If you want to see the power of vaccines, look no further than the human papillomavirus (HPV) jab. A new study has found that the rolling out of HPV immunizations in Scotland has resulted in tumbling rates of cervical disease, which can lead to cancer.
In 2008, the UK introduced a nationwide vaccination program where all girls aged 12 to 13 were immunized against two of the most troublesome strains of the human papillomavirus, HPV 16 and HPV 18, which are known to cause cancer in both women and men.
The success of the vaccine program is already proving to be remarkable. As reported in the British Medical Journal, the number of women with the most severe form of pre-cancerous cells in their cervix has fallen by up to 89 percent in a little over a decade.
In the researchers' words, the HPV vaccine has directly led to “a dramatic reduction” in cervical disease. The study did not look at how this will translate into rates of cervical cancer. However, the researchers believe it "should greatly reduce the incidence of cervical cancer."
A team of researchers from multiple Scottish universities analyzed the medical records of 138,692 women in Scotland. They reached their findings by comparing rates of pre-cancerous cells in their cervix, known as cervical intraepithelial neoplasia, between unvaccinated women born in 1988 and vaccinated women born in 1995 and 1996.
Interestingly, the study also showed that even unvaccinated women were reaping the benefits and reporting a significant drop in the levels of disease. This is an effect known as herd protection or herd immunity, where unvaccinated people are effectively protected from a contagious disease if a good chunk of the population is vaccinated. The disease is unable to spread fast enough since it encounters too many vaccinated individuals and gets roadblocked.
There are more than 100 different types of HPV and it’s incredibly common. According to the US CDC, 79 million Americans are currently infected with HPV. They also state ”almost every person who is sexually active will get HPV at some time in their life if they don’t get the HPV vaccine.” Most strains are relatively harmless, causing mild (if not irritating) symptoms like warts. Nevertheless, at least 14 types of HPV are known to be cancer-causing. It’s estimated that HPV 16 and HPV 18 cause 70 percent of cervical carcinoma, the fourth most common cancer in women.
This is just one of the many success stories of the HPV vaccination across the world. Australia is well on its way to becoming the first country in the world to eradicate cervical cancer thanks to their comprehensive vaccine program. Wider afield, computer modeling suggests cancer will totally be eradicated in 149 out of 181 countries by 2100 if current rates of progress continue.
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