By Helen Petousis Harris 13/11/2017


The perception of risk is greatly influenced by the media and related to the relationship between hazard and outrage, or Risk = Hazard + Outrage (Sanderman).

Basically, the risks that can kill you are often not the risks that get you all alarmed. I am a bit scared of things with at least six legs but genes dictate it will probably be good old cardiovascular disease that carries me off even though my amygdala does not grasp this.

When the media do a story about adverse events, people can experience fear disproportionate to the actual hazard. An extremely rare or an almost non-existent speck of a risk morphs into an elephant. Another observation is that the reporting rate of adverse events to the authorities goes up. This phenomena is also observed when new vaccines are introduced. Does this reporting reflect actual rates of adverse events? Mass psychogenic illness?  bandwagoning? Or simply a stimulation of reporting?

Image from the American Public Health Association. https://www.apha.org/topics-and-issues/vaccines

 

Note: Spontaneous reports of adverse events following immunisation are not necessarily caused by a vaccine. Vaccine safety is determined via other means.

A new study published in Vaccine used NZ data to look at the patterns of news coverage about adverse events, internet searches, and reporting of adverse events to the pharmacovigilance monitoring people that were associated with the HPV vaccine Gardasil. It found (surprise surprise) that after a media story people hit the Google keys. This was followed by spikes in reports to the Centre for Adverse Reaction Monitoring. However, the reports were not related to the number of doses of vaccine administered.

The Google Trends search terms in the study focused on Gardasil, the side effects of Gardasil, and deaths attributed to the Gardasil vaccine – the latter being a highly popular myth circulating in cyberspace.

The study did not assess the actual content of the news stories, although it is fairly well established that negative information appearing in the news probably increases public uncertainly about vaccines. Here is a study about the social amplification of risk, and another about HPV reporting and adverse event reports.

I happen to have to hand the content of the media reports for the last 5-years. Going for the dramatic I picked a media event that reported Gardasil had left girls in wheelchairs (Note: A huge body of evidence shows no increased risk for such events after Gardasil!). The article appeared on the NZ television 3 network 3D show at prime time on the 9th Nov 2015. On this occasion there had been active refusal by the producer to interview a range of experts on the safety of the vaccine and a token gesture made to a Ministry Official. I know there was an active refusal to provide scientific evidence and I have a paper trail to prove it. Just saying.

Anyway, I used Google Trends to find the searches conducted from NZ with the search term ‘Gardasil’. I restricted the time to a five-month period. There is nice blip that occurs on the 9th of November (I pulled the CSV file to verify the exact day).

New Zealand Google searches for ‘Gardasil’ between 1 Oct 2015 and 29 Feb 2016

I changed the search term to ‘HPV’ and the pattern is quite different. In this case the three highest number of searches occur on the 24 Oct 15 (94), 4th Feb (100), and the 15 Feb 16 (92).

New Zealand Google searches for ‘HPV’ between 1 Oct 2015 and 28 Feb 2016

On the 15 Feb there was a news article about the anti-vaccination letter sent to around 2500 schools.

However, a search for news items mentioning HPV for around the 24th of October and the 4th of Feb did not return anything in the mainstream media. Given the time of year is possible the Feb searches were stimulated by the beginning of the school year and the issuing of consent forms for HPV vaccination. Alternatively, research has indicated that once stimulated by the media the interest can continue to flourish on the internet. There does not appear to be a trend to increasing searches for HPV.

All very interesting!

I guess the big question is does any of this matter, in other words does this affect coverage?

The answer is yes it is important and it probably affects confidence, if not coverage. Studies have shown that people who delay or refuse vaccines are more likely to have visited Dr Google.

There are also many historical examples of media affecting vaccine coverage, particularly pre-internet, where distribution of negative media/press campaign in defined geographical areas resulted in a change in vaccine uptake and outbreaks, phenomena not observed in areas that did not receive the negative media.

This year the rates for HPV vaccination are up. In fact, I would move the performance from C/C+ into the solid ‘B’ range. The boys get a ‘B+’. So does this mean that the activity in the media and the internet are not having an effect?

While I have no empirical evidence either way, what seems to me to be the elephant in the room is that given HPV is one of the most effective and one of the safest vaccines ever developed why are 30% still unvaccinated? Until we can get into the ‘A’ range I think we need to continue to examine the issues. Media reporting and internet searches are but one important component.