HPV, cervical cancer and screening: separating fact from misinformation

Few areas of women’s health attract as much misinformation as the HPV vaccine.

Online claims include that it causes infertility, has seriously harmed teenagers, has been banned in other countries or carries warnings from regulators. Some are false. Others are harder to unravel because they begin with a genuine piece of information, stripped of its context.

Questions about vaccination and cervical screening are entirely reasonable. To make sense of the answers, it helps to begin with why HPV matters.

What does HPV have to do with cervical cancer?

Human papillomavirus (HPV) is extremely common. Most people who contract it will never know they have it, and the immune system usually clears the infection naturally.

The concern is a persistent infection with certain high-risk types of HPV. These can change the cells of the cervix and, over time, those changes may develop into cervical cancer.

Around 99% of cervical cancers are linked to high-risk HPV infection.

This is what makes cervical cancer unusual: we know its principal cause and have two important ways to reduce the risk. Vaccination can protect against some of the HPV types most likely to cause cancer, while screening can detect HPV and abnormal cervical changes before cancer develops.

Is HPV the result of promiscuity?

No. This is one of the most harmful misconceptions about HPV and cervical cancer.

Because HPV is primarily transmitted through intimate sexual contact, infection is sometimes treated as evidence of multiple sexual partners or sexual irresponsibility.

It is neither.

Anyone who has been sexually active can be exposed to HPV, including someone who has had only one sexual partner. The virus can also pass through close genital skin-to-skin contact; penetrative sex is not required.

Having more sexual partners can increase the opportunity for exposure, as it does with other sexually transmitted infections. That is very different from saying that promiscuity causes HPV or cervical cancer.

HPV can also remain undetected for years, which usually makes it impossible to know when you acquired the infection or from whom. A positive result is not evidence of recent sexual activity or infidelity.

Cervical cancer is not a moral consequence of sexual behaviour.

The medical issue is whether a high-risk HPV infection persists and causes abnormal changes in cervical cells. Vaccination and screening help us reduce and manage that risk.

Stigma makes this harder. If shame or fear of judgement discourages someone from discussing HPV, being vaccinated or attending cervical screening, it becomes another barrier to care that can help prevent cervical cancer.

Why vaccinate against HPV at a young age?

The HPV vaccine is most effective before someone has been exposed to the virus, which is why vaccination programmes usually target children and young adolescents.

Because HPV is mainly transmitted through intimate sexual contact, the timing can cause confusion. Vaccination at this age is not a judgement or prediction about a child’s sexual behaviour. It allows the immune system to build protection well before exposure may occur.

Younger adolescents also develop a particularly strong immune response to the vaccine.

South Africa’s HPV vaccination programme therefore targets girls at an age when the vaccine can provide the greatest preventive benefit.

What about the risks of the vaccine?

No medicine or vaccine is completely without risk. Acknowledging that does not weaken the case for vaccination.

Common reactions include pain or swelling at the injection site, headache, fever, nausea and dizziness. Fainting can occur after injections, particularly among adolescents. Severe allergic reactions are possible, but rare.

The useful question is not whether any risk exists, but how the known risks compare with the potential benefit.

HPV vaccines have been used and monitored internationally for many years. Large safety studies and ongoing surveillance have found no evidence that the vaccine causes infertility or widespread serious illness.

The benefits are also increasingly measurable. Countries that introduced vaccination earlier have seen substantial reductions in vaccine-type HPV infections and cervical precancers. Research has also shown fewer cases of cervical cancer among women vaccinated when they were younger.

The evidence is clear: the benefits of HPV vaccination in preventing HPV-related disease and cancer substantially outweigh the known risks.

How does genuine information become misinformation?

Some claims about HPV vaccination are difficult to assess because they contain a fact but omit what that fact means.

Adverse events reported to regulators such as the US Food and Drug Administration are one example. These reports are real and form part of vaccine safety monitoring.

An event that happens after vaccination, however, was not necessarily caused by it.

When thousands or millions of people are vaccinated, some will become ill afterwards for unrelated reasons. Safety monitoring looks for patterns and asks whether a condition occurs more often than expected.

The claim that India ‘banned’ HPV vaccination after girls died follows a similar pattern. A vaccination demonstration project was suspended in 2010 after reported deaths and legitimate concerns about consent and how the project was conducted. Investigations did not establish that the vaccine caused those deaths, and India did not ban HPV vaccination as a result.

Context matters. Accurate information can still be used to support a misleading conclusion.

Does an HPV-positive result mean cancer?

No. HPV is extremely common, and most infections do not lead to cancer.

A positive high-risk HPV result means that a type associated with cervical cell changes has been detected. Further monitoring or investigation may be appropriate, but the result does not mean that you have cervical cancer.

It also cannot establish when you contracted the infection or who you contracted it from. Because HPV can remain undetected for years, a positive result should not be interpreted as evidence of recent transmission or infidelity.

If I’m vaccinated, do I still need cervical screening?

Yes. Vaccination and cervical screening do different jobs.

The vaccine helps prevent infection with some of the high-risk HPV types responsible for cervical cancer. It does not protect against every type that can cause the disease.

Cervical screening looks for high-risk HPV and/or abnormal changes in cervical cells. These changes can often be identified and managed before they progress to invasive cancer.

Being vaccinated does not remove the need for appropriate cervical screening. Feeling perfectly healthy does not either.

That is the point of screening: you do not wait for symptoms. Precancerous changes in the cervix generally cause none, and an abnormal result does not necessarily mean cancer. Screening gives us the opportunity to identify risk and intervene earlier.

Ask questions, but question the answers too.

Questioning a vaccine, a screening recommendation or any other medical intervention is reasonable.

Ask about the risks and side effects. Ask why it is recommended and what the evidence shows. Then apply the same scrutiny to information encountered online.

Was an illness reported after vaccination, or shown to have been caused by it? Did a regulator publish safety information, or warn against the vaccine? Did a country suspend a particular programme, or ban vaccination altogether?

With cervical cancer, we have an advantage that we do not have with many other cancers. Persistent infection with high-risk HPV causes almost all cases. Vaccination can reduce the likelihood of that infection, while cervical screening can identify risk and abnormal changes before they become cancer.

Neither offers a guarantee. Together, however, they give women a powerful opportunity to prevent cervical cancer or detect changes long before cancer develops.