Vaccination and booster dose plans should have context in the background and be informed by epidemiological evidence
Six weeks after the Indian government announced ‘precautionary shots’ or ‘third dose’ of COVID-19 vaccines for select populations, there have been four relevant developments. First, two COVID-19 vaccines have received ‘conditional market authorisation’. A second, phase three clinical trial involving a booster dose of a nasal COVID-19 candidate vaccine has been approved. Third, the Omicron wave has spread extensively across the country. Fourth, Rs 5,000 crore has been allocated for COVID-19 vaccines in the Union Budget 2022-23.
What do these new developments mean for the COVID-19 vaccination and booster dose strategy in India? Do healthy adults need boosters and when? Is the budgetary allocation sufficient for COVID-19 vaccines? Let us discuss these.
market authority
The news of Covishield and Covaxin’s market authority has generated a lot of interest. Many have thought that from now on, anyone who wants can buy a COVID-19 vaccine and administer it on their own volition or on a doctor’s prescription. This is what ‘market authority’ usually means for most medical products. However, these two COVID-19 vaccines have not received absolute but a ‘conditional’ market authorisation. So, for the general public, nothing has changed. The government will continue to regularize the vaccine administration as before. Target groups already eligible (as per national guidelines), will continue to receive vaccines through authorized COVID-19 vaccination centres. The only effective change is for vaccine manufacturers.
By submitting safety and efficacy data to the national drug regulator every fortnight, they can now submit this data every six months.
nasal vaccine
Even though in the clinical trial phase, and none have been authorized yet, nasal COVID-19 vaccines have always generated great interest for a number of reasons. One, ease of administration (and thus less biomedical waste) without needles and syringes. Two, given that the COVID-19 vaccines currently in use in India have limited evidence regarding their role in reducing transmission, nasal vaccines, via mucosal antibodies, are better able to reduce transmission. likely to perform. Third, nasal vaccines may be useful for children in whom the primary objective of COVID-19 vaccination is to reduce transmission, rather than individual benefit. Fourth, the world needs more vaccines to ensure widespread availability and address vaccine disparity. Five, the combination use of injectable and nasal vaccines can provide mixed protection against serious disease and reduce transmission. Such an approach may be useful in mitigating the impact of the ongoing COVID-19 pandemic, as well as in the control of outbreaks in the post-pandemic period. However, a flip side of nasal vaccines and mucosal immunity is that protection is usually short-lasting.
Epidemiological data and modeling estimates suggest that by the time the omicron wave ends in any setting, 50% to 70% of the population may be exposed. A South African study found that exposure to Omicron in a person with a previous infection or vaccination resulted in a 14-fold increase in antibodies, which confers protection against future delta-type infections. The role of hybrid immunity obtained after natural infection in combination with two shots of COVID-19 vaccines provides better protection than vaccines alone. As an omicron wave is sweeping India, the country is in a phase of what might be called ‘sandwich immunity’ – hybrid immunity complemented by another layer of natural infection.
In this background, there is no reason for any urgency to administer a COVID-19 booster dose to healthy adults aged 18 to 60 years. Likewise, children are at low risk of developing serious illness and infection, and with further exposure to children in the ongoing omicron boom, vaccination of children under the age of 15 is also not necessary.
This does not mean that any population sub-group in the 18-59 year band will never need a COVID-19 vaccine booster. One, immunity, and thus protection from respiratory viruses (ie, SARS-CoV-2), whether after vaccination or natural infection, diminishes over time. Two, mutations in SARS-CoV-2 are common and there remains the potential for new forms of concern to emerge with the potential to bypass immunity (provided by natural infection or vaccination). Therefore, it is likely that a large proportion of the adult population may require boosters, albeit at relatively longer intervals. In addition, once there is evidence about the effectiveness of additional doses of COVID-19 vaccines (being used in India) in immunocompromised individuals, a third dose is recommended for such adults of any age group. should be done.
Funding of COVID-19 vaccines is a major operational issue. Soon after the Union Budget 2022-23, there were concerns that the allocation of ₹5,000 crore for COVID-19 vaccines may be inadequate. However, an objective assessment suggests that this may be sufficient. The Indian government, last year, had reportedly made an Advance Market Commitment (AMC) with the makers of Corbevax (Biological E Ltd) for 30 crore shots and made a partial payment of ₹1,500 crore in advance. Hence, advance payment would be sufficient for 10 crore doses. The budgetary allocation for the next financial year could be substantial for procuring 20 crore to 33 crore doses, depending on the share of orders for various COVID-19 vaccines. Besides, the balance of stock of COVID-19 vaccines already procured in the current financial year is likely to be up. These doses are likely to be sufficient to vaccinate the remaining eligible population and to give boosters to eligible population sub-groups (currently and in the future).
make good use of the time
In response to the pandemic, efforts are made to reduce and prevent any transmission. However, a fresh wave also has a silver lining. Any natural infection results in the development of immunity. Therefore, the ongoing third wave gives India some time to decide on rolling out boosters for additional population sub-groups. This time should be used for some reflection and work. First, in epidemics, epidemics, outbreaks and epidemiology, the context or local situation matters a lot. India’s context is very different from other countries due to the relatively low average population age, use of various COVID-19 vaccines and vaccination of most of the population after natural infection in the second wave. Some. Therefore, data used by other countries in deciding on vaccine effectiveness and boosters cannot and should not be used for India. Such decisions should be based on local data and evidence. For example, Denmark decided not to vaccinate against COVID-19 to children aged 5–12 years after analyzing local evidence. Some of the vaccines given to children in India, i.e. BCG against TB or Japanese Encephalitis (JE) vaccines are not part of the vaccination programs of many countries. These are just a few examples of context and use of local data.
Second, the success of any vaccination program depends on the participation of citizens. It is time science determines the COVID-19 vaccination strategy. Let us, as citizens, not demand boosters for any adult age group. Let us not rush to vaccinate children below 15 years of age. Let us not associate vaccination with school attendance. Children do not need vaccinations to go to school. Unscientific and misinformation public discourse has been an ongoing challenge in India’s COVID-19 pandemic response. Therefore, governments at all levels need to advance transparent and timely science communication around vaccines and through reliable sources.
Third, vaccine- and vaccination-specific policy questions need to be identified. Next, analyze COVID-19 disease and vaccine data and link them to clinical outcomes to assess effectiveness against SARS-CoV-2 variants and answer as many policy questions as possible. For policy questions that are not answered by available data, this needs to be supplemented by conducting primary research, both clinical and epidemiological.
India’s COVID-19 vaccination campaign has matured with commendable coverage: around 95% of eligible adults with one shot and 75% of eligible adults with both shots. However, the work is still incomplete. Adequate COVID-19 vaccine supply or high vaccine coverage in adults is not reason enough to open up booster doses to additional age groups. The strategy for COVID-19 vaccination and booster dose should be informed by taking into account the context in the background and fully emerging scientific and epidemiological evidence. Also, instead of just focusing on COVID-19 vaccines and boosters – in weeks and months – we, as a society, need to come to a consensus and a road to ‘live with SARS-CoV-2’. Map preparation is required.
Dr. Chandrakant Laharia, a physician-epidemiologist, is affiliated with the New Delhi-based Foundation for People-Centric Health Systems.
A dose of science in vaccination strategy
Vaccination and booster dose plans should have context in the background and be informed by epidemiological evidence
Six weeks after the Indian government announced ‘precautionary shots’ or ‘third dose’ of COVID-19 vaccines for select populations, there have been four relevant developments. First, two COVID-19 vaccines have received ‘conditional market authorisation’. A second, phase three clinical trial involving a booster dose of a nasal COVID-19 candidate vaccine has been approved. Third, the Omicron wave has spread extensively across the country. Fourth, Rs 5,000 crore has been allocated for COVID-19 vaccines in the Union Budget 2022-23.
What do these new developments mean for the COVID-19 vaccination and booster dose strategy in India? Do healthy adults need boosters and when? Is the budgetary allocation sufficient for COVID-19 vaccines? Let us discuss these.
market authority
The news of Covishield and Covaxin’s market authority has generated a lot of interest. Many have thought that from now on, anyone who wants can buy a COVID-19 vaccine and administer it on their own volition or on a doctor’s prescription. This is what ‘market authority’ usually means for most medical products. However, these two COVID-19 vaccines have not received absolute but a ‘conditional’ market authorisation. So, for the general public, nothing has changed. The government will continue to regularize the vaccine administration as before. Target groups already eligible (as per national guidelines), will continue to receive vaccines through authorized COVID-19 vaccination centres. The only effective change is for vaccine manufacturers.
By submitting safety and efficacy data to the national drug regulator every fortnight, they can now submit this data every six months.
nasal vaccine
Even though in the clinical trial phase, and none have been authorized yet, nasal COVID-19 vaccines have always generated great interest for a number of reasons. One, ease of administration (and thus less biomedical waste) without needles and syringes. Two, given that the COVID-19 vaccines currently in use in India have limited evidence regarding their role in reducing transmission, nasal vaccines, via mucosal antibodies, are better able to reduce transmission. likely to perform. Third, nasal vaccines may be useful for children in whom the primary objective of COVID-19 vaccination is to reduce transmission, rather than individual benefit. Fourth, the world needs more vaccines to ensure widespread availability and address vaccine disparity. Five, the combination use of injectable and nasal vaccines can provide mixed protection against serious disease and reduce transmission. Such an approach may be useful in mitigating the impact of the ongoing COVID-19 pandemic, as well as in the control of outbreaks in the post-pandemic period. However, a flip side of nasal vaccines and mucosal immunity is that protection is usually short-lasting.
Epidemiological data and modeling estimates suggest that by the time the omicron wave ends in any setting, 50% to 70% of the population may be exposed. A South African study found that exposure to Omicron in a person with a previous infection or vaccination resulted in a 14-fold increase in antibodies, which confers protection against future delta-type infections. The role of hybrid immunity obtained after natural infection in combination with two shots of COVID-19 vaccines provides better protection than vaccines alone. As an omicron wave is sweeping India, the country is in a phase of what might be called ‘sandwich immunity’ – hybrid immunity complemented by another layer of natural infection.
In this background, there is no reason for any urgency to administer a COVID-19 booster dose to healthy adults aged 18 to 60 years. Likewise, children are at low risk of developing serious illness and infection, and with further exposure to children in the ongoing omicron boom, vaccination of children under the age of 15 is also not necessary.
This does not mean that any population sub-group in the 18-59 year band will never need a COVID-19 vaccine booster. One, immunity, and thus protection from respiratory viruses (ie, SARS-CoV-2), whether after vaccination or natural infection, diminishes over time. Two, mutations in SARS-CoV-2 are common and there remains the potential for new forms of concern to emerge with the potential to bypass immunity (provided by natural infection or vaccination). Therefore, it is likely that a large proportion of the adult population may require boosters, albeit at relatively longer intervals. In addition, once there is evidence about the effectiveness of additional doses of COVID-19 vaccines (being used in India) in immunocompromised individuals, a third dose is recommended for such adults of any age group. should be done.
Funding of COVID-19 vaccines is a major operational issue. Soon after the Union Budget 2022-23, there were concerns that the allocation of ₹5,000 crore for COVID-19 vaccines may be inadequate. However, an objective assessment suggests that this may be sufficient. The Indian government, last year, had reportedly made an Advance Market Commitment (AMC) with the makers of Corbevax (Biological E Ltd) for 30 crore shots and made a partial payment of ₹1,500 crore in advance. Hence, advance payment would be sufficient for 10 crore doses. The budgetary allocation for the next financial year could be substantial for procuring 20 crore to 33 crore doses, depending on the share of orders for various COVID-19 vaccines. Besides, the balance of stock of COVID-19 vaccines already procured in the current financial year is likely to be up. These doses are likely to be sufficient to vaccinate the remaining eligible population and to give boosters to eligible population sub-groups (currently and in the future).
make good use of the time
In response to the pandemic, efforts are made to reduce and prevent any transmission. However, a fresh wave also has a silver lining. Any natural infection results in the development of immunity. Therefore, the ongoing third wave gives India some time to decide on rolling out boosters for additional population sub-groups. This time should be used for some reflection and work. First, in epidemics, epidemics, outbreaks and epidemiology, the context or local situation matters a lot. India’s context is very different from other countries due to the relatively low average population age, use of various COVID-19 vaccines and vaccination of most of the population after natural infection in the second wave. Some. Therefore, data used by other countries in deciding on vaccine effectiveness and boosters cannot and should not be used for India. Such decisions should be based on local data and evidence. For example, Denmark decided not to vaccinate against COVID-19 to children aged 5–12 years after analyzing local evidence. Some of the vaccines given to children in India, i.e. BCG against TB or Japanese Encephalitis (JE) vaccines are not part of the vaccination programs of many countries. These are just a few examples of context and use of local data.
Second, the success of any vaccination program depends on the participation of citizens. It is time science determines the COVID-19 vaccination strategy. Let us, as citizens, not demand boosters for any adult age group. Let us not rush to vaccinate children below 15 years of age. Let us not associate vaccination with school attendance. Children do not need vaccinations to go to school. Unscientific and misinformation public discourse has been an ongoing challenge in India’s COVID-19 pandemic response. Therefore, governments at all levels need to advance transparent and timely science communication around vaccines and through reliable sources.
Third, vaccine- and vaccination-specific policy questions need to be identified. Next, analyze COVID-19 disease and vaccine data and link them to clinical outcomes to assess effectiveness against SARS-CoV-2 variants and answer as many policy questions as possible. For policy questions that are not answered by available data, this needs to be supplemented by conducting primary research, both clinical and epidemiological.
India’s COVID-19 vaccination campaign has matured with commendable coverage: around 95% of eligible adults with one shot and 75% of eligible adults with both shots. However, the work is still incomplete. Adequate COVID-19 vaccine supply or high vaccine coverage in adults is not reason enough to open up booster doses to additional age groups. The strategy for COVID-19 vaccination and booster dose should be informed by taking into account the context in the background and fully emerging scientific and epidemiological evidence. Also, instead of just focusing on COVID-19 vaccines and boosters – in weeks and months – we, as a society, need to come to a consensus and a road to ‘live with SARS-CoV-2’. Map preparation is required.
Dr. Chandrakant Laharia, a physician-epidemiologist, is affiliated with the New Delhi-based Foundation for People-Centric Health Systems.
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