations can trigger changes in its viral structure. For example, they could confer greater efficiency in the spike protein, bumping up its ability to hijack human cells. Such variants could potentially be more infectious and cause more severe disease.

When enough mutations happen in a viral family tree (or a lineage), the virus can begin to function differently. That lineage can be classified as a so-called “variant of concern”. That’s why constant global surveillance is necessary, and global leaders have called for a new pandemic treaty to boost surveillance and coordinated action.

1. Using open-access scientific databases like GISAID, researchers from around the world are able to track viral mutations by comparing and contrastring them.

2. These shared databases would help determine whether the "double mutant" is the same lineage as the one found in the UK, or whether this combination of mutations independently emerged, as was the case for the K417N/T, E484K, and N501Y trio of mutations that came together in Brazil and South Africa to give rise to their strains, P.1 and B.1.351.

Since it was first sequenced in early January 2020, SARS-CoV-2 has been mutating. Researchers have catalogued more than 12,000 mutations in SARS-CoV-2 genomes, according to a Nature article published in September 2020. Scientists say the virus's mutation rate is actually “sluggish”.

On March 3, 2021, a group led by Dr Rui Wang, a mathematician at Michigan State University, analysed 45,494 complete SARS-CoV-2 genome sequences gathered from different parts of the the world to understand mutations (12,754 sequences came from the US).

“Our analysis suggests the presence of four sub-strains and 11 top mutations in the US,” Wang wrote in the open-access "Communications Biology” journal. “These 11 top mutations belong to 3 disconnected groups. The first and second groups consisting of 5 and 8 concurrent mutations are prevailing, while the other group with three concurrent mutations gradually fades out.”

Researchers also found that female immune systems are more active than those of males in responding to SARS-CoV-2 infections. “One of the top mutations, 27964C > T-(S24L) on ORF8, has an unusually strong gender dependence.” More importantly, Wang’s group uncovered that two of four SARS-CoV-2 sub-strains in the US were “potentially more infectious.”

The B.1.1.7 variant — first discovered by researchers in Britain in November 2020 — till now has been the most aggressively transmissible one among the many variants. For example, as cases rise in the US, at least 40 states in US have recorded cases that contracted COVID-19 with the B.1.1.7 variant, according to Dr Wang.

“Coronavirus is here with us. We’re not going to be able to eradicate it. It seems very unlikely,” said Gypsyamber D’Souza, professor of epidemiology at Johns Hopkins Bloomberg School of Public Health (JHSPH), said on April 6, 2021.

One example is the infection that caused the “Cocoliztli Epidemic”, a form of viral haemorrhagic fever that killed 15 million inhabitants of Mexico and Central America from 1545 to 1548. “Cocoliztli" is the Aztec word for "pest." A recent study that examined DNA from the skeletons of victims found that they were infected with a subspecies of Salmonella known as S. paratyphi C, which causes enteric fever, a category of fever that includes typhoid. Enteric fever can cause high fever, dehydration and gastrointestinal problems and is still a major health threat at present.

Another example: Polio cases have decreased by over 99% since 1988, from an estimated more than 350 000 cases to 22 reported cases in 2017, according to the WHO. But the polio virus is still active, and does still exist.

Nobody knows at this point. Scientists initially said a 60% to 70% herd immunity threshold is needed to keep the coronavirus at bay. Dr D’Souza said: “For coronavirus, we think that it’s probably around 70% of people would need to have immunity before the rest of the group would be protected.”

That’s also the original figure mentioned by Dr Anthony Fauci, director of the US National Institute of Allergy and Infectious Diseases (NIAID), in December 2020. But Dr Fauci, as well as others, have bumped the number upward.

“We need to have some humility here,” Dr Fauci told Vox on December 15, 2020. “We really don’t know what the real number is. I think the real range is somewhere between 70 to 90%. But, I’m not going to say 90%.”

It’s still possible to achieve herd immunity to coronavirus, given the human experience with other pathogens. John Dowdy, JHSPH associate professor of epidemiology, said: “There are lot of examples of viruses that we have achieved some level of herd immunity to. One example, the far end of success, is smallpox, where we were able to fully eradicate the disease.”

For all the talk about vaccines, one thing is clear: It’s your own immune system that fights off pathogens, not the vaccine. A vaccine simply gives your immune system a “mugshot” of a pathogen, or disease-causing agent like SARS-CoV-2.

Dr. Jeremy Kamil, a US virologist, says it typically takes about 14-days for your body to build up a repertoire of “memory” — or “adaptive” immune cells specific for a certain virus or other pathogen. "The best vaccine is the one you’re offered first. Pretty much all of the vaccines in use can save your life from dying of COVID-19, even if you get infected by a variant."

“Immunity to the coronavirus can be achieved either through (a) natural infection or (b) through a vaccine,” Dr Dowdy said. “They don’t have to be two separate things. We can have some immunity from natural infection, and also some immunity from a vaccine.”

“In most places in the world, we think that that level of natural infection right now (as of April 6, 2021) is still only 20% or less,” said Dr Dowdy. “And so we still have a long way to go. And certainly, the fastest, and safest way, to get there is through a vaccine,” he added.

Recent developments in certain countries, specifically in Brazil, UK, South Africa, the US and India, in which the virus continues to mutate, achieving “herd immunity” may be a moonshot anytime soon, say experts.

Even the US, which leads most other countries in vaccinations and already had large outbreaks, won’t hit a herd immunity level, according to Christopher Murray at the University of Washington and Peter Piot at the London School of Hygiene and Tropical Medicine, in a New York Times report.

They doubted that the US — which today leads in vaccinations — would reach herd immunity. The main reason: the ongoing emergence of new variants that “behave almost like new viruses”.

Findings of a study published in the The Lancet Respiratory Medicine in April 2021 shows previous COVID-19 infection does not fully protect people against re-infection. While it’s true that antibodies induced by SARS-CoV-2 infection are largely protective, the study showed they do not completely protect against reinfection in young people.

A “longitudinal, prospective study” of more than 3,000 young, healthy members of the US Marines Corps conducted by researchers at the Icahn School of Medicine at Mount Sinai and the Naval Medical Research Center came up with that conclusion.

“Our findings indicate that reinfection by SARS-CoV-2 in healthy young adults is common,” says Stuart Sealfon, MD, the Sara B. and Seth M. Glickenhaus Professor of Neurology at the Icahn School of Medicine at Mount Sinai and senior author of the paper.

Another clinical trial bears this out: in South Africa, people in the “placebo” group previously infected with one strain had no immunity against its mutated descendant — and became reinfected, according to a study published by the New York Academy of Sciences in February 2, 2021. Similar reports came out of Brazil, which had seen massive outbreaks — and subsequently suffered renewed epidemics.

Given that the coronavirus is here to stay, there are two ways to achieve immunity — contract the virus naturally (and recover), or get vaccinated. Despite the rapid viral transmission of SARS-CoV-2, it is thought only 20% of the world’s population has achieved some sort of immunity through natural infection. So the remaining 80% would have to either wait to be infected naturally or get a vaccine, as the coronavirus is expected to be with us — for better or for worse.

Some of the shots available today are still effective against some of the new variants. Experts, however, believe their efficacy will wane over time against the coming mutations.

Some vaccine makers are already working on new jabs for the new mutations. This is where the advantage of new mRNA vaccines comes to the fore. Shots based on this revolutionary technology can be “refashioned” faster than vaccines developed using traditional platforms (inactivated or attenuated).

Scientists point to two possible “evolutionary paths”.

One: a virus becomes more severe but not more transmissible. It will cause more disease and death, but the growth is linear.

Two: A mutating virus becomes neither more nor less virulent, but more contagious. This will cause a spike in disease and death that are exponential rather than linear.

Certain countries or regions may win over the virus, and achieve herd immunity sooner. But at the moment, COVID-19 is still unleashing its deadly payload across the world, wreaking havoc in countries like India, Brazil and the developing world.

With the new variants, even if vaccines are eventually developed against them, the shots still need to be produced, shipped, stored, distributed and administered. There are natural limitations to this process.

The virus, by default, will still infect. It will still reproduce wherever it finds non-immune or unvaccinated bodies that will enable it to jump to the next vulnerable person. In the process of copying itself, it will make more coding “mistakes”, aka yet more variants.

Today, it’s a British, South African, Indian, US or UK variant, with some sub-variants showing up in detected in states or cities. Tomorrow, it could from another part of the map.

Most mutations are nothing to worry about, say virologists. But it’s also a fact that each fresh infection could potentially give the virus what amounts to a lottery ticket. A “win” for COVID could give it greater virulence or ability to escape vaccines, or both. The more people who are vulnerable, the more transmission, and the greater number of lottery tickets the coronavirus gets, for more “wins”.

The reason more variants are detected is because genome sequencing has become more commonplace. But advanced sequencing is almost absent in the developing world. Scientists say it’s safe to assume that the virus is already mutating fast in the many poor countries where no vaccines had been administered yet.

In April, Antonio Guterres, the UN Secretary General, said 75% of all shots had been administered in just 10 countries. In about 130 other countries, not even a single shot had been given.

To say “it’s a small world after all”, without actually doing what’s necessary to cover the entire planet against this harmful pathogen, is to live in Disneyland.

Immunisation programs have accelerated. In the UAE, the rate of vaccine distribution has reached 102.19 doses per 100 people.

As of March 15, the UK has administered 39 doses per 100 people in the total population; corresponding figures for the US States and the European Union are 33 per 100 and 12 per 100, respectively.

BioNTech said on April 29, 2021 that it expected its COVID-19 vaccine, jointly developed with Pfizer, to be available to 12 to 15-year-olds in Europe from June. The US is expected to authorise the COVID-19 vaccine for children age 12 and up by early next week.

In January, Dubai launched the Vaccine Logistics Alliance for COVID-19. The move is expected to speed up the flow of vaccines globally for 2 billion doses this year.

The world keeps getting better at responding(GulfNews)
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