Status of trace metals and arsenic in sediments and catfish muscles (Clarias gariepinus) from the Eastern Tanzanian basin.

Trace metals and metalloids are groups of chemical elements that naturally occur in low concentrations and cycle in the environment driven by natural processes and human activities. They have a persistent and bio-accumulative tendency in the environment, and certain trace metals and metalloids have become a public health concern. This study assesses the concentration of eleven trace metals and a metalloid in sediments and catfish muscle from five study sites in the Eastern Tanzanian River basin. Forty catfish tissues and fifteen sediment samples were collected and analyzed using ICP-MS. Concentrations of As, Cd, Co, Pb, and Zn did not exceed the United States Environmental Protection Agency (USEPA) guideline for pollution of sediments, while Al Cr, Al, Mn, and V with values ranging from (118.54 to 70154.55) indicating moderately polluted. The stations Java-Sadaani and Matandu showed the highest Cr, Ni, and Cu concentrations, but the potential ecological risk index (RI) was low (RI < 95). In the catfish muscle tissue, the levels of Cd, Pb, Cu, and Zn did not surpass the EU and FAO/WHO limits and results ranged from 2.22 to 35.22mg/kg. Low levels of accumulation of Cd, Pb, and As were found in this study compared to catfish muscles from other studies, whereas the concentrations of other trace metals and metalloids analyzed had comparable results. Biota/sediment accumulation factors (BSAF) were all < 1. The weekly metal intake (MWI) results ranged from 6.89E-04 to 2.43E+01 µg/know-1week-1, indicating a low risk as the value did not exceed the FAO/WHO established Permissible Tolerable Weekly Intake (PTWI). The non-carcinogenic health risk result THQ was 4.43E-02 and the carcinogenic health risks result HI was 4.42E-05 which indicated tolerable levels of risks as both the values of the Target Hazard Quotient (THQ) and the Hazard Index (HI) was < 1, and the carcinogenic target risk (TR) is < 0.0001. The highest TR values were observed for Cr and Ni. We recommend a continued monitoring of the changes in trace metal levels in the environment and biota together with continuous public health education on the dangers of high levels of trace metals.

Existence of variant strains Fowlpox virus integrated with Reticuloendotheliosis virus in its genome in field isolates in Tanzania.

Fowlpox virus (FPV) is one example of poultry viruses which undergoes recombination with Reticuloendotheliosis virus (REV). Trepidation had been raised, and it was well established on augmented pathogenicity of the FPV upon integration of the full intact REV. In this study, we therefore intended at assessing the integration of REV into FPV genome of the field isolates obtained in samples collected from different regions of Tanzania. DNA extraction of 85 samples (scabs) was performed, and FPV-specific PCR was done by the amplification of the highly conserved P4b gene. Evaluation of FPV-REV recombination was done to FPV-specific PCR positively identified samples by amplifying the env gene and REV long terminal repeats (5' LTR). A 578-bp PCR product was amplified from 43 samples. We are reporting for the first time in Tanzania the existence of variant stains of FPV integrated with REV in its genome as 65 % of FPV identified isolates were having full intact REV integration, 21 % had partial FPV-REV env gene integration and 5 % had partial 5' LTR integration. Despite of the fact that FPV-REV integrated stains prevailed, FPV-REV-free isolates (9 %) also existed. In view of the fact that full intact REV integration is connected with increased pathogenicity of FPV, its existence in the FPV genome of most field isolates could have played a role in increased endemic, sporadic and recurring outbreaks in selected areas in Tanzania.

Sanitary practices and occurrence of zoonotic conditions in cattle at slaughter in Morogoro Municipality, Tanzania: implications for public health.

As meat consumption is increasing worldwide to cover for protein demands, also raise concerns and challenges regarding meat hygiene and safety. The current one year follow up study aimed at investigating on sanitary practices and occurrence of zoonotic conditions, during post-mortem examination, in cattle at slaughter in Morogoro Municipality abattoir. Sanitary practices were assessed through direct observation where as routine post-mortem inspection procedures were employed to detect zoonotic conditions in cattle at slaughter. During the study period a total of 30,713 cattle were slaughtered and inspected at the abattoir. Results revealed poor hygienic practices at the level of abattoir surrounding, the slaughter operation area, personnel as well as meat vans. Whole carcasses, lungs, livers, hearts and heads were condemned due to zoonotic conditions at rates of 0.026%, 1.96%, 1.61%, 0.02% and 0.21% respectively. Bovine tuberculosis, Cysticercus bovis cysts, fasciolosis and hydatidosis were the responsible zoonotic conditions for the condemnations. Bovine tuberculosis was a leading zoonotic cause of condemnations accounting for 95.7% of lungs and 100% of all head and carcass condemnations. Cysticercus bovis cysts were ranking the second in serving as causes of condemnations closely followed by fasciolosis and lastly hydatidosis. Occurrence of disease conditions with zoonotic implication in cattle at slaughter, meant for human consumption, may pose significant economic and public health risks to especially disaster-prone marginalized communities. Thus, there is a need to introduce appropriate control measures of livestock diseases to minimize the rate of infection; and eventually reduce economic losses and safeguard public health.