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Q fever (QF) and Rift Valley fever (RVF) are endemic zoonotic diseases in African countries, causing significant health and economic burdens. Accurate prevalence estimates, crucial for disease control, rely on robust diagnostic tests. While enzyme-linked immunosorbent assays (ELISA) are not the gold standard, they offer rapid, cost-effective, and practical alternatives. However, varying results from different tests and laboratories can complicate comparing epidemiological studies. This study aimed to assess the agreement of test results for QF and RVF in humans and livestock across different laboratory conditions and, for humans, different types of diagnostic tests. We measured inter-laboratory agreement using concordance, Cohen's kappa, and prevalence and bias-adjusted kappa (PABAK) on 91 human and 102 livestock samples collected from rural regions in Chad. The serum aliquots were tested using ELISA in Chad, and indirect immunofluorescence assay (IFA) (for human QF and RVF) and ELISA (for livestock QF and RVF) in Switzerland and Germany. Additionally, we examined demographic factors influencing test agreement, including district, setting (village vs. camp), sex, age, and livestock species of the sampled individuals. The inter-laboratory agreement ranged from fair to moderate. For humans, QF concordance was 62.5%, Cohen's kappa was 0.31, RVF concordance was 81.1%, and Cohen's kappa was 0.52. For livestock, QF concordance was 92.3%, Cohen's kappa was 0.59, RVF concordance was 94.0%, and Cohen's kappa was 0.59. Multivariable analysis revealed that QF test agreement is significantly higher in younger humans and people living in villages compared to camps and tends to be higher in livestock from Danamadji compared to Yao, and in small ruminants compared to cattle. Additionally, RVF agreement was found to be higher in younger humans. Our findings emphasize the need to consider sample conditions, test performance, and influencing factors when conducting and interpreting epidemiological seroprevalence studies., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Hungerbühler et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Competing Interests: The authors have declared that no competing interests exist.

Monitoring neoplasms in standardized registries facilitates epidemiologic studies of risk factors for tumor development and predisposition. In an observational study, we determined incidence rates (IR) and malignant tumor incidence rate ratios (IRR) by age, sex, and breed in Swiss dogs using demographic data from the official Swiss dog registration database Amicus. The dataset analyzed included 54'986 tumors diagnosed by histology and cytology in four Swiss veterinary pathology laboratories between 2008 and 2020. Diagnoses were coded according to the Vet-ICD-O-canine-1 system. Most tumors occurred in the skin (n = 19'045; 34.64%), soft tissues (n = 11'092; 20.17%), and mammary glands (n = 7'974; 14.50%). The IRs for all and for malignant tumors were 775/100'000 dog-years at risk (95%CI 764-777) and 338/100'000 dog-years at risk (95%CI 333-342), respectively. Females (850; 95%CI 834-853) had a higher overall tumor IR than males (679; 95%CI 666-684). The highest tumor IR was found at 11 years of age (1'857; 95%CI 1'780-1'867). Potential novel breed-specific predispositions were uncovered, with high IRs for several benign and malignant tumors in Polski Owczarek Nizinnys (overall IR: 3'303; 95%CI 2'502-3'864) and high IRs for malignant tumors in Russian Black Terriers (melanomas: 345; 95%CI 138-708), Field Spaniels (adenocarcinomas: 376; CI95% 138-817), Dogo Argentinos (mast cell tumors: 844; CI95% 591-1'169), King Charles Spaniels and Manchester Terriers (lymphomas: 319; CI95% 137-627 and 302; CI95% 98-704, respectively), Landseers (osteosarcomas: 74; CI95% 15-216), Bouvier des Flandres (hemangiosarcomas: 127; CI95% 26-371), and Bearded Collies and Cane Corso Italianos (gliomas: 91; CI95% 45-162 and 34; CI95% 7-99, respectively). Nordic hunting dogs had the highest (8.08; CI95% 3.55-16.7) and Chihuahueno the lowest cancer IRRs (0.42; 95%CI 0.31-0.57) compared to mixed breeds. In conclusion, the calculated IRs and IRRs revealed previously unknown predisposing factors, including novel breed-specific susceptibilities. The results may have implications for cancer screening, diagnostic work-up, breeding management and oncologic and translational research., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2024 Dhein et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: Antibiotics are increasingly becoming ineffective as antimicrobial resistance (AMR) continues to develop and spread globally-leading to more difficult to treat infections. Countries such as Uganda are still challenged with implementation of AMR related strategies due to data paucity. This includes a lack of data on the prevailing knowledge and awareness of antimicrobial resistance and antibiotic use among farming communities, both commercial and subsistence, which are instrumental in the implementation of targeted interventions. The aim of our study was to assess the knowledge, attitudes and practices on AMR among subsistence and commercial farmers in Wakiso district, central Uganda., Methods: A cross-sectional study was conducted using a semi-structured questionnaire in Wakiso district, Central Uganda in between June and September 2021. Polytomous latent class analyses were performed to group participants based on their responses. Multivariable regression and conditional inference trees were used to determine the association between demographic factors and knowledge on antibiotics and AMR., Results: A total of 652 respondents participated in the study among whom 84% were able to correctly describe what antibiotics are. Subsistence farmers (OR = 6.89, 95% CI [3.20; 14.83]), and to a lesser extent, farming community members which obtained their main income by another business (OR = 2.25, 95% CI [1.345; 3.75]) were more likely to be able to describe antibiotics correctly than individuals involved in commercial farming. Based on the latent class analysis, three latent classes indicating different levels of knowledge on AMR, were found. Subsistence farming, higher educational level and younger age were found to be associated with belonging to a class of better knowledge., Conclusion: The majority of participants were able to correctly describe antibiotics and aware of AMR, however there was some degree of misunderstanding of several AMR concepts. Targeted AMR interventions should improve awareness and also ensure that not only subsistence farmers, but commercial farmers, are included., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Muleme et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: Rapid diagnostics are vital for curving the transmission and control of the COVID-19 pandemic. Although many commercially available antigen-based rapid diagnostic tests (Ag-RDTs) for the detection of SARS-CoV-2 are recommended by the WHO, their diagnostic performance has not yet been assessed in Ethiopia. So far, the vast majority of studies assessing diagnostic accuracies of rapid antigen tests considered RT-PCR as a reference standard, which inevitably leads to bias when RT-PCR is not 100% sensitive and specific. Thus, this study aimed to evaluate the diagnostic performance of Panbio™ jointly with the RT-PCR for the detection of SARS-CoV-2., Methods: A prospective cross-sectional study was done from July to September 2021 in Addis Ababa, Ethiopia, during the third wave of the pandemic involving two health centers and two hospitals. Diagnostic sensitivity and specificity of Panbio™ and RT-PCR were obtained using Bayesian Latent-Class Models (BLCM)., Results: 438 COVID-19 presumptive clients were enrolled, 239 (54.6%) were females, of whom 196 (44.7%) had a positive RT-PCR and 158 (36.1%) were Panbio™ positive. The Panbio™ and RT-PCR had a sensitivity (95% CrI) of 99.6 (98.4-100) %, 89.3 (83.2-97.6) % and specificity (95% CrI) of 93.4 (82.3-100) %, and 99.1 (97.5-100) %, respectively. Most of the study participants, 318 (72.6%) exhibited COVID-19 symptoms; the most reported was cough 191 (43.6%)., Conclusion: As expected the RT-PCR performed very well with a near-perfect specificity and a high, but not perfect sensitivity. The diagnostic performance of Panbio™ is coherent with the WHO established criteria of having a sensitivity ≥80% for Ag-RDTs. Both tests displayed high diagnostic accuracies in patients with and without symptoms. Hence, we recommend the use of the Panbio™ for both symptomatic and asymptomatic individuals in clinical settings for screening purposes., Competing Interests: We, the authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper

Background: Zoonoses can cause a substantial burden on both human and animal health. Globally, estimates of the dual (human and animal) burden of zoonoses are scarce. Therefore, this study aims to quantify the dual burden of zoonoses using a comparable metric, "zoonosis Disability Adjusted Life Years" (zDALY)., Methodology: We systematically reviewed studies that quantify in the same article zoonoses in animals, through monetary losses, and in humans in terms of Disability Adjusted Life Years (DALYs). We searched EMBASE, Web of Science, Scopus, PubMed, and Google Scholar. We excluded articles that did not provide the data to estimate the zDALY or those for which full text was not available. This study was registered at PROSPERO, CRD42022313081., Principal Findings/significance: We identified 512 potentially eligible records. After deduplication and screening of the title and abstract, 23 records were assessed for full-text review. Fourteen studies were included in this systematic review. The data contains estimates from 10 countries, a study at continental level (Asia and Africa), and 2 studies on a global scale. Rabies was the most frequently reported zoonosis where zDALYs were calculated, based on the following included studies: for Kazakhstan 457 (95% CI 342-597), Viet Nam 5316 (95% CI 4382-6244), Asia 1,145,287 (90% CI 388,592-1,902,310), Africa 837,158 (90% CI 283,087-1,388,963), and worldwide rabies 5,920,014 (95% CI 1,547,860-10,290,815). This was followed by echinococcosis, the zDALYs in Peru were 2238 (95% CI 1931-2546), in China 1490 (95% CI 1442-1537), and worldwide cystic echinococcosis 5,935,463 (95% CI 4,497,316-7,377,636). Then, the zDALYs on cysticercosis for Mozambique were 2075 (95% CI 1476-2809), Cameroon 59,540 (95% CR 16,896-101,803), and Tanzania 34,455 (95% CI 12,993-76,193). Brucellosis in Kazakhstan were 2443 zDALYs (95% CI 2391-2496), and brucellosis and anthrax in Turkey 3538 zDALYs (95% CI 2567-6706). Finally, zDALYs on leptospirosis in New Zealand were 196, and Q fever in Netherlands 2843 (95% CI 1071-4603). The animal burden was superior to the human burden in the following studies: worldwide cystic echinococcosis (83%), brucellosis in Kazakhstan (71%), leptospirosis in New Zealand (91%), and brucellosis, and anthrax in Turkey (52%). Countries priorities on zoonoses can change if animal populations are taken into consideration., Competing Interests: The authors have declared that no competing interests exist.

Background: COVID-19 is an ongoing public health pandemic regardless of the countless efforts made by various actors. Quality diagnostic tests are important for early detection and control. Notably, several commercially available one step RT-PCR based assays have been recommended by the WHO. Yet, their analytic and diagnostic performances have not been well documented in resource-limited settings. Hence, this study aimed to evaluate the diagnostic sensitivities and specificities of three commercially available one step reverse transcriptase-polymerase chain reaction (RT-PCR) assays in Ethiopia in clinical setting., Methods: A cross-sectional study was conducted from April to June, 2021 on 279 respiratory swabs originating from community surveillance, contact cases and suspect cases. RNA was extracted using manual extraction method. Master-mix preparation, amplification and result interpretation was done as per the respective manufacturer. Agreements between RT-PCRs were analyzed using kappa values. Bayesian latent class models (BLCM) were fitted to obtain reliable estimates of diagnostic sensitivities, specificities of the three assays and prevalence in the absence of a true gold standard., Results: Among the 279 respiratory samples, 50(18%), 59(21.2%), and 69(24.7%) were tested positive by TIB, Da An, and BGI assays, respectively. Moderate to substantial level of agreement was reported among the three assays with kappa value between 0 .55 and 0.72. Based on the BLCM relatively high specificities (95% CI) of 0.991(0.973-1.000), 0.961(0.930-0.991) and 0.916(0.875-0.952) and considerably lower sensitivities with 0.813(0.658-0.938), 0.836(0.712-0.940) and 0.810(0.687-0.920) for TIB MOLBIOL, Da An and BGI respectively were found., Conclusions: While all the three RT-PCR assays displayed comparable sensitivities, the specificities of TIB MOLBIOL and Da An were considerably higher than BGI. These results help adjust the apparent prevalence determined by the three RT-PCRs and thus support public health decisions in resource limited settings and consider alternatives as per their prioritization matrix., Competing Interests: The authors have declared that no competing interests exist.

Germany has been officially free of bovine tuberculosis since 1996. However, in the last years there has been an increase of bovine tuberculosis cases, particularly in the southern part of Germany, in the Allgäu region. As a consequence a one-time tuberculosis surveillance program was revisited with different premortal and postmortal tests. The aim of this paper was to estimate diagnostic sensitivities and specificities of the different tests used within this surveillance program. In the absence of a perfect test with 100% sensitivity and 100% specificity, thus in the absence of a gold standard, a Bayesian latent class approach with two different datasets was performed. The first dataset included 389 animals, tested with single intra-dermal comparative cervical tuberculin (SICCT) test, PCR and pathology; the second dataset contained 175 animals, tested with single intra-dermal cervical tuberculin (SICT) test, Bovigam® assay, pathology and culture. Two-way conditional dependencies were considered within the models. Additionally, inter-laboratory agreement (five officially approved laboratories) of the Bovigam® assay was assessed with Cohen's kappa test (21 blood samples). The results are given in posterior means and 95% credibility intervals. The specificities of the SICT test, SICCT test, PCR and pathology ranged between 75.8% [68.8-82.2%] and 99.0% [96.8-100%]. The Bovigam® assay stood out with a very low specificity (6.9% [3.6-11.1%]), though it had the highest sensitivity (95.7% [91.3-99.2%]). The sensitivities of the SICCT test, PCR, SICT test, pathology and culture varied from 57.8% [48.0-67.6%] to 88.9% [65.5-99.7%]. The prevalences were 19.8% [14.6-26.5%] (three-test dataset) and 7.7% [4.2-12.3%] (four-test dataset). Among all pairwise comparisons the highest agreement was 0.62 [0.15-1]). In conclusion, the specificity of the Bovigam® assay and the inter-laboratory agreement were lower than expected.

For swine dysentery, which is caused by Brachyspira hyodysenteriae infection and is an economically important disease in intensive pig production systems worldwide, a perfect or error-free diagnostic test ("gold standard") is not available. In the absence of a gold standard, Bayesian latent class modelling is a well-established methodology for robust diagnostic test evaluation. In contrast to risk factor studies in food animals, where adjustment for within group correlations is both usual and required for good statistical practice, diagnostic test evaluation studies rarely take such clustering aspects into account, which can result in misleading results. The aim of the present study was to estimate test accuracies of a PCR originally designed for use as a confirmatory test, displaying a high diagnostic specificity, and cultural examination for B. hyodysenteriae. This estimation was conducted based on results of 239 samples from 103 herds originating from routine diagnostic sampling. Using Bayesian latent class modelling comprising of a hierarchical beta-binomial approach (which allowed prevalence across individual herds to vary as herd level random effect), robust estimates for the sensitivities of PCR and culture, as well as for the specificity of PCR, were obtained. The estimated diagnostic sensitivity of PCR (95% CI) and culture were 73.2% (62.3; 82.9) and 88.6% (74.9; 99.3), respectively. The estimated specificity of the PCR was 96.2% (90.9; 99.8). For test evaluation studies, a Bayesian latent class approach is well suited for addressing the considerable complexities of population structure in food animals.

Background: The diagnosis of canine echinococcosis can be a challenge in surveillance studies because there is no perfect gold standard that can be used routinely. However, unknown test specificities and sensitivities can be overcome using latent-class analysis with appropriate data., Methodology: We utilised a set of faecal and purge samples used previously to explore the epidemiology of canine echinococcosis on the Tibetan plateau. Previously only the purge results were reported and analysed in a largely deterministic way. In the present study, additional diagnostic tests of copro-PCR and copro-antigen ELISA were undertaken on the faecal samples. This enabled a Bayesian analysis in a latent-class model to examine the diagnostic performance of a genus specific copro-antigen ELISA, species-specific copro-PCR and arecoline purgation. Potential covariates including co-infection with Taenia, age and sex of the dog were also explored. The dependence structure of these diagnostic tests could also be analysed., Principle Findings: The most parsimonious result, indicated by deviance-information criteria, suggested that co-infection with Taenia spp. was a significant covariate with the Echinococcus infection. The copro-PCRs had estimated sensitivities of 89% and 84% respectively for the diagnoses of Echinococcus multilocularis and E. granulosus. The specificities for the copro-PCR were estimated at 93 and 83% respectively. Copro-antigen ELISA had sensitivities of 55 and 57% for the diagnosis of E. multilocularis and E. granulosus and specificities of 71 and 69% respectively. Arecoline purgation with an assumed specificity of 100% had estimated sensitivities of 76% and 85% respectively., Significance: This study also shows that incorporating diagnostic uncertainty, in other words assuming no perfect gold standard, and including potential covariates like sex or Taenia co-infection into the epidemiological analysis may give different results than if the diagnosis of infection status is assumed to be deterministic and this approach should therefore be used whenever possible.