Abstract
Between March and June 2023, we carried out a pilot study to explore the feasibility of using self-reporting of livestock abortions as a method of syndromic surveillance for Rift Valley fever disease (RVF) in Isingiro District, Uganda. We established a call centre in the office of the District Veterinary Officer which was promoted through stakeholder meetings, media engagement and distribution of sensitization materials.
We collected 200 sera and 269 vagin*l swabs from cattle, sheep and goats that experienced an abortion within a target 14-day period. The apparent IgG seroprevalence of RVF was 38% [95% CI 29 – 47] in cattle, 33% [95% CI 14 – 61] in sheep and 20% [95% CI 12 – 31] in goats. For IgM, sheep showed the highest prevalence at 8% [95% CI 1 – 35], cattle at 2% [95% CI 1 – 6]. Host species was significantly associated with IgG positive status, with cattle having the highest risk of RVF seropositivity (OR = 3 [95%CI: 1 - 7], p = 0.014).
Our results demonstrate the potential for a community led model for collecting abortion alerts through local call centres. If routinely implemented, such syndromic data collection could be used to develop early warning systems and prioritise case investigations. The IgG seroprevalence in our sample is comparable to the levels seen in endemically infected countries, suggesting historical circulation of RVF within the livestock population in this community. Our pilot study demonstrates a proof-of-principle that community-driven reporting of abortions could be used to build a surveillance system for RVF. However, the lack of confirmation of infection through PCR means we cannot draw a firm causal link between the reported abortions and RVF. To build a robust case of abortion surveillance, longitudinal studies are needed to measure seasonal variation in the distribution of abortion cases and incidence of active RVF infections.
Author’s Summary Rift Valley fever disease is a growing zoonotic disease with high potential to disrupt national and international trade and biosecurity. In this work, we contribute to the epidemiology of RVF in Uganda and propose a system for self-reporting of livestock abortions that could provide a pathway to syndromic surveillance for RVF and thus contribute to safer human and animal communities. Engaging communities in setting up call centres for early notification and follow-up of animal diseases is a cost-effective and participatory approach which could be sustainable even with limited resources. Livestock abortions are a common symptom for other diseases like Q-fever, brucellosis, campylobacter among others and therefore, caution should be used when using it as an early warning signal for RVF. Establishing routine reporting could potentially allow for the identification and association of patterns of abortions with different infections. Our pilot study demonstrates the feasibility and active interest and engagement from farmers for such a surveillance system.
Competing Interest Statement
The authors have declared no competing interest.
Funding Statement
Yes
Author Declarations
I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.
Yes
The details of the IRB/oversight body that provided approval or exemption for the research described are given below:
This study is part of the corresponding author's PhD project. We sought and received ethical approval to conduct the research from Makerere University School of Public Health (Reference No: SPH-2022-364), Uganda National Council of Science and Technology (UNCST) (Reference No: A264ES), and Human Biology Research Ethics Committee, University of Cambridge, United Kingdom (Reference No: HBREC.2023.02). Lastly, we sought administrative clearance from Isingiro district local governments’ administration specifically from the Chief Administrative Officer’s office (dated 20th March 2023) for this study to be conducted. Written informed consent from the research participants (Farmers/livestock owners) was obtained for free and voluntary participation in the study. This was after understanding the purpose and costs of the study. During the blood and vagin*l swab collection, we also sought written consent for photographing of the animals for potential detection of RVF and follow-up for actions in future. These photos were only for identification of the animals should the vagin*l swabs turn positive for RVF for control strategies by Isingiro district Veterinary department or MAAIF. To enhance understanding, we translated all the data collection tools and informed consent into the local language (Runyankole) which was the most spoken language in the Isingiro district. This will ease the understanding of the entire project for the participants to consent. We further kept the information confidential by keeping identifying information (telephone numbers) under key and lock but also coded. The data was analysed and published in aggregate form to avoid identification of individual participants. The data is currently stored under key and lock for the five years after publication as stipulated by UNCST.
I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals.
Yes
I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).
Yes
I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable.
Yes
Data Availability
The data that support the findings of this study are publicly available from (https://github.com/abelwalekhwa/Livestock_Abortions) with the identifier(s) as datasets, R code.
