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IntroductionBrucellosis and Rift Valley fever (RVF) are neglected zoonotic diseases (NZD) that threaten public health, animal health, and production in resource-limited countries including Namibia.MethodsThe objective of this cross-sectional study was to determine Brucella spp. and RVFV seroprevalence in cattle at the wildlife-livestock interface in the Kabbe South constituency (Zambezi region) of Namibia. Cattle sera (n = 371) were randomly collected from 18 cattle herds in six constituency areas and tested for antibodies against Brucella [complement fixation test (CFT) and indirect enzyme-linked immunosorbent (ELISA) assay in parallel] and Rift Valley fever virus (competitive ELISA).ResultsApparent individual animal prevalence for Brucella spp. was 5.9% (95% CI: 3.95%−8.81%, 22/371) and 20.8% (95% CI: 16.9%−25.2%, 77/371) based on the CFT and I-ELISA, respectively. For RVFV, apparent and true animal prevalence were 41.0% (95% CI: 36.1%−46.0%, 152/371) and 47.6% (95% CI: 41.8%−53.6%), respectively. Animal and true prevalence of Brucella spp. based on the CFT and ELISA in parallel were 22.6% (95% CI: 18.7%−27.2%, 84/371) and 19.7% (95% CI: 15.6%−24.4%), respectively. About 10.8% (40/371) of cattle tested positive for both Brucella spp. and RVFV antibodies. Prevalence of Brucella-positive cattle herds was 83.3% (15/18). Within herd Brucella spp. seroprevalence was 0%−70%. All cattle herds tested positive for RVFV, with prevalence of 1.7% to 70%. Binomial logistic regression revealed that sex was a significant predictor (p < 0.05) for RVFV seropositivity, but not for Brucella spp. seropositivity (p > 0.05). Test agreement between CFT and I-ELISA when used for the detection of anti-Brucella antibodies was poor (k = 0.2322).DiscussionBrucella spp. and RVFV infections were prevalent in communal pastoral cattle at the human-wildlife-livestock interface in the Zambezi region suggesting a higher likelihood of occurrence of reproduction losses in cattle and zoonotic disease in humans. We recommend the enforcement of the requirements for the vaccination of heifers against brucellosis in the affected communal areas to reduce the risk of human infection. The use of One Health principles for the surveillance, prevention and control of Brucella spp. and RVFV infections can promote the effective control of these zoonotic infections at the interface.

The present study investigated the seropositivity rate of Hepatitis E virus (HEV) in domestic and working animals in Namibia, which included dogs, cats, horses, and donkeys. HEV poses a growing threat as a significant cause of human hepatitis globally and has several genotypes of varying zoonotic potential. As epidemiological data on the seroprevalence of HEV in Namibia is scarce, a serosurvey was conducted on archived serum samples of 374 dogs, 238 cats, 98 horses, and 60 donkeys collected between 2018 and 2022 from different regions, to assess the potential of these animals as sources of HEV infection. The findings revealed that 10.43% (n = 39/374) canine and 5.88% (n = 14/238) feline samples tested positive for HEV antibodies, whereas no seropositivity was detected in horses and donkeys. The study further examined the risk factors associated with HEV seropositivity, including animal sex, age, and geographical region, and noted a higher prevalence in dogs living in areas with intensive pig farming. Although there is no direct evidence indicating that these animals served as major reservoirs for HEV transmission to humans, the study underscores the importance of preventive measures to minimize contact exposure with pets considering the potential zoonotic risk, especially for susceptible risk groups. Further research is needed to explore the zoonotic potential of domestic animals and the epidemiological links between animal and human HEV transmissions in Namibia.

IntroductionThe swine sector in Africa plays an important role in local economies, contributing to poverty alleviation and community subsistence. In addition, intensive farming is progressively becoming more important in the region. Therefore, any disease affecting swine populations can have detrimental effects on local communities. Porcine Reproductive and Respiratory Syndrome (PRRS) is among the most important infectious diseases affecting swine worldwide, but information on its epidemiology in Africa is extremely limited.Material and methodsIn the present study, 147 healthy butchered pigs, originating from 15 Namibian intensive and rural farms were tested by RT-PCR and the ORF7 genes of positive samples were sequenced for further genetic characterization and phylogenetic analysis. Additionally, 55 warthogs were also evaluated using the same approach.ResultsOverall, 7 out of 147 pigs (4.76%) tested positive, all originating from 3 rural farms (with a within-herd detection frequency higher than 14%) characterized by strong epidemiological links. All industrial pig and warthog samples were negative. Sequence analysis revealed that all strains belonged to the Betaarterivirus suid1 species, previously known as PRRSV type I, and were likely imported from Europe at least 6 years ago, evolving independently thereafter. When and how the first introduction occurred could not be determined due to the absence of other African sequences for comparison.DiscussionThe present work provides the first detection and characterization of PRRSV molecular epidemiology in Namibia. Based on the present findings, the presence of the PPRSV appears marginal and limited to backyard farms. While biosecurity measures applied in industrial farms appear to be effective in preventing viral introduction, PRRSV circulation in rural settings still represents a potential threat, and considering the socio-economical implication of livestock diseases decreasing animal performances in rural areas, active monitoring should be encouraged to promptly act against emerging menaces and guarantee the welfare of local pig populations.

ABSTRACTBrucellosis is a worldwide zoonosis that is endemic in Namibia. This study estimated seroprevalence of brucellosis, and determined the presence of Brucella infection in slaughtered cattle using the genus-specific 16-23S rRNA interspacer PCR (ITS-PCR), and the species-specific AMOS-PCR. Between December 2018 and May 2019, sera (n = 304), pooled lymph nodes (n = 304), and individual spleen (n = 304) were collected from slaughtered cattle from 52 farms. Sera were tested for anti-Brucella antibodies using the Rose Bengal test (RBT), and the complement fixation test (CFT). Seroprevalence was 2.3% (7/304) (RBT) and 1.6% (5/304) (CFT). Prevalence of positive herds was 9.6% (5/52). Lymph node (n = 200) and spleen (n = 200) samples from seronegative cattle tested negative for Brucella spp. DNA on ITS-PCR, but Brucella spp. DNA was detected in lymph nodes (85.7%, 6/7) and spleen (85.7%, 6/7) from RBT positive cattle. ITS-PCR confirmed isolates from lymph node (51.4%, 4/7) and spleen (85.7%, 6/7) as Brucella spp.; while AMOS-PCR and Brucella abortus species specific (BaSS) PCR confirmed the isolates as Brucella abortus, and field strains, respectively. Provision of adequate protective gear, and the promotion of brucellosis awareness among abattoir workers is recommended to prevent zoonotic infection.

In January 2022, significant mortality was observed among Cape cormorants (Phalacrocorax capensis) on the west coast of Namibia. Samples collected were shown to be positive for H5N1 avian influenza by multiplex RT-qPCR. Full genome analysis and phylogenetic analysis identified the viruses as belonging to clade 2.3.4.4b and that it clustered with similar viruses identified in Lesotho and Botswana in 2021. This is the first genomic characterization of H5N1 viruses in Namibia and has important implications for poultry disease management and wildlife conservation in the region.

This research examined the positivity ratio of Crimean–Congo haemorrhagic fever (CCHF) antibodies in cattle and sheep within Namibia’s Omaheke region after a human disease outbreak in the same geographical area. A total of 200 samples (100 cattle and 100 sheep) were randomly collected from animals brought to two regional auction sites, and then tested using the ID Screen® CCHF Double Antigen Multi-Species Enzyme-Linked Immunosorbent Assay kit. Of the cattle samples, 36% tested positive, while 22% of the sheep samples were seropositive. The cattle had a significantly higher positivity ratio than sheep at the individual animal level (p = 0.0291). At the herd level, 62.5% of cattle herds and 45.5% of sheep flocks had at least one positive animal, but this difference was statistically insignificant (p = 0.2475). The fourteen cattle farms with at least one seropositive animal were dispersed across the Omaheke region. In contrast, the ten sheep farms with seropositive cases were predominantly situated in the southern half of the region. The study concluded that the CCHF is endemic in the Omaheke region and likely in most of Namibia, underscoring the importance of continued surveillance and preventive measures to mitigate the impact of CCHFV on animal health and potential spillover into human populations.

Dog-mediated rabies is responsible for tens of thousands of human deaths annually, and in resource-constrained settings, vaccinating dogs to control the disease at source remains challenging for various reasons. Currently, rabies elimination efforts rely on mass dog vaccination by the parenteral route. While oral rabies vaccination (ORV) of dogs is primarily considered a tool to increase herd immunity, particularly by targeting free-roaming and stray dogs, here, we are showcasing an ORV-only approach as an emergency response model. Using a third-generation vaccine and a standardized egg-flavored bait, we assessed the effectiveness and vaccination under field conditions in the Zambezi region of Namibia. During this trial, with four teams and within four working days, 3097 dogs were offered a bait, of which 88,0% were considered vaccinated. Teams managed to vaccinate, on average, over 20 dogs/h, despite using a door-to-door vaccination approach.The favorable results both in terms of bait acceptance and successful vaccination as well as field applicability and effectiveness further support the great potential of ORV in dog rabies control programmes.

Dog-mediated rabies is responsible for tens of thousands of human deaths annually, and in resource-constrained settings, vaccinating dogs to control the disease at source remains challenging. Currently, rabies elimination efforts rely on mass dog vaccination by the parenteral route. To increase the herd immunity, free-roaming and stray dogs need to be specifically addressed in the vaccination campaigns, with oral rabies vaccination (ORV) of dogs being a possible solution. Using a third-generation vaccine and a standardized egg-flavoured bait, bait uptake and vaccination was assessed under field conditions in Namibia. During this trial, both veterinary staff as well as dog owners expressed their appreciation to this approach of vaccination. Of 1,115 dogs offered a bait, 90% (n = 1,006, 95%CI:91-94) consumed the bait and 72.9% (n = 813, 95%CI:70.2-75.4) of dogs were assessed as being vaccinated by direct observation, while for 11.7% (n = 130, 95%CI:9.9-17.7) the status was recorded as "unkown" and 15.4% (n = 172, 95%CI: 13.4-17.7) were considered as being not vaccinated. Smaller dogs and dogs offered a bait with multiple other dogs had significantly higher vaccination rates, while other factors, e.g. sex, confinement status and time had no influence. The favorable results of this first large-scale field trial further support the strategic integration of ORV into dog rabies control programmes. Given the acceptance of the egg-flavored bait under various settings worldwide, ORV of dogs could become a game-changer in countries, where control strategies using parenteral vaccination alone failed to reach sufficient vaccination coverage in the dog population.

Background and Aim: African horse sickness (AHS) is a non-contagious viral disease of horses and other equids caused by an arbovirus belonging to the Reoviridae family and genus Orbivirus. AHS is an endemic disease that is responsible for the death of a high number of horses every year in Namibia. At present, there is no information on the prevalence and distribution of AHS virus (AHSV) serotypes in the different regions of Namibia. Therefore, this survey aimed to fill this knowledge gap by investigating the AHSV seroprevalence in Namibian donkeys. Materials and Methods: A total of 260 blood samples (20 samples for each region) were randomly collected from donkeys aged between 3 and 5 years. Sera were screened for AHSV-specific immunoglobulin G antibodies using a commercial competitive enzyme-linked immunosorbent assay kit and samples positive to AHSV antibodies were further tested by serum neutralization (SN) assay to evaluate the AHSV serotype-specific immune response. Results: Seroprevalence of antibodies against AHSV in Namibian donkeys was 63.5%. The AHSV prevalence was significantly higher in the northern region (64%) than in the southern region (36%). A significantly (p

The known host range of circoviruses is continuously expanding because of more intensive diagnostic activities and advanced sequencing tools. Recently, a new circovirus (penguin circovirus (PenCV)) was identified in the guano and cloacal samples collected from Adélie penguins (Pygoscelis adeliae) and chinstrap penguins (Pygoscelis antarcticus) in Antarctica. Although the virus was detected in several asymptomatic subjects, a potential association with feather disease was speculated. To investigate the occurrence and implications of PenCV in other penguin species located outside of Antarctica, a broad survey was undertaken in African penguins (Spheniscus demersus) on two islands off the southern Namibian coast. For this purpose, specific molecular biology assays were developed and validated. None of the 151 blood samples tested positive for PenCV. Several reasons could explain the lack of PenCV positive samples. African penguins and Pygoscelis species are separated by approximately 6000 km, so there is almost no opportunity for transmission. Similarly, host susceptibility to PenCV might be penguin genus-specific. Overall, the present study found no evidence of PenCV in African penguin colonies in Namibia. Further dedicated studies are required to assess the relevance of PenCV among different penguin species.

West Nile virus (WNV) is an important zoonotic Flavivirus responsible for mild fever to severe neurological disease in humans and horses. Despite the occurrence of major previous outbreaks in Namibia and the likelihood of the current endemicity of the virus, only limited investigations and monitoring activities of WNV have been performed in the country. The use of animal sentinels is a valuable approach toward investigating the infection presence in an area and to predict the potential occurrence of human outbreaks. Serological investigations in dogs hold several advantages, considering their infection susceptibility, the ease of sample handling, and the evaluation of risk factors of pet owners that share the same habit with their pets. To evaluate the usefulness of such a sero-epidemiological investigation in Namibia, a broad serosurvey was performed in 2022 that included 426 archived domestic dog samples from eight Namibian regions. Although the ELISA prevalence, indicative of Flavivirus infection, was relatively high (16.43%; 95 CI: 13.10–20.39%), the virus neutralization test confirmed only a minority of cases, highlighting a prevalence of 2.82% (95 CI: 1.47–4.90%), significantly lower than in Namibian donkeys and reports from other countries. Variables that could explain the recorded differences remain to be explored, including animal exposure, variable vector presence, distribution, and feeding preferences. The study results suggest the limited usefulness of dogs as sentinels for WNV monitoring in Namibia.

Rabies is endemic in Namibia and is present both in wildlife carnivores and domestic free-roaming dogs. The disease thus represents a challenge for public human and veterinary disease control. Namibia has implemented a national strategic plan to control rabies and the country’s activities are supported by international organizations. To this end, rabies diagnosis at the Central Veterinary Laboratory (CVL) was improved in the frame of a World Organization for Animal Health (WOAH) laboratory twinning program: from practical sampling techniques and the use of lateral flow devices to a novel universal and discriminatory quantitative real-time Reverse transcription polymerase chain reaction (RT-qPCR), which easily identify dog-associated rabies viruses. The procedures applied and the results can be used as a template to improve rabies laboratory diagnosis.

The pandemic of coronavirus disease 19 (COVID-19) has focused the attention of researchers, and especially public opinion, on the role of the human-animal-environment interface in disease emergence. At the beginning of the COVID-19 pandemic, media reports regarding the role of pets in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) caused significant concern and social anxiety. Although nowadays proven negligible in developed countries, essentially no studies have been performed in low-income African areas where companion animals are often raised differently from high income countries, and the contact patterns occurring in these scenarios could affect the epidemiological scenario. An extensive molecular biology survey was performed from March 2022 to September 2022 on Namibian dogs residing in urban and rural areas, showing a low but not negligible SARS-CoV-2 prevalence (1%; 95CI: 0.33–2.32%) of 5 out of 500. In only one instance (i.e., a 4-year-old female Labrador) was there a clear association that could be established between the infections of the owner and animal. In all other cases, no evidence of human infection could be obtained and no episodes of COVID-19 were reported by the owners. Although no consistent evidence of pet-to-pet transmission was proven in the present study, a cautionary principle suggests intensive and dedicated investigation into companion animal populations, especially when animal contact is frequent and a particularly susceptible population is present.

In late September 2017, Bwabwata National Park in Namibia experienced a sudden die-off of hippopotamuses and Cape buffalo. A multiorganizational response was initiated, involving several ministries within Namibia and the US Centers for Disease Control and Prevention. Rapid interventions resulted in zero human or livestock cases associated with this epizootic.

West Nile Virus (WNV) is a mosquito-borne virus enzootically maintained in birds. However, it can incidentally infect other species, leading to sometimes severe clinical consequences like in horses and especially human beings. Despite the topic relevance, the presence and distribution of WNV are currently unknown in Namibia. Several countries implement surveillance systems based on virus detection in birds, mosquitoes, and vertebrate species including horses. The present study aimed to fill this knowledge gap by serologically evaluating WNV exposure in Namibian donkeys, whose population is remarkably bigger than the horse one. Forty-seven out of 260 sampled animals showed neutralizing antibodies against WNV (18.07% [95% CI = 13.59–23.30%]), demonstrating its circulation in all country territory, although, with apparent regional differences. On the contrary, no association with animal age or sex could be identified. The present study demonstrates the widespread presence of WNV in Namibia as well as the practical utility and effectiveness of donkeys as sentinels for infection surveillance. Due to clinical relevance, vaccination campaigns should be considered for horses of high economic or genetic value. Additionally, the burden of WNV infection on human health should be carefully evaluated.

Understanding virus circulation in wild animals, particularly those that have contact with domestic animals, is crucial for disease management and control. In Africa, warthogs are known to be asymptomatic carriers of porcine pathogens; a recent study in Namibia has shown them to be positive for Porcine circovirus-2 (PCV-2). In this study, the same samples used for the PCV-2 investigation in Namibia were further screened for the presence of African swine fever virus (ASFV) and porcine parvovirus 1 (PPV1) by PCR. Of the 42 animals tested, 2 (4.8%) and 13 (31%) were positive for AFSV and PPV1, respectively. The two AFSV were also co-infected with PPV1. Combing the results of this study with the results of the previous PCV-2 investigation, four warthogs were shown to be co-infected with both PPV1 and PCV-2. Sequence and phylogenetic analysis revealed that the AFSV belonged to genotype (Ib) but were from different serogroups. Unexpectedly, the ASFVs from the warthogs were genetically distinct to those observed in an outbreak in the same region of Namibia that occurred less than fifteen months prior to the sampling of the warthogs. In fact, a stronger genetic relationship was observed between the warthog viruses and historical Namibian and South African ASFVs identified in 1980, 2004 and 2008. For the PPV1s, the closest relative to the Namibian PPV1 were viruses identified in wild boar in Romania in 2011. This study confirms that warthogs are carriers of porcine pathogens and the data should encourage further studies on larger populations of wild and domestic swine to more fully understand the epidemiology and transmission of viral pathogens from these species.

Domestic dogs are responsible for 99% of all cases of human rabies and thus, mass dog vaccination has been demonstrated to be the most effective approach towards the elimination of dog-mediated human rabies. Namibia demonstrated the feasibility of this approach by applying government-led strategic rabies vaccination campaigns to reduce both human and dog rabies incidences in the Northern Communal Areas of Namibia since 2016. The lessons learnt using paper-based form for data capturing and management of mass dog vaccination campaign during the pilot and roll out phase of the project (2016-2018) led to the implementation of a simple and accurate data collection tool in the second phase (2019-2022) of the rabies elimination program. In this paper, we describe the implementation of such custom-developed vaccination tracking device, i.e. the Global Alliance for Rabies Control (GARC) Data Logger (GDL), and the integration of the collected data into a website-based rabies surveillance system (Rabies Epidemiological Bulletin-REB) during 2019 and 2020 campaigns. A total of 10,037 dogs and 520 cats were vaccinated during the 2019 campaign and 13,219 dogs and 1,044 cats during the 2020 campaign. The vaccination data were recorded with the GDL and visualized via REB. Subsequent GIS-analysis using gridded population data revealed a suboptimal vaccination coverage in the great majority of grid cells (82%) with a vaccination coverage below 50%. Spatial regression analysis identified the number of schools, estimated human density, and adult dog population were associated with the vaccination performance. However, there was an inverse correlation to human densities. Nonetheless, the use of the GDL improved data capturing and monitoring capacity of the campaign, enabling the Namibian government to improve strategies for the vaccination of at-risk areas towards achieving adequate vaccination coverage which would effectively break the transmission of rabies.

Members of the genus Circovirus have been identified in several host species. While initially considered host-specific, there is growing evidence of their presence in unexpected hosts. Porcine circovirus 2 (PCV-2) is no exception, having been reported in animals belonging to different orders, including carnivores. Recently, PCV-2 was detected in domestic pigs, warthogs and antelopes in Namibia. Considering the potential contact between these populations and wild carnivores, the presence of PCV-2 was investigated in 32 black-backed jackals (Lupulella mesomelas) shot between February and July 2021 as part of predator control operations in Namibia. Two lung lymph nodes tested positive for PCV-2 by PCR, confirming the broader-than-expected PCV-2 host tropism and the susceptibility of canids. Sequence analysis demonstrated a close association between the PCV-2s identified in the jackals and PCV-2b strains collected from South African domestic pigs. Although several hypotheses regarding the source of the jackal’s infection are proposed, further studies should be performed to properly assess how PCV-2 is acquired and maintained in the wild and its potential impact on wild and domestic species.

For several years after its discovery, Porcine circovirus 2 (PCV-2) represented a major threat to the swine industry through economic losses due to the associated clinical syndromes, decreased production performances in both symptomatic and asymptomatic animals and disease management costs. Widespread vaccination administration has largely reduced the impact of this infection and represents the most effective control measure. The efficacy of vaccination is threatened by the emergence of novel (or uncommon) PCV-2 genotypes. In addition to domestic pigs, PCV-2 has been detected in several other species, a fact which could have an impact on new variant emergence and maintenance. Considering this, the present study assessed the distribution of the minor PCV-2c genotype in non-Suidae ungulates in Namibia. Red hartebeests (Alcelaphus buselaphus caama) (n = 44), kudus (Tragelaphus strepsiceros) (n = 10) and oryxes (Oryx gazella) (n = 54), whose mediastinal lymph nodes were sampled after slaughtering during the period 2019–2021, were included in the study. Two oryxes (3.7%; 95% CI = 0.45–12.75%) were PCV-2-positive by PCR. Complete genome sequence was obtained for the two samples identifying them as PCV-2c genotype. The sequences were identical and shared a high percentage of identity (~99.9%) with those recently obtained from warthogs living in the same area. The present study confirms the presence of the PCV-2c genotype (previously considered extinct) in Namibian wild animal populations and demonstrates greater than expected PCV-2 host plasticity. Because of the role these niches can have in the maintenance and evolution of minor PCV-2 genotypes, more extensive and dedicated studies should be performed to prepare authorities to promptly react to potential emerging threats from these viruses.

Between July and September 2017, samples collected from six unvaccinated chickens in Namibia were shown to be positive for infectious bursal disease virus (IBDV) by RT-PCR. Partial sequence and phylogenetic analysis of the VP1 and VP2 genes from six viruses revealed that they all belong to the very virulent pathotype (Genogroup 3) and are genetically very similar to IBDVs identified in neighbouring Zambia. This is the first molecular characterisation of IBDV in Namibia and has implications on the control and management of the disease in the country.

Rabies is a fatal zoonotic disease that causes a heavy burden on societies. Namibia, a country in southern Africa, is aiming at controlling the disease in its main reservoir, the domestic dog. To facilitate the implementation comprehensive information on the ecology and epidemiology of the disease and surveillance is of utmost importance. The study presented assesses the baseline data for both human and animal rabies surveillance in Namibia in recent times and establishes correlations with ecological and socio-economic data in order to provide an up-to-date picture on the epidemiology of rabies in Namibia. For instance, it was important to identify the main drivers in the epidemiology, and whether the control strategy by mass vaccination of dogs is undermined by cycles of rabies in wildlife. Rabies in humans was reported mainly from the Northern Communal Areas (NCAs), with a total of 113 cases from 2011 to 2017, representing an incidence of between 1.0 and 2.4 annual human rabies deaths per 100,000 inhabitants. Kavango, the region with the highest human rabies incidence was also the region with the lowest animal rabies surveillance intensity. Generally, the vast majority (77%) of dog samples originated from communal farm land, followed by urban areas (17%), while only a small fraction (3%) was submitted from freehold farm areas. In contrast, kudu and eland submissions were almost exclusively from freehold farmland (76%) and urban areas (19%), whereas the submission of cattle samples was evenly distributed among freehold farms (46%) and communal farm land (46%). The likelihood of sample submission decreased exponentially with distance to one of the two laboratories. Overall, 67% (N = 1,907) of all samples submitted tested rabies-positive, with the highest positivity rate observed in kudus (89%) and jackals (87%). The transmission cycle of rabies in dogs appears restricted to the northern communal areas of Namibia, whilst rabies in wildlife species is predominately reported from farmland in central Namibia, mostly affecting kudu (Tragelaphus strepsiceros) and livestock with a likely reservoir in wildlife canids such as jackals or bat-eared foxes. The analysis confirms the presence of two independent transmission cycles in Namibia with little geographic overlap, thus allowing for a sustainable control of rabies in dogs in the NCAs.

Porcine circovirus type 3 (PCV-3) infection is widely distributed in domestic pig populations in America, Europe, and Asia. However, no data is currently available about its presence and distribution in Africa. This study investigated the presence of PCV-3 in pigs (n = 122) in Namibia, by means of biomolecular methods. The pig samples collected (n = 122) were representative of the swine industry in Namibia, covering the major pig production facilities in the country. All of the samples tested were negative for PCV-3, and this indicated that the virus was either not present in the country or was circulating at low levels. Further studies are needed to better understand the distribution, if any, of PCV-3 in Namibia.

Large game animals play an important role as carriers and transmitters of O157:H7 and non-O157:H7 Shiga toxin-producing Escherichia coli (STEC) in nature. Fresh meat obtained from game animals has been identified as an important source of food-borne STEC infections. The aim of this study was to evaluate the incidence of the top 6 non-O157 STEC strains (serogroups O26, O45, O103, O111, O121, and O145) in Namibian game meat based on testing for stx, eae, and O-group-specific genes. Meat samples from gemsboks (Oryx gazella) (n = 75), springboks (Antidorcas marsupialis) (n = 41), greater kudus (Tragelaphus strepsiceros) (n = 5), and wildebeests (Connochaetes taurinus) (n = 5) were collected from 2 Namibian abattoirs and tested for STEC using real-time PCR techniques. Both Shiga toxin (stx) and intimin (eae) virulence genes were detected in 94 out of 126 samples (74.6%). Five of the top 6 STEC serogroup-specific genes were also detected in samples that were positive for both the stx and eae genes. The results of this study show a high incidence of non-O157 STEC O-group genes in Namibian game meat, which suggests that further scrutiny and testing may be necessary to avoid foodborne outbreaks.

The major part of the global burden of dog-mediated rabies falls on Africa and Asia, where still an estimated 60,000 people die of the disease annually. Like in many African countries, dog-mediated rabies is a major public health concern in Namibia, costing the country an estimated 242 human deaths during the past two decades, in particular in the Northern Communal Areas (NCAs). Consequently, under the “One Health” concept, the Namibian government adopted a National Rabies Control Strategy in 2015, which strives to contribute to the global goal of ending dog-mediated human rabies deaths by 2030. A key component of this strategy was the implementation a dog rabies elimination program in the NCAs in 2016, being designed as a stepwise regional rollout strategy by building on experience gained in a pilot project area. The area of implementation covers approximately 263,376 km2 and 64 constituencies, with around 1.2 million inhabitants and estimated 93,000 dogs.

La peste equina (PE) è una malattia virale non contagiosa dei solipedi trasmessa da insetti vettori appartenenti al genere Culicoides. La malattia è endemica in numerose regioni dell'Africa e passate esperienze hanno evidenziato come l'Italia sia un paese esposto alle malattie infettive emergenti, endemiche in Africa. Un'incursione del virus della PE unitamente alla presenza del vettore Culicoides potrebbero essere causa di una emergenza epidemica. Onderstepoort Biological Products (OBP) commercializza un vaccino vivo attenuato contenente 7 dei 9 sierotipi virali, i sierotipi 5 e 9 sono esclusi dal vaccino. L'uso di tali vaccini è controverso, pertanto, da diversi anni, vengono condotti studi su prodotti inattivati o ricombinanti. Poiché la ricerca sui vaccini PE è ostacolata dalla necessità di utilizzare il cavallo per la valutazione dell'immunogenicità, in un precedente esperimento è stata studiata la risposta sierologica ai sierotipi 5 e 9, in cavie e cavalli. Nelle due specie animali è stata osservata una risposta durevole e sovrapponibile. Nel presente studio sono state saggiate per un periodo di 12 mesi le risposte sierologiche ottenute in cavie e cavalli immunizzati con il vaccino inattivato formulato con il sierotipo 9. Le risposte sierologiche nelle due specie animali si sono confermate sovrapponibili. Al challenge dell'immunità i cavalli sono risultati protetti dall'infezione e dalla malattia.

African horse sickness (AHS) is a non-contagious viral disease of solipeds transmitted by Culicoides. The disease is endemic in most African countries. Past experience has shown that Italy is a country exposed to emerging infectious diseases endemic to Africa; an incursion of AHS virus together with the widespread presence of Culicoides vectors could be the cause of a serious epidemic emergency. A live attenuated vaccine containing seven of the nine viral serotypes, serotype 5 and 9 are excluded, is commercially available from Onderstepoort Biological Products. However, the use of live vaccines is a matter of endless disputes, and therefore inactivated or recombinant alternative products have been investigated over the years. Since research on AHS is hampered by the use of horses to evaluate vaccine potency, in a previous experiment serological response to serotypes 5 and 9 was assayed in guinea-pigs and horses. A durable and comparable serological response was observed in the two animal species. In the present study antibody response in horses and guinea-pigs, immunised with the inactivated-adjuvanted vaccine formulated with serotype 9, was tested over a period of 12 months. When immunity was challenged, horses were protected from infection and disease. Antibody response in horses and guinea-pigs compared favourably.

During May–July 2010 in Namibia, outbreaks of Rift Valley fever were reported to the National Veterinary Service. Analysis of animal specimens confirmed virus circulation on 7 farms. Molecular characterization showed that all outbreaks were caused by a strain of Rift Valley fever virus closely related to virus strains responsible for outbreaks in South Africa during 2009–2010.

Rabies in kudu is unique to Namibia and two major peaks in the epizootic have occurred since it was first noted in 1977. Due to the large numbers of kudu that were affected, it was suspected that horizontal transmission of rabies occurs among kudu and that rabies was being maintained independently within the Namibian kudu population - separate from canid cycles, despite geographic overlap. In this study, it was our aim to show, through phylogenetic analyses, that rabies was being maintained independently within the Namibian kudu population. We also tested, through complete genome sequencing of four rabies virus isolates from jackal and kudu, whether specific mutations occurred in the virus genome due to host adaptation. We found the separate grouping of all rabies isolates from kudu to those of any other canid species in Namibia, suggesting that rabies was being maintained independently in kudu. Additionally, we noted several mutations unique to isolates from kudu, suggesting that these mutations may be due to the adaptation of rabies to a new host. In conclusion, we show clear evidence that rabies is being maintained independently in the Namibian kudu population - a unique phenomenon with ecological and economic impacts.