Velogenic newcastle disease virus tissue tropism and pathogenesis of infection in chickens by application of in situ PCR, immunoperoxase staining and HE staining.

Limited deep studies are available in the field of early stages of pathogenesis of Newcastle disease virus (NDV) infection and tissue tropism of NDV. In this study, 24 specific pathogen free (SPF) chickens of white leghorn breed were infected with Newcastle disease (ND) by intranasal administration of 105 50% EID50/0.1 mL of velogenic NDV (vNDV). A second group of 15 chickens were kept as a control group. Chickens were monitored every day to record clinical signs. Infected chickens were euthanized by cervical dislocation at successive times, namely at hours (hrs) 2, 4, 6, 12, days 1, 2, 4, and 6 post-inoculation (pi). Whereas, control group chickens were euthanized on days 0, 1, 2, 4, and 6 pi. Tissues of brain, trachea, lung, caecal tonsil, liver, kidney, spleen, heart, proventriculus, intestine, and thymus were collected, fixed in 10% buffered formalin, embedded in paraffin, and sectioned. HS staining, immunoperoxidase staining (IPS) and in situ PCR were applied. It was concluded that at hr 2 pi, virus seemed to be inclined to trachea and respiratory tract. Meanwhile, it attacked caecal tonsils, intestine and bursa of Fabricus. While primary viraemia was ongoing, virus created footing in kidney and thymus. At hr 4 pi, proventriculus, liver, and spleen were attacked. However, at hr 6 pi, brain and heart were involved. Secondary viraemia probably started as early as hr 12 pi since all collected tissues were positive. Tissue tropism was determined in trachea, caecal tonsil, liver, bursa of Fabricius, intestine, proventriculus, lung, spleen, thymus, kidney, heart, and brain.

Tuberculosis in dromedary camels slaughtered in Nigeria: a documentation of lesions at postmortem.

In comparison with other livestock, tuberculosis (TB) in camels has not been extensively studied in Nigeria. Camels in the hands of Nigerian pastoralists share the livestock ecosystem and are increasingly becoming an important component of the sector. This study was designed to investigate the occurrence of TB lesions and animal-level risk of infection in slaughtered camel carcasses in one of the public abattoirs in Nigeria, from June to August 2016. A total of 212 camel carcasses comprising 82.5% (175/212) males and 17.5% (37/212) females were examined for tuberculous lesions. Of the carcasses examined, 33.5% (71/212) had TB lesions. The occurrence of lesions was most significantly associated with poor body condition (OR = 0.249; CI 0.134-0.454 [p < 0.001]). Distribution among anatomical sites of macroscopic lesions in the infected camels revealed three different pathological patterns as pulmonary (n = 51), abdominal (n = 11), and disseminated (n = 9) forms. Higher prevalence of gross TB lesions in camel carcasses highlights eminent threats to both animal and public health, pointing to an already existing risk of intra- and inter-species transmission of infection.

Appraisal of the knowledge, attitude, perception and practices among northern Nigerians in the wake of the COVID-19 outbreak.

Aim: The aim of this study was to measure the knowledge, attitude, perception and practices of northern Nigerians toward the COVID-19 pandemic. Materials & methods: This was a questionnaire-based cross-sectional study and the data were analyzed using descriptive and inferential statistics. Results & discussions: There were 713 participants, of which 54.0, 57.4, 67.6, 36.2 and 28.9% were between 18 and 30 years of age, married, males, having bachelor's degree and civil servants, respectively. High level of knowledge, attitude, perception and practice was found. Pearson correlation analysis found strong positive (r = 0.622; p < 0.001) relationships between knowledge, attitude, perception (r = 0.454; p < 0.001) and at last, practice (r = 0.282; p < 0.001). Conclusion: Young, male and married northern Nigerians of high socio-economic status had better knowledge, attitudes, perceptions and practices toward COVID-19.

Prevalence of fasciolosis (Liver flukes) infection in cattle in Zamfara, Nigeria: A slaughterhouse surveillance data utilizing postmortem examination.

Bovine fasciolosis, caused by Fasciola gigantica (F. gigantica) and rarely F. hepatica, is an economically important disease affecting cattle in tropical Africa. The aims of this study were to determine a year prevalence of bovine fasciolosis and correlate determinants of infection in slaughtered cattle at the municipal abattoir in Zamfara, Nigeria. Fasciola gigantica was detected in 15% (1740/11,562) cattle slaughtered during a daily postmortem examination (PME) between November 2016 and October 2017. This approach demonstrated an increase risk of liver fluke infection in older cattle (p = 0.001, AOR = 1.476, 95% CI: 1.188-1.832) and during rainfall (p = 0.003, AOR = 1.604, 95% CI: 1.176-2.187). Liver condemnation had been significantly found in hot-dry season (p ≤0.001, AOR = 0.518, 95% CI: 0.417-0.643) and adult cattle (p = 0.003, AOR = 1.726, 95% CI: 0.586-0.899). This study is an account of bovine fasciolosis prevalence and infection dynamics in part of the northwest region of Nigeria, which provides preliminary information for further studies to guide the design of appropriate control steps to lower the impact of the disease and safeguard public health.

Dressed chicken as potential vehicle for spread of methicillin-resistant Staphylococcus aureus in Sokoto, Nigeria.

AIM: To evaluate the role of dressed chicken in the spread of methicillin-resistant Staphylococcus aureus (MRSA) in Sokoto, Nigeria. MATERIALS & METHODS: 190 chicken carcass rinsates were subjected to culture and biochemical analyses to isolate and identify MRSA. PCR was used to amplify mecA gene that is responsible for methicillin resistance. RESULTS & CONCLUSION: Culture and molecular analysis showed 19.5% (37/190) of the rinse had MRSA on oxacillin-resistance screening agar base (ORSAB) with 7.9% (15/190) possessing the mecA gene. Significant association (p = 0.044) exist between local-chicken and presence of MRSA, being twice more likely to have MRSA compared to exotic-chickens (odds ratio [OR] = 2.132). Results indicate possible role of dressed-chicken in the spread of MRSA. Authorities should regulate the sale and use of antibiotics by farmers, and enhance hygienic practices at slaughterhouses.

Disseminated tuberculosis in a cow and a dromedary bull-camel in Zamfara State in Nigeria.

In 2017, cases of generalized tuberculosis (TB) were identified in a cow and a bull-camel, slaughtered at the Gusau abattoir in Zamfara State Nigeria. The objective of this study was to identify the cause of the gross pathology on the account of disseminated lesions widely distributed in different body parts of the animals. Tissue samples were analysed using Ziehl-Neelsen (ZN) stain and region of difference (RD) deletion typing. Results obtained by laboratory investigations revealed infection with acid-fast tubercle bacilli in affected tissues from the cow and the dromedary bull-camel. This study presents the first molecular evidence of Mycobacterium bovis infection in a Nigerian dromedary camel, demonstrated the ease of identification of the acid-fast bacilli using molecular method which improves diagnosis and can aid epidemiological studies.

Risk of Shiga Toxigenic Escherichia coli O157:H7 Infection from Raw and Fermented Milk in Sokoto Metropolis, Nigeria.

Escherichia coli O157:H7 is an enteric foodborne pathogen associated with life threatening disease conditions. The enterobacteria are frequently found in cattle gastrointestinal tract with high potential of contaminating animal products such as meat, milk, and cheese. A cross-sectional study was conducted to investigate the presence of Shiga toxin-producing Escherichia coli O157:H7 in milk products sold within Sokoto metropolis. Two hundred and sixty (260) samples (comprising 160 raw and 100 fermented milk samples) were collected from different sources within the study area. Bacteriological isolation and biochemical characterization yielded Escherichia coli with a detection rate of 9.23% (24/260). Molecular identification of the recovered isolates by PCR amplification of the Stx1 gene revealed Escherichia coli O157:H7 with a positive rate of 20.83% (5/24). The overall prevalence of E. coli O157:H7 was 1.92% (5/260) and the positive proportions for raw and fermented milk samples were 1.86% (3/160) and 2.0% (2/100), respectively. Fisher's Exact test showed a nonsignificant association between the isolates and the different milk types (p = 0.943; OR = 0.94; [95% CI: 0.154-5.704]). The results revealed presence of Escherichia coli O157:H7 in raw and fermented milk sold within Sokoto metropolis, Nigeria. The findings indicate possible feacal contamination of the milk products, with serious public health consequences. This necessitates the need to screen other milk products produced in the area such as butter and cheese. Health authorities in the State need to enlighten dairy farmers on the zoonotic potential of Escherichia coli O157:H7 and the role of cattle in the spread of the pathogen.

Evidence and potential risk factors of tuberculosis among captive Asian elephants and wildlife staff in Peninsular Malaysia.

Elephant tuberculosis (TB) caused by Mycobacterium tuberculosis is an important re-emerging zoonosis with considerable conservation and public health risk. We conducted prospective cohort and cross-sectional studies in elephants and wildlife staff respectively in order to identify potential risk factors associated with TB in captive Asian elephants and their handlers in Peninsular Malaysia. Sixty elephants in six different facilities were screened for TB longitudinally using the ElephantTB STAT-PAK and DPP VetTB assays from February 2012 to May 2014, and 149 wildlife staff were examined for tuberculosis infection using the QuantiFERON-TB Gold In-tube (QFT) assay from January to April, 2012. Information on potential risk factors associated with infection in both elephants and staff were collected using questionnaires and facility records. The overall seroprevalence of TB amongst the elephants was 23.3% (95% CI: 13.8-36.3) and the risk of seroconversion was significantly higher among elephants with assigned mahouts [p=0.022, OR=4.9 (95% CI: 1.3-18.2)]. The percentage of QFT responders among wildlife staff was 24.8% (95% CI: 18.3-32.7) and the risk of infection was observed to be significantly associated with being a zoo employee [p=0.018, OR=2.7 (95% CI: 1.2-6.3)] or elephant handler [p=0.035, OR=4.1 (95% CI: 1.1-15.5)]. These findings revealed a potential risk of TB infection in captive elephants and handlers in Malaysia, and emphasize the need for TB screening of newly acquired elephants, isolating sero-positive elephants and performing further diagnostic tests to determine their infection status, and screening elephant handlers for TB, pre- and post-employment.