The reporting of theoretical health risks by the media: Canadian newspaper reporting of potential blood transmission of Creutzfeldt-Jakob disease

CJD is a rare incurable neurological disorder that inevitably results in death within one to two years. It is an unusual condition as it does not occur as the consequence of a bacterium or virus but rather an infectious protein or "prion". Individuals who acquire CJD develop movement disorders, followed by a progressive dementia. In 1996, a variant form of the condition (vCJD) was described that was linked to Bovine Spongiform Encephalopathy (BSE) or Mad Cow disease. This condition differs from the classical form by affecting younger individuals and presenting with primarily psychiatric symptoms. It is suspected that vCJD develops in individuals who have eaten beef from cows affected by BSE [6].

The majority of cases of CJD likely arise from sporadic mutations in brain proteins of previously healthy individuals. In a minority of cases CJD has been shown to be transmitted by transfer of neurological tissue from individuals affected by the condition to unaffected individuals. The most frequent form of this transfer has been administration of human growth hormone derived from the pituitary glands of individuals who had died of CJD [7]. While no conclusive evidence exists of transmission of CJD via blood products, the theoretical possibility of this transmission has concerned several nations' blood systems. This has led to policy decisions to prevent blood donations from individuals with CJD or those at risk of this condition.

The media plays an important role at the interface of science and policy. One model of policy making specifically describes the media's role in the policy process as that of a key disseminator of scientific information [8]. This model describes how information is generated by researchers and then disseminated by advocacy networks and the media. This information is ultimately picked up by individuals formally involved in the policy process, such as government officials, and those informally involved, such as citizens and stakeholder groups. The interpretation of this information is influenced by the value systems of the individuals receiving the information.

The media's role as a disseminator of scientific information is particularly important in areas of risk. The mechanism by which the media present scientific information on risk to the public can influence risk perception. For example, the choice of the media to report relative as opposed to absolute risks associated with a potential harmful agent can magnify the public's perception of the risk associated with exposure to the agent [9]. However, frequent media reporting of a risk, regardless of the content of the reporting, can lead to an increased ability to recall the risk from memory. According to the "availability heuristic" this increased ability to recall a risk increases an individual's perception of the likelihood of the risk occurring [10]. This observation has led to investigations of whether the media's coverage of health risks accurately reflects the likelihood of the risks occurring [11, 12]. Findings from these studies have led to the accusation that the media exaggerate some risks and ignore others [13]. However, other analyses argue that the media in general support currently held views on risk due to their reliance on experts in reporting these risks [14]. The appropriateness of media reporting of health risks and its potential impact on policy remains a matter of debate [15].

To characterize the reporting of CJD and blood supply stories, and to determine how information on risk was reported, we conducted a content analysis of major Canadian newspapers [16]. We searched six major Canadian daily newspapers between January 1990 and December 1999 using the Canadian Business and Current Affairs, Infomart and Infoglobe databases. The selected papers included the oldest English-language national newspaper (Globe and Mail – 2002 weekly circulation of 2 085 115) [17], as well as papers representing the 5 largest cities in Canada (Montreal Gazette-999 874, Vancouver Sun-1 211 808, Calgary Herald-838 048, Ottawa Citizen-1 021 282, Toronto Star-3 337 467). These papers had the highest circulation in their respective cities with the exception of the Montreal Gazette which was the highest circulation English newspaper in its city. We searched the databases using the following key words: (CJD or Creutzfeldt) and blood. Two authors independently reviewed all retrieved articles and identified reports relating to blood transmission of Creutzfeldt-Jakob disease. Independently and in duplicate, we extracted data from these articles and categorized them under the following headings: newspaper, date, location of article, author of article, individuals cited, organizations cited, event reported, reporting of evidence, and slant of reporting. Reporting of evidence was classified under the following headings: general statement of risk, expert opinion, animal evidence, case report, and epidemiological study. All disagreements were resolved by consensus. The QSR.NUDIST qualitative software was used to analyze the data and identify patterns of reporting [18].

To determine whether news stories impacted the policy agenda and, if so, the mechanism by which this occurred, we relied on information obtained from a separate parallel policy analysis we conducted examining CJD and blood policy related decisions [19]. This analysis specifically focused on 2 CJD and blood supply decisions: a 1995 decision to withdraw blood from a donor with CJD and the 1999 decision to defer donations from individuals who had spent 6 months in the UK between 1980 and 1996 due to concerns about variant CJD. Related policy decisions were also examined. We obtained information for this analysis from a review of minutes of meetings, policy papers and other relevant documents. We supplemented this document review by conducting 32 semi-structured interviews with key informants who were involved in the policy process. During the interviews we asked individuals to describe how decision-making took place and what they believed were the key factors that influenced the decision-making process. We specifically asked individuals how external factors, such as the media, influenced the development of policy. All interviews were taped, transcribed and coded using QSR.NUDIST software. We extracted all references to the media in the interviews, both from coded text and from a text word search and identified those statements that referred to the media's role in the policy process. From this information we identified links between media reports and the development of policy.

Four of the interviews we conducted were with journalists. These interviews explored in more detail the role of journalists in reporting stories pertaining to the potential blood transmission of CJD. We asked journalists their perceptions of how the policy processes unfolded, the role of the media in the policy process, how the media should report such issues of theoretical risk and how the media obtains scientific information on issues of risk. From these interviews we developed themes that characterized the journalists' perspectives on reporting stories of this nature.

Newspapers focused on 4 major CJD and blood supply related stories. Newspaper reporting of CJD and blood supply issues began on July 11, 1995. A series of stories described the potential new threat of CJD to the Canadian blood supply as well as several withdrawals of blood obtained from donors with CJD that were carried out to protect Canadians from this risk (29% of all articles, July 1995 to November 1995). Newspaper stories later focused on the controversies surrounding whether recipients of blood from these donors should be notified of the potential risk of developing CJD (11% of all articles, September 1995 to September 1996). Beginning in December of 1998 a series of newspaper stories covered the quarantine of blood that was obtained from an American donor with a suspected variant form of CJD (13% of all articles, December 1998 to April 1999). Also in 1998 newspapers began covering stories that led to the decision to ban blood donations from individuals who had traveled to the UK for 6 months between 1980 and 1996, due to concerns that these individuals may be harbouring variant CJD (14% of all articles, August 1998 to September 1999) (Table 2).

We identified one instance in which newspaper reporting appeared to directly influence the development of policy. A July 11, 1995 newspaper story reported statements made by an American hematologist, Dr Nathan Kobrinsky, testifying at the Krever Inquiry into the Canadian blood system that CJD could be the next major threat to the Canadian blood system. Canadian Press, the national wire service, reported these statements and 4 of the 6 newspapers that we examined published the story. The newspaper stories ran headlines that referred to the emergence of a "new killer virus" [20] (Table 5). A Vancouver woman subsequently read the story and notified the Red Cross that her father, a frequent blood donor, had recently died of CJD. In response, the Red Cross voluntarily recalled all blood products that potentially contained this donor's blood.

The impact of this story on the decision to embark upon the blood withdrawal is clearly supported by transcribed reports from the Krever Inquiry [21]. In these reports the Director of the Canadian Red Cross Society, the organization that was responsible for collecting, testing and distributing blood products, made the statement:

"There was wide-spread media coverage of what Dr. Kobrinsky said. And if I remember right, it's my understanding that the daughter of the patient in Vancouver was aware of the media coverage, and because the father had been just diagnosed with this disease with this long name which nobody could forget, she was, you know --- that's why she called the centre"

The blood withdrawal triggered by the newspaper story had important consequences. It was, at the time, the largest in Canadian history, created shortages of certain blood products and was estimated to have cost $11 million.

In addressing the potential risks of classical and variant CJD blood transmission, the majority of articles (60%, 148 articles) directly stated or alluded to the fact that there was no evidence that CJD could be transmitted by the blood system. Twenty-six percent of articles (64) made reference to the potential or theoretical risk of CJD blood transmission. Articles often described the risk of transmission as follows: "There's never been a reported case of Creutzfeldt-Jakob disease being transmitted via blood transfusions or plasma products, but medical research hasn't ruled the possibility out" [22].

Most articles relied upon expert opinion when communicating information on risk of blood transmission of CJD (47 articles, 19% of total). Of these reports, the majority (40 articles) implied that CJD blood transmission was not possible. The expert opinion in 22 of these articles was from scientists or physicians affiliated with the government or a stakeholder group. In 28 articles, expert opinion was derived from independent scientists or physicians (Table 4).

Of all 245 articles, only 11% (28 articles) referred to some form of scientific study evidence. Of these 28 articles, 11 referred to animal evidence, 10 of which suggested blood transmission was possible. Twelve of the 28 references to scientific evidence referred to a single case report that suggested the possibility of blood transmission of classical CJD [23]. Only 5 of the 28 references to scientific evidence referred to epidemiological studies: one reference to epidemiological studies in general, one to a 1993 case-control study, two to a study of hemophiliacs and one reference to a cohort study of veterans [24, 25]. All references to epidemiological studies indicated a lack of evidence for classical CJD transmission via blood products.

Several themes emerged from our interviews with journalists and other individuals involved in the policy process regarding reporting of CJD and blood supply stories. A perception existed among members of the media that they may have previously failed in their responsibility to raise public awareness of the risk of blood transmission of hepatitis C and HIV. Journalists stated that this perception was partly responsible for the high degree of attention that the potential risk of CJD to the blood supply received in 1995. These views are reflected in the following statement made by one of our respondents; "Journalists felt very much in the past that they had done a disservice about playing down the risk (of transfusion transmission of hepatitis C and HIV) and so what they did was they went overboard during the Krever Inquiry".

In deciding how to report the potential blood transmission of CJD, journalists struggled with balancing their responsibility to raise awareness of risk with their responsibility to not unnecessarily alarm the public. One journalist we interviewed stated; "I think you have to be very responsible and careful when you are dealing with something that is a theoretical risk. You have to be very careful with your words because you don't want to panic people but you still want to raise awareness of these issues."

Journalists described to us the challenges in reporting scientific information on theoretical risk specifically on an unusual form of infections such as CJD. One reporter stated "The journalists we interviewed explained that the time and resource limitations they face make it difficult for them to keep abreast of important medical studies related to the stories they are covering. Expert opinion was considered to be more accessible and understandable. Journalists also stated that they would desire a closer working relationship with academics. One journalist specifically commented; "If someone in the academic field sees a story emerging that they think the media doesn't know enough about or if there is an angle we are not covering properly, I wish they'd call." However, another journalist stated that relying upon researchers can itself be problematic as they may be attempting to promote their area of research and thus sensationalize issues of risk.