Assessment of the risk of African swine fever introduction into Finland using NORA-a rapid tool for semiquantitative assessment of the risk.

The NORA rapid risk assessment tool was developed for situations where there is a change in the disease status of easily transmissible animal diseases in neighbouring countries or in countries with significant interactions with Finland. The goal was to develop a tool that is quick to use and will provide consistent results to support risk management decisions. The model contains 63 questions that define the potential for entry and exposure by nine different pathways. The magnitude of the consequences is defined by 23 statements. The weight of different pathways is defined according to the properties of the assessed disease. The model was built as an Excel spreadsheet and is intended for use by animal health control administrators. As an outcome, the model gives the possible pathways of disease entry into the country, an overall approximation for the probability of entry and the subsequent exposure, an overall estimate for the consequences and a combined overall risk estimate (probability multiplied by magnitude of consequences). Model validity was assessed by expert panels. Outside Africa, African swine fever is currently established in Russia and Sardinia. In addition, there have been cases in both wild boar and domestic pigs in Latvia, Lithuania, Poland and Estonia. Finland has frequent contacts with Russia and Estonia, especially through passengers. The risk of African swine fever (ASF) introduction into Finland was tested with NORA for the situation in December 2015, when ASF was endemic in many parts of Russia, Africa and Sardinia and was present in Baltic countries and in Poland. African swine fever was assessed to have a high probability of entry into Finland, with high consequences and therefore a high overall risk.

Simulated financial losses of classical swine fever epidemics in the Finnish pig production sector.

Rapid structural change and concentration of pig production in regions with most intensive production has raised concerns about whether the risk of large-scale disease losses has increased in Finland. This paper examines the pig industry's losses due to classical swine fever (CSF) epidemics. The work is based on economic and epidemiological models providing insights to the consequences of epidemics to infected and uninfected farms, government and meat processing. The economic analysis was carried out by use of a sector model, which simulated the recovery of pig production, starting from the recognition of the disease in the country and ending at a steady-state market equilibrium about 12 years later. The model explicitly took into account profit-maximising behaviour of producers and the effects of decrease in export demand. Epidemiological evidence suggests that under the current spatially diversified structure of Finnish pig farming and related industries, the probability of a severe disease epidemic counting dozens of infected farms is small. Even for epidemics considered large in Finland (5-33 infected farms) combined with a major reduction in export demand, the median loss was simulated to be only euro19.2 million. The majority of these losses were due to loss of exports corresponding almost 20% of pig meat production in Finland. While the current structure of pig farming in Finland incurs higher production costs than the most intensive structures in Europe, it also seems to decrease the probability of 'catastrophic' economic losses. The results suggest that the response of export markets and the number of uninfected farms affected by preventive measures are critical to the magnitude of losses, as they can amplify losses even if only few farms become infected.

Simulated detection of syndromic classical swine fever on a Finnish pig-breeding farm.

Although Finland has not experienced a classical swine fever (CSF) epidemic since 1917, the concern about early detection is relevant. The time until detection of CSF on a pig-breeding farm was predicted by simulation, and earlier detection of CSF-infected farms was assessed. Eight to 12 weeks will pass before CSF is detected on a Finnish pig-breeding farm, which resembles detection of the index farm for actual CSF epidemics in Europe. Although notification of suspected CSF on the infected farm accelerates detection the most, interventions aimed at promoting investigations of the general health problem noticed on the farm, or a more comprehensive testing of samples currently arriving from pig farms to the investigating laboratory could shorten detection time by 3 weeks. Results are applicable for further simulation of an event of a CSF epidemic in Finland, and for studying contingency options to promote more rapid detection of infectious diseases of swine not found at present in the country.

Cadmium intake of moose hunters in Finland from consumption of moose meat, liver and kidney.

Although the average cadmium intake in Finland is about 10 microg day(-1), some risk groups can be identified. This study assessed cadmium intake from the consumption of moose meat, liver and kidneys by moose hunters. Consumption data from a postal questionnaire were combined with a representative database on moose cadmium concentrations. Cadmium intakes were calculated as point estimates for all respondents (n = 711), for those consuming moose meat, liver and/or kidneys, and for the highest decile of those. Probabilistic modelling using the Monte Carlo technique was used to simulate the distribution of dietary cadmium exposure. Of the respondents, 69% consumed moose liver and only 23% moose kidneys. The consumption of moose liver or kidneys significantly increased cadmium intake, whereas moose meat (median consumption 17 kg year(-1) person(-1)) contributed only slightly (0.16 microg day(-1) person(-1)) to the daily total cadmium intake. In the simulation, 10% of the moose hunters had an intake of > 8.76 microg day(-1) (14.6% of PTWI for a 60-kg person) from moose. Point estimates provided only a partial understanding of the potential exposure. Simulated distributions of intake were more useful in characterizing exposure. The study revealed that heavy users of moose organs have a relatively narrow safety margin from the levels of cadmium probably causing adverse health effects.

Temperature effect on the immune defense functions of Arctic charr Salvelinus alpinus.

The Arctic charr Salvelinus alpinus is an endangered fish species in Finland, and thus farming is carried out mainly for stocking purposes. Farmed charr are susceptible to infection with atypical Aeromonas salmonicida (aAS). Losses of valuable brood stock will severely reduce the genetic diversity of stocked charr. No commercial vaccines are available to prevent aAS infection, and vaccines against furunculosis (caused by typical A. salmonicida, tAS) do not protect the charr against aAS infection. The effects of a metabolizable oil-adjuvanted, bivalent vaccine (containing killed aAS and A. salmonicida salmonicida bacteria) on the immune system of 1 yr old hatchery-reared charr originating from Lake Inari in Northern Finland were examined. Fish vaccination in Finland generally takes place either from October to November or from February to April, when the water temperature is low (1 to 3degrees C). The water temperature starts to increase in mid-May. Therefore, we also investigated whether post-vaccination (p.v.) temperature had an influence on the immune system of this cold-water fish species. The fish were immunized intraperitoneally at 2.9 degrees C at the end of April. After 52 d, during which the water temperature increased from 2.9 to 10.0 degrees C, the charr were exposed to 1 of 3 test temperatures: 10.3, 14.1 or 18.1 degrees C. Prior to vaccination, and 49, 75 and 103 d p.v., several immune parameters were measured in both unvaccinated and vaccinated charr. Vaccination induced a significant anti-aAS-specific antibody response, and increased plasma lysozyme activity at all p.v. temperatures. The haemolytic activity of the complement system was unaffected either by vaccination or p.v. temperatures. There was a slight positive correlation between p.v. temperature and lysozyme activity of the charr. The significant increase in lysozyme activity took place in vaccinated charr in the first 49 d p.v. as water temperatures increased from 2.9 to 10 degrees C. Furthermore, the highest activity of lysozyme in the plasma was observed 49 d p.v. Our results indicate that a rise in water temperature above 10 degrees C does not significantly enhance the vaccination response of charr. This could be one reason why farmed Arctic charr, which are well adapted to a cold climate, are highly susceptible to aAS infection in the summer.

Vaccination influences growth of Arctic charr.

There is limited knowledge about the effects of oil-based vaccines on the growth of Arctic charr Salvelinus alpinus, in particular at different rearing temperatures. One-year-old Arctic charr were immunized intraperitoneally at 2.9 degrees C with a metabolizable oil-adjuvanted, bivalent vaccine containing killed typical and atypical Aeromonas salmonicida bacteria. After vaccination the non-vaccinated (controls) and vaccinated individually marked fish were held for 20 d at 10.0 degrees C and then for 7 wk at 10.3, 14.1 or 18.1 degrees C. During the first 20 d at 10.0 degrees C the growth rate (G) was higher for non-vaccinated than vaccinated fish. Thereafter vaccinated charr had higher G than control fish at 10.3 and 14.1 degrees C. In contrast, at 18.1 degrees C there was no difference in G and therefore no compensation of earlier growth suppression in vaccinated fish was observed at that temperature. The study indicates that vaccination has no ultimate negative effects on the growth of Arctic charr at temperatures ranging from 10.3 to 14.1 degrees C.