“With fever it’s the real flu I would say”: laypersons’ perception of common cold and influenza and their differences - a qualitative study in Austria, Belgium and Croatia

The common cold is an acute infection of the upper respiratory tract, and is recognized worldwide as the most common reason for illness [1‐5]. Symptoms are caused by more than 100 different viruses [6] including rhinoviruses, adenoviruses or parainfluenzaviruses [7, 8]. Common colds are self-limited and typically resolve within ten days. Secondary bacterial infections are less common: a study by Lingard et al. showed that secondary bacterial infections occurred in only about 8% of patients [9]. Symptoms can include coryza, cough, sore throat, headache, fever, and myalgia. Treatments are typically targeted towards symptomatic relief [3‐5]. In contrast, influenza is caused by influenza viruses and is much more often linked to secondary bacterial infections, such as bacterial pneumonia, though, influenza is normally also observed to be a self-limiting disease with a two to three week duration. Complications of influenza can include myocarditis, or otherwise worsening of existing chronic pulmonary or cardiopulmonary diseases. The number of worldwide cases of severe illness caused by influenza each year is estimated to be in the range of three to five million, and among this there occur about 250,000 to 500,000 deaths [10]. High risk groups include those older than 65 years as well as children under five [11]. Influenza is manly recognized as starting with onset of a sudden high fever, whereas a common cold more commonly begins with coryza or a sore throat [2, 11]. Although from a microbiological point of view the two diseases are clearly different from each other as distinct viruses are involved [2, 6, 12], it may be difficult to differentiate the diseases for lay persons because they share several symptoms such as fever, cough, or limb ache. This overlap has been observed to increase the risk of confusion not only in lay persons but also in clinicians [2, 6, 13]. In contrast to previous publications which are dealing either with common cold or influenza [1, 6, 12, 25], there have been few publications about the clinical differentiation between common cold and influenza [2, 13] with very little research done on peoples’ perceptions about them. Public health and primary care studies have repeatedly shown that strategies for the improvement of the health of a population essentially rely on the inclusion of experiences and perceptions of target populations [13, 14].

In addition and also contrary to the majority of previous publications, we included three countries in our study. These three countries are located in different geographical regions of the EU to be able to explore cross-country variations as fairly as possible. The aim of this study is to explore how individuals across Europe, namely in Austria, Belgium and Croatia perceive and recognize the difference between a common cold and influenza. The objective is to gain an understanding of laypersons’ reasoning, concept of knowledge and descriptions as well as investigate cross-country variations.

This study illustrates laypersons’ perceptions of two infections, the common cold and the influenza infection across the three European countries Austria, Belgium and Croatia. Respondents describe symptoms, distinguishable characteristics and perceptions about pathogenesis primarily based on their personal assumptions and support it by their individual experiences. Only a few participants made generalisations about diseases, medical signs and evidence-based practices and most descriptions included primarily important personal accounts of illness experiences. Surprisingly, the differences in the perception of lay persons is more divers within one country than between the countries, the overall perception in all three countries regarding [1] perception of common cold as harmless and individualistic disease, [2] influenza and its distinctive characteristics and [3] perception of pathogenesis and disease progression is similar: It is noticeable that across all three countries, we found that respondents possess a fairly accurate perception of symptoms for both diseases. At the same time results show that many are not familiar with biomedical concepts of the two diseases and it is difficult for many people to make a clear distinction. However, also clinical diagnosis of influenza is difficult because symptoms range in severity and overlap with those caused by other respiratory viruses [13].

The common cold infection is identified as generally harmless and signs and symptoms are interpreted as individualistic, depending on the person, health condition, and external circumstances. It is perceived as self-treatable, only with particularly severe symptoms participants explain to take rests, adapt their behaviour and daily routine. There were some unique positions from participants, such as that the onset of a cold is gradual or abrupt, some typical common cold symptoms were only mentioned once or twice, and that a common cold may last longer than a couple of days.

Based on the strong link on individualistic understandings of symptoms and both diseases this study found a less clear distinction between the diseases as compared to findings in Cedraisch et al. [24].

Although lay persons seem to know that influenza is more severe than common cold, the criteria which they identify with influenza concentrated more on symptom pattern: fever, limb ache, and not being able to work. This finding is similar to other publications, where laypersons were asked how they identify the flu [24, 25]. Meanwhile, fever is not always a sign of influenza [26]. In contrast, common colds can present with fever and limb ache as well. What seems noteworthy is that some respondent mentioned differences at the onset of the two diseases, although results were rather vague. The differences at the beginning of the disease (in most cases gradual onset for common cold versus sudden high fever for influenza) appear to be the best clinical criteria for the differentiation [2, 13].

Interestingly the results do no not include explanations on the self-limiting characteristic of both diseases, and that therefore the standard treatment is targeted towards symptomatic relief [1, 3, 5].

It has to be mentioned that for laypersons across the three countries the linguistic differentiation is of particular difficulty because in everyday language common cold is often referred to as “flu”, and expressions like flu-like infections (in German: “grippaler Infekt”) may suggest that it is linked. This is a common misconception in many English speaking countries as well, including the United States.

In addition, most respondents did not refer to different viral pathogens (i.e. rhinoviruses, adenoviruses, parainfulenzaviruses etc.) and infectious agents that constitute each disease. In some cases it was even stated that a transition from common cold to influenza is possible. Explanations included ideas of transitions, developments and shifts from one to the other; while relatively little emphasis is given to communicableness of both viral infections.

These perceptions are especially relevant if we take into account the issue of prevention and for instance the attitudes towards influenza vaccinations. From all participants only less than 6% (15/85) got influenza vaccination in the respective year, which is linked to perception of risk groups and attitudes towards illness, illness transition and influenza vaccination. Therefore, the hesitancy or otherwise the proactive seeking of influenza vaccination and also other preventive measures as well as treatment, seems to be a consequence of a lack of knowledge. Awareness raising activities, such as a brief explanation by a GP or practice assistance could be an effective way to counter complications with influenza, low vaccination rates and inefficient treatment pathways. Interventions for improving health literacy on the common cold and influenza disease could start with explaining the differences at their early stage and increased distribution of rapid influenza tests to ascertain to assist with management decisions. Furthermore clinicians are advised to use timely epidemiological data to ascertain if influenza is circulating in their communities [13]. Therewith related the correct wording is equally important in order to decrease the risk of confusion of the common cold from influenza. Health campaigns could easily target term distinction. Improved knowledge of lay persons about influenza could have a positive impact on influenza vaccination and information about interaction of viruses and bacteria could also be crucial to counter antimicrobial resistance. This study suggests the importance of investment in health literacy to give people the chance to gain knowledge beyond that of their own experiences with illness.

The qualitative approach of our study underpins efforts to include the voices of patients in health research as well as to improve health promotion strategies derived from actual experiences, needs and perceptions of laypersons [14]. Preventive efforts and treatment advice must respond to the particular understanding of laypersons. A crucial element of such efforts could be to explain that standard infection containment initiatives focus on encouraging individuals with influenza-like illness to stay at home, seeking medical attention only in the presence of complications [25]. This entails knowledge about the element of it being a self-limiting, self-contained disease and treatment is advisable to relief symptoms. With regards to at risk-groups, this study’s findings are crucial while confirming other studies in this regard. Laypeople identify at-risk or vulnerable groups; however, do less frequently identify themselves to be vulnerable to influenza.

The study has some limitations. First, the participation of our respondents was voluntary, leading to the possibilities for selection bias. This means that respondents who have more time, are more interested in the topic, or think that they want to deal with this issues also through giving an interview are represented to a higher degree. Thus, understandings and perceptions that are described in this study may not reflect what average individuals understand as common cold, influenza and its differences. It is possible that individuals who in fact may be more affected by decisions about common cold and influenza treatment (e.g. children, elderly people) may have a particular perception on these issues that was not covered by this manuscript. Another limitation is that some interviews were very short. Because interview guidelines were slightly adapted according to each interview, our material provides an in-depth view into certain themes and touches other themes only rudimentary. This is a limiting factor, data analysis was driven by the available data that was collected, further studies would benefit from longer, more in-depth interviews and possible follow up interviews with respondents. The data is based on self-reports by participants, thus being subject to possible recall bias.

Another limitation is the fact that the sampling period in Austria (influenza season 2013/2014) is different from the one in the other two countries (influenza season 2015/2016). Fortunately, both influenza seasons were mild influenza activity seasons in Europe [27, 28] leading to the assumption that this factor does not have a bigger impact on the comparative results between the countries. However, since both seasons were mild the perception of lay persons regarding influenza might have been less alerted and kept in mind when it came to the different lay-concepts of the two diseases common cold and influenza.

We conclude that participants possessed a fairly good understanding of symptoms, differences and pathogenesis of common cold and influenza. While at the same time we found some existing misconceptions regarding fever as an indicator of influenza, some vague assumptions about gradual and/or abrupt onset of common cold, and the idea of a possible continuum from one disease to the other. There were very few cross country differentiations in results. Interventions for prevention and treatment should focus on misconceptions and misinterpretations and awareness raising activities as well as other knowledge dissemination strategies should be led by health care workers. All first point of contact actors, may it be physicians, GPs and practice assistants, should be strongly supported and incentivised in their role as knowledge mediators. Basic consultations and awareness raising activities must include biomedical explanations of infectious disease pathogenesis, focussing on symptom onset differentiation, and also include aspects of communicableness and the self-limiting nature of both diseases. An informed understanding of both infectious diseases is crucial and may also increase influenza vaccination coverage in the three respective countries effectively.