Delhi Covid Surge: New Omicron Sub-Variant Discovered As Covid Cases And Positivity Rate Rise Amid Festive Season

The majority of Covid-19 patients in a study conducted Delhi's Lok Nayak Jai Prakash Narayan (LNJP) Hospital have been found to be infected with a new sub-variant of the Omicron variant of coronavirus. 

The BA 2.75 sub-variant has been detected in the majority of 90 people who were part of the study at LNJP hospital, which is Delhi government's mainstay hospital for Covid-19.

The new sub-variant has surfaced at a time when Delhi is witnessing a surge in daily Covid-19 cases, hospitalisation, and deaths, which come in the midst of festive season when people are travelling and large gatherings are also expected to take place in markets and social events in light of the Independence Day. 

Here we explain the ongoing Covid-19 surge in Delhi through numbers, what the newly discovered sub-variant is, what the experts have said of the surge, and what the Union government has advised Delhi and other states.

Delhi Covid-19 surge in numbers

Delhi has touched the seven month high twice in terms of daily infections in last 10 days. 

On August 5, Delhi reported 2,423 Covid-19 daily cases, the highest in nearly seven months. That record last for less than a week. 

On August 11 (Thursday), Delhi reported 2,726 daily Covid-19 cases, breaking the seven-month record set just six days back. 

Daily deaths too have witnessed a spike. On August 12 (Friday), Delhi reported 10 Covid-related deaths in the past 24 hours, the highest in six months. 

The rise in infections has been consistent as Delhi has now reported over 2,000 daily Covid-19 cases for 10 days in a row. 

The positivity rate has also been consistently high lately. On August 7, Delhi reported the positivity rate of 17.85, the highest since January 21.

Hospitalisations, severe disease too on the rise

Hospitalisations are associated with the severity of the disease as when patients are asymptomatic or have mild symptoms, they isolate at home. 

The rise in hospitalisation suggests an increase in the severity of the disease. Hospitalisations as well as patients requiring ventilators have doubled in the last two weeks. 

Around 6 per cent of Covid-19 hospital beds are occupied in Delhi as of August 12. The number was around 3 per cent on July 31. 

On August 12, 128 people were on oxygen support in Delhi hospitals and 15 were on ventilator.

On July 31, 70 people were on oxygen support in Delhi hospitals and eight were on ventilator. 

Therefore, hospitalisations have almost doubled in the last two weeks, according to numbers released by Delhi Health Department. 

What is BA 2.75 Omicron sub-variant?

All viruses evolve over time and acquire mutations, which lead to the creation of its many "variants". 

The SARS-CoV-2 virus, which causes Covid-19 disease, has evolved into a number of variants, such as Delta and Omicron. 

These variants further split and branch to form sub-lineages called "sub-variants". There can be many sub-variants of a variant. For example, the Delta variant that was behind India’s deadly second Covid-19 wave is known to have up to 200 sub-variants.

The BA 2.75 is one of the many known Omicron sub-variants. Other dominant Omicron sub-variants are BA 4 and BA 5. The World Health Organization (WHO) on July 6 said that BA 2.75 was first reported in India and had, by July 6, spread to 10 other countries.

Health.com notes that BA 2.75 has mutations on its spike proteins similar to the BA.4 and BA.5 that could help it bypass the immune system more easily. 

It quoted Cedars-Sinai Hospital's Associate Director Jasmine Plummer as saying that BA 2.75 "appears to have eight additional mutations that might give it the edge when it comes to replicating and spreading, even as compared to the BA.4 and BA.5 strains".

This strain discovered in Delhi might be behind the surge, according to one expert.

"Clinically this surge is mild, possibly caused by a new sub-variant of Omicron," said Dr Nikhil Modi, respiratory medicine specialist at Delhi's Indraprastha Apollo Hospital to The Indian Express. 

Festive season and Covid-inappropriate behaviour

The surge has come with the festive season when large social gatherings are expected. People also travel to their family and relatives' places in large numbers.

Incresed mobility with poor adherance to Covid-19 norms such as not wearing masks and not ensuring physical distancing breeds a fertile ground for Covid-19. 

Besides people not wearing masks and not distancing physically, reports have also surfaced noting that enthusiasm among people for coronavirus vaccine's booster doses is also waninig. Experts have repeatedly stated that vaccination against coronavirus is a must and is key to preventing severe illness. Doctors have been urging people to get their booster doses whenever due and not prolong it or avoid it due to any vaccine hesitancy. 

In a letter on August 5, the Union government also emphasised the importance of increasing the pace of vaccination.  

"States should aim to increase the pace of vaccination for all eligible population and accelerate the administration of free precaution doses for 18-plus eligible population at all Government Covid Vaccination Centres (CVCs) under the 'COVID Vaccination Amrit Mahotsav' till September 30," said Union Health Secretary Rajesh Bhushan in a letter to Delhi and six other states.

What are experts saying?

Besides reasons listed above, experts have highlighted that comorbidities and weather are also playing a role in the surge.

Dr Sameer Bhati, Director of Star Imaging and Path Lab, told ANI that immunity is lower after monsoon season and people are known to get down with viral infections. Covid-19 is also a viral infection, caused by SARS-CoV-2 virus, one of the many known types of coronaviruses. 

He said, "Especially in comorbid patients, immunity seems to be low irrespective of the vaccination and even many young people have also avoided their booster doses while the Covid-appropriate behaviour is followed the least...Secondly, during the post-monsoon season, immunity gets lower, and other viral infections also prevail, so the chances of getting infections increase."

The symptoms in Delhi's Covid-19 surge include high fever, sore throat, chills, itching, and irritation. Bacterial infections are also hitting Covid-19 patients.

Dr Modi, cited above, told The Express, "The high fever lasts for about three odd days, starts settling by the fourth day and then there is gradual remission between the fifth and seventh days. What’s new is chest congestion or bronchitis brought on by a supplementary bacterial infection that’s setting in once the fever starts subsiding."

"There has been an upsurge in Covid cases both in OPD and those requiring hospitalisation. Symptoms mostly are high-grade fever lasting for three to four days alongwith throat itching, irritation, cough, and cold. These patients recover fast," said Dr Vikas Maurya of Fortis Shalimar Bagh to ANI.

Dr Ambrish Mithal of Max HealthCare said in a tweet that sore throat is a prominent symptom in the current surge in Delhi.

"Warm saline gargles, sips of warm water with honey, lozenges and home remedies are the solutions. Antibiotics don't help in most cases. Taking rest is important. Plenty of water to ensure adequate hydration really helps," said Dr Mittal on Twitter. 

Centre has sent two advisories to states

In a sign that that the Union government has acknowledged the surge, the Union government has written twice to states within the last 10 days, urging them to increase vacciantions, ensure adequate testing, and avoid large gatherings in light of the festive season. 

In the August 5 letter, cited above, the Union government noted that it is critical to ensure adequate testing is undertaken in all the districts of the states while maintaining the recommended share of RT-PCR and antigen tests. The Centre added that states must also closely monitor districts reporting higher cases, positivity rates and clusters to prevent further spread of infection. 

In the second advisory on Friday (August 12), the Centre said, "As a precaution, against Covid-19, large congregations in the ceremony be avoided. It is imperative that Covid guidelines are followed."

The Centre has also urged people to wear masks, maintain physical distancing, and sanitise their hands.

(With PTI inputs)