Category Health and Medicine

When vaccination was born

When vaccination was born

On May 14, 1796, Englishman Edward Jenner tested vaccination on a human subject. Building on conventional wisdom, Jenner introduced vaccination against smallpox, a disease that has now been eradicated.

You probably already know this story. Yes, you read that right. When the world was gripped by the COVID-19 pandemic, the race to find a vaccine dominated news across the globe. And among the countless vaccination related stories, the story of Englishman Edward Jenner also found mention on occasions. But considering that we have collectively forgotten a lot of good that we learnt during the height of the pandemic, you wouldn't be judged if you have forgotten Jenner’s story too.

Born in Berkeley, Gloucestershire on May 17, 1749, Jenner was the eighth of nine children born to the vicar of Berkeley, the Reverend Stephen Jenner, and his wife Sarah. He was apprenticed to a local surgeon at the age of 14 and then trained in London. Returning to Berkeley in 1772, he spent much of his career as a doctor in his native town.

Cowpox doesn't kill

During his time as a medical student, Jenner observed that milkmaids who had contracted a disease called cowpox, which caused blistering on cow's udders, did not catch smallpox. While cowpox led to few ill symptoms among these women, smallpox caused severe skin eruptions and high fevers among humans. Believed to have existed for thousands of years, smallpox was one of the most devastating diseases known to humanity and killed millions through the centuries.

Jenner decided to put the conventional wisdom into practice and devised an experiment. On May 14, 1796, Jenner took fluid from a cowpox blister on milkmaid Sarah Nelmes. He inserted the pus taken into an incision on eight-year-old James Phipps' arm.

The eight-year-old experimental subject fell mildly ill with cowpox a few days later, but was well again a week later. While this helped Jenner learn that cowpox could pass from person to person as well as cow to person, his next step was to find out if the experiment would protect Phipps from smallpox.

Ethical debate

Starting on July 1, Jenner repeatedly inoculated Phipps with smallpox matter. While ethicists now debate if such an experiment would be possible today, it was possible in Jenner’s time. And to his relief, the boy, who had been inoculated with cowpox, was now immune to smallpox, just as he had anticipated.

Having succeeded at what he set out to do, Jenner submitted a paper describing his experiment to the Royal Society in 1797. His revolutionary ideas weren't immediately accepted and he was asked for further proof.

Not one to be daunted, Jenner experimented with several others and in every case he was unable to infect them with smallpox if he had vaccinated them, or if they had contracted cowpox earlier naturally. He published all his research in 1798 in a book entitled "An Inquiry into the Causes and Effects of the Variolae Vaccinae; a Disease Discovered in some of the Western Counties of England, Particularly Gloucestershire, and Known by the Name of The Cow Pox". It was Jenner who coined the word "vaccine" from the Latin vacca for cow.

Efficacy wins over people

Jenner was still ridiculed, especially by clergymen, who saw his method of inoculating someone with material from a diseased animal as ungodly and even repulsive. The advantages of vaccination and the protection it offered against smallpox eventually trumped the naysayers, and vaccination slowly caught on.

Having become famous, Jenner was able to spend more time researching and offering developments in his vaccine. He carried out research in certain other areas of medicine as well. He died on January 26, 1823.

Jenner's model was adopted by scientists in the centuries that followed, helping them develop vaccines to numerous deadly diseases. As for smallpox, it was declared eradicated in 1980 by the World Health Organisation following a global vaccination programme. The disease that led to the birth of vaccination is also the only infectious disease to achieve this distinction.

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COVID-19 vaccines in India: quick facts

The year 2021 has brought new developments on the vaccine front. On January 3, India approved the emergency use of two coronavirus vaccines, namely Covishield and Covaxin. When this article was taking shape, nationwide drills were being held to train more than 90,000 health care workers to administer these vaccines. The dry runs were also intended to avoid logistical loopholes during the actual vaccination drive that will cover crores of people across the country. Health Minister Harsh Vardhan said the government expected the first phase of vaccination – targeting around 30 crore people on priority – to be completed by August 2021. While preparations are in full swing, some scientists expressed concern over the rushed approval given to the indigenous vaccine, Covaxin.

Who has developed Covishield and Covaxin?

Covishield is the Indian variant of AZD1222, the vaccine developed by AstraZeneca and University of Oxford. Pune-based Serum Institute of India developed and manufactured Covishield through a licence from Astrazeneca and Oxford.

The overall efficacy of the AstraZeneca/Oxford vaccine has been found to be 70.42%. Serum Institute of India has said it would price the vaccine at Rs. 440 for the government and around Rs. 700-800 for the private market.

Covaxin has been developed by Hyderabad-based Bharat Biotech in collaboration with the Indian Council of Medical Research and the National Institute of Virology. The vaccine is yet to complete late-stage human clinical trials and its efficacy rate has not been released. The price of Covaxin has not been made public

What does “restricted use approval in an emergency situation” mean?

During an emergency such as a pandemic drug regulators may allow vaccines to be given to certain people even when the studies of safety and effectiveness are ongoing. This form of approval is called Emergency Use Authorisation. Normally, the process to approve a new vaccine can take years, sometimes more than a decade. But the COVID-19 pandemic has urged governments around the world to relax certain rules and to not only speed up the process of vaccine development, but also go ahead with emergency use.

Instead of the usual requirement of “substantial evidence of safety and effectiveness, they allow products into the market as long as their benefits are “likely” to outweigh their risks.

In the case of Covishield and Covaxin, Indian pharmaceutical regulator, the Central Drugs Standard Control Organisation (CDSCO), has imposed certain conditions on the vaccines developers. The developers have to continuously submit safety, efficacy and immunogenicity data from their ongoing trials until these are complete.

They also have to submit safety data every 15 days for the next two months, and after that monthly for the duration of their trials.

Who will get vaccinated first?

Covishield will be given in the first phase of the vaccine drive. Union Health Minister Harsh Vardhan said that Covaxin will be used only in ‘clinical trial mode, where consent will be taken and side effects monitored.

The Covishield vaccine will first be given to around one crore healthcare workers in both government and private hospitals. It will also be given to two crore frontline workers associated with the state and central Police department, armed forces, home guard, disaster management and civil defence organisation, prison staff municipal workers and revenue officials engaged in COVID-19 containment, surveillance and associated activities. People above the age of 50 years and those with comorbidities are next in line to get the vaccine.

How will the vaccines be given?

Both Covishield and Covaxin are meant to be administered in two doses and stored at temperatures of 2 degrees C to 8 degrees C. While Covishield will be given between four and 12 weeks apart, the DCGI has not clarified the intervals between the shots of Covaxin. (The vaccines do not need the ultra-cold storage facilities that some others do. They can be stored in refrigerators. This makes them feasible candidates.)

The remaining population will be inoculated after the people on the priority list are covered. Once it is open to the public, beneficiaries will have to register on the COWIN app and submit ID proof for vaccination.

The Union Health Ministry has said that getting vaccinated for COVID-19 will be voluntary. However, it has ‘advised’ all to get vaccinated.

What is CoWIN app?

For a smooth implementation of the COVID-19 vaccination programme, the government has developed the COWIN app, which stands for Covid Vaccine Intelligence Network. Registration on the app is mandatory to receive a vaccine.

Why are some experts concerned about the vaccines’ approval?

Some doctors have criticised a lack of transparency in the approval process.

The main concern is that developers of both the vaccines have not presented to the CDSCO the results of their respective phase 3 efficacy trials conducted on Indian participants, Covishield is backed by phase 3 data from studies in Brazil and the United Kingdom, The data from the “bridging study” showing its vaccine can elicit an immune response in the Indian population comparable with the original AstraZeneca vaccine has not been analysed fully. Further, out of a pool of 1,600 Indian participants, the Serum Institute submitted data pertaining to only 100 volunteers to the CDSCO’s subject expert committee.

In the case of Covaxin, there is no efficacy data. While Bharat Biotech has said that phase 1 and phase 2 trials have shown good results, the drug regulator has simply said the vaccine is safe and effective. Covaxin is expected to be a “backup,” to be deployed only if India faces a surge because of the new coronavirus variant that has been recently identified in the U.K.

 

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HOW DO VACCINATIONS WORK?

In 1796, an English doctor called Edward Jenner (1749-1823) gave the first vaccination. He realized that milkmaids who caught cowpox did not catch the very dangerous disease of smallpox. By injecting the cowpox virus into a child, he was able to vaccinate him against the more serious disease. As the body fights the virus, antibodies are formed in the blood that prevents further infections or infection by some similar viruses. Today, huge vaccination programmers ensure that most children are protected against a range of diseases.

A person may become immune to a specific disease in several ways. For some illnesses, such as measles and chickenpox, having the disease usually leads to lifelong immunity to it. Vaccination is another way to become immune to a disease. Both ways of gaining immunity, either from having an illness or from vaccination, are examples of active immunity. Active immunity results when a person’s immune system works to produce antibodies and activate other immune cells to certain pathogens. If the person encounters that pathogen again, long-lasting immune cells specific to it will already be primed to fight it.

A different type of immunity, called passive immunity, results when a person is given someone else’s antibodies. When these antibodies are introduced into the person’s body, the “loaned” antibodies help prevent or fight certain infectious diseases. The protection offered by passive immunization is short-lived, usually lasting only a few weeks or months. But it helps protect right away.

Infants benefit from passive immunity acquired when their mothers’ antibodies and pathogen-fighting white cells cross the placenta to reach the developing children, especially in the third trimester. A substance called colostrum, which an infant receives during nursing sessions in the first days after birth and before the mother begins producing “true” breast milk, is rich in antibodies and provides protection for the infant. Breast milk, though not as rich in protective components as colostrum, also contains antibodies that pass to the nursing infant. This protection provided by the mother, however, is short-lived. During the first few months of life, maternal antibody levels in the infant fall, and protection fades by about six months of age.

Passive immunity can be induced artificially when antibodies are given as a medication to a nonimmune individual. These antibodies may come from the pooled and purified blood products of immune people or from non-human immune animals, such as horses. In fact, the earliest antibody-containing preparations used against infectious diseases came from horses, sheep, and rabbits.

HOW ARE NEW DRUGS DEVELOPED?

Research chemists examine different chemicals to find out how they react with other chemicals and with living cells. When a mixture of chemicals is thought to have potential in the treatment of certain conditions, various combinations of the chemicals will be tested to see whether they might be dangerous to living things. Tests on individual cells and on animals are made before human beings are given the new drug. Many people think that drug-testing on animals is wrong, but others feel that this is the best way to make sure that drugs are safe. Trials of the drug, in which some patients are given a placebo (a drug with no active ingredients), carried out to assess the drug’s effectiveness. It is usually only after many years of testing and monitoring that the drug is released for use by doctors.

The journey will have begun in a university laboratory where researchers, with grants from the research bodies or the pharmaceutical industry, have undertaken basic research to understand the processes behind a disease, often at a cellular or molecular level. It is through better understanding of disease processes and pathways that targets for new treatments are identified. This might be a gene or protein instrumental to the disease process that a new treatment could interfere with, for example, by blocking an essential receptor.

Once a potential target has been identified, researchers will then search for a molecule or compound that acts on this target. Historically, researchers have looked to natural compounds from plants, fungi or marine animals to provide the basis for these candidate drugs but, increasingly, scientists are using knowledge gained from the study of genetics and proteins to create new molecules using computers. As many as 10,000 compounds may be considered and whittled down to just 10 to 20 that could theoretically interfere with the disease process.

The next stage is to confirm that these molecules have an effect and that they are safe. Before any molecules are given to humans, safety and efficacy tests are conducted using computerised models, cells and animals. Around half of candidates make it through this pre-clinical testing stage and these five to 10 remaining compounds are now ready to be tested in humans for the first time. In the UK, approval by the Medicines and Healthcare products Regulatory Agency (MHRA) is required before any testing in humans can occur. The company will put in a clinical trial application (CTA), which will be reviewed by medical and scientific experts, who will decide whether or not sufficient preliminary research has been conducted to allow testing in humans to go ahead.

Each year sees a couple of dozen new drugs licensed for use, but in their wake there will be tens of thousands of candidate drugs that fell by the wayside. The research and development journey of those new drugs that make it to market will have taken around 12 years and cost around £1.15bn.

WHAT CAUSES ILLNESS?

Understanding the cause of an illness can often help a doctor to bring a patient back to good health or to suggest ways to prevent the illness from recurring or affecting other people. Illness may he caused by an accident, which physically affects part of the body, or it may be brought about by tiny organisms such as bacteria and viruses. Antibiotics are used to treat bacterial infections, while antiviral drugs attack viruses. In both cases, some disease-causing organisms are resistant to drug therapy. Occasionally, the cells of the body seem to act in destructive ways for no obvious reason. This is what happens in some forms of cancer. However, researchers are finding new ways to combat disease all the time.

A complex illness contains two or more elements of illness, causal illness, injury illness and blockage illness, with a single cause. A complex illness requires a cure for each illness element.

For complex illnesses, the first cure is to address the cause.  The second cure is to heal the damage, the third to transform the negative attributes that resulted from illness and from healing. It is possible, sometimes necessary to work on elemental cures out of sequence, or at the same time. However, cures can seldom be completed out of sequence, because the prior illness is a cause, and the illness will recur.

The hierarchy is also a hierarchy of life and of health. It is also useful to view the hierarchy of illness. An illness can exist in a single cell, the simplest life form. A single cell might have an illness with a single cause that causes an injury that is healed, but leaves a blockage resulting in congestion.

An illness might exist in a bodily tissue, independent of the cells comprising the tissue.  A tissue is a layer of life above individual cells.  A tissue might have an illness because that is not a cause of cellular illnesses that leads to tissue injury, which heals and leaves a tissue blockage, resulting in congestion in the tissue.  In the same manner, a limb, or an organ, or an organ system might have a simple or compound illness.

An illness can be based in an organ, an organ system, or in the body.  This is the common view of much of today’s medical practice. It is sometimes a useful view, sometimes not so useful. The illness of the body, like that of a cell, or that of a tissue might begin with a cause, or as an injury or a blockage, caused by an internal or external factor.

An illness might also arise in the mind, or the spirit, or even the community aspects of a life entity, from internal or external causes. An illness might result in damage to the mind, or to the spirit, or to the community aspects of the patient, which when healing is not perfect, results in a negative attribute – leading to congestion, and possibly even a new illness.

WHEN WAS ANAESTHESIA FIRST USED?

Anaesthesia prevents pain signals from being received by the brain, so that the pain is not felt by the patient. Hundreds of years ago there were few ways to relieve a patient’s pain during surgery. Alcohol might be used, but it was not very effective. It was not until the nineteenth century that anaesthetic drugs began to be widely used. The first operation to be performed using a general anaesthetic was by an American surgeon, in 1842.

Anaesthesia refers to the practice of blocking the feeling of pain to allow medical and surgical procedures to be undertaken without pain.

 An ancient Italian practice was to cover a patient’s head with a wooden bowl and beat on it repeatedly until the patient lost consciousness. Presumably this method resulted in a number of side-effects the patient would not have found beneficial.

Opium and alcohol were regularly used to produce insensibility, both of which also had a number of negative side effects and neither could dull the pain completely. Few operations were possible and speed was the determinant of a successful surgeon. Patients were often tied or held down and the abdomen, chest and skull were effectively inoperable. Surgery was a last, and extremely painful, resort.

On October 16, 1846, an American dentist, William Morton, proved to the world that ether causes complete insensibility to pain during an operation performed in front of a crowd of doctors and students at the Massachusetts General Hospital. Morton instructed the patient to inhale the ether vapour and, once the patient was suitably sedated, a tumour was removed from his neck. The patient felt no pain. This demonstration transformed medical practice.

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