The human papilloma virus (HPV) vaccination programme in adolescent girls has led to a dramatic fall in the number of young women carrying the infection which can cause cervical cancer in England, a study published online in the Journal of Infectious Diseases has shown
The HPV 16/18 types, which cause the majority of cervical cancer cases, decreased by 86% in women aged 16‐21 who were eligible for the vaccination as adolescents between 2010 and 2016, the study found.
The researchers tested 15459 vulva‐vaginal swab specimens from 16 to 24‐year‐old women attending for chlamydia screening between 2010 and 2016 for HPV DNA, and then they used mathematical models to compare prevalence of the different HPV types over time and according to whether the women had received the HPV vaccine.
They found that eight years after the introduction of a national HPV vaccination programme, substantial declines have occurred in HPV16/18 and HPV31/33/45 – the five HPV types which cause around 90% of cervical cancer cases.
Prevalence of HPV16/18 decreased from 8.2% to 1.6% in 16–18 year olds between 2010/2011 and from 14.0% to 1.6% in 19–21 year olds. Prevalence of HPV31/33/45 fell from 6.5% to 0.6% in 16–18 year olds and from 8.6% to 2.6% for 19–21 year olds over the same time period.
The HPV vaccination programme was first introduced in 2008, and over 80% of girls aged 15‐24 have now been vaccinated in the UK. The vaccine is available through the NHS to girls from the age of 12 up to their 18th birthday. The programme is delivered through schools to girls in years 8 and 9, but if girls miss out on the two‐dose vaccine, they can request it from their GP surgery.
The study found that the vaccine was less effective in girls who receive it later through the catch up programme, and this was probably due to an increased likelihood of prior exposure to the virus through sexual activity, the researchers said.
“In years to come we can expect to see significant decreases in cervical cancer”
Mary Ramsay, Head of Immunisations, Public Health England
The HPV vaccination programme uses the bivalent HPV vaccine (Cervarix), which protects against HPV16 and HPV18 types. The HPV31, HPV33 and HPV45 types are not included, but evidence has suggested that the vaccine offers some cross‐protection to unvaccinated women against related HPV types.
Public Health England said that the HPV vaccination programme has also led to a marked decline in genital wart diagnoses. The number of genital wart diagnoses in sexual health clinics fell in girls aged 15‐17 by 89%, and in boys of the same age by 70%, between 2009 and 2017 as a result of herd immunity. Genital warts are mostly commonly caused by low risk HPV types 6 and 11.
Mary Ramsay, Head of Immunisations, Public Health England, said: “These results are very promising and mean that in years to come we can expect to see significant decreases in cervical cancer, which is currently one of the biggest causes of cancer in women under 35.”
She added that the study was a reminder of “how important it is to keep vaccination rates high to reduce the spread of this preventable infection”.
Robert Music, Chief Executive, Jo’s Cervical Cancer Trust: “One day we hope to see cervical cancer become a disease of the past and it is only through high vaccination rates that we will get there. For women who have had the vaccine, it is important to remember it does not offer full protection against cervical cancer so attending cervical screening when invited is still important.”
Mesher, D., Panwar, K., Thomas, S.L., Edmundson, C., Hong Choi, Y., Beddows, S., Soldan, K. (2018) The Impact of the National HPV Vaccination Program in England Using the Bivalent HPV Vaccine: Surveillance of Type-Specific HPV in Young Females, 2010–2016. The Journal of Infectious Diseases, jiy249, https://doi.org/10.1093/infdis/jiy249