Monitoring of African Swine Fever in the Wild Boar Population of the Most Recent Endemic Area of Spain

Wild boars are natural hosts for African swine fever (ASF). The ASF virus (ASFV) can persist for long periods in the environment, such as in ticks and contaminated products, which may be sources of infection for wild boar populations. African swine fever was eradicated in domestic pig populations in Spain in 1995, after 35 years of significant effort. To determine whether ASFV can persist in wild boar hosts after it has been eradicated from domestic pigs and to study the role of wild boar in helping ASFV persist in the environment, we checked for the presence of ASFV in wild boars in Doñana National Park, one of the largest natural habitats of wild boar in Spain and one of the last areas where ASF was endemic prior its eradication. Samples from 158 animals collected between 2006 and 2010 were analysed using serological and nucleic acid‐based diagnostic techniques recommended by the World Organization for Animal Health (OIE). None of the samples was found to be positive. These results confirm the absence of disease in wildlife in what was once one of the areas most affected by ASF in Spain, and they suggest that wild boars play a limited role in ASFV persistence. These results confirm that ASFV cannot persist in isolated wild boar populations for long periods of time without the interaction of other factors such as re‐infection by contact with domestic pigs or by feeding on contaminated swill.     

Detection of African Swine Fever Antibodies in Experimental and Field Samples from the Russian Federation: Implications for Control

African swine fever (ASF) re‐entered in Europe in 2007 by Georgia rapidly affecting neighbouring countries. Since then, ASF has caused severe problems to the Russian Federation (RF) and spread to Northern and Western regions, including Ukraine (2012 and 2014) and Belarus (2013). At the beginning of 2014, dead wild boars were found in Lithuania and Poland. Several outbreaks have been later notified in the European Union(EU), affecting domestic pigs and wild boar of Latvia, Lithuania and Poland, and also wild boar in Estonia, causing major problems for the EU pig sector. Some studies have been performed with this ASFV isolate, revealing that it belongs to genotype II and causes an acute form of the disease. However, few data are available about the presence of antibodies in field and experimental samples from the affected area. This study analysed samples from experimental infections with ASFV isolated from the RF in 2013 (74 sera and 3 tissue exudates), and field samples from the RF from 2013 to 2014 (266 samples, including 32 and 7 tissue exudates from domestic pigs and wild boar, respectively). All samples were tested by a commercial ELISA and, some of them (79), also by immunochromatographic tests. Positive and doubtful samples were confirmed by immunoblotting test. Positive results were found in experimental and field samples, which confirm the presence of antibodies against ASFV in the RF. Antibodies were detected in animals inoculated with three different ASFV isolates, with some differences found among them. Only a small percentage of field samples was positive for ASF antibodies (3.7%), in agreement with other observations that reported a high virulence for the ASFV isolates in the area. These results confirm the potential presence of survivor animals that should be considered in affected areas to help design effective control and eradication plans against ASF.     

Experimental Infection of Domestic Pigs with African Swine Fever Virus Lithuania 2014 Genotype II Field Isolate

An experimental infection was conducted to evaluate horizontal transmission, clinical, virological and humoral response induced in domestic pigs infected with African swine fever (ASF) genotype II virus circulating in 2014 into the European Union (EU). Ten naive pigs were placed in contact with eight pigs experimentally inoculated with the Lithuanian LT14/1490 ASF virus (ASFV) responsible for the first ASF case detected in wild boar in Lithuania in January 2014. Clinical examination and rectal temperature were recorded each day. Blood sampling from every animal was carried out twice weekly. Blood samples were examined for presence of ASF virus‐specific antibodies and for determining the ASFV viral load. From the obtained results, it was concluded that the Lithuanian ASFV induced an acute disease which resulted in 94, 5% mortality. The disease was easily detected by real‐time PCR prior to the onset of clinical signs and 33% of the animals seroconverted. All findings were in accordance with observations previously made in domestic pigs and wild boar when infected with ASF genotype II viruses characterized by a high virulence. One in‐contact pig remained asymptomatic and survived the infection. The role of such animals in virus transmission would need further investigation.     

First Detection of Antibodies Against African Swine Fever Virus in Faeces Samples

African swine fever (ASF) is a viral, highly lethal haemorrhagic disease of swine with no available vaccine or effective treatment. Introduction of ASF into a country triggers immediate restriction measures that cause significant economic losses and threatens spread to neighbouring countries. Wild boar populations have been recently assigned an essential role in the spread of African swine fever virus (ASFV) to European countries. Therefore, effective surveillance and monitoring of wild boar populations is required, but sampling wild boar is logistically challenging and expensive. This study assessed the feasibility of detecting antibodies against ASFV in faeces for later implementation in surveillance and control programmes. Two groups of pigs were experimentally infected with an attenuated ASFV isolate Ken05, and blood, oral fluid and faecal samples were tested for the presence of viral DNA using quantitative real‐time polymerase chain reaction (qPCR) to monitor infection progress. Faecal samples were analysed using two indirect enzyme‐linked immunosorbent assays (ELISAs) based on semipurified viral protein (vp) 72 or purified recombinant vp30 expressed in mammalian cells. Faecal samples from 9 of 10 pigs with non‐haemorrhagic diarrhoea tested positive for antibodies against ASFV using the two ELISA tests that showed a positive correlation. The serum sample results from the two indirect ELISAs were compared against results from the reference ELISA technique and the immunoperoxidase test. Our findings indicate the feasibility of faecal sampling for detecting anti‐ASFV antibodies, which may provide a practical non‐invasive alternative for sampling wild boar populations. In conclusion, the application of these ELISA tests to faecal field samples could be particularly useful to screen for the presence of ASF in field conditions.     

Assessment of interactions between African swine fever virus,bushpigs (Potamochoerus larvatus), Ornithodoros ticks and domestic pigs in north‐western Madagascar

Since its introduction in Madagascar in 1998, African swine fever (ASF) has severely affected national pig production and persists as a common disease in that country. Two of its natural hosts in the African continent, the bushpig (Potamochoerus larvatus) and tick vectors of the Ornithodoros moubata complex, are reported in west and central regions of the island. However, their role in the maintenance and transmission of the virus has been insufficiently studied. In this work, we tried to assess their potential role in the epidemiology of the disease in Madagascar, by assessing the levels of interaction between (i) ASF virus (ASFV) and bushpigs and (ii) between soft ticks and domestic and wild suids in north‐western Madagascar. Twenty‐seven sera and 35 tissue samples from bushpigs were collected and analysed for the presence of anti‐ASF antibodies and viral DNA. In addition, the sera from 27 bushpigs and 126 domestic pigs were analysed with an ELISA test for the detection of antibodies against salivary antigens from Ornithodoros ticks. No circulation of ASFV or anti‐ASFV antibodies nor anti‐tick antibodies were detected in bushpigs. However, seven of the domestic pig sera (5.6% of the total sample population) were antibody positive for O. moubata antigens. The probability of freedom from ASFV in the bushpig population using Bayesian statistical methods ranged between 73% and 84%. The probabilities of absence of anti‐tick antibodies in domestic and wild pigs were estimated at 63% and 71%, respectively. These preliminary results suggest that bushpigs are unlikely to play a significant role in the maintenance and transmission of ASFV in Madagascar. Nevertheless, further ASFV surveys are needed on that species to confirm this assumption. In addition, the presence of antibodies against O. moubata in domestic pigs suggests that soft ticks may be able to maintain ASFV within a domestic pig cycle in areas of Madagascar where they remain present.     

Assessing the Risk of African Swine Fever Introduction into the European Union by Wild Boar

The presence of African swine fever (ASF) in the Caucasus region and Russian Federation has increased concerns that wild boars may introduce the ASF virus into the European Union (EU). This study describes a semi‐quantitative approach for evaluating the risk of ASF introduction into the EU by wild boar movements based on the following risk estimators: the susceptible population of (1) wild boars and (2) domestic pigs in the country of origin; the outbreak density in (3) wild boars and (4) domestic pigs in the countries of origin, the (5) suitable habitat for wild boars along the EU border; and the distance between the EU border and the nearest ASF outbreak in (6) wild boars or (7) domestic pigs. Sensitivity analysis was performed to identify the most influential risk estimators. The highest risk was found to be concentrated in Finland, Romania, Latvia and Poland, and wild boar habitat and outbreak density were the two most important risk estimators. Animal health authorities in at‐risk countries should be aware of these risk estimators and should communicate closely with wild boar hunters and pig farmers to rapidly detect and control ASF.     

Attenuated and non‐haemadsorbing (non‐HAD) genotype II African swine fever virus (ASFV) isolated in Europe,Latvia 2017

A non‐haemadsorbing (non‐HAD) ASF virus (ASFV) genotype II, namely Lv17/WB/Rie1, was isolated from a hunted wild boar in Latvia in 2017. Domestic pigs experimentally infected with the non‐HAD ASFV developed a nonspecific or subclinical form of the disease. Two months later, these animals were fully protected when exposed to other domestic pigs infected with a related virulent HAD genotype II ASFV.     

Understanding African Swine Fever infection dynamics in Sardinia using a spatially explicit transmission model in domestic pig farms

African swine fever virus (ASFV ) has been endemic in Sardinia since 1978, resulting in severe losses for local pig producers and creating important problems for the island's veterinary authorities. This study used a spatially explicit stochastic transmission model followed by two regression models to investigate the dynamics of ASFV spread amongst domestic pig farms, to identify geographic areas at highest risk and determine the role of different susceptible pig populations (registered domestic pigs, non‐registered domestic pigs [brado ] and wild boar) in ASF occurrence. We simulated transmission within and between farms using an adapted version of the previously described model known as Be‐FAST . Results from the model revealed a generally low diffusion of ASF in Sardinia, with only 24% of the simulations resulting in disease spread, and for each simulated outbreak on average only four farms and 66 pigs were affected. Overall, local spread (indirect transmission between farms within a 2 km radius through fomites) was the most common route of transmission, being responsible for 98.6% of secondary cases. The risk of ASF occurrence for each domestic pig farm was estimated from the spread model results and integrated in two regression models together with available data for brado and wild boar populations. There was a significant association between the density of all three populations (domestic pigs, brado , and wild boar) and ASF occurrence in Sardinia. The most significant risk factors were the high densities of brado (OR = 2.2) and wild boar (OR = 2.1). The results of both analyses demonstrated that ASF epidemiology and infection dynamics in Sardinia create a complex and multifactorial disease situation, where all susceptible populations play an important role. To stop ASF transmission in Sardinia, three main factors (improving biosecurity on domestic pig farms, eliminating brado practices and better management of wild boars) need to be addressed.     

Genetically similar hepatitis E virus strains infect both humans and wild boars in the Barcelona area,Spain, and Sweden

Hepatitis E virus (HEV) is a hepatotropic virus, endemic in Europe where it infects humans and animals, with domestic pigs and wild boars as main reservoirs. The number of HEV‐infected cases with unknown source of infection increases in Europe. There are human HEV strains genetically similar to viruses from domestic pigs, and zoonotic transmission via consumption of uncooked pork meat has been shown. Due to continuous growth of the wild boar populations in Europe, another route may be through direct or indirect contacts with wild boars. In the Collserola Natural Park near Barcelona, Spain, the wild boars have spread into Barcelona city. In Sweden, they are entering into farmlands and villages. To investigate the prevalence of HEV and the risk for zoonotic transmissions, the presence of antibodies against HEV and HEV RNA were analysed in serum and faecal samples from 398 wild boars, 264 from Spain and 134 from Sweden and in sera from 48 Swedish patients with HEV infection without known source of infection. Anti‐HEV was more commonly found in Spanish wild boars (59% vs. 8%; p < 0.0001) while HEV RNA had similar prevalence (20% in Spanish vs. 15% in Swedish wild boars). Seven Swedish and three Spanish wild boars were infected with subtype 3f, and nine Spanish with subtype 3c/i. There were three clades in the phylogenetic tree formed by strains from wild boars and domestic pigs; another four clades were formed by strains from humans and wild boars. One strain from a Spanish wild boar was similar to strains from chronically infected humans. The high prevalence of HEV infections among wild boars and the similarity between wild boar HEV strains and those from humans and domestic pigs indicate that zoonotic transmission from wild boar may be more common than previously anticipated, which may develop into public health concern.     

The evolution of African swine fever virus in Sardinia (1978–2014) as revealed by whole‐genome sequencing and comparative analysis

African swine fever (ASF) is a highly contagious and lethal viral disease of pigs and wild boars, which is enzootic in many African countries and on the Italian island of Sardinia, where it has been present since 1978. Previous genetic analyses of Sardinian ASF virus (ASFV) isolates have revealed that they all belong to p72 genotype I, with only minor sequence variations. However, these studies examined only a few selected genes. To distinguish between these closely related isolates and better investigate ASFV evolution in Sardinia, we sequenced the complete genomes of 12 Sardinian ASFV isolates collected between 1978 and 2012, and compared them with 47/Ss/2008 and 26544/OG10. Most of the observed changes occurred in a time‐dependent manner; however, their biological significance remains unclear. As a whole, our results demonstrate the remarkable genetic stability of these strains, supporting a single‐source introduction of the virus.     

The African swine fever virus isolate Belgium 2018/1 shows high virulence in European wild boar

African swine fever (ASF) is one of the most important and complex viral diseases in domestic pigs and wild boar. Over the last decade, the disease has spread to several European and Asian countries and is now one of the major threats to profitable pig production worldwide. One of the more recently affected western countries is Belgium. To date, only wild boar are affected in a rather defined area in the Luxembourg region close to France, Luxembourg and Germany. While detailed sequence analyses were recently performed, biological characterization was still pending. Here, we report on the experimental inoculation of four sub‐adult wild boar to further characterize the virus and its distribution in different tissues. After oronasal inoculation with the virus strain ‘Belgium 2018/1’, all animals developed an acute and severe disease course with typical pathomorphological and histopathological lesions. Organs and blood samples were positive in qPCR, haemadsorption test and antigen lateral flow devices (LFD). Virus and viral genome were also detected in genitals and accessory sex glands of two boars. There were no antibodies detectable in commercial antibody ELISAs, antibody LFDs and indirect immunoperoxidase tests. Thus, the genotype II ASF virus isolate ‘Belgium 2018/1’ showed a highly virulent phenotype in European wild boar similar to parental viruses like Armenia 2007 and other previously characterized ASFV strains. The study also provided a large set of well‐characterized sample materials for test validation and assay harmonization.     

Co‐circulation of multiple genotypes of African swine fever viruses among domestic pigs in Zambia (2013–2015)

During 2013–2015, several and severe outbreaks of African swine fever (ASF ) affected domestic pigs in six provinces of Zambia. Genetic characterization of ASF viruses (ASFV s) using standardized genotyping procedures revealed that genotypes I, II and XIV were associated with these outbreaks. Molecular and epidemiological data suggest that genotype II ASFV (Georgia 2007/1‐like) detected in Northern Province of Zambia may have been introduced from neighbouring Tanzania. Also, a genotype II virus detected in Eastern Province of Zambia showed a p54 phylogenetic relationship that was inconsistent with that of p72, underscoring the genetic variability of ASFV s. While it appears genotype II viruses detected in Zambia arose from a domestic pig cycle, genotypes I and XIV possibly emerged from a sylvatic cycle. Overall, this study demonstrates the co‐circulation of multiple genotypes of ASFV s, involvement of both the sylvatic and domestic pig cycle in ASF outbreaks in Zambia and possible trans‐boundary spread of the disease in south‐eastern Africa. Indeed, while there is need for regional or international concerted efforts in the control of ASF , understanding pig marketing practices, pig population dynamics, pig housing and rearing systems and community engagement will be important considerations when designing future prevention and control strategies of this disease in Zambia.     

Antigenic regions of African swine fever virus phosphoprotein P30

African swine fever (ASF) is one of the most complex and lethally haemorrhagic viral diseases of swine, affecting all breeds and ages of pigs. In the absence of ASF vaccines, reliable laboratory diagnosis and restricted biosecurity are critical for disease prevention and control. A detection of ASF‐specific antibodies in an unvaccinated pig is a good marker for the diagnosis of ASF. The immunoperoxidase test (IPT) is a sensitive test for detecting ASF virus (ASFV) antibodies. However, due to the complexity of the procedure, the IPT is only suitable to be used as a confirmatory test. The ASFV p30 protein‐based enzyme‐linked immunosorbent assay (ELISA) is widely used for ASFV antibody screening, but the sensitivity is not comparable to the IPT. It is essential to have a better understanding of the antigenic properties of ASFV p30 to improve p30‐based serologic tests. In this study, we developed a panel of 21 monoclonal antibodies (mAbs) against ASFV p30. With 14 out of the 21 mAbs, we defined 4 antigenic regions that contain at least 4 linear epitopes. Nine of the 14 mAbs mapped to antigenic regions 3 and 4 reacted with p30 in all serologic methods tested in this study, such as indirect immunofluorescence assay (IFA), ELISA and Western blot. The antigenic regions 3 and 4 are highly conserved and immunodominant in host antibody response. These mAbs and the defined p30 antigenic regions 3 and 4 provide valuable tools for the development and improvement of ASF serologic assays.     

Symptomatic and asymptomatic cases of African swine fever in Tanzania

African swine fever (ASF) is an acute, highly contagious and deadly viral haemorrhagic disease of domestic pigs caused by African swine fever virus (ASFV). In ASF endemic countries, there are an increasing number of reports on circulating ASFV strains with different levels of virulence causing a broad range of clinical symptoms in susceptible animals. Tanzania, where ASFV is endemic since 2001, recorded several outbreaks including symptomatic and asymptomatic cases between 2015 and 2017. We collected 35 clinical samples from four outbreaks for diagnostic confirmation and sequenced the partial B646L (p72), the full E183L (p54) gene, the central variable region of the B602L gene and the intergenic region between the I73R and I329L genes to characterize molecularly the new ASFV isolates and analyse their relatedness with previously reported Tanzanian and foreign isolates. We detected ASFV in 21 samples, 15 from symptomatic and six from asymptomatic pigs. Phylogenetic analyses based on the partial p72 gene and the complete p54 (E183L) genes revealed that the ASFVs in samples from symptomatic pigs belonged to genotypes II and those in samples from asymptomatic pigs belonged to genotype IX. The CVR profiles of the p72 genotype II and genotype IX isolates differed between each other and from previously published Tanzanian sequences. The sequence analysis of the intergenic region between the I73R and I329L for the 2017 genotype II isolates showed the absence of one GGAATATATA motif in those isolates. This study showed the simultaneous circulation of two different ASFV genotypes with different levels of pathogenicity in Tanzania. Since the existence of sub‐clinically infected pigs may contribute to the persistence of the virus, our findings suggest continuous surveillance and characterization of ASFV isolates in disease‐endemic regions.     

Spatio‐temporal Analysis of African Swine Fever in Sardinia (2012–2014): Trends in Domestic Pigs and Wild Boar

African swine fever (ASF) is a notifiable viral disease affecting domestic pigs and wild boars that has been endemic in Sardinia since 1978. Several risk factors complicate the control of ASF in Sardinia: generally poor level of biosecurity, traditional breeding practices, illegal behaviour in movements and feeding of pigs, and sporadic occurrence of long‐term carriers. A previous study describes the disease in Sardinia during 1978–2013. The aim of this study was to gain more in‐depth knowledge of the spatio‐temporal pattern of ASF in Sardinia during 2012 to May 2014, comparing patterns of occurrence in domestic pigs and wild boar and identifying areas of local transmission. African swine fever notifications were studied considering seasonality, spatial autocorrelation, spatial point pattern and spatio‐temporal clusters. Results showed differences in temporal and spatial pattern of wild boar and domestic pig notifications. The peak in wild boar notifications (October 2013 to February 2014) occurred six months after than in domestic pig (May to early summer 2013). Notifications of cases in both host species tended to be clustered, with a maximum significant distance of spatial association of 15 and 25 km in domestic pigs and wild boars, respectively. Five clusters for local ASF transmission were identified for domestic pigs, with a mean radius and duration of 4 km (3–9 km) and 38 days (6–55 days), respectively. Any wild boar clusters were found. The apparently secondary role of wild boar in ASF spread in Sardinia could be explained by certain socio‐economic factors (illegal free‐range pig breeding or the mingling of herds. The lack of effectiveness of previous surveillance and control programmes reveals the necessity of employing a new approach). Results present here provide better knowledge of the dynamics of ASF in Sardinia, which could be used in a more comprehensive risk analysis necessary to introduce a new approach in the eradication strategy.     

African swine fever virus survival in buried wild boar carcasses

Since the first introduction of African swine fever (ASF) into the European wild boar population in 1957, the question of virus survival in carcasses of animals that succumbed to the disease has been discussed. The causative African swine fever virus (ASFV) is known to be very stable in the environment. Thus, carcasses of infected wild boar could play a major role as ASFV reservoir and thereby help to locally maintain and spread the disease in wild boar populations. To minimize this risk, removal of wild boar carcasses in ASF affected areas is regarded to be crucial for effective disease control. If removal is not feasible, carcasses are usually disposed by burial on the spot to avoid direct contact of wild boar to the infection source. In this study, carcasses of ASFV infected wild boar buried in Lithuania at different time points and locations have been excavated and retested for the presence of infectious ASFV by in vitro assays and for viral genome by qPCR. Soil samples potentially contaminated by body fluids have been additionally tested for viral genome. In seventeen out of twenty burial sites, samples of excavated carcasses were positive for ASFV genome. However, in none of the carcass samples ASFV could be isolated. On seven sites soil samples contained ASF viral DNA. These results unexpectedly negate the long‐term persistence of infectious ASFV in wild boar carcasses independent from the burial time. In this context, sensitivity of ASFV isolation from carcass samples versus susceptibility of animals and doses needed for oral inoculation has to be further investigated. Furthermore, research is required to consider alternative ASF infection sources and drivers in the infection cycle among wild boar.     

Surveillance and control of African Swine Fever in free‐ranging pigs in Sardinia

African swine fever (ASF) is a notifiable infectious disease, caused by the ASF virus (ASFV), which is a DNA virus belonging to the family Asfarviridae, genus Asfivirus. This disease has gained importance in the last decade after its spread in several countries in Eastern and Central Europe, and more recently, in China. Despite the efforts made to eradicate it, ASF is still present on the Mediterranean island of Sardinia (Italy) and has been since 1978. ASF risk factors on the island have been analysed in previous studies; the role of free‐ranging pigs in virus persistence has been suggested, but has not been fully elucidated. The most recent eradication plan provides more stringent measures to combat free‐ranging pigs and any kind of illegality in the pig sector. From December 2017 to June 2018, a total of 29 depopulation actions were performed in 13 municipalities in central Sardinia, during which 2,281 free‐ranging pigs were culled and more than 50% of them were tested for ASFV and antibody presence (1,218 and 1,416, respectively). A total of 651 pigs were seropositive, with a mean seroprevalence of 53.4% (CI 95% = 50.6–56.3), and 38 were ASFV positive (virus prevalence = 2.6%; CI 95% = 2.1–3.0). To the best of our knowledge, the present study is the first to provide a complete evaluation of this millennial system of pig farming and ASFV prevalence in free‐ranging pigs. Furthermore, it has emphasised the necessity of combining the maintenance of an epidemiological surveillance program with continuous education of farmers and other people involved in pig husbandry, based on cultural and economic aspects.     

Genetic characterization of African swine fever virus isolates from soft ticks at the wildlife/domestic interface in Mozambique and identification of a novel genotype

African swine fever virus (ASFV ) is one of the most threatening infectious diseases of pigs. There are not sufficient data to indicate the importance of the sylvatic cycle in the spread and maintenance of the disease locally and potentially, globally. To assess the capacity to maintain ASF in the environment, we investigated the presence of soft tickreservoirs of ASFV in Gorongosa National Park (GNP ) and its surrounding villages. A total of 1,658 soft ticks were recovered from warthog burrows and pig pens at the wildlife/livestock interface of the GNP and viral DNA was confirmed by nested PCR in 19% of Ornithodoros porcinus porcinus and 15% of O. p. domesticus . However, isolation of ASFV was only achieved in approximately 50% of the PCR ‐positive samples with nineteen haemadsorbing virus isolates recovered. These were genotyped using a combination of partial sequencing of the B646L gene (p72 ) and analysis of the central variable region (CVR ) of the B602L gene. Eleven isolates were classified as belonging to genotype II and homologous to contemporary isolates from southern Africa, the Indian Ocean and eastern Europe. Three isolates grouped within genotype V and were similar to previous isolates from Mozambique and Malawi. The remaining five isolates constituted a new, previously unidentified genotype, designated genotype XXIV . This work confirms for the first time that the virus currently circulating in eastern Europe is likely to have a wildlife origin, and that the large diversity of ASFV maintained in wildlife areas can act as a permanent sources of different strains for the domestic pig value chain in Mozambique and beyond its boundaries. Their genetic similarity to ASFV strains currently spreading across Europe justifies the need to continue studying the sylvatic cycle in this African country and other parts of southern Africa in order to identify potential hot spots of ASF emergence and target surveillance and control efforts.     

Re‐emergence of genotype I of African swine fever virus in Ivory Coast

In July 2014, an outbreak of severe haemorrhagic disease in a domestic pig population, was reported in San‐Pedro, the second seaport city of Ivory Coast. Animals of all age groups developed clinical signs consistent with African swine fever (ASF). Tissue and serum samples from dead pigs were sent to the laboratory for diagnostic confirmation and molecular characterization based on the partial B646L (p72), the full E183L (p54) gene and the central variable region of the B602L gene. The PCR results confirmed the outbreak of ASF. Phylogenetic analyses based on p72 and p54 sequences showed that the San‐Pedro 2014 outbreak virus strain belongs to p72 genotype I. The Analysis of the tetrameric amino acid repeat regions of the B602L gene showed two repeat signatures which differ by an extra A = CAST in the second signature. The ASFV sequence of the San‐Pedro 2014 outbreak strain is closely related to historical and recent ASFV strains collected in Angola and Cameroon whose ships have repeatedly visited the seaport of San‐Pedro from March to June 2014. The 2014 viruses are distinct from the strains involved in the previous ASF wave in 1996 in Ivory Coast.     

Identification of a New Genotype of African Swine Fever Virus in Domestic Pigs from Ethiopia

African swine fever (ASF) is an important emerging transboundary animal disease (TAD), which currently has an impact on many countries in Africa, Eastern Europe, the Caucasus and the Russian Federation. The current situation in Europe shows the ability of the virus to rapidly spread, which stands to threaten the global swine industry. At present, there is no viable vaccine to minimize spread of the disease and stamping out is the main source of control. In February 2011, Ethiopia had reported its first suspected outbreaks of ASF. Genomic analyses of the collected ASF virus (ASFV) strains were undertaken using 23 tissue samples collected from domestic swine in Ethiopia from 2011 to 2014. The analysis of Ethiopian ASFVs partial p72 gene sequence showed the identification of a new genotype, genotype XXIII, that shares a common ancestor with genotypes IX and X, which comprise isolates circulating in Eastern African countries and the Republic of Congo. Analysis of the p54 gene also followed the p72 pattern and the deduced amino acid sequence of the central variable region (CVR) of the B602L gene showed novel tetramer repeats not previously characterized.