HPV VACCINE

Context

How does vaccination against an infection protect against cancer?

• Cervical cancer continues to be one of the only vaccine-preventable cancers.
• Almost all cervical cancers are found in women who have a history of HPV infection.
• Over 80 per cent of women have an HPV infection in their lifetime and almost all of them can clear it.
• But in some people, some high-risk types of HPV persist and lead to cervical cancer.

• The best way to prevent cancer is to prevent an infection in the first place and that is what HPV vaccines do.
• There are two to four types of HPV that lead to almost 70 to 80 per cent of all cervical cancers and vaccines prevent these infections.
• Since the virus is sexually transmitted, it has to be given to teenage girls before they are sexually active.
• Once an infection happens, the vaccine cannot clear it out. Hence, the effectiveness of the vaccine keeps dropping with age.

How will the new vaccine help?

• The problem then is that universal immunisation of all teenage girls becomes an expensive proposition.
• The Delhi government 2016 decided to start immunising schoolgirls at the Delhi State Cancer Institute (DSCI).

• Now, Cervarix is not readily available in India, so we had to start using the other one, which is costlier.
• started the tendering process for a fresh batch of vaccines, and we realised that the India-made vaccine will soon be available.
• This is the role the new vaccine will play.
• It will make it cheaper and more cost-effective for governments to give the shot under public health programmes.
• It will become a part of the national programme as well.

 Impact of a universal vaccination programme

• The impact will be tremendous if we can vaccinate 90 per cent of teenage girls.
• It will drastically bring down the incidence and deaths caused by cervical cancer in India, which is more important because the country contributes to about a fourth of the global mortality from Cervical cancer.
• India sees about 1.2 lakh cervical cancer cases a year and around 67, 000 deaths a year.
• Even without vaccination, incidence and deaths due to cervical cancers are declining in India and globally.
• It has moved down to the second position, after breast cancer, from being the biggest killer among cancers in women in India.
• The vaccine wipes out more than two-thirds of the cases and deaths that are caused by the four most common types of HPV.

Effects of vaccination

• There are previous discussions the government had about including it as a part of the National immunisation effort.
• It did not happen because of unfortunate incidents in Andhra Pradesh and Gujarat.
• There were procedural lapses in the trial there, which led to the government going on the back foot. Globally HPV vaccine is very safe and effective.
• There is a minuscule chance that a person has an adverse effect, which is true of any vaccine.

Who needs to get the vaccine?

• The vaccine can only prevent infections so it needs to be given to girl children starting at the age of 11 or 12 years, up to 16 years.
• Even after that, the vaccine can be given.

For those who have crossed that age, how can cervical cancer be prevented? 

• For those who are past the age of HPV vaccination, regular screening is the best way to keep an eye out for whether they have cervical cancer.
• Earlier, we used to do a pap smear (a procedure where a small brush is used to remove cells from the cervix to be studied under the microscope). we now perform HIV tests.
• The sample is collected similarly but it looks for the high-risk types of HPV in the cells.
• This test should be done starting two to three years after sexual activity begins, then every five years until the age of 65.