Thailand celebrated last year when the human papillomavirus (HPV) vaccine against cervical cancer was finally added to the National List of Essential Medicines after an ongoing push. Given its cost-effectiveness, the shot was approved to be administered for free during the pilot phase, which started on Aug 1 to 400,000 fifth-grade students nationwide -- an achievement for the government and health advocates, a boon for the public.
But when a group of students at a Phitsanulok school reportedly suffered breathing difficulty after receiving a jab on the school premises earlier this month, many started to frown upon it and ask whether the shot does more harm than good. While some questioned if the respiratory complication was the shot's adverse side effect, the Department of Disease Control was quick to come out and say students actually developed mass hysteria rather than felt after-effects from the vaccine.
Since the HPV vaccine was first introduced in Thailand in 2006, many thousands of doses have been administered as a protection against cancer of the cervix, which is the fourth-leading cancer-related cause of death among Thai women after liver, lung and breast, according to data from the Ministry of Public Health's Department of Health. So far common side effects involve redness and swelling at the site of the injection that can last a few days, slight muscle pain and fever, said gynaecological oncologist Dr Panon Kasemsarn.
"The vaccine's components and volume can definitely cause pain at the injection site. But the HPV shot does not lead to other side effects like those caused by any other type of vaccine in the market," Dr Panon said.
This lines up with data from the World Health Organization (WHO), which revealed that the HPV vaccine has been administered to millions of girls and women around the world without serious side effects. Set aside the aforementioned conditions, the WHO also suggests headache and nausea as common, mild reactions to the vaccine.
"As with all vaccines, the safety of these [HPV] vaccines is monitored very carefully," wrote the WHO.
Despite all these recommendations by global healthcare authorities such as the WHO as well as many other gynaecologists and healthcare providers, there have been reports of people possibly suffering severe side effects after having the HPV vaccine including muscle weakness, postural orthostatic tachycardia syndrome, a condition in which a change from lying to standing causes an abnormally large increase in heart rate and blood pressure, as well as complex regional pain syndrome, an uncommon form of chronic pain that affects arms and legs.
But according to Dr Panon, these rare cases have been followed up and "it is hardly possible to pinpoint if they are really associated with the HPV vaccine", he said.
The HPV vaccine controversy in Japan has been in the global spotlight since 2013 after the Japanese government stopped recommending the HPV shot for schoolgirls following reports of side effects. The vaccine was actually approved in Japan in 2009. Four years later, it was recommended to schoolgirls aged from 12 to 16 by the Japanese Health, Labor and Welfare Ministry who only months later suspended its recommendation in response to complaints of side effects. The Japan Times reported that 2,945 of some 3.39 million women and girls who received the vaccine shots -- or 0.09% -- complained of health effects including headache, nausea and fatigue to loss of memory and numbness in their hands and legs.
Although in 2014 Japanese experts commented that the reported side effects were "psychosomatic reactions" triggered by the pain of the vaccine shots and related anxieties, the Japanese government has not yet revoked its order to withdraw the HPV recommendation among its citizens.
"When it comes to these HPV vaccine controversies, bear in mind that there are always two sides of the story," added Dr Panon. "People have different opinions on the vaccine because they view the issue from different angles. And there is no right or wrong."
In Thailand, the HPV vaccine has been included in the National Cancer Control Programmes as a protective shield against the HPV virus, which is responsible for almost all cases of genital warts and cervical cancer. The virus is transmitted through sexual activities which explains why the country's preventive programme targets fifth-graders thought to have not yet been involved in any sexual experiences. This is in accordance with the WHO's primary target group for HPV vaccination in most countries -- young adolescent girls, aged from 9 to 14. The shot is reported to render 90% effectiveness against cervical cancer.
Secretary-general of the Foundation for Consumers Saree Ongsomwang said now that the HPV vaccine has been offered as public welfare for Thai students, parents should be vigilant more than ever as to what they need to know about the jab, including its efficacy and possible side effects, so that they can decide for their little ones.
"We should not just look at the vaccine's benefits alone," she commented. "Rather what parents need is a comprehensive set of data before making a decision. Vaccination should be voluntary. Parents should have the right to decide if they would allow their kids to be vaccinated or not."
And as with other types of decisions made, education is paramount.
"There are many aspects to these vaccine controversies," Saree added. "We must admit that the vaccine industry does involve a lot of profit. For vaccines and medicines to benefit our people, the country needs proper and systematic monitoring, follow-up and management in terms of safety. We cannot just go to extremes without enough information and education."
The controversy over the HPV shot might be triggered by both the pro-vaccine and anti-vaccine movements or has more side stories than just medical perspectives. But Dr Panon echoed Saree's viewpoints. Education and awareness are key in making an informed decision to receive or not to receive the shot.
"If you ask medical specialists and academics, they certainly recommend the [HPV] vaccine as they consider its side effects as acceptable. These experts usually follow guidelines from international and national organisations like the WHO, the FDA, the Ministry of Public Health and the Royal Thai College of the Obstetricians and Gynaecologists and as a result, they believe the vaccine is medically proven to be effective in preventing cervical cancer.
"But as consumers and parents, it is best that they keep their eyes and ears open for information, read and listen to it carefully, talk to doctors thoroughly before making any decision. The government should also ensure people are well educated about the vaccine. Parents should pay real attention rather than just believing whatever neighbours say. There is no need to take sides because this whole issue is all about making decision based on justified information."
Human papillomavirus (HPV) causes cervical cancer, which is the fourth most-common cancer in women.
There are many different strains of HPV, the most problematic ones (high-risk types) are HPV 16 and 18. Together they are responsible for around 70-75% of cervical cancer cases globally. There are also low-risk HPV virus strains, the most common ones HPV 6 and 11 can lead to genital warts.
Two HPV vaccines are now being marketed in many countries throughout the world — a bivalent (protects against two strains, HPV 16 and 18) and a quadrivalent vaccine (protects against all four strains). Both bivalent and quadrivalent vaccines have been approved for use by Thailand's Food and Drug Administration (FDA).
For females aged below 15 at the time of the first dose, the two-dose vaccine is recommended (0, 6 months). For those above 15, they should opt for 3-dose schedule (0, 1-2, 6 months).
Patients with a history of allergies to any vaccine component should notify medical staff before receiving the HPV shot. The quadrivalent vaccine is not recommended for people with immediate hypersensitivity to yeast. The bivalent vaccine is not recommended for people with severe allergic reactions caused by latex.
Common side effects include pain, swelling, redness and itching at the injection site which is usually temporary, not severe and will disappear on its own. Fever can be found in around 10% of those receiving the shot and will also recover on its own. Other post-vaccine conditions include headache, nausea, vomiting, weakness and rashes which are mild and go away on their own.
Severe and fatal allergic reactions (anaphylaxis) are rare. Only 2.6 in 100,000 injections are found to cause anaphylaxis — the same ratio as in other vaccines.
Information from Thailand's National Cancer Control Programmes (2013-2017), the World Health Organisation (WHO) and the US's Centres for Disease Control and Prevention (CDC).
