Porcine epidemic diarrhea virus (PEDV) produces infection in pigs characterized by vomiting and diarrhea. PEDV is transmitted via oral-fecal and a very low oral dose is enough to infect susceptible pigs, causing devastating consequences in production. A 10,000-sow farrow-to-wean farm located in northwest Mexico was infected with PEDV. After the observation of the first clinical signs, an outbreak investigation take into place to determine the most probably source of infection. A systematic collection of samples including rectal swabs, gestation and lactation feed, surface swabs from the interior or feed bins and many points of the feed truck delivering the implicated feed was performed. Samples were tested for PEDV polymerase chain reaction (PCR). Positive PCR results showed the evidence of PEDV RNA in lactating feed, the interior walls of the feed bins and in the interior of the auger boom of the feed truck. This, connected with the location of first clinical signs point that the most probably incursion of PEDV in to this breeding herd was contaminated feed. This paper shows how feed or feed transport can be a potential source of PEDV infection in farms and highlight the importance of stablishing biosecurity programs to mitigate the risk of PEDV infections.

In this study, we introduce the vulnerability index to measure the regional ASF epidemic and present the ASF severity ratings of 31 provincial regions of China. The index is defined based on the data from investigation, national statistical yearbook and reports. The data to be used includes pig breeding, financial resources, human resources, epidemic information of ASF and price fluctuation from the 31 regions. Then we use the data envelopment analysis (DEA) model to define the vulnerability index, the relative severity values for each region which quantitatively reflect the damage degree caused by the epidemic of ASF. The method allows us to provide a systematic classification for regional vulnerability level of ASF in China. Using the index, we find that the vulnerability of the whole country is at a high level, and there is no regional aggregation phenomenon. The vulnerability level of the 31 provinces are quite different and the provinces with high vulnerability level are dispersive geographically. For the five major prevention and control zones for ASF in China, the northern region has the highest vulnerability level, while the level of eastern zoon is the lowest.

Viruses of veterinary significance such as African swine fever virus, are known to survive for extended periods in plant-based feed ingredients imported into North America. To reduce the likelihood of virus introduction, high-risk ingredients, such as oil seed meals, are stored in designated facilities for extended periods under controlled environmental conditions to minimize viral infectivity prior to use in diets. While 30 days has become a standard storage period, the required ambient temperature to inactivate viruses during this time is not known. To address the question, 1-metric ton totes of conventional soybean meal were inoculated with PRRSV 144 lineage 1C variant and SVA prior to storage for 30 days at 23.9º C, 15.5º C, or 10º C, and feeding to pigs. Virus infectivity was evaluated through detection of viral RNA in oral fluid samples, along with clinical signs. Results indicated that inactivation of both viruses occurred in soy stored at 23.9º C. In contrast, SVA infectivity was observed in soy stored at both 15.5º C and 10º C, while PRRSV 144 L1C variant infectivity was only observed in soy stored at 10º C. These results suggest that a storage period of 30-days and a temperature of 23.9º C are required to reduce the risk of virus contaminated plant-based feed ingredients, such as soybean meal.

As social media becomes an ever-increasing staple of everyday life and a growing percentage of people turn to community driven platforms as a primary source of information, the data created from these posts can provide a new source of information from which to better understand an event in near real-time. The 2018-2020 outbreak of virulent Newcastle Disease (vND) in Southern California is the third outbreak of vND in Southern California within a 50-year time span. These outbreaks are thought to be primarily driven by non-commercial poultry (i.e. backyard and game fowl) in the region. Here we employed a commercial “web crawling” tool between June of 2018 and July of 2020 which encompassed the majority of the outbreak in order to collect all available online mentions of virulent Newcastle Disease (vND) in relation to the outbreak. A total of 2,498 posts in English and Spanish were returned using a Boolean logic-based string search. While the number of posts was relatively small, their impact as measured by the number of visitors to the website and the number of people viewing the post (where provided) was much larger. Using views as a metric, Twitter was identified as the most significant source of comments over blogs, forums and other news sites. Posts with negative sentiment were found to have a larger audience relative to posts with a positive sentiment. In addition, posts with negative sentiment peaked in May of 2019 which preceded the formation of the anti-depopulation group Save Our Birds (SOB). As the usage and impact of social media grows, the ability to utilize tools to analyze social media may improve both response and outreach-based strategies for various disease outbreaks including vND in Southern California which has a large non-commercial poultry population.

Mongolia and Eastern Siberia, Russia are border regions in Asia with high incidence of tuberculosis (TB). In this study, we aimed to investigate MDR -TB transborder transmission with a focus on endemic and epidemic Mycobacterium tuberculosis clones and drug resistance patterns. M. tuberculosis strains (291 from Mongolia and 754 from Russia) were collected within cross-sectional population-based surveys in 2010-2016. DNA was genotyped in 24 MIRU-VNTR loci and by PCR testing of the key SNP markers to discriminate within Beijing genotype. In total, 1045 isolates were divided into 435 MIRU-types that were assigned to Lineage 2 (Beijing isolates) and Lineage 4 (Ural, Haarlem, Latin-American-Mediterranean [LAM], S, and unclassified isolates). Beijing genotype was dominant in both countries, but most of Russian and all Mongolian Beijing strains belonged to different subtypes of the modern Beijing sublineage with only negligible overlap between the two countries. In particular, the Beijing types #342-32, #3819-32, #1773-32 (Asian African 2 group) were found only in Mongolia. LAM was the most common non-Beijing genotype (11.0% in Mongolia and 14.7% in Russia) and its isolates mostly belonged to LAM-RUS branch. MDR rate was higher in Russia compared to Mongolia among newly diagnosed patients: 29.4% versus 4.2% (p < 0.001) but similar and high in the retreatment subgroups (65.8% and 67.4%, respectively). In Russian collection, a higher MDR rate was observed in (i) Beijing compared to non-Beijing (47.5% versus 38.8%, p = 0.03), (ii) Beijing B0/W148 subtype compared to Beijing Central Asian/Russian subtype (64.5% versus 39.3%, p <0.001). In Mongolia, MDR rate was similar in Beijing (29.7%) and non-Beijing (27.5%) genotypes. In conclusion, population structures of the Beijing genotype in Mongolia and Russian borderline regions differ significantly including specific patterns of drug resistance. In contrast, largely overlapping LAM subtypes may correlate with historical endemic circulation of the LAM-RUS branch in Northern Eurasia.