Saturday 12 December 2020

What have vaccines done for us?

 As the world awaits the imminent arrival of one — or several — COVID-19 vaccines, many people may wonder how important vaccines actually are to safeguarding public health. In this feature, we answer that question by looking at what vaccines have done for us throughout history.

 

Researchers who have looked at trends of vaccine acceptance around the world have found that, overall, people’s trust in vaccine safety and effectiveness has been on the rise over the past few years.

However, they have also expressed concern that the race for a COVID-19 vaccine may have triggered more hesitancy among certain groups.

Speaking at this year’s WIRED Health:Tech conference, Prof. Heidi Larson, from the London School of Hygiene & Tropical Medicine, in the United Kingdom, noted that “Because of the hyper-uncertainty and the whole environment of trust and distrust around the COVID vaccine, there are groups that have gotten together to resist” upcoming vaccination.

Many may now be wondering why researchers are so keen on vaccines — and whether vaccines have really achieved much for public health.

So, in this Special Feature, we look at some key moments in vaccine history and how vaccines have revolutionized public healthcare.

The ancient practice of ‘variolation’

Vaccines work by exposing the immune system to a very small amount of a virus or “information” about a virus — enough to “teach” it to recognize and react to that pathogen.

The idea of exposing the body to a virus in a controlled way to “train” it to prevent infection is by no means a modern conception.

Already in the 1500s, Chinese and Indian physicians practiced inoculation against the variola virus, which causes smallpox.

Some accounts from China in the 1600s suggest that doctors attempted the inoculation by grinding up smallpox scabs and blowing them into the patient’s nose through a silver tube.

In Europe, inoculation against smallpox, a process known as “variolation,” was introduced and popularized by Lady Mary Wortley Montagu in the early 18th century.

Lady Wortley Montagu was the wife of the British ambassador to the Ottoman Empire. From 1716–1718 she travelled across Europe to Constantinople, present-day İstanbul, where she learned about variolation.

She was so impressed by the evidence of its effectiveness that she submitted her own son for inoculation against the smallpox virus while in Constantinople and continued to advocate for the procedure on her return to Britain.

In a letter to a friend, Lady Wortley Montagu praised the procedure:

“The small-pox, so fatal, and so general amongst us, is here entirely harmless by the invention of ingrafting, which is the term [that the Ottomans] give it. There is a set of old women who make it their business to perform the operation every autumn. […] Every year, thousands undergo this operation… There is no example of anyone that has died in it; and you may believe I am well satisfied of the safety of the experiment.”

The eradication of smallpox

The word “vaccine” entered circulation soon after, when British physician Edward Jenner started experimenting with different ways of inoculating against variola.

In 1796, Jenner discovered that exposing people to small quantities of the cowpox virus, called “vaccinia” or the “vaccine virus,” was safer than exposing them to the variola virus that infects humans. The cowpox virus was also effective in preventing smallpox.

Thus, inoculation against the “vaccine virus” eventually became the umbrella term that we use today: vaccination.

This discovery was truly revolutionary for public healthcare worldwide, given the disastrous effects that smallpox had been having for centuries.

The World Health Organization (WHO) call smallpox “one of the most devastating diseases known to humanity,” as it caused millions of deaths worldwide over some 3,000 years.

Smallpox was officially eradicated in 1980, thanks to consistent global programs of vaccination. On May 8 of that year, the 33rd World Health Assembly made the historical announcement: “The world and all its peoples have won freedom from smallpox.”

According to the WHO, in the 20th century alone, smallpox ended the lives of around 300 million people.


Source: Medical News Today

 

1 comment:

  1. My husband was diagnosed with early onset Parkinson's disease at 57.his symptoms were shuffling of feet,slurred speech, low volume speech, degradation of hand writing, horrible driving skills, right arm held at 45 degree angle, things were tough for me, but now he finally free from the disease with the help of total cure ultimate health home, he now walks properly and all symptoms has reversed, he had trouble with balance especially at night, getting into the shower and exiting it is difficult,getting into bed is also another thing he finds impossible.we had to find a better solution for his condition which has really helped him a lot,the biggest helped we had was ultimatehealthhome they walked us through the proper steps,am highly recommended this ultimatehealthhome@gmail.com to anyone who needs help.

    ReplyDelete