Daily Current Affairs 29.08.2021 (Why are hydropower projects in the Himalayas risky?, Plasmid DNA vaccine ZyCoV-D is safe and effective for adolescents, BCG vaccine: 100 years and counting)

Daily Current Affairs 29.08.2021 (Why are hydropower projects in the Himalayas risky?, Plasmid DNA vaccine ZyCoV-D is safe and effective for adolescents, BCG vaccine: 100 years and counting)


1.Why are hydropower projects in the Himalayas risky?

Environment Ministry told the SC earlier this month that seven hydel projects in the region can go ahead

The story so far: The Environment Ministry, in an affidavit placed in the Supreme Court earlier this month, has disclosed that it has permitted seven hydroelectric power projects, which are reportedly in advanced stages of construction, to go ahead. One of them is the 512 MW Tapovan Vishnugadh project, in Joshimath, Uttarakhand that was damaged by a flood in February.

What’s the history of hydel projects in the Himalayas?

In the aftermath of the Kedarnath floods of 2013 that killed at least 5,000 people, the Supreme Court had halted the development of hydroelectric projects in Uttarakhand pending a review by the Environment Ministry on the role such projects had played in amplifying the disaster.

A 17-member expert committee, led by environmentalist Ravi Chopra, was set up by the Ministry to examine the role of 24 such proposed hydroelectric projects in the Alaknanda and Bhagirathi basin, which has the Ganga and several tributaries. The Chopra committee concluded that 23 projects would have an “irreversible impact” on the ecology of the region.

Following this, six private project developers, whose projects were among those recommended to be axed, impleaded themselves in the case on the ground that since their projects had already been cleared for construction before the Kedarnath tragedy, they should be allowed to continue.

The SC directed a new committee to be set up to examine their case. This committee, led by Vinod Tare of the Indian Institute of Technology, Kanpur, concluded that these projects could have a significant environmental impact.

The Environment Ministry in 2015 set up yet another committee, led by B.P. Das, who was part of the original committee, but had filed a “dissenting report”. The Das committee recommended all six projects with design modifications to some.

The Water Resources Ministry, then led by Minister Uma Bharti, has been consistently opposed to hydropower projects in the Ganga. In charge of the National Mission for Clean Ganga, the Water Ministry has maintained that the cleanliness of the river was premised on minimum levels of water flow in all seasons and the proposed projects could hinder this. By 2019, however, the renamed Jal Shakti Ministry had changed its stance to accommodate seven out of the 24 projects. Its current position is that barring these, it is “not in favour” of new projects in the Ganga river basin.

Though hearings in the Supreme Court are ongoing, this is the first time that the government has a formal uniform position on hydropower projects in the Uttarakhand region.

What are the challenges such projects face?

Following the break in the Raunthi glacier that triggered floods in the Rishiganga river in Uttarakhand on February 7, which washed away at least two hydroelectric power projects — the13.2 MW Rishiganga hydroelectric power project and the Tapovan project, environmental experts have attributed the glacial melt to global warming. Glacier retreat and permafrost thaw are projected to decrease the stability of mountain slopes and increase the number and area of glacier lakes. Moreover, with increased instances of cloudbursts, and intense spells of rainfall and avalanches, residents of the region were also placed at increased risk of loss of lives and livelihood.

How can these conflicts be resolved?

The challenges facing development in the Himalayan region are multi-faceted. The Uttarakhand government has said that it’s paying over ₹1,000 crore annually to purchase electricity and therefore, the more such projects are cancelled, the harder for them to meet their development obligations. Several environmentalists and residents of the region say that the proposed projects being built by private companies allot only a limited percentage of their produced power for the State of Uttarakhand itself. Thus the State, on its own, takes on massive environmental risk without being adequately compensated for it or its unique challenges accounted for. Though the Centre is committed to hydropower projects because it’s a renewable source of power, the ecological damage combined with the reduced cost of solar power means that it has in recent times said that it is not in favour of greenfield hydropower projects in the region. But several environmental activists say that the Centre will continue to prioritise infrastructural development in the region, even if it comes at a heavy environmental cost.

2.‘Plasmid DNA vaccine ZyCoV-D is safe and effective for adolescents’

The reactogenicity of the three-dose vaccine is lesser than that of other COVID-19 vaccines currently used in India, says member of National COVID-19 Task Force

N.K. Arora, a senior member of the National COVID-19 Task Force, speaks about the ZyCoV-D vaccine — the world’s first plasmid DNA vaccine for human use — and how it could be the beginning of a vaccine revolution.Excerpts:

How is Zydus Cadila’s ZyCoV-D vaccine different from the existing COVID-19 vaccines, especially the mRNA vaccines?

ZyCoV-D is the world’s first plasmid DNA vaccine for human use. DNA, or Deoxyribonucleic Acid, contains the genetic code of various components of an organism. For the vaccine, the part of the COVID-19 virus that helps it enter the cell and causes disease is coded. When the vaccine is injected into the human body, it produces that particular part of the virus and stimulates the immune system to generate antibodies and T-cells immunity against the virus.

This DNA piece is enclosed by a membrane called plasmid, and it disintegrates after it has completed its action. This DNA is a laboratory-made structure and is unable to interfere with the genetic composition of humans. The mRNA vaccines are also made with the same principle. These again are laboratory-made structures and not obtained from the actual virus.

Is the vaccine approved for children?

Any new vaccine is first tested on adults and then on children. This holds true for all the currently used paediatric vaccines. Similarly, the COVID-19 vaccines, for example, Covishield, Covaxin and Sputnik, have been used in adults. Covaxin is now being tested in children aged 2-18 years. The key assessment criteria are the safety of the vaccines and their immunogenic capacity in children. ZyCoV-D has also been tested in adolescents between 12 and 17 years. Now, we have the first approved, safe and effective vaccines for adolescents in India.

Is this vaccine safer than the previous one?

The Phase I, II and III trials of ZyCoV-D demonstrated its safety in all age groups. In fact, the reactogenicity of the vaccine, that is, fever, pain, feeling of illness, is much lesser than the other currently used vaccines in India.

Like vaccination for adults, will there be a prioritisation in the paediatric age group as well?

Prioritisation of adults was based on occupation, comorbidities and age. Two criteria were used for the prioritisation: exposure probability and risk of severe disease and death. In children, COVID-19 is mostly asymptomatic or mild; severe disease and death are rare. Like for adults, for children too, the priority will be given to those with comorbidities such as heart disease, chronic kidney, liver, lung diseases and other illnesses.

Secondly, there are 44 crore children in India, out of them 12 crore are in the 12-17 age group. We intend to prioritise adult immunisation and simultaneously start immunising children with comorbidities.

When will the vaccine be available for people? What is the current production capacity of this vaccine?

We are expecting to begin inoculating adults and adolescents with comorbidities by mid-October. For healthy children, COVID-19 vaccination is likely to be launched by the first quarter of 2022. The current production capacity of ZyCoV-D is 1 crore doses per month. It is expected that it will be ramped up to 2-3 crore doses a month in the coming months. We need to understand that the DNA vaccine production line is a slow process and might require technology transfer to other companies as well.

Tell us about the dosage and intervals between doses?

This is a three-dose vaccine, given with a needleless device called jet inject/Pharmajet, which is also painless. Every dose is 2 mg, split into two parts administered at two separate sites to get maximum immune response. All three doses will be given in the same manner at an interval of four weeks each. The vaccine is associated with negligible side-effects and the recipient does not feel any pain or discomfort at the injected site. Even fever or fatigue is uncommon post-vaccination.

Now that the vaccine for children will soon be available, do you think it will be a good idea to send children to school only after they get vaccinated?

As explained earlier, paediatric vaccination can wait. Based on Indian as well as global data, the risk of severe disease and death are rare in children. However, children can spread infection. Adults have almost 15 times higher risk of death and severe disease compared with children below 18 years. So, if adults around them at home or at school are vaccinated, it will form a protective ring arou- nd them. There will be limited virus and disease transmission in that condition.

I strongly feel that parents should send their kids to school without waiting for COVID-19 vaccine for two reasons: one, their risk of developing a severe disease is rare; second, going to school is important for their cognitive, physical and mental development.

Some parents are afraid of sending their children as they fear the third wave. Is the third wave for real?

Personally, I feel that based on the current virus and disease epidemiology, sero-positivity rate and the fact that 90% of the circulating virus is Delta variant, and no new variant of concern has been reported in the past four weeks, it seems we are at the tail-end of the second wave.

The risk of the third wave is there only if people show complacency in following COVID-appropriate behaviour, especially during the coming festival season.

Why in News

Recently, India has started phase I/II clinical trials of Covid-19 vaccine – ZyCoV-D, designed and developed by Zydus (a pharmaceutical company) with support from the Department of Biotechnology (DBT).

  • The adaptive phase I/II clinical trials will assess the safety, tolerability and immunogenicity of the vaccine.
  • The other indigenously developed vaccine – Covaxin – produced by Hyderabad based Bharat Biotech is also underway to start clinical trials.

Key Points

  • Description: ZyCoV-D, a plasmid DNA vaccine, comes under the Vaccine Discovery Programme supported by the Department of Biotechnology under the National Biopharma Mission.
    • Plasmids are circular deoxyribonucleic acid (DNA) vectors that can be used as vaccines to prevent various types of diseases.
  • Pre-Clinical Phase: It was found to initiate a strong immune response in multiple animal species like mice, rats, guinea pigs and rabbits.
    • The antibodies produced by the vaccine were able to neutralize the wild type virus indicating the protective potential of the vaccine candidate.
    • No safety concerns were observed in repeat dose by both intramuscular (directly into muscles) and intradermal (superficial injection into skin) routes of administration.
  • DNA Vaccine Platform: The development of ZyCov-D has established the DNA vaccine platform in the country which is simple to deploy, temperature stable, and consistently manufacturable- thus lowering costs and enhancing the effectiveness of a vaccine.
    • It provides ease of manufacturing the vaccine with minimal biosafety requirements.
    • It has shown much improved vaccine stability and lower cold chain requirements making it easy for transportation to remote regions of the country.
    • Furthermore, the platform can be rapidly used to modify the vaccine in a couple of weeks in case the virus mutates.

National Biopharma Mission

  • It is an industry-academia collaborative mission for accelerating biopharmaceutical development in the country.
  • It was launched in 2017 at a total cost of Rs. 1500 crore and is 50% co-funded by World Bank loan.
  • It is being implemented by the Biotechnology Industry Research Assistance Council (BIRAC).
    • BIRAC is a Public Sector Enterprise, set up by the Department of Biotechnology (DBT), Ministry of Science & Technology.
  • Under this Mission, the Government has launched Innovate in India (i3) programme to create an enabling ecosystem to promote entrepreneurship and indigenous manufacturing in the biopharma sector.
  • Objectives: Development of vaccines, medical devices, diagnostics and biotherapeutics besides, strengthening the clinical trial capacity and building technology transfer capabilities in the country.

3.BCG vaccine: 100 years and counting

BCG works well in some geographic locations and not so well in others

The centenary celebrations of the discovery of insulin have eclipsed another seminal event in the history of medicine that has had significant impact on human health – the first use of BCG (Bacillus Calmette-Guerin), the vaccine against tuberculosis (TB) in humans.

TB is caused by a bacterium called Mycobacterium tuberculosis, belonging to the Mycobacteriaceae family consisting of about 200 members. Some of these cause diseases like TB and leprosy in humans and others infect a wide range of animals. Mycobacteria are also widely dispersed in the environment. In humans, TB most commonly affects the lungs (pulmonary TB), but it can also affect other organs (extra-pulmonary TB).

TB is a very ancient disease and has been documented to have existed in Egypt as early as 3000 BC. Sadly, unlike other historically dreaded diseases like smallpox, leprosy, plague and cholera that have been either eradicated or controlled to a large extent due to advances in science and technology, TB continues to be a major public health problem in the world. According to the WHO’s Global TB Report, 10 million people developed TB in 2019 with 1.4 million deaths. India accounts for 27% of these cases.

BCG was developed by two Frenchmen, Albert Calmette and Camille Guerin, by modifying a strain of Mycobacterium bovis (that causes TB in cattle) till it lost its capacity to cause disease while retaining its property to stimulate the immune system. It was first used in humans in 1921.

Sole vaccine

Currently, BCG is the only licensed vaccine available for the prevention of TB. It is the world’s most widely used vaccine with about 120 million doses every year and has an excellent safety record. In India, BCG was first introduced in a limited scale in 1948 and became a part of the National TB Control Programme in 1962.

One intriguing fact about BCG is that it works well in some geographic locations and not so well in others. Generally, the farther a country is from the equator, the higher is the efficacy. It has a high efficacy in the UK, Norway, Sweden and Denmark; and little or no efficacy in countries on or near the equator like India, Kenya and Malawi, where the burden of TB is higher. These regions also have a higher prevalence of environmental mycobacteria. It is believed that these may interfere with the protective effect against TB. However, in children, BCG provides strong protection against severe forms of TB. This protective effect appears to wane with age and is far more variable in adolescents and adults, ranging from 0–80%. A large clinical trial between 1968-1983, by the ICMR’s National Institute for Research in Tuberculosis (then called the Tuberculosis Research Centre) in Chengalpattu district of Tamil Nadu, indicated that BCG offered no protection against pulmonary TB in adults, and a low level of protection (27%) in children.

India is committed to eliminate TB as a public health problem by 2025. To achieve this goal, we would not only need better diagnostics and drugs but also more effective vaccines. Over the last ten years 14 new vaccines have been developed for TB and are in clinical trials. Of particular interest is a Phase 3 clinical trial by the ICMR, of two vaccines; a recombinant BCG called VPM 1002 and Mycobacterium indicus pranii (MIP). MIP was identified and developed into a vaccine in India. Results of this trial are eagerly awaited.

In addition to its primary use as a vaccine against TB, BCG also protects against respiratory and bacterial infections of the newborns, and other mycobacterial diseases like leprosy and Buruli’s ulcer. It is also used as an immunotherapy agent in cancer of the urinary bladder and malignant melanoma.

In progress

Interestingly, it has been observed that in some countries that have had BCG vaccination as a national policy, the burden of SARS CoV-2 morbidity and mortality was significantly less compared to countries which did not. Clinical trials to know if this is indeed true, are underway, including in India.

In these distressing times of Covid-19, it is interesting to compare development of vaccines for Covid-19 and TB. For Covid-19 in about 18 months,17 vaccines have received emergency use authorization in various countries, and 97 are in clinical trials. For TB, a single vaccine has been in use for the last 100 years and 14 new vaccines are in clinical trials. For R&D of Covid-19 vaccines, US$ 8.5 billion have been earmarked (Global Contributions to ACT- Accelerator, Vaccines category); for TB the amount is US$ 0.117 billion (Global Funding for TB Vaccine Research, 2019). If viewed in the backdrop of the deaths caused by these two diseases (Covid-19 – 1.7 million in 2020; TB – 1.4 million in 2019), one can see the stark inequity in investment in vaccine development.

While we commemorate the centenary of BCG vaccine use in humans, we need to acknowledge that more effective vaccines are needed to reach the targets of TB elimination. The experience and success of development of new vaccines for Covid-19 have shown that this is possible if TB gets similar political, financial and pharmaceutical support.

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