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Africa: How Worried Should You Be About Coronavirus Variants? A Virologist Explains His Concerns - AllAfrica - Top Africa News
Analysis - Spring has sprung, and there is a sense of relief in the air. After one year of lockdowns and social distancing, more than 171 million COVID-19 vaccine doses have been administered in the U.S. and about 19.4% of the population is fully vaccinated. …
United States — Spring has sprung, and there is a sense of relief in the air. After one year of lockdowns and social distancing, more than 171 million COVID-19 vaccine doses have been administered in the U.S. and about 19.4% of the population is fully vaccinated. But there is something else in the air: ominous SARS-CoV-2 variants. I am a virologist and vaccinologist, which means that I spend my days studying viruses and designing and testing vaccine strategies against viral diseases. In the case of SARS-CoV-2, this work has taken on greater urgency. We humans are in a race to become immune against this cagey virus, whose ability to mutate and adapt seems to be a step ahead of our capacity to gain herd immunity. Because of the variants that are emerging, it could be a race to the wire. Five variants to watch RNA viruses like SARS-CoV-2 constantly mutate as they make more copies of themselves. Most of these mutations end up being disadvantageous to the virus and therefore disappear through natural selection. Occasionally, though, they offer a benefit to the mutated or so-called genetic-variant virus. An example would be a mutation that improves the ability of the virus to attach more tightly to human cells, thus enhancing viral replication. Another would be a mutation that allows the virus to spread more easily from person to person, thus increasing transmissibility. None of this is surprising for a virus that is a fresh arrival in the human population and still adapting to humans as hosts. While viruses don't think, they are governed by the same evolutionary drive that all organisms are - their first order of business is to perpetuate themselves. These mutations have resulted in several new SARS-CoV-2 variants, leading to outbreak clusters, and in some cases, global spread. They are broadly classified as variants of interest, concern or high consequence. Currently there are five variants of concern circulating in the U.S.: the B.1.1.7, which originated in the U.K.; the B.1.351., of South African origin; the P.1., first seen in Brazil; and the B.1.427 and B.1.429, both originating in California. Each of these variants has a number of mutations, and some of these are key mutations in critical regions of the viral genome. Because the spike protein is required for the virus to attach to human cells, it carries a number of these key mutations. In addition, antibodies that neutralize the virus typically bind to the spike protein, thus making the spike sequence or protein a key component of COVID-19 vaccines. India and California have recently detected "double mutant" variants that, although not yet classified, have gained international interest. They have one key mutation in the spike protein similar to one found in the Brazilian and South African variants, and another already found in the B.1.427 and B.1.429 California variants. As of today, no variant has been classified as of high consequence, although the concern is that this could change as new variants emerge and we learn more about the variants already circulating. More transmission and worse disease These variants are worrisome for several reasons. First, the SARS-CoV-2 variants of concern generally spread from person to person at least 20% to 50% more easily. This allows them to infect more people and to spread more quickly and widely, eventually becoming the predominant strain. For example, the B.1.1.7 U.K. variant that was first detected in the U.S. in December 2020 is now the prevalent circulating strain in the U.S., accounting for an estimated 27.2% of all cases by mid-March. Likewise, the P.1 variant first detected in travelers from Brazil in January is now wreaking havoc in Brazil, where it is causing a collapse of the health care system and led to at least 60,000 deaths in the month of March. Second, SARS-CoV-2 variants of concern can also lead to more severe disease and increased hospitalizations and deaths. In other words, they may have enhanced virulence. Indeed, a recent study in England suggests that the B.1.1.7 variant causes more severe illness and mortality. Another concern is that these new variants can escape the immunity elicited by natural infection or our current vaccination efforts. For example, antibodies from people who recovered after infection or who have received a vaccine may not be able to bind as efficiently to a new variant virus, resulting in reduced neutralization of that variant virus. This could lead to reinfections and lower the effectiveness of current monoclonal antibody treatments and vaccines. Researchers are intensely investigating whether there will be reduced vaccine efficacy against these variants. While most vaccines seem to remain effective against the U.K. variant, one recent study showed that the AstraZeneca vaccine lacks efficacy in preventing mild to moderate COVID-19 due to the B.1.351 South African variant. On the other hand, Pfizer recently announced data from a subset of volunteers in South Africa that supports high efficacy of its mRNA vaccine against the B.1.351 variant. Other encouraging news is that T-cell immune responses elicited by natural SARS-CoV-2 infection or mRNA vaccination recognize all three U.K., South Africa, and Brazil variants. This suggests that even with reduced neutralizing antibody activity, T-cell responses stimulated by vaccination or natural infection will provide a degree of protection against such variants. Stay vigilant, and get vaccinated What does this all mean? While current vaccines may not prevent mild symptomatic COVID-19 caused by these variants, they will likely prevent moderate and severe disease, and in particular hospitalizations and deaths. That is the good news. Sign up for free AllAfrica Newsletters Get the latest in African news delivered straight to your inbox Success! Almost finished... We need to confirm your email address. To complete the process, please follow the instructions in the email we just sent you. Error! There was a problem processing your submission. Please try again later. However, it is imperative to assume that current SARS-CoV-2 variants will likely continue to evolve and adapt. In a recent survey of 77 epidemiologists from 28 countries, the majority believed that within a year current vaccines could need to be updated to better handle new variants, and that low vaccine coverage will likely facilitate the emergence of such variants. What do we need to do? We need to keep doing what we have been doing: using masks, avoiding poorly ventilated areas, and practicing social distancing techniques to slow transmission and avert further waves driven by these new variants. We also need to vaccinate as many people in as many places and as soon as possible to reduce the number of cases and the likelihood for the virus to generate new variants and escape mutants. And for that, it is vital that public health officials, governments and nongovernmental organizations address vaccine hesitancy and equity both locally and globally. [Insight, in your inbox each day. You can get it with The Conversation's email newsletter.] Paulo Verardi, Associate Professor of Virology and Vaccinology, University of Connecticut This article is republished from The Conversation Africa under a Creative Commons license. Read the original article.
Africa: We've Discovered a New Rule of Nature. It Explains Why Animals' Pointy Parts Grow the Way They Do - AllAfrica - Top Africa News
Analysis - Discoveries of new overarching rules or "laws" in nature are very rare.
Discoveries of new overarching rules or "laws" in nature are very rare. Surprisingly, my colleagues and I have found a new rule of biological growth that explains unexpected similarities in sharp structures found across the tree of life -- in teeth, horns, claws, beaks, animal shells, and even the thorns and prickles of plants. The discovery could help us look forward in evolution to predict how animals, including humans, and their many parts are likely to evolve. Our findings are published today in the open access journal BMC Biology. The power of laws Some patterns are very common in nature, such as logarithmic spirals that follow the golden ratio. These patterns appear because of the very simple processes that generate them. For example, a logarithmic spiral is produced when a spiral grows faster on one side than the other. We can describe such patterns as following rules of growth. These rules help us understand why animals and plants are the shapes they are. In my research I am fascinated by patterns in nature. And for many years I have searched for a pattern in how teeth grow. By looking at hundreds of teeth and measuring how they get wider as they get longer, my team and I identified a simple mathematical formula that underpins tooth shape. This is a "power law", in which there's a straight-line relationship between a tooth's width and length when you take a logarithm of these measurements. Power laws are also found in the sizes of earthquakes, extinction rates of animals and movements of the stock market. Thorns, horns and hooves We named the new power law the "power cascade", as it describes how the surface of a tooth cascades down while following a specific pattern. We looked at teeth from huge sharks, Tyrannosaurus rex, mammoths and humans, and saw the power cascade pattern in all of them. Amazingly, the rule also works for claws, hooves, horns, spider fangs, snail shells, antlers, and the beaks of mammals, birds and dinosaurs. We even observed it in the horns of a Triceratops skeleton to be displayed at Melbourne Museum. Perhaps these structures have a common shape because many of them carry out the same job. For instance, a sharp dinosaur tooth is useful for puncturing the flesh of prey, as is a sharp claw. Nonetheless, we still find the power cascade pattern in physical traits that aren't for piercing and have different shapes overall, such as shells and backward-facing horns. Is it really a law of nature? While I first noticed the power cascade about ten years ago using a technique I'd developed to measure 3D shapes, the long road to its discovery began much earlier. The pattern builds on an idea first put forward in 1659 by Sir Christopher Wren, a polymath anatomist, physicist, mathematician and the architect of St Paul's Cathedral in London. Wren considered a snail shell may be a cone twisted around a logarithmic spiral. We now know shells and other shapes such as teeth and horns follow the power cascade shape, called a "power cone". The power cascade then seems to be the missing piece of a 350-year-old puzzle of how animals grow. But despite how common it is, can we really deem it a "law" of nature? It was reasonably common for previous generations of biologists to refer to strong patterns (including the logarithmic spiral) as biological laws. Biologists these days are very hesitant to use this term as it implies an unbreakable rule, such as the law of gravity. However, we can show there are very simple processes of growth which produce the power cascade pattern. Therefore, when animals and plants grow in this way they will inevitably produce the power cascade shape, just as is the case with logarithmic spirals. Certainly this rule can be bent, as seen by grooved snake fangs. But given the immense variety of animal parts it works for and the many shapes it makes, there's a strong case to be made for classifying it as a power law of nature. Future research will be able to confirm this. Predicting evolution (and life-like dragons) What can we do with this newly discovered rule? Well, to start it can help us think about the likely course of evolution. Sign up for free AllAfrica Newsletters Get the latest in African news delivered straight to your inbox Success! Almost finished... We need to confirm your email address. To complete the process, please follow the instructions in the email we just sent you. Error! There was a problem processing your submission. Please try again later. The evolution of animals is usually thought to include a lot of "random" factors. This makes it difficult to know exactly what animals will end up looking like many millennia from now. That said, the power cascade is perhaps the simplest way for a pointed structure to form when an animal is growing as an embryo or juvenile. Thus, we'd expect this shape to be very common both now and in the future -- and we know the former to be true. We can even apply the power cascade to imagine what shapes the teeth, horns and claws of mythical creatures might look like if they followed rules in nature. In other words, we can now design dragons in Game of Thrones and fantastic beasts in Harry Potter to look as realistic as possible. Moreover, many structures such as horns have evolved independently in different animals. So each time this happens in the future, it will probably follow the power cascade shape. Humans with horns remain may an unlikely reality, but at least we'll know what this would look like. Alistair Evans, Associate Professor, Monash University This article is republished from The Conversation Africa under a Creative Commons license. Read the original article.
WHO to Probe Flu-Like Illness in Those Vaccinated for Covid-19 - AllAfrica.com
The Global Advisory Committee on Vaccine Safety Covid-19 Subcommittee has met virtually to review available information and data on reports of influenza-like illness in health-care workers who had received Covid-19 vaccines. These symptoms have been reported …
The Global Advisory Committee on Vaccine Safety Covid-19 Subcommittee has met virtually to review available information and data on reports of influenza-like illness in health-care workers who had received Covid-19 vaccines. These symptoms have been reported in several countries. Based on a careful scientific review of the information made available, the Subcommittee came to the following conclusions: Symptoms of an influenza-like illness may be expected as immune responses following vaccinations in general. The current reports with the COVID-19 vaccines are consistent with the expected side-effect profile of these vaccines, all of which were well tolerated. In view of this, the committee considers that the benefit-risk balance of the COVID-19 vaccines (for which reports of the influenza-like reactions are available to date) remains favourable and does not suggest any revision, at present, to the recommendations around the safety of these vaccines.
Africa: When Covid Becomes a Bad Cold - Experts Map the Future of SARS-CoV-2 - AllAfrica.com
Analysis - Scientists predict the virus will be with us for the long run, but probably as just another common cold.
Scientists predict the virus will be with us for the long run, but probably as just another common cold. In the early days of the Covid-19 pandemic, many doctors, researchers, journalists and public health officials spent considerable energy describing how the SARS-CoV-2 virus was not "just another flu" but something far more deadly and debilitating. Now, with at least three effective vaccines being rolled out overseas and local vaccination programmes an ever-closer prospect, scientists are turning their attention to the long-term prospects of Covid-19. In a 5 January commentary published in Nature Reviews Immunology, Marc Veldhoen of the University of Lisbon and J Pedro Simas of the Catholic University of Portugal draw on recent data that show that antibodies in people who have been infected by SARS-CoV-2, as well as those who have been vaccinated against it, persist for more than six months. After that people become increasingly vulnerable to reinfection. Veldhoen and Simas argue that the behaviour of the virus and the body's immune response is closely aligned to other coronaviruses. There are already four coronaviruses circulating through the human population that cause common colds, mild upper respiratory tract infections that are seldom fatal. At any time, 60% to... Read the full story on Daily Maverick.
South Africa: Will Vaccines Eradicate SARS-CoV-2? - AllAfrica - Top Africa News
In the early days of the Covid-19 pandemic, many doctors, researchers, journalists and public health officials spent considerable energy describing how the SARS-CoV-2 virus was not "just another flu" but something far more deadly and debilitating.
In the early days of the Covid-19 pandemic, many doctors, researchers, journalists and public health officials spent considerable energy describing how the SARS-CoV-2 virus was not "just another flu" but something far more deadly and debilitating. Now, with at least three effective vaccines being rolled-out overseas and local vaccination programmes an ever-closer prospect, scientists are turning their attention to the long-term prospects of Covid-19. In a 5 January commentary published in Nature Reviews Immunology, Marc Veldhoen of the University of Lisbon and J. Pedro Simas of the Catholic University of Portugal draw on recent data that shows that antibodies in people who have been infected by SARS-CoV-2, as well as those who have been vaccinated against SARS-CoV-2, persist for over six months. After that people become increasingly vulnerable to reinfection. Veldhoen and Simas argue that the behaviour of the virus and the body's immune response is closely aligned to other coronaviruses. There are already four coronaviruses circulating through the human population that cause common colds, mild upper respiratory tract infections that are seldom fatal. At any time, 60-70% of the population have antibodies that fight these viruses - what Veldhoen and Simas call a spectrum of immunity. Over time, smaller groups of people are intermittently reinfected (this is what characterises virus as endemic). The high rates of immunity mean that the group as a whole is protected, and the risk of severe infection in vulnerable people is much lower. With there being a time limit on the protection afforded by infection or vaccination, Veldhoen and Simas argue that global vaccination programmes will not succeed in totally eradicating Covid-19. Sign up for free AllAfrica Newsletters Get the latest in African news delivered straight to your inbox Success! Almost finished... We need to confirm your email address. To complete the process, please follow the instructions in the email we just sent you. Error! There was a problem processing your submission. Please try again later. But there is good news. They predict that vaccination programmes will not need to continue in perpetuity, as long as a high percentage of people who possess antibodies to the virus is maintained. This will limit the spread of future outbreaks. In short, Veldhoen and Simas predict that SARS-CoV-2 is likely to become a "fifth endemic common cold [corona]virus". Veldhoen and Simas argue that the emergence of Covid-19 variants will not have a significant effect on population immunity as "new variants will unlikely differ sufficiently to escape established immunity." Nature journals are the most reputable in the scientific community but Veldhoen and Simas's commentary must be treated cautiously as predicting the future is hard. Nevertheless, the bottom line is this: Vaccinations are important. We will probably not eradicate SARS-CoV-2 but the death rate from the disease will come right down to similar low levels associated with the common cold. GroundUp is being sued after we exposed dodgy Lottery deals involving millions of rands. Please help fund our defence. You can support us via Givengain, Snapscan, EFT, PayPal or PayFast. Read the original article on GroundUp.
South Africa: Covid-19 - Millions of Injection Devices Will Be Needed for Vaccines - AllAfrica - Top Africa News
The delivery of a safe and effective COVID-19 vaccine once it becomes available in South Africa will be a complex and costly logistical exercise.
The delivery of a safe and effective COVID-19 vaccine once it becomes available in South Africa will be a complex and costly logistical exercise. Vials with vaccine are of no use unless they are administered to people using injection devices such as syringes and needles. Acquiring enough of these devices is part of crucial logistical planning to ensure rapid, equitable access to COVID-19 vaccines. Next steps for COVID-19 vaccines in SA South Africa, through the World Health Organization-led COVAX facility, has made a commitment to secure 5.7 million doses, to cover at least 10 percent of the population, at a cost of more than R2 billion. The Solidarity Fund, on behalf of South Africa, is scheduled to make the first down payment of more than R327 000 by 15 December. The Department of Health envisages a vaccine will become available by mid-2021. Before it can be marketed in South Africa, a COVID-19 vaccine will have to be registered or authorised by the South African Health Products Regulatory Authority (SAHPRA). Spotlight previously reported on how SAHPRA might go about authorising COVID-19 vaccines. The country's immunisation programme, which is mainly geared towards children, will need to scale up to cope with the demand of rolling out a COVID-19 vaccine to include adults. It is not yet clear what the plans are for this scale-up. The WHO has outlined distribution steps countries will have to plan for before vaccines become available. These include training healthcare workers, identification and up-scaling of immunisation sites such as clinics, hospitals and pharmacies. Refrigeration to keep the vaccine at optimal temperatures is also essential so that vaccines can be stored and transported to centres including rural areas without breaking the cold chain and degrading the efficacy of the vaccine. Security will also need to be beefed up to prevent theft of the products for sale on the illegal market. Competition for injection devices Ian Wakefield, the Africa general manager for Becton Dickinson (BD), a global medical technology company, predicts a surge in demand for injection devices. "As we saw in the early days of the pandemic with tests and Personal Protective Equipment such as masks, South Africa is likely to be caught up in a worldwide competition for essential vaccination equipment," he says. BD, a producer of vaccine injection devices, claims they manufacture 12-billion syringe units annually. Of these, three billion are for vaccines. "In light of the COVID-19 pandemic, we [are] in the process of ramping up supply with an additional one billion units, which equates to manufacturing 2 000 injection devices every minute," says Wakefield. About 800 million injection units have already been committed to Canada, the United Kingdom and the United States and Saudi Arabia are finalising their order, he says. The South African Department of Health has not yet entered into formal talks with BD on injection device procurement, says Wakefield. The medical technology company currently supplies syringes for the BCG vaccine (a childhood TB vaccine) in all the provinces at a tender price of around R1.55 a unit. Wakefield understands that access to a COVID-19 vaccine is currently at the top of the health department's list of priorities for the pandemic. However, he says planning for delivery cannot be ignored. "We would like discussions with health ministries in Africa because globally, the first movers, US and UK, have bought ahead of time. There is going to be a limited supply of syringes to deliver on all these vaccines. We want to raise awareness that vaccine delivery includes delivery (from the vial to the person being vaccinated). It's key that governments look at this now before it's too late. Because when the actual vaccine is here and there is no planning we are going to be behind the curve." The quantity of devices that will be needed for South Africa, he says, is not yet clear and will depend on the vaccine chosen for delivery. Some vaccines, including the Moderna and Pfizer vaccine, which have been approved for use in the United Kingdom and Canada and are scheduled to be approved in the United States soon, require two doses. "An amount of 10 million doses will be needed for 5 million people, which means millions of injection devices will be needed to meet the threshold for herd immunity." Wakefield cannot say much about exact costs of a BD injection device. "Since pricing is of a competitive nature we are not able to provide exact pricing for our vaccine delivery devices in South Africa and other markets. However, BD supplies vaccine delivery devices to UNICEF for low- and middle-income countries at market access prices," he says. Sign up for free AllAfrica Newsletters Get the latest in African news delivered straight to your inbox Success! Almost finished... We need to confirm your email address. To complete the process, please follow the instructions in the email we just sent you. Error! There was a problem processing your submission. Please try again later. 'Hundreds of suppliers' Professor Greg Hussey, a member of the Ministerial Advisory Committee on vaccines and the Director of Vaccines for Africa, agrees millions of injection devices will be needed by mid-2021. "It is an issue, but it's not a tool that needs to be specialised for a COVID-19 vaccine and there are hundreds of suppliers globally. The main concern is the distribution and storage of the vaccine and the monitoring and evaluation system of the vaccine's effectiveness once it is rolled out," he says. "Delivery of a vaccine is a challenge, and it virtually doubles the cost of acquiring a vaccine. Apart from devices, we are going to have to ensure that enough masks are available for healthcare workers as well as people who come for the vaccine," says Hussey. *Adele Baleta is an independent science Writer, WHO vaccine safety communications advisor and Internews pandemic advisor. Read the original article on spotlight.