Study on the effect of ‘covid vaccines’ soon

NIV scientist Pragya Yadav, who isolated the first SARS-CoV2 virus in 2020, said the study would reveal why people continue to contract Covid even after getting a booster shot.

Asked whether there is a need for a fourth dose, Yadav said in an interview, “Before talking about the fourth dose, we should increase the coverage of the third precautionary dose to boost the immune response.”

Only about 228.7 million Indians have received the third dose – the booster shot – so far.

While discussing the current testing strategy, Yadav said that the government should increase the number of samples taken for genome surveillance. At the moment, only 5% of samples are taken for genome surveillance, which he said is insufficient to determine the genome in circulation. Edited excerpts:

How do you see the current Covid surge in the country,

When Omicron emerged last year there was a lot of anxiety and everyone was in a panic. Gradually, several Omicron variants appeared, which were also reported by other countries. Fortunately, India did not suffer any major surge. Currently, we have over 37,000 active cases. This is the time for everyone to be alert and take precautions. When the XBB variant, a recombinant variant of Omicron emerged with two variants—BA.2.75 and BA.2.10.1—there was a concern that cases would increase. However, cases of the emerging XBB.1.15 variant did not increase as in other countries. In India, XBB.1.16 is currently prevalent with approximately 75% of the total cases. Certainly, it will not be as bad as what we saw in Delta as Omicron is mild and most cases are asymptomatic. But from a public health perspective, yes there is alarm, and we follow safe practices as much as possible including mask use, hand hygiene and physical distancing.

What is the situation in other countries?

XBB.1.16 is now slowly rolling out to approximately 28 countries. According to currently available data, although cases in the US have increased by 5% to 7%, the virus XBB.1.15 still dominates most parts of the country. While it has been shown in the past that dominant variants replicate more quickly, XBB.1.16 has a 1.5-fold transmission advantage over other variants due to its higher R0 number.

India has hybrid immunity due to natural infection and excellent vaccine programmes. However, several studies have proved that vaccines cannot prevent the infection but can reduce the severity and hospitalization and mortality. Viruses have a tendency to mutate, and some of these changes may make them more likely to survive the immune response generated by vaccination or natural infections, but vaccination will still protect against death and severity.

Are there any studies to understand the immune escape response to NIV vaccine?

Vaccine neutralizing studies are now being planned to understand vaccine response.

Deaths are being told. Are they a cause for concern?

It is time to monitor these cases and analyze the data properly. Most of these deaths affect the elderly and those who have either not been vaccinated or have co-morbidities with COVID-19.

Do we need a fourth dose of vaccine?

Before we talk about the fourth dose, we must increase the coverage of the third precautionary dose to enhance the immune response. The vaccines currently used in India are mostly based on the SARS-CoV-2 variant of the Wuhan strain. Although there have been significant changes in Omicron, several studies have proved that hybrid/booster immunity still protects against seriousness and deaths. Booster vaccination provides long-term cellular immunity.

Influenza (H3N2) on the rise along with the Covid surge? Do you think there is a risk of co-infection?

To strengthen the detection of COVID-19, surveillance was initiated among SARIs/ILIs. Nevertheless, the incidence of such co-infection is not particularly high and to date only a few cases of co-infection of COVID-19 and H3N2 have been reported.

The coverage of booster dose is low. Why the hesitation for booster dose?

Hesitancy about the booster dose vaccine can be due to many reasons, including disseminating misinformation and non-mandatory booster doses.

Do we need a fourth dose of vaccine?

Before we talk about the fourth dose, we must increase the coverage of the third precautionary dose to enhance the immune response. The vaccines currently used in India are mostly based on the SARS-CoV-2 variant of the Wuhan strain. Although there have been significant changes to Omicron, several studies have proven that hybrid/booster immunity still protects against severities and deaths. Booster vaccination provides long-term cellular immunity.

Influenza (H3N2) on the rise along with the Covid surge? Do you think there is a risk of co-infection?

To strengthen the detection of COVID-19, surveillance was initiated among SARIs/ILIs. Nevertheless, the incidence of such co-infection is not particularly high and to date only a few cases of co-infection of COVID-19 and H3N2 have been reported.

The coverage of booster dose is low. Why the hesitation for booster dose?

Hesitancy about the booster dose vaccine can be due to many reasons, including disseminating misinformation and non-mandatory booster doses.

What kind of testing strategy should be in place now?

Right now patients coming to hospitals with symptoms are being tested. However, to improve testing, random sampling may be conducted at different locations at different entry ports. Currently, fewer samples are being tested, including sequencing only 5% of these samples, this percentage can be increased, which will aid in the generation of additional genomic data.

Right now patients coming to hospitals with symptoms are being tested. However, to improve testing, random sampling may be conducted at different locations at different entry ports. Currently, fewer samples are being tested, including sequencing only 5% of these samples, this percentage can be increased, which will aid in the generation of additional genomic data.