CONSUMERS’S WILLINGNESS TO PAY FOR AVOIDING SALMONELLA INFECTION

WTP question. Results indicate that an average respondent would pay 18.6 EUR to avoid salmonellosis. Main factors aﬀ ecting WTP were size of family and number of children. The numbers indicate that the consumer well-being loss could be about 1 786 060 EUR annually, resulting from the multiplication of the estimated number of annual salmonellosis cases and the average WTP value. It can be concluded that consumer well-being losses alone would call for further interventions in Salmonella eradication, not to mention other – more direct – cost elements.

Salmonella infection generally causes fever and diarrheal symptoms. Infections are mainly due to contaminated food (poultry, pork, raw eggs, etc.) consumption, which are incorrectly stored, but it may also be due to contact with an infected person or failure to comply with hygiene rules (A et al., 2014). Based on national statistics, the number of human salmonellosis continuously increased (a maximum of 28 000 cases per year) from 1960 to 1996 and has become one of the major public health threats for decades in Hungary (S et al., 2008). Therefore, this type of infection has become the best-known foodborne disease among the population. Even if the number of cases decreased from 1997, salmonellosis has remained one of the most important zoonotic diseases up to these days. While campylobacteriosis started to play a leading role in epidemiologic reports from 2004, Salmonella is still more widely known among the Hungarian population. While a simple google search delivers 13 100 hits for the Hungarian word for salmonellosis, a similar search in regard of campylobacteriosis only results in 534.
Compared to the average EU rate in 2004 and 2008, Hungarian rates of confi rmed cases were three times higher (74.7 and 66.1 vs. 42.2 and 26.4 per 100 000) (K et al., 2011). In 2017, when an increasing tendency was noted in many EU member states including Hungary, the rate of confi rmed cases was two times higher than the EU average (40.0 vs. 19.7 cases per 100 000) (ECDC-EFSA, 2018). In reality, however, the number of salmonellosis cases may be even higher. Based on a population survey (V et al., 2019), approximately 18 times more individuals are suff ering from Salmonella infection than it is offi cially recorded in the national epidemiological database. In Hungary, the fi rst guideline for reducing the level of Salmonella contamination was compiled and published by the Salmonella sub-committee of the Hungarian Academy of Sciences in 1995. In the late 90s, the monitoring of Salmonella Enteritidis and Salmonella Typhimurium had also been established. Following the accession to the EU in 2004, rules of the monitoring procedure had been modifi ed. As mentioned by S and co-workers (2010a), the protection against specifi ed zoonotic agents in animals and products of animal origin was initially based on the Council Directive 92/117/EEC. Further on, regulation is extended by two legal sources: Directive 2003/99/EC on the monitoring of zoonoses and zoonotic agents, as well as Regulation (EC) No. 2160/2003 of the European Parliament and of the Council on the control of Salmonella and other specifi ed food-borne zoonotic agents (EC, 2003a, b).
Based on the registered data, the EU goal was to reduce prevalence of certain Salmonella serotypes to less than 1% in poultry (breeding and broiler chicken, layer hen, breeding and broiler turkey). In order to achieve these aims, according to the Regulation (EC) No. 470/2009 of the European Parliament and of the Council (EC, 2009), the eradication programmes in the Member States were co-fi nanced up to 50% of the total cost by the EU.
Vaccination of poultry against salmonellosis in the Salmonella eradication program and the improving hygiene in food industry and food trade resulted in the decrease of human cases (S et al., 2010b). However, home-made preparation of food (heat treatment, avoiding cross-contamination) and personal hygiene remained crucial to prevent human infections (R et al., 2015). Salmonellosis causes signifi cant fi nancial losses for households, the healthcare system, and also for businesses (B et al., 1996, K et al., 2011). The costs of the disease fall into two categories: direct and indirect costs. In terms of eligibility, direct costs primarily include healthcare expenditures, while indirect costs consist of loss of income and productivity, as well as the loss of consumer confi dence in food safety (Table 1).
There are several methods to examine the social costs of foodborne diseases. One of the most widely used method is the so-called Cost-of-Illness Analysis (COI), developed by Malzberg in 1950Malzberg in (S & R , 2003. Another widely used approach is the Willingness to Pay (WTP) analysis that is based on the principles of welfare economics and measures the willingness of consumers to pay for reducing the risk of becoming ill.
The main aim of this research was to measure the willingness of the Hungarian consumers to pay for avoiding a commonly occurring diarrhoeal disease, salmonellosis. A second objective was to investigate the factors that infl uence the subjective judgment of the respondents in this matter. Costs of animal production -Morbidity and mortality of animals on farms, -Reduced growth rate/feed effi ciency and increased fattening time, etc.

Costs of disposal of contaminated animals on farm and at slaughterhouse
-Increased condemnation or extra treating at slaughterhouse, -Illness among workers because of handling contaminated animals or products, etc. Control costs for pathogens -New farm practices -Altered animal transport and marketing patterns, -New slaughterhouse and processing procedures, -New wholesale/retail practices, -Risk assessment modelling by industry for all links in the food chain, etc. Outbreak costs: -Herd slaughter/product withdrawal, -Plant closings and clean-up, Regulatory fi nes, -Reduced product demand because of outbreak, -Increased advertising or consumer assurances following outbreak, etc.
Disease surveillance costs -Monitoring of incidence/severity of human cases and pathogen incidence in the food chain, -Developing integrated database for foodborne pathogens, etc.

Consumer survey
In our work, we used the data of the Hungarian National Food Chain Safety Authority's 2017 survey (n=1001, personal interviews, representative sampling to age, sex, geographic distribution on NUTS2 level). The question related to willingness to pay to avoid Salmonella infection was answered by 460 persons. However, only numerical or quantifi able answers were taken into account. 'Nothing' or 'I do not want to pay more for safer food' have also been regarded quantifi able answers and meant 0. Distribution of numerical and quantifi able data was scattered. In order to exclude outliers, the commonly used box-and-whisker plot was applied (S & M , 2007) that resulted in a threshold value of 20 000 HUF (64.7 EUR) maximum (HUF/EUR exchange rate of 2017 was used (HCSO, 2017a)). Finally, the number of analysable WTP answers was 323 (Table 2). Even if responses (n=68) such as 'Being healthy is worth everything' or 'It is worth a lot' were excluded from the analysis, they also gave useful information on respondents' attitude and assessment. One fi fth (13 out of 68) of them stated our question on WTP was meaningless or not answerable, while 16.2% (11 out of 68) said value of health cannot be expressed in monetary values (Fig. 2).

Estimation of willingness to pay
There are several methods to assess consumer WTP. These approaches can be categorised by measuring WTP directly or indirectly and investigating hypothetical or actual WTP. They also diff er from each other in the type of questions used in the survey (e.g. open-ended, closeended, or bidding questions) (A et al., 2014). Our WTP analysis was based on one direct question with a defi nition. In order to estimate WTP to avoid salmonellosis, respondents had to answer the following question: 'How much would you pay for avoiding a Salmonella infection? (Salmonellosis is an infection, which generally causes diarrhoea, cramps, shivering, and relatively high fever with a recovery time of 3-4 days.)'.
Even if salmonellosis is mainly due to the consumption of a product of animal origin (especially eggs, poultry, meat, milk products), almost any food can become a source of infection. Also, a signifi cant share of Salmonella infection cases are caused by human-human interactions or poor general hygiene. In real life, the source of salmonellosis is often diffi cult to trace back. Therefore, identifi cation of the source is often based on assumptions (especially if it was a single case without further investigation). Hence, in this paper WTP was not used Acta Alimentaria 49, 2020 in regard of a specifi c food category (e.g. how much more you would pay for a Salmonella free egg compared to a normal one) but in a general sense about avoiding one Salmonella infection, with no regard of the cause.

Factor analysis.
Beside socio-demographic variables, we were also interested in the eff ect of other attributions. Thus, correlations, which were also necessary because of factor analysis, were tested between WTP answers, demographic parameters, and personal attributions (Table 3).
According to S & M (2007), factor analysis is commonly applied to reduce the number of correlated variables and to make the results of socio-economic surveys easier to understand. First, KMO and Bartlett's Test were used to determine whether our data fi t this type of analysis. Since KMO test resulted a value of 0.6 and Bartlett test proved that there were correlations between the variables, our data were considered appropriate to the analysis. As extraction method Principal Component Analysis, as rotation method Varimax rotation procedure were performed. In order to be accepted, the factors had to explain at least 60% of the total variance and their absolute value had to be equal or higher than 0.5.

Uncertainty analysis
The amount of money people would pay for avoiding salmonellosis varied considerably. In order to test normality, Kolmogorov-Smirnov and Shapiro-Wilk tests were performed. Test results showed a multimodal distribution in WTP data.

Survey data on Hungarian WTP for safer food
The mean of consumer WTP of those who would spend money to avoid Salmonella infection was 5746 HUF (18.6 EUR), the median value 5000 HUF and the mode 10 000 HUF. We found that 73 out of 323 individuals totally rejected to pay more for avoiding food-borne infections, while 110 of them would have paid 10 000 HUF (32.3 EUR) or more, which is at least twice the amount spent on a weekly food-shopping in Hungary.

Relationship between WTP and demographic parameters
Results obtained from Pearson's chi-square test showed that relationship was signifi cant (P=0.000) not only between consumer WTP and age groups, but also between WTP and level of education (P=0.000). Contrary to what we expected, economic status had no eff ect on consumer WTP (P=0.844).

Main factors aff ecting Hungarian consumer WTP
Results from factor analysis showed that our variables, which signifi cantly characterize our respondents, can be described by 5 factors (Table 5). The fi rst factor, which was named 'complexity of the household', included the number of children under the age of 15 and the size of the household. The second group, 'role in the family', consisted of: gender, responsibility for food at home and following a special diet. These parameters generally characterize women. The third factor called 'susceptibility' involved both age group and the fact that respondents had health symptoms like fever, diarrhoea, vomiting, which occurred last year. According to public health data, among age groups younger and elder suff er more often from Salmonella infection (S et al., 2008). Group 4 included only the type of residence, while the last one consisted of the level of income and education. According to scientifi c literature, there is a general link between these two demographic parameters (R , 2013).

Discussion of the results
Compared to many other countries (F et al., 2016) the number of publications on how much consumers are willing to pay for avoiding certain health risks is very limited in Hungary. Studies on the WTP to avoid any type of zoonotic disease are completely absent up to this day. Our fi ndings give a picture of the Hungarian consumers' willingness to pay for avoiding one of the most frequently occurring zoonotic disease, salmonellosis. Due to the lack of similar research in Hungary, comparison of our results with previous national data is not possible. The results show, however, that the age group and higher level of education had a signifi cant eff ect on consumer WTP. These fi ndings are partially in line with fi ndings of R (2013), who estimated the WTP to avoid a climate change disease. He also found WTP was statistically infl uenced by the level of income. In our study, in contrast to what we expected, this relationship was not signifi cant. At the same time, respondents could be signifi cantly characterized by 5 main factors, from which the fi rst was the 'complexity of households'. This factor included the number of children under the age of 15 and the size of the household. In his work, R (2013) also stated that higher number of family members under the age of 18 had a positive impact on WTP. Analysis of the eff ect of demographic factors may give a hint about the segmentation of the society about undertaking food safety risks. However, the ratio of valid responses was lower than expected; only 460 out of 1001 total respondents gave relevant answer. The most important experience was that for many people the notion of expressing health related issues in monetary terms was ethically disturbing or did not make sense at all (assumingly they would need a causal relationship).

Conclusions
Despite the relevance of the subject, no study has been published on consumers' WTP to avoid salmonellosis to date. In our survey we found that the mean of consumer WTP of those who would spend money to avoid Salmonella infection is 5746 HUF (18.6 EUR). This amount of money is close to the average food shopping expenditure per capita per week (5628 HUF/18.2 EUR) in Hungary (HCSO, 2017b).
However, it is very challenging to express the monetary value of health. Our fi ndings may give an indicator for policy makers about the well-being eff ect of Salmonella reduction on the population level. In our previous study, estimated total (reported and latent) number of salmonellosis was 96 048 cases in average per year (based on the average number of cases 2012-2016, multiplied by a country-specifi c factor (V et al., 2019)). Only a 10% drop would deliver (96 048 cases×0.1×5746 HUF =) 55 189 180 HUF (178 606 EUR) gain in the perceived well-being of the consumers alone.
Considering other factors as well, such as direct cost savings in the public health sector, households and companies, we may conclude that fi nding and fi nancing further interventions (especially risk communication of household food safety issues) for Salmonella reduction would be benefi cial on social level. *