Background
An outbreak of
Giardia lamblia-induced enteritis occurred in Bergen City, Norway, during the summer and fall of 2004 because of contaminated public drinking water [
1] subsequently attributed to a leakage in a sewer pipe and an insufficient purification process [
2]. Following the acknowledgement of the outbreak, people were instructed to boil the tap water before drinking it and take precautions. The outbreak was acknowledged by the local public health authorities, the National Institute of Health, the Municipality of Bergen City and the Water Work that supplied the water. In addition, the municipality’s insurance company got involved. An evaluation report of the outbreak was issued by the Norwegian Food Administration in 2006 [
2]. Some of the persons infected subsequently developed chronic fatigue syndrome [
3]. In this study, we explore the experiences of living with this condition 4 years following the outbreak.
People around the world suffer from post-infectious fatigue syndrome (PIFS) [
3‐
5], also termed post-viral fatigue syndrome (PVFS) [
6] or myalgic encephalomyelitis (ME) described following outbreaks [
7] and used in the international consensus criteria with reference to infectious onsets [
8]. No case definitions for PIFS exist. In the case definition used to diagnose the affected persons, the term chronic fatigue syndrome (CFS) is used [
9]. However, the term PIFS will be used here because the study sample had a confirmed infectious onset.
Because
Giardia l. is not endemic in Norway [
1], the knowledge among health professionals was low and the parasite not routinely tested for. In Norway, the population is covered by a national health care system funded by taxes. Thus everyone has access to a wide range of health services.
Many developed tiredness or severe fatigue in the aftermath of the infection, making them more or less disabled. Infectious onset is known [
8,
10], but the aetiology remains unclear. A loss of 50% or more of pre-illness functional level is required to meet diagnostic criteria, as well as profound fatigue lasting for more than 6 months Fukuda 1994 [
11]. Lack of energy and stamina, post-exertional neuroimmune exhaustion (PEM), easy fatigability, sleep abnormalities, immunological dysfunction and neurological and autonomic complaints are prominent features [
8]. A range of abnormalities are underlying this condition, among them are decreased cerebral oxygen and blood volume/flow [
12,
13], lower body venous pooling [
14], impaired delivery of oxygen to muscles [
15], delayed restitution period [
16], orthostatic intolerance [
17] and exercise intolerance [
12]. Currently, no curative treatments are available. Thus, affected persons are left with symptom alleviation and having to learn how to manage their symptoms [
18]. Complete recovery is rare as less than 5% of individuals recover to pre-illness functional level [
19]. PIFS has a greater impact on functional status measured by disease specific norm scores on SF-36 Short Form compared with other diseases such as depression and cancer [
20]. Persons with PIFS have lower functional status than persons with HIV [
21], rheumatoid arthritis [
22], end stage of kidney failure and heart disease [
23]. They are also more functionally disabled than persons with multiple sclerosis (MS) [
24]. Only terminally ill people with cancer or stroke have functional scores similar to persons with PIFS [
23]. Minor exertions, whether physical, cognitive or emotional, may provoke increased fatigue, symptom exacerbation and functional decline [
25]. A significant increase in functional capacity is rare [
26,
27], thus PIFS results in substantial reduction in quality of life [
22]. Globally, millions of people are affected; the prevalence rates are in the range of 0.20%–0.42% [
28,
29].
The economic impact on society is substantial [
30] and includes loss of employment and productivity that amounts to millions of pounds in the UK [
31]. In addition, in the US, more than 18 billion dollars are spent annually for direct health care costs (hospital admissions and out-patient visits, prescription drugs, medical examinations), indirect costs (disability benefits, lost productivity, informal care) [
32] and to reduced income tax revenue [
33]. Annual national loss of household productivity due to PIFS in the US is greater than in nervous system disorders [
34]. The impact on the affected individuals is substantial as well [
32,
35], because the personal consequences encompass escalating health care costs, user charges, loss of income for themselves and their household, reduced standard of living, huge out of pocket expenses [
32], low educational attainment and lower lifetime earnings [
30]. The percentage of participants unemployed at baseline varies between 27%- 65%, and the number returning to work at follow-up ranges from 8 to 52% [
19]. The prognosis of returning to work is poor [
19]; thus, the reduced functional ability in professional life is substantial [
36,
37]. The percentage of individuals living on disability benefits ranges from 25%- 42% [
38,
39] and many are dependent on significant others for financial support [
40]. Because 90–95% of adults remain chronically ill [
19], the multitude and magnitude of the suffering, losses and costs for the affected persons, their families and society, this condition constitutes an important public health issue [
41].
To reduce the societal and personal impact, we need not only knowledge of the fatigue experience itself [
42], but also what factors impact PIFS in the first years of the illness trajectory. Models may enable health care providers to better understand how PIFS progresses over time and the ill persons’ own reactions to live with it [
43]. Models may also help the health care services to deliver improved care, thereby contributing to faster recovery, increased functioning and, hopefully, regaining pre-illness study and work capacity. Few studies have explored trajectory models. Fennell Phase Inventory (FPI), a four-staged model of coping with the condition, comprises life domains such as cultural, physiological, psychological, social and work performance [
44]. The model tries to clarify the fluctuating condition and the totality of the illness experience. Ware’s [
45] sociosomatic model defines the affected person’s illness as a social experience and is based on the assumption that bodily distress is a result of embodied social problems that are expressed as physical complaints. Whitehead’s [
46] trajectory model of three illness-constructed narratives comprises the quest, chaos and restitution phases. These narratives are used to understand the affected person’s illness experience in different phases. However, these models have not explored how the illness and disability trajectory evolves over time during a natural course of the condition following a confirmed infection. Thus, the authors have previously proposed a model of disability trajectory (PIFSDM) consisting of five phases: prodromal, downward, transition, upward and chronic [
47]. This model outlines the phases and changes in illness severity and different disabilities over time.
International Classification of Function (ICF) defines disability as “
the outcome or result of a complex relationship between an individual’s health condition and personal factors, and the external factors that represent the circumstances in which the individual lives” (p.23) [
48]. Disability is the lack of or reduced ability to uphold normal financial, vocational and personal standards due to various impairments [
48]. The aims of disability management are situational adjustment and behavioural change, but persons with disabilities face barriers in accessing health, social and rehabilitation services [
48].
One significant barrier may be a lack of knowledge of how different factors impact each phase of the trajectory. When factors influencing the trajectory have been identified, this knowledge may serve as a tool for assessment and treatment, making it possible to plan and implement tailored treatment programs. This may increase functional ability and optimize health for the affected individuals, reduce barriers and costs to society and improve health care services. To our knowledge there are no studies focusing on the role of impacting factors during a trajectory spanning 4 years. Thus, there is a need for a more complete picture of factors that impact PIFS over time. The aim of our study is to explore, from the perspective of persons with PIFS, factors that affected their illness trajectory and how these factors may have played a role during each phase of the trajectory.
Discussion
The aim of our study was to explore experiential factors impacting each phase of a four-year long illness trajectory. Lay people who fall ill with a new and serious condition such as PIFS, lack knowledge and skills to manage their new condition. Thus, they need to rely on the health care system for adequate help to prevent or limit the consequences and be provided with proper advice and treatment to facilitate improvement in health and functional ability. However, our findings suggest that when the participants struggled hardest to cope with increasing disabilities during the downward phase, they received unhelpful or counterproductive advice from health care providers and lack of medical and financial support. This combination may have contributed to the severe downward trajectory that the participants experienced.
As early diagnosis is assumed to improve prognosis [
72], a delayed diagnosis and treatment of
Giardia l. enteritis [
1] and a delayed PIFS diagnosis and education about the condition kept the participants ill and untreated for a prolonged time with potential harmful consequences, such as avoidable severe decline in health and ability to function. Other external unhelpful impacting factors identified in our study have also been found previously. These include strained medical encounters [
73], misdiagnosis [
74], GPs uncomfortable making a diagnosis [
75], experience of disbelief, lack of knowledge and medical support and psychologizing of symptoms [
73], unsupportive GPs [
46,
76], being let down by the health professions [
77] and poor communication with health care providers [
78]. Our findings of context-specific experiences are in line with previous qualitative studies [
79].
During the downward phase, the participants were overwhelmed by their situation and lacked the ability to reflect on their own needs [
42]. Thus, it took them a long time to accept being seriously ill and recognize that keeping up with their pre-illness lifestyles was counterproductive and that they had not handled their situations appropriately. Their needs for help, whether practical, financial or educational, had not been taken seriously, nor adequately provided for. Because they had no prior experience with PIFS and lacked support from their GPs and a medical framework provided by the diagnosis, the participants were unable to interpret their illness experience and cope with it in a health promoting way. Instead, they interpreted their new challenges through the lens of being healthy. Using coping strategies from pre-illness life showed to be maladaptive during this phase of the trajectory [
80]. Our findings of internal unhelpful impacting factors are consistent with previous studies; they include being in denial [
81], or overwhelmed [
77], feeling insecure [
82], trying to fight the condition off [
77], feeling guided by moral values [
83,
84] and disruption of the self and the body [
84], reacting emotionally [
81], returning too early to work and taking insufficient time to recuperate [
83]. The negative impact on the downward trajectory was doubled as unhelpful internal factors and maladaptive coping strategies [
80] only added to the unhelpful external factors.
During the turning phase, the participants started to accept that they were ill and recognized the importance of adapting to their needs. With the interpretive framework grounded in the diagnosis, helpful advice, practical help, medical and financial support and education, the participants were able to manage their new life in a more adaptive way. Acquiring knowledge is important to regain control [
85] and reduce feelings of chaos and insecurity [
46]. In line with our findings, important internal factors during the improvement phase were keeping the energy expenditure lower than the perceived energy at any given day [
86], setting limits and planning activities [
46], pacing to avoid symptom exacerbation [
87], getting sufficient rest, monitoring activities, making lifestyle adjustments, occupational shift, reduction in social life [
88], and adaptation to the fluctuating symptoms [
89]. Consistent with previous findings, the participants in our study were more confident in managing their condition and its limitations in the chronic phase and used more adaptive coping strategies [
90].
Demographic characteristics such age, gender and education in our study are consistent with previous samples [
1,
87,
91] and did not seem to have a significant impact. A similar pattern of impacting factors was identified during the phases of the illness trajectory in all of the interviews. However, the ability to function varied among them, and some were more affected by impacting factors than others.
Acceptance is crucial [
77], as is access to practical aids, home help, adapting the housing situations [
77], gaining insight into PIFS [
77] and having a sense of control [
77] to facilitate improvement in functional ability. However, contextual elements such as lack of proper health services, lack of referral system and time- and energy-consuming difficulties with the social security system and the municipality’s insurance company imposed a significant emotional burden on these severely ill persons, draining them of energy that could be used in a more health-promoting way. A strained economic situation due to the inability to work, difficulties obtaining benefits and economic support were unhelpful and hampered improvement. Without financial means, some individuals were forced to work or to work too much, and were unable to pay for home help, childcare assistance, physiotherapy or psychological services needed to help them deal with their reactive psychological challenges. Other contextual elements were lack of knowledge among health care providers and no established system for taking care of persons with PIFS.
Unhelpful internal impacting factors played an important role, but these impacting factors could have been significantly reduced if an appropriate health care system, medical care and support systems had been in place. Helpful external impacting factors came too late and were insufficient, resulting in a prolonged period during which unhelpful internal impacting factors played a significant role. Impacting factors played an important part during the four-year long illness duration, but it is impossible to know to what extent the experienced impacting factors influenced the symptom severity and the disability level in each phase, as symptom severity and disability trajectory are influenced by underlying pathological mechanisms in various body systems [
11].
In this study we propose a new model of external and internal factors that either impact positively or negatively in each phase of the illness/disability trajectory. This model may enhance the understanding of the fluctuating trajectory and make it possible to identify which phase a person with PIFS is located in, to assess factors that impact the person and to tailor the treatment in accordance with impacting factors. Our model may function as a robust lens to understand how the illness and the impacting factors change over time as the affected persons learn to live with their chronic condition. In example, there is empirical evidence for phases of coping identified by Fennel’s Phase Inventory [
92,
93]. As well as dynamic changes in coping, there are also dynamic changes in our proposed model of impacting factors.
Fennel’s [
44] coping model revealed negative internal impacting factors such as denial, the fight to continue with pre-illness lifestyle and external negative factors such as misinterpretation of symptoms, trivialization of symptoms, stigma and societal moral values. Whitehead’s [
46] model of constructed illness phases identifies one positive impacting external factor: receiving diagnosis is important to reduce the emotional burden. Negative external factors were unsupportive GPs, the struggle to obtain a diagnosis and the contested view of the condition. Positive factors were information-seeking to find out how to improve health, changing lifestyle, setting limits and adjusting workload. In Ware’s [
45] model of social illness course negative impacting factors included poor economic situations, moral work ethics, stigma and positive factors included shifting to easier jobs, working less hours during the week and setting limits and prioritizing tasks.
Contrary to the findings by Fennel’s [
44], Ware’s [
45] and others [
94], the feeling of stigma attached to the diagnosis of PIFS only played a small part in this study. However, several participants experienced embarrassment due to various disabilities. The reason for this may be that the participants were part of a healthy group that had fallen ill by drinking contaminated public water, an emergent public health issue, thus they were not to be blamed for the reason to contract the
Giardia l. infection.
Although the aforementioned models have reported some negative and positive impacting factors found in our model, the impacting factors have not been organized into positive and negative external and internal factors in a structural framework. In our framework we present impacting factors that are associated with different phases of the trajectory. We also present findings of retrospective self-rated trajectory by using Bell’s Disability Scale [
55], and these findings of ability to function at different points in time confirm the participants’ accounts of their illness course and help to visualize the fluctuating character. This scale may assist in monitoring the trajectory. Our previously proposed disability model of PIFS (PIFSDM) [
47], the models of Fennel [
44], Ware [
45], Whitehead [
46] and the proposed model of impacting factors in PIFS (PIFSIM) during a four-year long trajectory, presented here, may be seen as complementary means to understand the evolving condition and facilitate clinical observations and help planning treatment in accordance with the needs of each phase. All models are flexible and take into account the relapsing and remitting nature of the condition. Persons with PIFS need respect and empathy from health professionals and help to rebuild their lives [
95], in addition to improved services and support [
96].
Implications for practice, education and research
Most health care providers in clinical practice have little or no knowledge of PIFS and do not feel confident in making the diagnosis or deciding how to treat persons with this condition. Enhanced knowledge among professionals who encounter this group may increase awareness of the seriousness of PIFS, the fact that it may follow various infections, how the trajectory unfolds and impacting factors associated with different phases. A better understanding of the condition may contribute to more accurate assessments of symptoms and functional ability and facilitate planning and organizing of appropriate health services. Individually tailored treatments and support services may be more health-promoting, effective and less costly. Educated health care providers would likely provide better quality of care in order to enhance the functional levels of affected individuals and reduce the use of health care resources. Lack of knowledge suggests a need for inclusion of PIFS (or post-infectious ME) in the curriculum at all levels of health care education. The proposed model of impacting factors has to be interpreted with caution, however. Our findings need to be replicated in other populations with this condition. Future research might be directed at evaluating what interventions are most appropriate in each phase of this condition to find out which ones will have the most helpful effect on reducing the downward trend, facilitating the improvement process and increasing the ability to function.
Strengths and limitations
The strengths of our study are open-ended interviews of persons with first-hand experiences, a well-defined maximum variation sample and a confirmed infectious onset. We do not draw any conclusions about causality between the Giardia l. infection and PIFS because this is outside the scope of a qualitative interview study. Besides, the pathophysiological process from contracting an infection to development of PIFS is still unknown. Our interview sample is selected from a defined cohort, the total Giardia PIFS cohort. The participants had been provided with the PIFS diagnosis by an experienced neurologist at Haukeland University Hospital, Norway, prior to recruiting the sample and conducting the interviews. In addition, the outbreak constituted a public health issue, acknowledged by public health authorities and the Municipality of Bergen City. Our study has several limitations. Aspects associated with a number of impacting factors may have been left out. Several participants reported memory gaps, and as our study is retrospective, our findings are therefore vulnerable to recall bias. None were bedridden or housebound at enrolment, but had been during the time of their lowest functional level. As our sample was recruited from a tertiary clinic, the findings may not necessarily reflect experiences of population-based samples. Our sample had an infectious onset, giardia duodenalis, and may deviate from samples wherein PIFS was contracted following exposure to other infectious agents. The findings may not be applicable to all affected persons or other populations with gradual onset without a confirmed infection because this condition is considered heterogeneous. However, our findings may be transferable to other populations of post-infectious syndrome because many of our findings are consistent with previous research.
Conclusion
The participants experienced several impacting factors, whether external, internal, helpful or unhelpful, associated with each of the five illness phases. The participants expressed several unhelpful internal factors that impacted the downward phases, and these made them make unhelpful or potential harmful decisions on how to manage their illness. The downward phases are critical periods of time, and the combination of unhelpful internal impacting factors coupled with the unhelpful external impacting factors related to the health and social care system, the social security system (Norwegian Labour and Welfare Service) and the municipality’s insurance company during this time, may have had a negative impact, resulting in an unnecessary severe disability and prolonged time of being severely disabled. Helpful internal factors such as acceptance and years of trial and error learning contributed to a turning phase and made the participants take more control during the upward phases. Poor economy was experienced as a negative impacting factor hampering improvement. Both practical and financial support was experienced as critical factors, because this made it possible for the affected persons to rest enough to regain energy and increase their functional abilities.
The health care system, including the specialist and GP services, and the social security system, had more or less failed, despite the fact that internal and external impacting factors during the illness trajectory have been known for many years. The participants’ experiences of unhelpful professional attitudes, in addition to lack of knowledge and support, suggest a significant potential for improvement regarding care, treatment, education and assistance. There is a need for better cooperation between individuals with PIFS, the health care providers and the social security system. If more appropriate health care services and other support systems had been in place earlier, adapted to each illness phase, the illness trajectory and severity may have had a more favourable outcome. Insufficient or faulty health care services may pose a burden on both the individual and society, in terms of severe disability, lost productivity and inefficient and unnecessary costly health care services.
Enhanced knowledge may change health care providers’ attitudes to persons with PIFS in a positive direction and contribute to improved and flexible health and social services, and other support systems. Our presented model of impacting factors associated with a five-phased trajectory of PIFS may provide a tool to develop more tailor-made health care and other services during the different phases that ultimately may lower costs to the individual and society.