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The rise in the spread of antibiotic-resistant pathogens such as Escherichia coli is one of the very important dynamics off-putting treatment and prophylaxis possibilities, hence posing a threat to the modern human medicine, veterinary medicine, and food safety. Therefore, the aim of this study was to determine antimicrobial resistance profiles in E. coli isolates obtained from broiler and layer chickens in Mwanza and Arusha regions in Tanzania. A cross-sectional study was carried out from February to March, 2021, in 402 poultry farms in Mwanza (201) and Arusha (201) regions in Tanzania. All samples that tested positive for E. coli were confirmed using MALDI-TOF MS, and two hundred and four (204) E. coli isolates were randomly chosen and subjected to antimicrobial susceptibility testing by disc diffusion method. Data were entered in Microsoft Excel® and analyzed using SPSS version 20. Isolates were tested against seven antimicrobial agents belonging to seven classes of antimicrobials. All the tested isolates (n = 204) were resistant to at least one antimicrobial agent. Overall, the highest resistance was observed in ampicillin (100%), whereas the lowest resistance was recorded for gentamicin (10.3%). Majority of the isolates (86.76%) were multidrug resistant. Antimicrobial resistance of E. coli to four classes of antimicrobial agents was the highest in this study (31.1%). Six of the 177 tested isolates (2.9%) were resistant to the seven classes of antimicrobial agents. 21 of the 204 (10.29%) isolates were ESBL producers where 21/21 (100%) isolates expressed blaTEM genes and only two isolates expressed (2/21) blaCTX-M gene. The isolates obtained in this study displayed high resistance to commonly used antimicrobial agents in veterinary and human medicine. This implies that there is existence of practices that accelerate antimicrobial resistance in the production of the sampled birds and therefore integration of appropriate use of antimicrobial agents and other measures that curb the spread of resistant genes is necessary.

Chickens in live bird markets (LBMs) from six different regions of Tanzania were surveyed for Newcastle disease (ND) virus (NDV) and avian influenza virus in 2012. ELISA-based serology, virus isolation, and characterization, including pathotyping was conducted. Virulent NDV was isolated from almost 10% of the tested samples, with two distinct genotypes being detected. One genotype was similar to recent viruses circulating in Kenya and Uganda, which share a northern border with Tanzania. Several viruses of this genotype were also isolated from Tanzania in 1995, the last time surveillance for NDV was conducted in the country. The second genotype of virus from Tanzania was closely related to viruses from Mozambique, a southern neighbor, and more distantly to viruses from South Africa, Botswana, and several European countries. Partial fusion gene sequence from the isolated viruses showed identical fusion cleavage sites that were compatible with virulent viruses. Selected viruses were tested by the intracerebral pathogenicity index, and all viruses tested had scores of1.78, indicating highly virulent viruses. Serology showed only a third of the chickens had detectable antibody to NDV, suggesting that vaccination is not being commonly used in the country, despite the availability of vaccines in agricultural-related markets. All samples were taken from clinically healthy birds, and it is believed that the birds were sold or slaughtered before showing ND clinical signs. LBMs remain a biosecurity risk for farmers through the return of live infected birds to the farm or village or the movement of virus on fomites, such as uncleaned wooden cages.Aislamiento y caracterización de virus de la enfermedad de Newcastle de mercados de aves vivas en Tanzania. Se llevó a cabo un muestreo de pollos en mercados de aves vivas (LBM) de seis regiones diferentes de Tanzania para detectar al virus de la enfermedad de Newcastle (NDV) y el virus de la influenza aviar en el año 2012. Se llevaron a cabo la serología basada en la prueba de ELISA, el aislamiento viral y la caracterización, incluyendo la determinación del patotipo. Formas virulentas del virus de Newcastle se aislaron de casi el 10% de las muestras analizadas y se detectaron dos genotipos distintos. Un genotipo era similar a los virus recientes que circulan en Kenia y Uganda, países que comparten una frontera al norte de Tanzania. Varios virus de este genotipo también se aislaron de Tanzania en el año 1995, la última vez que se realizó la vigilancia del virus de Newcastle en el país. El segundo genotipo de virus de Tanzania estaba estrechamente relacionado con virus de Mozambique, país vecino al sur, y más distantemente con virus de Sudáfrica, Botswana y de varios países europeos. Una secuencia parcial del gene de fusión de los virus aislados mostró sitios de disociación en la proteína de fusión idénticos que eran compatibles con los virus virulentos. Los virus seleccionados fueron analizados mediante el índice de patogenicidad intracerebral y todos los virus analizados tuvieron puntajes mayores de 1.78, lo que indica que son virus altamente virulentos. La serología mostró que solo un tercio de los pollos tenían anticuerpos detectables contra el virus de Newcastle, lo que sugiere que la vacunación no se usa comúnmente en el país, a pesar de la disponibilidad de vacunas en los mercados agrícolas. Todas las muestras fueron recolectadas de aves clínicamente sanas y se cree que las aves fueron vendidas o sacrificadas antes de mostrar signos clínicos de la enfermedad de Newcastle. Los mercados de aves vivas siguen siendo un riesgo de bioseguridad para los agricultores mediante el regreso de aves vivas infectadas a la granja o a los pueblos o por el movimiento de virus en fómites, como las jaulas de madera sin limpiar.

The genus Campylobacter comprises members known to be a leading cause of foodborne gastrointestinal illness worldwide. A study was conducted to determine the epidemiology and antimicrobial resistance of Campylobacter in humans in Morogoro, Eastern Tanzania. Isolation of Campylobacter from stool specimens adopted the Cape Town protocol. Campylobacter isolates were preliminarily identified by conventional phenotypic tests and subsequently confirmed by matrix-assisted laser desorption/ionization-time-of-flight (MALDI-TOF) mass spectrometry and polymerase chain reaction. Antimicrobial resistance testing employed the disc diffusion method. A small proportion of the test isolates was also subjected to agar dilution method. Risk factors for human illness were determined in an unmatched case-control study. Thermophilic Campylobacter were isolated from 11.4% of the screened individuals (n = 1195). The agreement between PCR and MALDI-TOF was perfect (κ = 1.0). Symptomatics and young individuals were infected with higher numbers than asymptomatic and adults, respectively. The majority (84.6%) of the isolates were C. jejuni and the remaining were C. coli. Isolates had highest resistance (95.6%) for colistin sulphate and lowest for ciprofloxacin (22.1%). The rates of resistance for other antibiotics (azithromycin, erythromycin, tetracycline, cephalothin, gentamycin, nalidixic acid, ampicillin, amoxycillin, norfloxacin, chloramphenicol) ranged from 44.1% to 89%. Comparison between disc diffusion and agar dilution methods indicated a good correlation, and the tests were in agreement to each other (κ ≥ 0.75). Human illness was found to be associated with young age and consumption of chicken meat and pre-prepared salad. Our data indicate the presence of antibiotic-resistant thermophilic Campylobacter in humans in the study area. There is a need for routine investigation of the presence of the organisms in gastroenteritis aetiology, including determination of their antibiotic susceptibilities.

Urban and peri-urban livestock farming is expanding world-widely because of increased urbanization and demands for food of animal origin. Such farming practices pose a public health risk as livestock are reservoirs of several zoonotic pathogens. In an attempt to determine the fecal transmission between livestock and people, 100 household clusters keeping cattle in close proximity of humans were selected in urban and peri-urban areas of Morogoro in Tanzania. One hundred eighteen ampicillin and tetracycline resistant Escherichia coli (40 from human stool, 50 from cattle feces, 21 from soil and seven from water samples) were isolated from 44 different clusters. Pulsed-field gel electrophoresis (PFGE) of XbaI digested chromosomal DNA was used to compare the genetic relatedness of the ampicillin- and tetracycline-resistant E . coli isolates. Indistinguishable PFGE band patterns of the ampicillin- and tetracycline-resistant E. coli isolates were found in samples from 23 (52%) clusters. This suggests that transfer of fecal microorganisms between cattle, humans, water and soils within the farms and from livestock farms to the neighborhood occurred commonly. Logistic regression showed that animal housing infrastructures (Odd Ratio = 11.2, 95% CI = 1.1–119.3) were associated with E . coli showing identical PFGE types within and between clusters. There is a need to improve animal husbandry and manure management practices to reduce risks of transmission of enteropathogens between livestock and humans in urban and peri-urban farming.

Aim: To determine the carriage and antimicrobial resistance of Thermophilic Campylobacter species in the gastrointestinal tracts of farm and laboratory animals in Morogoro, Tanzania Materials and Methods: Faecal samples were collected from farm (n=244) and laboratory (n=466) animals and were subjected to the Cape Town protocol for isolation of Campylobacter. Isolates were preliminarily identified based on potassium hydroxide string and hippurate hydrolysis tests. Polymerase chain reaction (PCR) was employed for confirmation of isolates. Antimicrobial resistance testing was done using disc diffusion method. Results: Of the laboratory animals 26.7% of guinea pigs (n=30) and 1.2% of rats (n=242) were colonized with Campylobacter. Four isolates from guinea pigs were Campylobacter jejuni and the other four were C. coli. From rats, two isolates were C. jejuni and one was C. coli. In farm animals thermophilic Campylobacter were detected from 31.6% of sheep (n=57) and 60% horses (n=5). Of the isolates 12 (57%) were C. jejuni (10 from sheep and 2 from horses) and the remaining were C. coli (8 from sheep and 1 from a horse). The isolates were frequently resistant to erythromycin, norfloxacin, colistin sulphate and nalidixic acid; whereas low levels of resistance were observed for ciprofloxacin and gentamicin. Conclusion: Our study reveals carriage of antimicrobial resistant thermophilic Campylobacter in the intestines of the study animals. This highlights possibilities in involvement of these animals in the epidemiology of Campylobacter infections. Thus, there is a need to consider these animal species when planning control measures for this zoonotic bacterium.

The perception of risks of exposure to avian influenza and other poultry diseases among adults in Tanzania is influenced by their previous experiences, beliefs, and values, which can stand in the way of learning new approaches. We tested a novel disease risk communication approach centered on elementary school pupils, involving their teachers and parents. Age-appropriate training modules were developed and taught to teachers who then taught their pupils through extracurricular activities. The pupils practiced what they learned through club projects and subsequently transmitted what they learned to their parents. In 2009 we developed a poultry health and production curriculum as part of efforts to prevent and control poultry diseases, including avian influenza, in Tanzania. The curriculum developed for veterinarians and veterinary paraprofessionals was adapted for use with elementary school children and translated into Kiswahili. Twenty teachers from 10 primary schools in Mzumbe ward, Morogoro, were trained by poultry veterinary extension experts on teaching the curriculum to standard 5 pupils (ages 11-12 yr). Pupils and teachers practiced the curriculum in four demonstration chicken coops established on the grounds of the Changarawe, Lubungo, Masanze, and Mzumbe primary schools. By October 2011, at the conclusion of the funded project, a total of 202 girls and 193 boys had been trained. Additionally, 34 adults from surrounding villages made official learning tours to the schools and received training from their children and teachers involved in the projects. With at least 75% of the 395 pupils coming from different households, it can be safely assumed that over 250 households have heard about poultry disease risks and how to manage poultry to prevent those risks.

A study was conducted to evaluate the disease resistance potential in 105 chickens of six indigenous local chicken ecotypes in Tanzania by orally challenging 1-week-old chicks with 2.5 x 10(8) colony-forming units of virulent S. Gallinarum. For 14 days post infection, clinical signs, necropsy findings, antibody titres, packed cell volume, leukocyte population count, and viable bacterial cell counts in the liver and spleen were recorded. Clinical signs were recorded daily but other parameters were recorded on the day of infection, then on days 3, 6, 10 and 14 after infection. Clinical signs of fowl typhoid were evident in chickens from day 3 post infection and disappeared by day 9 post infection. Pathological lesions on sacrificed birds included enlargement of the liver and spleen with foci of necrosis on the liver, spleen and myocardium. The mean viable bacterial cell counts in the liver and spleen varied between ecotypes, although the differences were not statistically significant. There were significant differences in the leukocyte population in the peripheral blood, with one ecotype (Morogoro-medium) showing a consistent and significantly higher heterophil count compared with other ecotypes. It was concluded that there is a selectable resistance potential to S. Gallinarum among the local chicken ecotypes in Tanzania that may be attributable to non-specific host immune responses. Further studies are suggested.

The pathogenicity of a virulent strain of Salmonella gallinarum was studied in local chickens and commercial layers. Sixty 4-month-old chickens were used. Of these, 50 chickens were orally infected with S. gallinarum, comprising 25 commercial layers and 25 local chickens. Five chickens in each group were used as uninfected negative controls. The clinical signs and pathological features of acute, subacute and chronic fowl typhoid were observed in both groups. Chickens in both groups seroconverted, but the antibody titre was significantly higher (p

Escherichia coli strains such as Shiga toxin-producing E. coli (STEC), enteropathogenic E. coli, enterotoxigenic, attaching, and effacing E. coli, and enteroinvasive E. coli cause diarrhea in humans. Although other serotypes exist, the most commonly reported STEC in outbreaks is O157:H7. A cross-sectional study was conducted to isolate and characterize non-sorbitol-fermenting (NSF) E. coli O157:H7 from urban and periurban livestock settings of Morogoro, Tanzania. Human stool, cattle feces, and soil and water samples were collected. Observations and questionnaire interview studies were used to gather information about cattle and manure management practices in the study area. E. coli were isolated on sorbitol MacConkey agar and characterized by conventional biochemical tests. Out of 1049 samples, 143 (13.7%) yielded NSF E. coli. Serological and antimicrobial tests and molecular typing were performed to NSF E. coli isolates. These procedures detected 10 (7%) pathogenic E. coli including STEC (n=7), enteropathogenic E. coli (EPEC) (n=2), and attaching and effacing E. coli (A/EEC) (n=1) strains. The STEC strains had the ability to produce VT1 and different VT2 toxin subtypes that caused cytopathic effects on Vero cells. The prevalence of STEC in cattle was 1.6%, out of which 0.9% was serotype O157:H7 and the overall prevalence of diarrheagenic E. coli in cattle was 2.2%. The serotypes O157:H7, O142:H34, O113:H21, O+:H-, O+:H16, and O25:H4 were identified. One ESBL-producing isolate showed the MLST type ST131. To our knowledge, this is the first finding in Tanzania of this recently emerged worldwide pandemic clonal group, causing widespread antimicrobial-resistant infections, and adds knowledge of the geographical distribution of ST131. Cattle manure was indiscriminately deposited within residential areas, and there was direct contact between humans and cattle feces during manure handling. Cattle and manure management practices expose humans, animals, and the environment to pathogenic E. coli and other manure-borne pathogens. Therefore, there is a need to improve manure management practices in urban and periurban areas to prevent pathogen spread and associated human health risks.

The implementation of strategies to detect, prevent, and control highly pathogenic avian influenza (HPAI) in developing countries presents several challenges, one of which is the presence of other diseases in poultry populations. Training workshops in developing countries using the Avian Flu School have revealed that in areas with heavy Newcastle disease burdens, smallholder poultry keepers do not recognize HPAI as an immediate threat. We have developed a strategy to address the more proximal needs and priorities of communities with free-ranging poultry flocks as a means to create value in poultry, and thus to improve disease detection and prevention overall. To this end, we have created the Poultry Health and Well-Being for Development project, which trains graduate veterinarians and paraprofessionals in poultry disease diagnosis, control, and treatment. These trainees then serve their local communities to improve poultry health and to implement disease detection and management programs.

A study was carried out to confirm and identify sources and elucidate factors associated with the introduction of Peste des Petits Ruminants (PPR) in southern Tanzania. This study was conducted in Tandahimba and Newala districts of Mtwara region following suspected outbreak of PPR in the area. Qualitative data were collected using semi-structured questionnaires and in-depth interviews of key informants who included goat and sheep owners with suspected cases of PPR and animal health service providers as well as local administrative authority. Additionally, 216 serum samples and 28 swabs were collected for serological and virological laboratory disease confirmation. The results show that PPR was first introduced in Likuna village of Newala district in February 2009 through newly purchased goats from the Pugu livestock market located about 700 km in the outskirts of Dar es Salaam city. Factors which contributed to spread of PPR included communal grazing and the cheap prices of sick animals bought by livestock keepers for slaughtering in other villages. Laboratory findings confirmed presence of PPR in the area by RT-PCR and serological analysis revealed that seroprevalence was 31%. These findings have confirmed, for the first time, introduction of PPR in southern Tanzania. The presence of PPR poses high risk of southward spread of the disease to other southern African countries in the SADC region thus calling for concerted and collaborative efforts in prevention and control of the disease to avoid losses. Further elaborate studies on the spread, prevalence and risk factors associated with the disease should urgently be investigated.

Free-ranging local chicken flocks are important for the livelihood of resource-poor rural farmers in Tanzania, as they provide a critical source of animal protein and a ready source of income through the sale of chickens and eggs. An occurrence of highly pathogenic avian influenza (HPAI) in the village setting of Tanzania would result in a disastrous loss of livelihood. This paper attempts to offer an alternative method for preventing and controlling HPAI in village settings of Tanzania through community-based approaches.

A social strategy was tested for implementing Newcastle disease (ND) vaccination and biosecurity improvements among free-ranging chicken at village level in Tanzania. In addition to training the local poultry vaccinators, data recorders and poultry-keepers, the strategy involved training and empowering leaders at the district, ward and village level. The trainings covered poultry health, management, and marketing of village chickens, with an emphasis on ND vaccination and improving biosecurity against avian influenza (AI), The study sites included villages in one ward in each of three each three districts (Iringa, Mtwara-Mikindani, and Mvomero) of mainland Tanzania. Ninety-six local leaders at district level and 101 leaders at ward levels were trained. In addition, 196 farmers (households) were trained, as well as 86 vaccinators and 26 data recorders. Data recorders were also trained as poultry first aid workers. ND vaccination was conducted by the vaccinators, supervised by their local leaders with technical assistance from veterinarians. A total of 158,343 village chickens were vaccinated in three rounds of vaccination three months apart. The training and empowerment of local leaders and local implementers was the key element for success as it fostered the feeling of local ownership of the program and prevented conflicts with other development activities within the villages. We conclude that most animal health programs will increase their odds of success by involving local leaders and by addressing the current challenges facing the farmers. Further assessment on the usefulness of this approach is needed.