Covid Delta Variant

 As vaccination drives across the globe started to give us hope of returning to normal, we were slammed by the various variants of the coronavirus. The Delta variant is perhaps the most debated variant of the lot right now. Through the rest of this blog, we’ll be looking into the Covid Delta Variant and the Delta Plus Variant.

Before we learn more about the Covid Delta variant, let us try to understand what some of these terms mean. 

What is a variant?

Viruses constantly undergo mutations and the formation of new variants is expected. When viruses get a chance to spread like in the case of the pandemic, the virus undergoes more replications. When it replicates more, the chance that it can undergo a change or mutate increases as well.

Usually, these mutations make no difference to the functioning of the virus or its ability to spread and cause infections. But sometimes, the mutations may alter the virus’s genetic material causing its properties to change. In some mutants, the transmission may occur faster or slower, the severity of the illness may increase or decrease, and so on.

A variant is referred to as a new strain if it shows distinct physical features as compared to the original virus. 

Variants are classified into the following based on their severity, potential impact on Covid safety measures like vaccines, diagnostics, and so on.

Variant of Interest

A variant of interest has been predicted or expected to reduce the effectiveness of antibodies, vaccines, or predicted increased spread rate. 

Attributes of a VoI 

1. Genetic changes may affect the transmission, diagnostics, therapeutics, or immune response.

2. The cause of infections among some, like an outbreak cluster.

3. Limited expansion or prevalence.

Variant of Concern

A variant is classified as a Variant of Concern if there is evidence of an increase in transmissibility, increased severity including fatalities, significant reduction in the effectiveness of antibodies.

Attributes of a VOC

1. Widespread irregularities with diagnostics.

2. Evidence of significant reduction in response to therapies or treatment methods or a considerable reduction in the effectiveness of antibodies.

3. Evidence of increased transmission and severity.

Currently, there are multiple variants spread out across the world including,

B.1.1.7(Alpha): First seen in the United Kingdom, also called the British strain.

B.1.351(Beta): First seen in South Africa and is also known as South African strain.

P.1(Gamma): First seen in Brazil, it is also known as the Brazilian strain.

B.1.617.2(Delta): The Delta strain was first spotted in India and hence it is also known as the Indian strain.

These variants are the most prominent amongst the variants spreading now. These variants have also been linked to increased transmissibility and can potentially lead to a higher number of cases.

What is the Covid Delta Variant?

The Covid Delta Variant or the B.1.617.2 is a form of the SARS-CoV-2 virus, first identified in India around April this year. The Delta Variant has since spread to about 92 countries across the globe.

Evidence suggests that the variant has considerably higher transmissibility. The Delta variant is also suspected to be behind the recent outbreaks in several countries. For these reasons, the World Health Organisation(WHO) has classified it as a variant of concern(VOC).

The WHO declares a variant to be a VOC if it has increased transmissibility, higher virulence, or a decrease in public health measures or available resources. It may also consult the WHO SARS-CoV-2 Virus Evolution Working Group before doing so and proceed according to their input.

 

Spread of Delta Variant

Studies suggest that the Delta variant has perhaps the highest transmissibility. It is almost forty to sixty percent more transmissible than the Alpha variant and about two and a half times as much as the original strain.

Delta, due to its quick and easy transmission has turned out to be a dominant variant in several countries including, the UK, Singapore, Russia, Indonesia, India. It has been flagged as a Variant of Concern by the WHO since May 2021. 

As of June 29th, the Delta strain was reported in around 96 countries, but the WHO suggests that this could be an underestimate as the sequencing technology required to identify the strains is limited. With the increased transmissibility, experts predict that the Delta variant will outcompete other variants in the coming months. 

Another notable characteristic is that the Delta variant has found itself spreading even in communities or countries with high vaccination rates. Additionally, the hospitalization rates are much higher with the Delta variant, up by a whopping 85% in comparison to the Alpha variant.

The Delta variant poses a severe risk, especially for unvaccinated people. Reports also suggest that the Delta variant may cause more severe symptoms than its predecessors. 

 

What is the Covid Delta plus variant?

The Delta plus variant is a mutation of the Delta Variant. The variant has higher transmissibility with resistance to some drugs and treatments. The variant is also known as AY.1 spreads 60% faster than the Delta variant, which makes it about 4 times more than the original strain. This variant also binds swiftly to the lungs. 

India, the country of origin has declared the variant to be a variant of concern. WHO experts suggest that vaccination along with masks are crucial to combat the Delta plus variant. 

Studies are still ongoing when it comes to the Delta plus variant and not much can be told at this point. Wear masks and maintain social distancing measures at all times. Get vaccinated as soon as you can.

 

Diagnostic tests

The current diagnostic tests can detect cases of Covid-19 infections caused by the new variants. However, to identify the different variants distinctly sequential PCR tests or Genomic surveillance is done.

Instructions are encoded into the genes to build the viruses, by Genomic surveillance scientists can decode these genes and understand the virus better. Genomic sequencing also lets them study how the variants change over time, how the changes impact the characteristics of the virus, and use this information to evaluate its impact on public health.

The different variants show subtle differences in the spike proteins, hence most diagnostic tests are designed such that they not only check for spike proteins but also other conserved proteins. 

As of now, Antigen Tests are still found to be effective in detecting Covid infections. However, in the case of molecular tests, the same cannot be said. The effectiveness of Molecular tests largely depends on the number of genes and the location of genes the test targets.

 

Are vaccinations effective?

The Covid-19 vaccines that have been approved by WHO or other Public Health Administrative Bodies such as the CDC, FDA, DCGI, or EMA continue to be safe. These vaccines will provide at least some protection against the new variants.

Vaccines evoke a broad immune response that involves a host of antibodies and cells, hence a change or mutation in the virus will not render these vaccines useless. Additionally, these vaccines can be tweaked by changing the compositions to protect against any new variants in case these vaccines aren’t as effective as expected.

Vaccine manufacturers and development programs may have to incorporate some changes into their development and manufacturing processes. For example, they may have to include multiple strains during development and provide booster shots for additional immunity. 

Scientists and healthcare experts are working continuously to collect and make sense of data about the variants and vaccines. More reliable information will be available in the coming days.

 

Tackling the variants

Health experts suggest that vaccines alone may not be sufficient in tackling the new variants of the virus. Getting vaccinated is indeed a top priority. But at the same time, we must practice other safety measures like wearing masks, social distancing, and proper sanitary hygiene. 

To stop the spread of the variants and prevent further mutations, stopping the spread is crucial. Measures to reduce transmission like frequent washing of hands with soap and water or sanitizer, avoiding crowds, proper ventilation, and physical distancing do work to curb the transmission of the virus irrespective of the variant. 

Amping up vaccination efforts by rolling out more vaccines and distributing them swiftly will prove useful in stopping the spread. Prioritizing equitable access to vaccines is critical to successfully tackling the Covid-19 pandemic. As more people are getting vaccinated, we expect the circulation to decrease hence causing fewer mutations. 

Do not fall prey to false information. Do your research and share information from reliable sources only. To read about some common Covid-19 myths, click here.