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Abstract Background Lumpy Skin Disease (LSD) is endemic in sub-Saharan countries and is currently a global threat to the cattle industry. Information on the circulating Capripoxvirus lumpyskinpox, formerly known as Lumpy Skin Disease Virus (LSDV), and other poxviruses infecting cattle is very scant in Tanzania. The current study aimed to confirm and characterize LSDV and other poxviruses infecting cattle, from LSD suspected outbreaks in Tanzania. Methods A total of 24 samples were collected from four LSD suspected outbreaks reported in Tanzania between February and May 2023. Samples were screened for LSDV genome by real-time PCR and then subjected to a high-resolution multiplex melting (HRM) assay where 10 samples were positive for Capripoxvirus (CaPV) and one sample was Parapoxvirus (PPV) positive. Four LSDV genes; RPO30, GPCR, EEV glycoprotein and B22R and the partial B2L gene of PPVs were analyzed. Results All targeted LSDV genes from the Tanzanian isolates showed 100% similarity and isolates clustered with commonly circulating LSDV field isolates. Furthermore, the single nucleotide polymorphism (SNP) at position 240 (A-> G) of the EEV gene differentiates the Tanzanian LSDVs from the group of ancient Kenyan LSDV isolates while the B22R sequences of the Tanzanian LSDV isolates differed from the LSDV Neethling and LSDV KSGP-0240 derived vaccines. Sequence analysis of the partial B2L gene of the Tanzanian parapoxvirus bovinestomatitis, formerly known as Bovine papular stomatitis virus (BPSV) showed a different BPSV strain circulating compared to publicly available sequences. Conclusion These findings confirm the presence of LSDV in Tanzania, which suggesting the need for establishing an effective control program and continuous monitoring. The presence of a typical profile for Tanzania BPSV is an indication that, although never reported before, BPSV is established in the country therefore this virus should be included in the differential diagnosis of LSDV.

Lumpy skin disease (LSD) is an infectious disease of cattle caused by lumpy skin disease virus (LSDV), which is a member of the Poxviridae family and genus Capripoxvirus. The illness is marked by mild to severe symptoms, including edema, fever, lymphadenitis, widespread skin nodules, and infrequently, death. In spite of its significance, little is now understood about the magnitude and predisposing factors in Tanzania. The aim of this study was to determine the seroprevalence of LSD in cattle within Kilolo district, and to identify key predisposing factors. A cross-sectional study was conducted in 17 villages within Kilolo district from February to March 2024 to estimate the seroprevalence of LSD in cattle. A total number of 276 serum samples was obtained from 65 cattle herds and a Double Antigen ELISA (ID Screen®) (IDVet, France) was used to screen for LSDV antibodies. Logistic regression analysis was employed to assess the risk factors for LSD seropositivity. The overall animal- and herd-level seroprevalence were 18.1% (95% CI: 13.98–23.14) and 44.6% (95% CI: 7.54–15.38), respectively. The highest individual animal level seroprevalence was documented in Irindi village 39.1% (95% CI: 5.36–12.24), followed by Masalali 38.5% (95% CI: 6.25–13.50), Ng’uruhe 37.5% (95% CI: 5.65–12.66), Irole 33% (95% CI: 1.5–6.10), and Utengule 26.5% (95% CI: 3.07-8.81) with significant differences (p=0.003). The seroprevalence of LSD varied significantly (P2 years having a higher seroprevalence (29.8%, 95%CI, 52.27–64.21) than yearlings aged 1-2 years (5. 6%, 95%CI, 9.31–17.60) and calves (0.0%, 95%CI, 23.36-34.35). Sex (Female/male, OR=2.0937, 95%CI, 1.4642-3.0248), age (Yearling/Adult, OR=0.1756, 95%CI, 0.0841-0.3730), village (OR=0.8970, 95%CI, 0.8349-0.9636) and herd size (Large/small, OR=1.9464, 95%CI, 1.1597-3.2669) were significant risk factors for LSDV seropositivity in Kilolo district. Raising awareness among livestock owners and veterinary staff about the disease and its risk factors, vaccination and vector control measures should be prioritized to minimize the transmission of the disease.

Abstract Background Cholera outbreaks are a recurrent issue in Tanzania, with Ilemela and Nkasi districts being particulary affected. The objective of this study was to conduct a socio-ecological system (SES) analysis of cholera outbreaks in these districts, identifying potential factors and assessing the preparedness for cholera prevention and control. Methods A cross-sectional study was carried out in Ilemela and Nkasi districts of Mwanza and Rukwa regions, respectively in Tanzania between September and October 2021. A SES framework analysis was applied to identify potential factors associated with cholera outbreaks and assess the readiness of the districts to cholera prevention and control. Results Ilemela is characterised by urban and peri-urban ecosystems while Nkasi is mainly rural. Cholera was reported to disproportionately affect people living along the shores of Lake Victoria in Ilemela and Lake Tanganyika in Nkasi, particularly fishermen and women involved infish trading. The main potential factors identified for cholera outbreaks included defecation in the shallow ends and along the edges of lakes, open defecation, bathing/swimming in contaminated waters and improper waste disposal. The preparedness of both districts for cholera prevention and response was found to be inadequate due to limited laboratory capacity, insufficient human resources, and budget constraints. Conclusion People of Ilemela and Nkasi districts remain at significant risk of recurrent cholera outbreaks and the capacity of the districts to detect the disease is limited. Urgent preventive measures, such as conducting considerable community awareness campaigns on personal hygiene and environmental sanitation are needed to alleviate the disease burden and reduce future cholera outbreaks.

Background: One of the most significant and perilous challenges faced by African societies, including Tanzania, is the public health threat posed by zoonotic viruses. This study aimed to ascertain the presence of viruses in wild rodents, domestic dogs, and humans who shared the same environment. Methods: A cross-sectional study was conducted in the Ngorongoro district from January to September 2022. Metagenomics next-generation sequencing technologies, including Illumina (MiSeq) and Oxford Nanopore (MinION), were employed to identify viruses in 530 blood samples collected from 200 humans, 230 wild rodents, and 100 domestic dogs. The captured wild rodents belonged to various species: Mastomys spp (n=87), Ratus spp (n=45), Avicanthis spp (n=40), Arcomys spp (n=28), Mus spp (n=16), and Field mice (n=14). The taxonomic classification of viruses was carried out using the Kraken2 program. Results: A total of 20 RNA and 20 DNA viral families were detected. Zoonotic RNA families identified in rodents included Peribunyaviridae, Hantaviridae, Flaviviridae, Coronaviridae, Orthomyxoviridae, Paramyxoviridae, Retroviridae, Picornaviridae, Arenaviridae, Togaviridae, and Tobaniviridae. The zoonotic DNA families detected in rodents were Adenoviridae, Poxviridae, Herpesviridae, Anelloviridae, and Circoviridae. Peribunyaviridae and Hataviridae were identified in both humans and rodents. Unclassified +ssRNA viruses were found in dogs and humans. Herpesviridae was present in all three hosts. When compared to dogs and humans, rodents harbored zoonotic viruses that pose a significant public health safety concern. Conclusion: The study unveiled a noteworthy pattern where the majority of RNA and DNA viruses with zoonotic potential were detected in wild rodents, as opposed to dogs and humans. These findings underscore the pivotal role played by wild rodent populations in the transmission and maintenance of such viruses.

In addition to their economic significance, rodents are hosts and transmit diseases. Most of rodent-borne diseases are endemic in rural Africa and sporadically lead to epidemics. Ngorongoro district is inhabited by humans, livestock, and wild animals. Therefore, a cross-sectional study was conducted to assess the level of knowledge, attitudes, and practices toward rodent-borne diseases among communities. The study used 3 focus groups, 20 key informant interviews, and the questionnaire (N=352) to collect data. The study found that 8.52% of respondents had good knowledge, 35.5% had a positive attitude and 94.3% had good practices toward rodent-borne diseases. The study revealed that only 28.13% of participants were aware of rodent-borne zoonoses. The majority of them (77.27%) believe that rodents are pests that destroy crops and do not transmit pathogens. Moreover, the results showed that the majority of them (82.9%) live in dilapidated huts that serve as rodent breeding places. Additionally, except for education and religion, the level of knowledge had no significant relationship with most of the participants’ demographic variables. When compared to individuals who didn’t attend school, those with secondary education (OR=7.96, CI=1.4-45.31, P=0.017) had greater knowledge of rodent-borne diseases and management. Similarly, to how attitude and practice were found to be considerably (r=0.3216, P=0.000) positively correlated, general knowledge and general practice scores were found to be significantly (r=0.1608, P=0.002) positively correlated. Despite showing good practices, the communities still lack knowledge of rodent-borne zoonosis. Rodent-borne disease education should be considered in Ngorongoro and other places.

Abstract Background Tanzania has experienced periodic dengue outbreaks with increased incidence since 2010. However, there is limited information on vector dynamics and transmission risk in most parts of the country. This study was conducted to determine Aedes mosquito abundance, larval indices and dengue virus infection rate as risk indicators for DENV transmission in Kinondoni district, Dar es Salaam, Tanzania. Methods A cross-sectional study was conducted in three wards of Kinondoni district in Tanzania between December 2019 and January 2020. In each ward, three streets were randomly selected for adult and immature mosquito sampling. The adult mosquitoes were collected using Mosquito Magnet traps, while mosquito larvae and pupae were inspected in water-holding containers in the selected household compounds. The detection of dengue virus (DENV) in female Aedes mosquitoes was done using a one-step reverse transcription–polymerase chain reaction (RT–PCR) method. Results Of the 1416 adult female mosquitoes collected, Ae. aegypti accounted for 16.8% (n = 238). A total of 333 water-holding containers were inspected and 201 (60.4%) had at least an Aedes larvae or pupae. Water-holding containers supporting the breeding of Aedes larvae and pupae included discarded car tires, flowerpots and small and large plastic containers. The overall House Index, Container Index and Breteau Index were 55.1%, 60.4% and 114.2, respectively. None of the 763 female Aedes mosquitoes tested by RT–PCR was found to be infected with DENV. Conclusion The presence and abundance Ae. aegypti mosquitoes and the large proportion of water-holding containers infested with the mosquito larvae and pupae put residents of Kinondoni district at high risk of DENV transmission. Our findings emphasize the need for continuous mosquito vector surveillance and control to prevent the possibility of future DENV outbreaks in Tanzania.