Molecular and serological investigation of Hepatitis E virus in pigs slaughtered in Northwestern Italy.

BACKGROUND: Hepatitis E Virus (HEV) is recently considered an emerging public health concern. HEV genotypes 1 and 2 are widely distributed and pathogenic only for humans. In contrast, HEV, genotypes 3 and 4 are observed in swine, deer, wild boars and rabbits and can also be transmitted to humans. The presence of HEV in the liver, muscle, faeces, blood, and bile was detected by real-time RT-PCR in 156 pigs belonging to twenty different farms, ranging from 1 to 8 months of age. The phylogenetic analysis was performed on the viral strain present in the positive biological matrix, with the lowest Ct. HEV-IgG and HEV-IgM in the sera were analysed by two different ELISA kits. RESULTS: Twenty-one pigs, i.e., 13.46% of them (21/156, 95% CI: 8.53%-19.84%), tested positive for HEV in at least one biological matrix by real-time RT-PCR, while phylogenetic analysis revealed the presence of HEV subtypes 3f and 3c. Pig serums analysed by ELISA showed an overall prevalence of 26.92% (42/156, 95% CI: 20.14%-34.60%) for HEV-IgG, whereas the 28.95% (33/114, 95% CI: 20.84%-38.19%) of them tested negative resulted positive for the HEV-IgM. CONCLUSIONS: The faeces are the biological matrix with the highest probability of detecting HEV. The best concordance value (Kappa Kohen index) and the highest positive correlation (Phi index) were observed for the correlation between bile and liver, even when the number of positive liver samples was lower than the positive bile samples. This finding may suggest that a higher probability of HEV occurs in the bile, when the virus is present in the liver, during the stages of infection. Finally, the presence of HEV in muscle was observed in 11 pigs, usually used for the preparation of some dishes, typical of the Italian tradition, based on raw or undercooked meat. Therefore, their consumption is a possible source of infection for final consumer.

Inferences about the transmission of lumpy skin disease virus between herds from outbreaks in Albania in 2016.

Lumpy skin disease has recently emerged as a major threat to cattle populations outside of Africa, where it is endemic. In 2015 the first ever European outbreaks occurred in Greece, which were followed by spread across much of the Balkans in 2016. Here we use a simple mathematical model for the transmission of lumpy skin disease virus (LSDV) between herds to explore factors influencing its spread by fitting it to data on outbreaks in Albania in 2016. We show that most transmission occurs over short distances (<5 km), but with an appreciable probability of transmission at longer distances. We also show that there is evidence for seasonal variation in the force of infection associated with temperature, possibly through its influence on the relative abundance of the stable fly, Stomoxys calcitrans. These two results together are consistent with LSDV being transmitted by the bites of blood-feeding insects, though further work is required to incriminate specific species as vectors. Finally, we show that vaccination has a significant impact on spread and estimate the vaccine effectiveness to be 76%.

Neethling vaccine proved highly effective in controlling lumpy skin disease epidemics in the Balkans.

Despite the wide use of the live attenuated Neethling lumpy skin disease (LSD) vaccine, only limited data existed on its efficacy and effectiveness prior to the large LSD epidemic in the Balkans, which took place during 2016-2017. In addition, analysis of risk factors for the disease was hardly performed with proper control for vaccination effects and potential differences in exposure to the virus. Data from the LSD epidemics in six Balkan countries (Bulgaria, Greece, Serbia, Montenegro, Former Yugoslav Republic of Macedonia (FYROM) and Albania) affected during 2016 were analyzed to determine vaccine effectiveness (VE) and risk factors for LSD infection at the farm level. Vaccination was performed along the occurrence of the epidemics and thus vaccination status of some of the farms changed during the epidemic. To allow for this, left truncated and right censored survival analysis was used in a mixed effects Cox proportional hazard regression model to calculate VE and risk factors for LSD. The results indicated of an average VE of 79.8% (95% CI: 73.2-84.7)) in the six countries, with the lowest VE of 62.5% documented in Albania and up to VE of more than 97% as documented in Bulgaria and Serbia. Analysis of time from vaccination to development of protective immunity showed that VE mostly developed during the first 14 days after vaccination. Data from Greece showed that the vaccination adjusted hazard ratio for LSD was 5.7 higher in grazing farms compared to non-grazing farms. However, due to a difference in geographical location of grazing and non-grazing farms and higher vaccination rate in non-grazing farms, this effect can be at least partly attributed to indirect protection due to herd immunity provided by surrounding vaccinated farms.

Economic cost of lumpy skin disease outbreaks in three Balkan countries: Albania, Bulgaria and the Former Yugoslav Republic of Macedonia (2016-2017).

Lumpy skin disease (LSD) is an emerging viral disease that was detected for the first time in the Balkan Peninsula in Greece in 2015. In April 2016, there was a reoccurrence in Greece and the spread of the disease for the first time into Bulgaria, the Former Yugoslav Republic of Macedonia, Serbia, Kosovo, Albania and Montenegro. The veterinary services of the countries responded with different strategies to control the disease, mostly based on mass vaccination campaigns and diverse stamping out approaches. During 2017, the epidemic was mostly controlled except for outbreaks reported in Albania, Greece and the Former Yugoslav Republic of Macedonia. The study aims to quantify the cost of disease and control measures in three selected Balkan countries, that is, Albania, Bulgaria and the Former Yugoslav Republic of Macedonia, which were differently affected by the disease, had different animal production structures and implemented different control strategies. The total cost for the three countries was 20.9 million Euro (EUR 20.9 m), mostly incurred in 2016 (EUR 16.6 m), when the disease was spreading throughout the Balkan region. In 2017 (data until October), the cost was EUR 4.0 m, mainly due to vaccination costs. Bulgaria was the country with the highest total cost at EUR 8.6 m, followed by the Former Yugoslav Republic of Macedonia (EUR 6.7 m) and Albania (EUR 5.3 m). According to our data, the average cost per affected herd in 2016 was EUR 869, EUR 6,994 and EUR 3,071 in Albania, Bulgaria and the Former Yugoslav Republic of Macedonia, respectively. The cost per animal in the affected herds was EUR 539, 147 and 258, respectively. The results from this study are useful to understand the cost of LSD outbreaks in the region, which might contribute to improve the surveillance and control of the disease.