Public health specialist and the Head of the Human Papillomavirus Programme at Gavi, the Vaccine Alliance, Dr. Emily Kobayashi, talks to LARA ADEJORO about the safety and efficacy of the human papillomavirus vaccine
Can you provide an overview of the human papillomavirus and the diseases it can cause?
Human papillomavirus is the name of a very common group of viruses and they have been associated with several different illnesses, including genital warts as well as cancers, including cervical, anal, vaginal, vulvar, penile, and throat cancers.
How does cervical cancer impact Nigerian women?
Cervical cancer is the cancer of the cervix. It tends to affect women aged 35 to 55. It is a very painful and difficult cancer. HPV infects cells in the cervix, which is the lower part of the womb, and changes the way that they communicate with each other and the way they replicate; in some people the infected cells multiply in an uncontrolled manner, leading to cancer. To be effectively treated, it requires a combination of medications, treatment with radiotherapy, and surgery, and it is often fatal. It is estimated that 8,000 Nigerian women die yearly and it is the second most common cancer in women in Nigeria. It is a very common cancer; it is a horrible condition. I am inspired by the survival of cervical cancer in Nigerian women who share their stories and their struggles and we have to prevent this illness. With the HPV vaccine becoming available, everybody has the opportunity to prevent this illness in the future.
What is the significance of the HPV vaccine in preventing HPV-related diseases?
The HPV vaccine has been shown to be 90 per cent effective in preventing cervical cancer, and this also has a herd immunity effect, which means that even people who have not been vaccinated can be protected by the fact that others have been vaccinated. In countries that have introduced the HPV vaccine, what they have seen is that for the girls and boys who have received the vaccine, the rate of HPV has gone down to definitely 90 per cent or more, and what they have also seen is that the rate of HPV in people of the same age who did not receive the vaccine has gone down by 60 per cent or 70 per cent; that is the protective effect of herd immunity.
How does the HPV vaccine protect against HPV?
The HPV vaccine works by stimulating the body’s immune system to produce antibodies against the HPV. So when a person receives the vaccine, the person’s immune system identifies the viral proteins in the vaccine and produces a response that protects against HPV infections.
How has the public perception of the HPV vaccine evolved over the years, and what are the key factors influencing its acceptance and use?
The important thing to understand is that the HPV vaccine is widely used around the world. It was introduced in 2006, and over 125 countries have adopted it and delivered it routinely in the health systems, and over time, there have been different rumours, myths, and misconceptions that have been associated with the vaccine, but the evidence that we have is that the vaccine is safe, it is effective and it is preventing HPV, and associated illnesses.
What age groups are recommended for receiving the HPV vaccine, and why is the timing of vaccination important?
Evidence has shown us that the vaccine is most effective when it is delivered before sexual initiation and before exposure to the HPV. So, the age group that is recommended is nine to 14 and the focus is on girls because of the
protective effect against cervical cancer, which is a very common cancer. Cervical cancer is the second most common cancer among Nigerian women and the second most common cancer death among women between 15 and 44 years of age.
Are you also considering targeting those above the age of 14, especially those who cannot afford it?
The nine-to-14 age range is recommended by the World Health Organization, so that is what Gavi supports. Governments in other places have chosen to vaccinate a wider age range depending on their situations and the government of Nigeria is focusing on this high-impact group. People of older ages are also eligible to receive the vaccine if they would like to access it through the private sector, but right now we are focusing on the girls aged nine to 14 because of the WHO recommendation.
Nigeria approved the Gardasil vaccine. Can you explain the differences among the various HPV vaccines available?
The WHO has prequalified three vaccines: the Gardasil, the Cervarix, and the Cecolin. The three vaccines are of high quality and protect against the types of HPV that cause cervical cancer. The Gardasil vaccine is produced by Merck, and it covers four types of HPV – two types of HPV that are associated with genital warts, and two types of HPV that are associated with cervical cancer.
How effective is the single dose of the vaccine approved by the Federal Government for the girls against HPV?
In 2022, the WHO convened its Strategic Advisory Group of Experts on Immunization and they reviewed some clinical studies, and what they found
from the studies is very strong evidence that a single-dose vaccine confers over 95 per cent of protection. With this evidence, they said countries can choose either a single or two-dose regimen and be assured of the protection of girls who receive the single dose.
Was the vaccine provided to Nigeria for free or was it subsidised?
The vaccine is partially co-financed by the government of Nigeria and it is based on Gavi’s funding guidelines and policies, so the government of Nigeria when they applied to Gavi for support, they accepted to pay their portion of co-financing the vaccine. Gavi has been a long-standing partner of Nigeria having worked together for over 20 years to improve access to vaccines for millions of the most vulnerable children. We have made tremendous progress together, and we are happy with the progress and achievements. The partnership has fostered significant progress towards increasing immunization coverage, reducing the number of zero-dose children, and working towards a sustainable immunization programme in Nigeria.
What are the most common misconceptions, myths, or concerns that people have about the HPV vaccine, and how can healthcare providers address them?
it is safe, effective, and protects people against cervical cancer. The vaccine has been in use since 2006. Every country has a modeling system to pick up any ill effect from the vaccine, and looking at data for almost two decades from the HPV vaccine, there has been no sign of any kind of serious adverse events associated with this vaccine, and that data is reviewed by the WHO, independent experts and it is assessed by national health authorities around the world. So, if there was a serious effect associated with the vaccine, by now, we would know. There is misinformation out there; there are people who are making claims but those claims are not based on science. The claim that the vaccine causes infertility in women is not true; no data or evidence suggests that any vaccine causes infertility in women or reproductive problems. The vaccine has been given to more than 270 million people worldwide since 2006, and scientists have continuously monitored the vaccine roll-outs.
Are there any side effects associated with taking the vaccine and how concerned should people get if the side effects occur?
The side effects that are known to be associated with the injection are pain in the injection site, swelling, or a small fever and we do not see a large number of these effects. The vaccination team travels with the vaccine kit so they are prepared to respond if there is any reaction.
Have there been no adverse effects recorded so far?
I cannot say there is no adverse effect but what the systems do is that they look over time to see if there is any signal from the data we get that the vaccine is causing higher rates of effects than we expect, one thing we understand is that if something happens after you receive a vaccine, it is called
an adverse effect. For example, you could get the vaccine, and you walk on the street and you are hit by a car, and you break your leg, we call that an adverse effect following the immunisation because in time, it followed the immunisation. So, we have to record those incidents and see if it is causing broken legs or not. This is in the public health picture to see if the vaccine routinely causes problems or effects that are concerning.
There are areas in the country that are hard to reach because of insecurity concerns. How do you intend to access them?
In each state associated with the launch of this vaccine, they are making their plans about how they are going to reach different communities with the vaccine. So, if they have insecure areas in that state, they will make plans about how to reach them and make sure that the vaccine team is safe and how to communicate with the community on how they can help them to accept the vaccine.
Are there any emerging trends or developments in HPV vaccination, such as new formulations, recommendations, or potential changes in the vaccine schedule?
The biggest one was the recommendation we got in 2022 on the single-dose vaccination.
How does the HPV vaccine impact public health, including the reduction of cervical cancer and other HPV-related diseases?
In 2019, the WHO established the Cervical Cancer Elimination Initiative, and the initiative has three pillars. The first pillar is vaccination, the second is screening, and the third is treatment. They developed a model to see what it would take to eliminate cervical cancer as a public health threat. So, they said we need 90 per cent coverage of the HPV vaccine to eliminate cervical cancer as a public health threat.
What strategies or programmes are in place to increase awareness and access to the HPV vaccine, especially among underserved populations?
The state-based committees that have been planning for the launch of the vaccine have been working closely with organizations, and those organizations have been educating (people) in their communities, creating jingles in local languages, they have been doing brochures, going on school visits, and educating town criers, and doing their arrays of activities based on their community needs and possible interventions on social media, and addressing misconception and misinformation as they come up.
Can you share insights on the role of healthcare providers in promoting and administering the HPV vaccine to patients?
The vaccination is only done by trained and certified healthcare providers. They should educate Nigerians about the importance of the vaccine, and potential side effects and plan the team to do the vaccination. Planning is a very crucial role.
How do you see the future of the vaccination and what challenges or opportunities lie ahead in achieving higher vaccination rates?
This is a long-term commitment. It is not something we do in a year and solve the cervical cancer problem. Every year, we have to think about nine-year-old girls and vaccinate them. Part of what that means is that health facilities need to go to schools because that is where we find most of our nine-year-old girls and in delivering the vaccine, it is possible that they can deliver other health interventions like nutrition, deworming, and screening for health conditions. I think that is what we may see in the future. As the HPV vaccine is delivered, other health interventions can also reach the children based on what they need at their age.
What research is currently underway regarding the HPV vaccine, and what potential breakthroughs or advancements can we anticipate in this field?
There is research about how best to deliver the vaccine and create uptake and there is research on future versions of the vaccine. There is some research to understand the role of the vaccine in
protecting people living with HIV because those people have higher rates of cancer, including cervical cancer. One thing about HPV is that the more we learn, the more we see the impact of the vaccine and how it is protecting against other types of cancers. So, it is exciting to learn as we do more research.
What advice would you give to parents or guardians who are considering the HPV vaccine for their children and to those who have concerns about the vaccine?
The Coordinating Minister of Health and Social Welfare, Prof Ali Pate, shared that all four of his daughters have been vaccinated against HPV. So, many parents in Nigeria are eager for the vaccine and have chosen to get the vaccine so they are confident to say it is the right choice to make for their children. Every parent chooses their family, and this is a very strong choice and opportunity to take a few seconds to protect your daughter’s life and the woman that she will become.