Sexy sexy sex.
I mean that in the broadest possible way. I mean that in a way that any transfer of fluids is sex. I mean that in a way that doesn’t depend on a particular penis or a particular vagina. But does often depend on genitals, however they may come.
Transmission or infection can be prevented by practicing safer sex. So, take just a few seconds, then go have fun. Future you will appreciate it.
Now that we’ve established that. Lets do a quick dive into a science called epidemiology. Epidemiology is a game of numbers. Of numerators and denominators.
More specifically, epidemiology seeks to understand patterns, trends, and causes (epi trigger word) of disease in specific populations. The particular population matters a lot to an epidemiologist. So, while we may find that the colour blue is actually perceived as three shades lighter in Vancouver (probably not true) — you cannot necessarily assume the finding or pattern will persist across different populations. In, New York, blue may just be blue (probably true). So, as we go forward, and beyond the scope of this post, keep in mind that when looking at data (and health data in particular), consider to which populations the relevance of data extends, and where relevancy actually ends.
Now. Epidemiologists often talk about incidence and prevalence. Incidence or prevalence of disease, of conditions. Incidence or prevalence of a thing among other things. Oranges per grocery store. Grocery stores per city. Cities per country. All of these describe rates — so do incidence and prevalence of disease. Incidence describes the event of catching something within a period of time; where prevalence describes the total number of people with disease within a period of time. Yes, it is confusing. No, you shouldn’t worry.
So. What does this have to do with prevention and transmission? Everything. The thing that matters most is that the higher the rate of disease within your particular geography and/or population, the higher the likelihood that an individual is carrying disease. Now, there are also a hundred hundred other socio-economic factors to consider: poverty rates, public health capacity, education, access to healthcare, etc. Suffice it to say, this is why epidemiology exists. To describe the chaotic system that is the natural world — and how we all fit in.
Back to how this stuff sticks. HPV itself is the most common sexually transmitted infection out there. As mentioned above, transmission is actually much more nuanced than just plain old sex. Any sexy fluids can transmit HPV to many of the body’s mucosal membranes (inside skin. skinside.). So, vaginas, rectums, urethras, mouths and throats. And, although super uncommon, noses and eye lids too! Everyone has eyelids. Watch out.
Transmission isn’t all that difficult, as it turns out. Which is exactly the goal of the virus itself, and it does it pretty well. There is a 5–100% probability of transmission during intercourse (note: data are from penis in vagina (PIV) relationships). That is a pretty big range, but all it really means is that transmission between partners is pretty likely to happen. Most sexually active people will contract or acquire HPV in their lifetime. And, it takes around 1–2 years for our body’s immune system to kill off the infection, meaning you can transmit it to partners for 1–2 years after contracting the infection yourself. Not super fun stats, sorry. Here is a picture of otters hugging.
Globally, we want to stop HPV from either having the opportunity to transmit between people (physical barriers), or to not worry about transmission by stoping it from being able to multiply within the body (immunological barriers). Physical barriers are pretty effective, but require a fair bit of rigour to work as well as possible. Dental dams, condoms, condoms cut into dental dams, gloves, etc. Beyond appropriate use of barrier methods during sex itself, people need to be aware of what they touch. Watch your hands, wash your hands. General fluid awareness is key.
Immunologic barriers depend entirely on your immune system protecting you because of a vaccine. Current vaccines are extremely safe, and extremely effective at preventing the strains of HPV that are most likely to cause cervical cancer (16 and 18, and some others sometimes). However, they do not prevent against all forms of HPV. There are close to 100 strains of HPV, and growing. Because: biology. One of the really weird things about vaccination, is it actually changes the entire HPV ecosystem within your community. Because those particular versions of the virus (16 and 18) are unable to productively infect people, other versions of the virus have the opportunity to thrive. An important point to note is that people do still need to get screened after vaccination. Repeat: screening is still important. By continuing to screen regularly you prevent the risk of unknowingly developing lesions or cervical cancers from those less harmful version of the virus. But. HPV can be beat. It can be eradicated. Although difficult, it is all very possible.
Developing permanent solutions to HPV infection, such as vaccination is a complex process and takes a fair bit of time. Ultimately, both forms of protection (physical and immunological) are necessary to control HPV. Public health is our collective opportunity to keep everyone safe. Everyone’s health matters when it comes to keeping us all happy, and healthy.
Keep it up.
Matthew German. MSc, Molecular Virology.
Matthew is currently at BlueDot, a B-Corporation that develops public health and consumer technologies to prevent the spread of infectious disease through global epidemic prediction, preparedness and response. On the side, Matthew is also exploring how we can change the way we interact with technology to align with our biology and psychology, through his project Veni.
Izabella Kaczmarek. MPH candidate.
Izabella is responsible for education and community coordination at Eve Medical, a social venture that is extending women’s health screening beyond the clinic into the privacy and comfort of women’s homes. Motivated by the 500,000 cases of cervical cancer that occur worldwide each year, Eve Medical developed and launched Canada’s first Eve Kit, the do-it-yourself at-home HPV screening service. On the side, Izabella is completing her Master of Public Health at the University of Waterloo with particular interests in addressing inequalities within the Canadian health system.