March, 15th 2020
This week I am going to be discussing a sexually transmitted infection (STI), its vaccine, and its link to cervical cancer. Specifically, I will be diving into the Human Papillomavirus, or HPV. In my Microbiology class we discussed a little bit about this infection and how it is highly linked to the cause of cervical cancer. Prior, I did not know that a virus could be so highly linked as the causing agent to cancer, which is why I wanted to do more research. I hope you all enjoy my discussion about HPV, its vaccine, and link to cervical cancer as I think it is very important and interesting.
Human Papillomavirus (HPV)
First off, I will discuss what this sexually transmitted infection is. The Human Papillomavirus, or HPV, is the most common sexually transmitted infection (STI). My Microbiology teacher, Dr. Cramer, stated that almost everyone will have been exposed to this virus by the time they are 80 years old. This virus is transmitted though sexual contact, meaning it is spread during anal, vaginal, or oral sex. Additionally, this virus can be transmitted vertically, from a mother to its baby. Humans are the only reservoir for this virus, thus HPV can only grow in humans and can only infect humans. This means it is possible for HPV to be eradicated off the face of the earth because there are effective vaccines out there.
Further, HPV is a double stranded DNA-virus, with over 100 types of strains. Each strain differs in the type of wart that they cause. On a molecular level, each strain has viral spikes that bind to specific receptors found on different tissues throughout the body. The most common place for these warts to appear is on the genitalia. Over 40 strains of HPV cause genital warts. However I think it is very important for me to note that not everyone that is infected with HPV will have warts, meaning they are asymptomatic. More than likely, someone infected with this virus will be asymptomatic. I think it is very important for me to note that just because you are asymptomatic (not showing a visible symptoms, in this case warts) that does not mean you are not contagious. You can still shed this virus to you partner, or baby even if you have no warts. This is why it is very salient that if you are sexually active to be vaccinated, use protection, and get tested.
HPV and Cervical Cancer
HPV has been shown to become latent in some infected hosts. When this infection resurges, it can cause abnormal tissue growth, aka cancer. Strains that are known to cause cancer are called “high-risk” strains. HPV causes approximately 5% of all cancers worldwide, including: penile, throat, cervical, pharyngeal, head and neck cancers. Scientists and researchers estimate that of the 100+ strains, there are only about 12 to 14 “high-risk strains”. Further, stains 16 and 18 are responsible for 70% of all cervical cancers, and also cause the majority of pharyngeal, penile, and vaginal cancers. My Microbiology teacher, Dr. Cramer, additionally noted that including strain 16 and 18, strains 31 and 45 also contribute to a high percentage of cervical cancers. Now, you are probably wondering, as was I, what makes these strains “high-risk”? These strains have oncogenes, which means they contain genes that give the virus the ability to make tumors. These genes allow the virus to cause abnormal tissue growth (tumors). This makes these strains more lethal and infectious.
In total, 99% of all cervical cancers in the world are caused by HPV. When I read that during my researching, I was shocked! I think it is crazy how this one virus is responsible for basically all cervical cancers. This also gave me a lot of hope. Because this virus is responsible for almost all cervical cancers and there is an effective vaccine, it is possible for cervical cancer to be eradicated off the face of the earth. To me, that is amazing as many lives are effected by this cancer and the other cancers linked to this disease. I really hope to see cervical cancer eradicated off the face of the earth within the next 10 years.
HPV Vaccine
I have mentioned a couple times through this post about the effective HPV vaccine, and I will now discuss it. This vaccine contains viral like particles (VLP), which is when scientists get the viral capsids to assemble but without having genetic material inside. Meaning, there is no DNA inside the viral head. Thus, there is no “instruction sheet” inside and the virus cannot cause any harm to the host. However, the body’s immune system will be able to create an immune response. The only approved vaccine in the United States is Gardasil, and it is recommended to be given to kids between the ages of 12 and 14. Research has shown that this is when the most effective immune response is made. One reason this vaccine is effective is that research has concluded that the prevalence of cervical cancers has decreased in women that were vaccinated, compared to those who were not.
However, many people are rebelling against this vaccine. There are various reasons why, but the most prominent is that it will promote ‘sexual promiscuity’ in those vaccinated. In response, some researchers conducted a large study that disproved this fear, yet many do not trust it. I think that it is crazy to me that parents would not vaccinate their kids with this vaccine. If you have a daughter, this would give them a 99% chance of not developing cervical cancer, as HPV is responsible for 99% of cervical cancers. As well for both one’s daughters and sons, this vaccine would reduce their chance of developing many other types of cancers mentioned previosly. I don’t know about you, but to me, that is protection I would want to give to my children. Cancer is not something I want anyone, let alone my children, too suffer from. I hope in the coming years the stigma around this vaccine and others goes away. Vaccines are important in the overall health of our society and are a great advancement of modern science that many people are not taking advantage of.
I hope you all enjoyed this weeks blog post and that you learned more about HPV, and understand the importance of its vaccine. This virus is linked to many cancers that impact many in our country and others around the world. I wish that with this new found knowledge you educate those around you and encourage those with young kids to get this vaccine. Further, I pray that you are all staying safe during this pandemic. Please please please practice social distancing, self-quarantine as much as possible, and WASH YOUR HANDS!
Thanks again, and look out for my next blog post 🙂
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