No sooner than you thought all the talk of new Covid-19 variants was over, there is news of yet another one: AY.4.2. But what is it, where did it come from and should we be concerned?
AY.4.2 is what is termed a “lineage”. These are labels given to branches of the Covid-19 evolutionary tree to illustrate their relatedness. They are overseen by the diligent Pango network, a joint team of researchers from the universities of Edinburgh and Oxford, who act as the custodians of lineages and handle the assignment of new ones.
Origins of AY.4.2
If we go back to April of this year, we can trace the origins of AY.4.2. Our team in United Kingdom’s Northumbria, working as part of Cog-UK – the British consortium that sequences the genomes of Covid-19 samples to see how the virus is changing – had just sequenced two samples connected via travel history to India.
At the time we knew the lineage circulating in India was B.1.617, but the cases we had sampled did not match this. Variants are distinguished by the different mutations they have in their genetic material and, looking at the mutations in our samples, it appeared our cases were missing some of the commonly accepted mutations of B.1.617 but also had some additional ones.
What we were reporting to colleagues in Cog-UK was classified the following week as B.1.617.2, one of three main sub-lineages of B.1.617, and which was later named Delta by the World Health Organization.
AY is a further evolutionary step forward from here. Once a lineage’s labelling gets five levels deep, a new letter combination is started to avoid the name getting too long. So the AY forms of the virus are not vastly different from what’s come before, even though their labelling is different. They are all sub-lineages of the Delta.
There are now 75 AY lineages identified, each with different additional defining mutations in their genome. One of these – AY.4 – has been steadily growing in proportion in the United Kingdom over the last few months, accounting for 63% of new UK cases in the last 28 days.
We are still not sure if AY.4’s mutations confer a genuine advantage or if the increasing frequency of the lineage is simply down to what is called a “founder effect”. This is when a subset of viruses get separated from the overall viral population, and then reproduce in isolation. In the area where the separated viruses are, all subsequent viruses will therefore be descendants of this subset.
With Covid-19, this might have happened by there being a single case at a large event. This lone virus would have been the “founder”, the only virus spreading at the event. If it infected a sizeable number of people, who later infected others, this may have quickly built up a large amount of virus all from the same origin. Sometimes, for a certain form of a virus to dominate, it does not have to be better than others – it simply needs to be in the right place at the right time.
But, given its rise to dominance in the UK, AY.4 might well have a selective advantage. The defining change in AY.4 is the mutation A1711V, which affects the virus’s Nsp3 protein, which plays a number of roles in viral replication. However, the impact of this mutation is unknown.
This brings us to AY.4.2 – a sub-lineage of AY.4 – which was first noted at the end of September, though it appears it surfaced in the UK around June. It’s defined by two additional genetic mutations, Y145H and A222V, that affect the spike protein. The spike protein is a key part of the virus’s outer surface and is the part of its structure that it uses to get inside cells.
AY.4.2 has grown steadily in volume to the point where it now accounts for about 9% of UK cases in the last 28 days. It has also been observed in a few European nations: Denmark, Germany and Ireland, to name a few.
But whether its two mutations offer the virus a selective advantage is unclear as well. A222V was previously seen last year in the B.1.177 lineage that probably emerged in Spain and was then spread across northern Europe, most likely by holidaymakers. At the time, many were sceptical that A222V conferred an advantage. Indeed, the increase in the form of the virus that’s become known as AY.4.2 seems to have only occurred since it acquired its Y145H mutation.
Effect on immunity
This mutation is within an “antigenic supersite” of the spike protein – a part of the protein that antibodies frequently recognise and target. We know that this part of the spike protein has already been modified once before by a mutation in Delta’s genetic material, and that this possibly contributes to Delta’s greater ability to escape immunity, as antibodies have a harder time targeting it as a result. However, the research exploring this is still in preprint, meaning it is yet to be formally reviewed – so we need to treat its findings with caution.
But it is, therefore, possible the Y145H mutation could give the virus an even greater ability to escape immunity by making this supersite less recognisable to antibodies.
The counterargument is that, despite introduction into several European countries, AY.4.2 has failed to take hold, dropping off the radar in Germany and Ireland – though it is lingering in Denmark. This would suggest its ability to get around immunity isn’t any greater than Delta’s. Equally, it might just be that there was not enough of AY.4.2 arriving in these places for it to take hold.
Really, it is too early to tell if this is the beginning of the next dominant lineage. Any ability it might have to escape immunity needs to be confirmed by experimental work. Clearly, though, its emergence shows that there is a continued need for genomic surveillance of the virus.
How to write an essay
Many people want to learn how to write an essay. The truth is, it is much easier than you think. There are many expert essay tutors who can assist you with your task and guide you through the process without much hassle. Here are some suggestions to help you write an essay.
Expert essay tutors can help you write and evaluate your essay. They provide high-quality unique essays and papers for students of all ages. They offer assistance with all types of written papers whether it’s an essay, a research paper, oral argument, or an essay.
Most writing tutors begin by discussing the kind of paper you are writing. This helps the tutor know the direction that the student intends on taking the assignment. For instance, if you are writing a term paper, they might discuss the topics you are considering to write about. The majority of essay writing tutors have a broad range of topics they can help with.
If you are planning to write an essay in a certain native language, for example, American English, they will be more useful. Students who are just beginning to write should consult the dictionaries and other books in their native language. These languages are not the most popular however they are used extensively. Knowing these native words will allow you to know what you’re writing about and write sentences that are punctually correct and flow smoothly.
Many people who require assistance with essay writing often have questions about the topics and subjects they’ll be writing about. Many times, they inquire about the types of reference materials or books they’ll require for their work. In other instances, they might require assistance in writing their arguments. Writing an essay requires the ability to understand and analyse information. It term paper writing help is crucial that you can convey your message clearly and concisely to ensure that your message is understood.
One of the most frequently asked questions about how to write my essay is how to format the essay. Most frequently, questions like this have a simple answer. After you’ve done your research, you can prepare your essay for submission using one of the many formats. You can first send a pdf of your essay to a school or university. The essays are typically scrutinized and reviewed by one person. If there is an error, it’s easy to fix it. You will be acknowledged as the author , and the name of the author will be displayed at the bottom of every page.
Another alternative to writing my essay is to hire an experienced writer to assist you with your essay writing service. Professional writers are familiar with the structure and formatting requirements required to write a quality written assignment. Based on the nature and complexity of your task You can seek assistance from the writer. You could also request an outline to receive an idea of the overall structure. Most writers are very willing to help novice writers at the beginning, and frequently offer suggestions on what should be included in each section. They can also provide excellent tips on how to write an impressive conclusion. Professional writers can also give suggestions on how to construct a unique structure for your essay.
The more you research your question the more likely you will be able to answer it. If you are still unsure about how to write your essay, you could engage a professional tutor or adviser to provide you guidance and write your essays for you. Many students have used the services of a personal adviser or tutor to prepare for their college applications, and you can , too. You might be anxious about beginning your academic journey as a student. However, the more you research your essay, the better you will be in navigating the course of your studies.
Know about some common types of cancer
Cancer is not just one disease. There are more than 100 types, which can start anywhere in the body. They are named by the organ or tissue in which they start growing. They can form in organs, bones, muscles, tendons, fat, blood vessels, an lymph fluid.
Examples of more common types include:
- Carcinoma- This is the most common type, which forms a solid mass of tissue (tumor). Brest, lung, an colrectal cancer are types of carcinomas.
- Leukemia– This cancer starts in the blood, occurring when large number of abnormal white blood cells build up in the blood an bone, crowding out healthy blood cells. A lack of healthy blood cells can lower one’s immune function, increasing the risk of frequent infections, fatigue, and recurrent bruising or bleeding.
- Lymphoma- this cancer arises in lymphocytes, a type of white blood cell.lymphocytes normally fight infection, but here they grow out of control. This can cause swollen lymph nodes, shortness of breath, and fatigue.
Here are some sleep hygiene tips
- Try to avoid large meals, heavy snacking, or alcohol 2-3 hours before bed.
- Ensure a comfortable temperature, as feeling too hot or cold can disrupt sleep.
- Stop using electronic devices an hour before bed, especially those emitting blue light such as smartphones, tablets, and televisions.
- If your are sensitive to caffeine, try to avoid drinking caffeinated beverages 4-6 hours before bedtime.
- Schedule before-bed activities to signal that you are winding down, such as changing into pajamas and brushing teeth.
- If you awaken and can’t return to sleep, don’t stay in bed. Get up and do quiet Relaxing activities, such as reading, until you feel tired enough to fall back asleep.
- create a quiet, dark, relaxing environment in your bedroom. Dim lights and turn off your cell phone’s sound and vibration modes if possible.
- Set a sleep schedule and stick to it. Try to go to bed at night and awaken in the morning around the same times, even on weekends. This helps to regulate the body’s sleep cycles and circadian rhythms.
Why fresh air is important for mental health ?
Know the importance of Aquatic food
Know about some common types of cancer
Here are some tips to increase fiber for a healthy gut
Everything You Need To Know About Low Back Ache
How To Remove Dark Circles
What is Psoriasis and How do we Treat
What is Black Fungus | Where is it Present
Covid 19 Recovery Exercises at Home
Nutrition2 years ago
Dhanteras special: Make a smart investment with Iron-rich foods and diet tips
Celebrity Health2 years ago
Cancer survivor Manisha Koirala writes about “Arduous Journey Of Treatment”
FEATURED HEALTH TOPICS2 years ago
Are you taking too much vitamin D?
Covid2 years ago
Post-Covid fatigue is most prevalent in diabetes patients: Study
HEALTH NEWS2 years ago
Why do you need to develop a healthy-eating plan During Diabetes or Pre-diabetes state
FEATURED HEALTH TOPICS2 years ago
Tips for Asthma patients to enjoy a safe Diwali
Nutrition2 years ago
Amazing health benefits of Jackfruit
TRENDING2 years ago
Enjoy Diwali without gaining weight