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James Muleme,1,2 Clovice Kankya,2 Musso Munyeme,3 David Musoke,1 John C Ssempebwa,1 John Bosco Isunju,1 Rogers Wambi,2,4 Bonny Enock Balugaba,1 Tahalu Sekulima,5 Richard K Mugambe,1 Simeon Cadmus,6 Henry M Kajumbula7 1Department of Disease Control and Environmental Health, Makerere University School of Public Health, Kampala, Uganda; 2Department of Biosecurity Ecosystems and Veterinary Public Health, Makerere University College of Veterinary Medicine Animal Resources and Biosecurity, Kampala, Uganda; 3Department of Disease Control, School of Veterinary Medicine, University of Zambia, Lusaka, Zambia; 4Department of Clinical Laboratory, Mulago National Referral Hospital, Kampala, Uganda; 5Department of Biotechnical and Diagnostic Sciences, Veterinary Microbiology Research Laboratory, College of Veterinary Medicine, Animal Resources and Biosecurity, Kampala, Uganda; 6Department of Veterinary Public Health and Preventive Medicine, Center for Control and Prevention of Zoonoses, Faculty of Veterinary Medicine, University of Ibadan, Ibadan, Nigeria; 7Department of Medical Microbiology, Makerere University College of Health Sciences, Kampala, UgandaCorrespondence: James Muleme, Email mulemej@gmail.comBackground: The occurrence of extended spectrum beta-lactamase (ESBL) producing bacteria such as Escherichia coli has increasingly become recognized beyond hospital settings. Resistance to other types of antibiotics limits treatment options while the existence of such bacteria among humans, animals, and the environment is suggestive of potential zoonotic and reverse-zoonotic transmission. This study aimed to establish the antibiotic susceptibility profiles of the ESBL-producing Escherichia coli (ESBL-EC) from human, animal, and environmental isolates obtained among farming households within Wakiso district using a One Health approach.Methods: A total of 100 ESBL-EC isolates from humans 35/100 (35%), animals 56/100 (56%), and the environment 9/100 (9%) were tested for susceptibi

Transboundary pathogens of goats present significant constraints to the livelihoods of millions of farmers in countries such as Zambia. Consequently, this study aimed to investigate the seroprevalence of Mycoplasma capricolum subsp. capripneumoniae (Mccp), foot and mouth disease virus (FMDV), Brucella spp., Crimean Congo haemorrhagic fever virus (CCHFV), and Rift Valley fever virus (RVFV) in Zambian goats. Another aim was to identify associations between seroprevalence and different predictor variables, such as trade and border proximity. From September to October 2019, 962 serum samples were collected from goats in seven Zambian districts, four of which have an international border while the remaining three do not. A questionnaire survey was conducted with each household, focusing on trade routines, management strategies and herd disease history. Animal-level seroprevalence adjusted for herd-level clustering was 8.2 % (95 % confidence interval [CI] 7.5-9.0) for Mccp, 12.9% (95% CI 12.0-13.7) for FMDV, 13.0 % (95% CI 12.1-13.9) for Brucella spp., 3.3 % (95% CI 2.8-3.7) for CCHFV, and 0.4 % (95 % CI 0.3-0.7) for RVFV. The association between herd-level seroprevalence and border proximity and trade appeared negligible, with the exception of selling goats at least twice a year which was identified as a potential risk factor for Brucella spp. (OR 4.1, 95 % CI 1.1-16.0, p = 0.040). In addition, a positive association between herd-level seroprevalence of FMDV and a herd size of 21 goats or more (OR 3.3, 95 % CI 1.0-11.1, p = 0.049) was detected. Also, positive associations between animal-level seroprevalence of Brucella spp. and increasing age (OR 7.7, 95 % CI 1.5-40.7, p = 0.016), and CCHFV and keeping pigs in the household (OR 2.7, 95 % CI 1.0-7.1, p = 0.044), were found. For FMDV (OR 3.8, 95 % CI 1.4-10.9, p = 0.011) and Brucella spp. (OR 4.5, 95 % CI 1.2-17.3, p = 0.031) on the other hand, animal-level seroprevalence was significantly higher in households without pigs

Transboundary pathogens pose a threat to livelihood security in countries such as Zambia and Tanzania. This study aimed to investigate the seroprevalence of peste des petits ruminants virus (PPRV), foot and mouth disease virus (FMDV), sheep and goat pox virus (SGPV), Rift Valley fever virus (RVFV) and Brucella spp. in sheep and goats along the Tanzania-Zambia border. Another aim was to assess the association between certain predictor variables and seroprevalence, focusing on trade and proximity to an international border, to a town and to the Tanzania-Zambia highway. During September-October 2018, 486 serum samples from small ruminants in Zambia and 491 in Tanzania were collected and analyzed using enzyme-linked immunosorbent assays (ELISA). A questionnaire focused on management strategies was administered to each household. The animal-level seroprevalence in Zambia was 0.21% [95% confidence interval (CI) (0.01-1.14) for PPRV, 1.03% (95% CI 0.33-2.39) for FMDV, 0% (95% CI 0-0.76) for SGPV, 2.26% (95% CI 1.14-4.01) for RVFV and 1.65% (95% CI 0.71-3.22) for Brucella spp.]. In Tanzania, animal-level seroprevalence was 2.85% (95% CI 1.57-4.74) for PPRV, 16.9% (95% CI 13.7-20.5) for FMDV, 0.20% (95% CI 0.01-1.13) for SGPV, 3.26% (95% CI 1.87-5.24) for RVFV and 20.0% (95% CI 14.5-26.5) for Brucella spp. For PPRV (OR 6.83, 95% CI 1.37-34.0, p = 0.019) and FMDV (OR 5.68, 95% CI 1.58-20.3, p = 0.008), herds situated more than 30 km from an international border were more likely to be seropositive, while being located 10-30 km (OR 4.43, 95% CI 1.22-16.1 p = 0.024) from a border was identified as a risk factor for Brucella spp. For FMDV (OR 79.2, 95% CI 4.52-1388.9, p = 0.003), being situated within 30 km from a town was associated with seropositivity. Furthermore, contact with wild ruminants (OR 18.2, 95% CI 1.36-244), and the presence of sheep in the household (OR 5.20, 95% CI 1.00-26.9, p = 0.049), was associated with seropositivity for PPRV, and FMDV. No significant associa

Informal livestock markets are an important source of animal-derived proteins for growing urban populations in countries such as Zambia. In parallel, they can also constitute pathways of zoonotic pathogen transmission to humans. This risk is aggravated by limited disease monitoring and poor control systems with regards to biosecurity and public health. The aim of this study was to investigate the risks for spread of zoonotic diseases in Zambia's two largest informal small ruminant markets, located in Lusaka and Kasumbalesa, through combining seroepidemiology with interviews and observations. In April, May and September 2018, serum samples (n = 237) were collected and analysed for antibodies for the zoonotic pathogens Brucella spp., Coxiella (C.) burnetii and Rift Valley fever virus (RVFV), using commercially available enzyme linked immunosorbent assays (ELISA). In addition, slaughterhouse activities were observed and semi-structured interviews and focus group discussions held with slaughterhouse workers and small ruminant traders, focusing on the handling of animals and meat, and the perceptions of zoonotic disease risks at slaughter and consumption. The study found seropositivity rates of 10.1% (95% confidence interval [CI] 6.60–14.7) for Brucella spp., 5.9% (95% CI 3.27–9.71) for C. burnetii, and 0.8% (95% CI 0.10–3.01) for RVFV. Interviews with value chain members and observations at the slaughterhouse revealed unsanitary procedures and multiple occupational hazards for slaughterhouse workers. This study showed that the Zambian informal small ruminant trade system poses risks to public health, and that these risks are exacerbated by a lack of information about food-borne diseases and how associated risks can be mitigated amongst value chain actors. The results of this study can be used to formulate preventive measures to improve informal meat markets and reduce the risks to public health.

Bovine tuberculosis (bTB) is a neglected disease that affects cattle and humans. The burden of bTB is higher in developing countries as compared to industrialized countries. The reasons behind this discrepancy include the fact that bTB control measures, such as testing and slaughter of infected cattle and pasteurization of milk, are not usually practised in developing countries largely because of their high cost. To improve our understanding of bTB in developing countries, molecular typing studies are essential, in particular in terms of transmission dynamics, infection sources and knowledge of circulating strains of the principal causative agent, Mycobacterium bovis. In this study, we applied a suite of molecular typing techniques encompassing deletion analysis, spoligotyping and MIRU-VNTR to isolates recovered from samples collected during the routine post-mortem of cattle at the cold storage abattoir in Lilongwe, Malawi. Out of 63 isolates, 51 (81%) belonged to the European 1. M. bovis clonal complex. Spoligotyping identified 8 profiles, with SB0131 being the predominant type (56% of isolates). Spoligotypes SB0273 and SB0425 were identified in 14% and 13%, respectively, of the isolates. MIRU-VNTR showed a high discriminatory power of 0.959 and differentiated the 8 spoligotypes to 31 genotypes. The high diversity of M. bovis within the study area suggests the infection has been circulating in the area for a considerable period of time, likely facilitated by the lack of effective control measures. We also observed genetic similarities between isolates from Malawi (this study) to isolates described in previous studies in Zambia and Mozambique, suggesting transmission links in this region. The information provided by this study provides much needed evidence for the formulation of improved bTB control strategies.

Influenza A viruses (IAVs) cause highly contagious respiratory diseases in humans and animals. In 2009, a swine-origin pandemic H1N1 IAV, designated A(H1N1)pdm09 virus, spread worldwide, and has since frequently been introduced into pig populations. Since novel reassortant IAVs with pandemic potential may emerge in pigs, surveillance for IAV in pigs is therefore necessary not only for the pig industry but also for public health. However, epidemiological information on IAV infection of pigs in Africa remains sparse. In this study, we collected 246 serum and 605 nasal swab samples from pigs in Zambia during the years 2011-2018. Serological analyses revealed that 49% and 32% of the sera collected in 2011 were positive for hemagglutination-inhibition (HI) and neutralizing antibodies against A(H1N1)pdm09 virus, respectively, whereas less than 5.3% of sera collected during the following period (2012-2018) were positive in both serological tests. The positive rate and the neutralization titres to A(H1N1)pdm09 virus were higher than those to classical swine H1N1 and H1N2 IAVs. On the other hand, the positive rate for swine H3N2 IAV was very low in the pig population in Zambia in 2011-2018 (5.3% and 0% in HI and neutralization tests, respectively). From nasal swab samples, we isolated one H3N2 and eight H1N1 IAV strains with an isolation rate of 1.5%. Phylogenetic analyses of all eight gene segments revealed that the isolated IAVs were closely related to human IAV strains belonging to A(H1N1)pdm09 and seasonal H3N2 lineages. Our findings indicate that reverse zoonotic transmission from humans to pigs occurred during the study period in Zambia and highlight the need for continued surveillance to monitor the status of IAVs circulating in swine populations in Africa.

Influenza A viruses (IAVs) cause highly contagious respiratory diseases in humans and animals. In 2009, a swine-origin pandemic H1N1 IAV, designated A(H1N1)pdm09 virus, spread worldwide, and has since frequently been introduced into pig populations. Since novel reassortant IAVs with pandemic potential may emerge in pigs, surveillance for IAV in pigs is therefore necessary not only for the pig industry but also for public health. However, epidemiological information on IAV infection of pigs in Africa remains sparse. In this study, we collected 246 serum and 605 nasal swab samples from pigs in Zambia during the years 2011-2018. Serological analyses revealed that 49% and 32% of the sera collected in 2011 were positive for hemagglutination-inhibition (HI) and neutralizing antibodies against A(H1N1)pdm09 virus, respectively, whereas less than 5.3% of sera collected during the following period (2012-2018) were positive in both serological tests. The positive rate and the neutralization titres to A(H1N1)pdm09 virus were higher than those to classical swine H1N1 and H1N2 IAVs. On the other hand, the positive rate for swine H3N2 IAV was very low in the pig population in Zambia in 2011-2018 (5.3% and 0% in HI and neutralization tests, respectively). From nasal swab samples, we isolated one H3N2 and eight H1N1 IAV strains with an isolation rate of 1.5%. Phylogenetic analyses of all eight gene segments revealed that the isolated IAVs were closely related to human IAV strains belonging to A(H1N1)pdm09 and seasonal H3N2 lineages. Our findings indicate that reverse zoonotic transmission from humans to pigs occurred during the study period in Zambia and highlight the need for continued surveillance to monitor the status of IAVs circulating in swine populations in Africa.

Bluetongue (BT) is an arthropod-borne viral disease of ruminants with serious trade and socio-economic implications. Although the disease has been reported in a number of countries in sub-Saharan Africa, there is currently no information on circulating serotypes and disease distribution in Zambia. Following surveillance for BT in domestic and wild ruminants in Zambia, BT virus (BTV) nucleic acid and antibodies were detected in eight of the 10 provinces of the country. About 40% (87/215) of pooled blood samples from cattle and goats were positive for BTV nucleic acid, while one hartebeest pool (1/43) was positive among wildlife samples. Sequence analysis of segment 2 revealed presence of serotypes 3, 5, 7, 12 and 15, with five nucleotypes (B, E, F, G and J) being identified. Segment 10 phylogeny showed Zambian BTV sequences clustering with Western topotype strains from South Africa, intimating likely transboundary spread of BTV in Southern Africa. Interestingly, two Zambian viruses and one isolate from Israel formed a novel clade, which we designated as Western topotype 4. The high seroprevalence (96.2%) in cattle from Lusaka and Central provinces and co-circulation of multiple serotypes showed that BT is widespread, underscoring the need for prevention and control strategies.