Risk based serological survey of Rift Valley fever in Tunisia (2017-2018).

Rift Valley fever (RVF) has been reported in the sub-Saharan region of Africa, Egypt and Arabian Peninsula - Yemen and Saudi Arabia, over the past 20 years and is a threat to both the animal and human populations in Tunisia. Tunisia is considered as a high-risk country for the introduction of RVF due to the informal movements of diseased animals already reported in the neighboring countries. The objective of this study was to assess the status of RVF in small ruminants and camels in Tunisia. A risk-based serological survey was conducted to evaluate the presence of RVF based on spatial qualitative risk analysis (SQRA). Samples were collected from small ruminants (sheep and goats) (n = 1,114), and camels (n = 173) samples, belonging to 18 breeders in 14 governorates between November 2017 and January 2018. Samples were tested using an RVF specific multispecies competitive ELISA. Out of the 1,287 samples tested for the presence of RVF IgG antibodies by ELISA, only one positive sample 0.07% (1/1 287) was detected but not confirmed with the virus neutralization test (VNT) used for confirmation. So far, no RVF outbreaks have been reported in Tunisia and our study confirmed the absence of RVF in livestock up to January 2018. Further investigations are needed to confirm the RVF-free status of Tunisia today.

Temporal and spatial distributions of animal and human rabies cases during 2012 and 2018, in Tunisia.

Rabies is one of the most important zoonosis in Tunisia. In the last 6 years, a dramatic increase in the number of cases in animals had raised concern about the transmission dynamics of rabies and the effectiveness of established control measures. For a better understanding of the epidemiological features of rabies in Tunisia, data on animal and human rabies cases and post-exposure prophylaxis (PEP) protocol, for the period from 2012 to 2018, were analysed to describe the spatial and the temporal distributions of the disease and to guide targeted rabies control measures. Thus, the analysed data have shown that 2,642 animal and 25 human rabies cases were recorded between 2012 and 2018; only few case numbers were reported in wildlife. Time-related distribution showed that the incidence of dog rabies increases over the period of study, from 24,8/100,000 dog population in 2012 to 35,2/100,000 dog population in 2018. Dog seems to be the main reservoir of rabies as it accounted for more than 59% of the animal confirmed cases and the source for more than 80% of the human confirmed cases. Geographical distribution of animal rabies cases revealed the presence of clusters in the North and the Center of Tunisia; only a little number of animal cases were reported in the South. In contrast, the overall human rabies incidence was 0.03 per 100,000 population, during the period of the study. We have found that the incidence of human rabies increases by 13.6% from 2012 to 2015 and drops steadily by 23.41% over the second period (2015 to 2018). A high number of PEP was recorded during the 7-year period, with an average of 360 PEP per 100,000 inhabitants per year. Spatial analysis revealed the presence of clusters of PEP in the Northern and Central governorates. The present study pointed out the need to review the control strategy of rabies in Tunisia and conduct further studies on dog population to provide the basis for a new and efficacious policy of interventions and control program for rabies.

Respiratory syndrome coronavirus-2 response: Microbiota as lactobacilli could make the difference.

Coronavirus disease 2019 (COVID-19) is caused by respiratory syndrome coronavirus qualified as SARS-CoV-2. Viral penetration requires binding of the viral spike (S) protein to a specific cellular receptor (ACE2) highly expressed in a nasal goblet and ciliated cells. In several countries, the COVID-19 evolution was relatively benign compared to others and despite noncompliance with health recommendations on several occasions. In this overview, we attempt to define the criteria that could explain such a difference. Among these criteria, the specificity of Lactobacillus genus strains, as a part of nasal microbiota, could play a role of a barrier against viral penetration and could strengthen the host's immune system in some populations rather than others. In fact, several studies have shown the role of lactic acid bacteria, including lactobacilli, in the prevention of viral respiratory infections. This could provide important information on a possible mechanism of the virus spreading.

Contamination of Fishery Products with Mercury, Cadmium, and Lead in Tunisia: Level's Estimation and Human Health Risk Assessment.

The levels of metallic trace elements were determined in fishery products sampled from Tunisian fishing ports. Mean concentrations were 0.20 ± 0.01, 0.05 ± 0.01, and 0.10 ± 0.01 mg/kg in fish flesh for Hg, Cd, and Pb, respectively. The mean concentrations of these elements were below regulatory thresholds; however, we also detected some specimens with higher levels. The mercury level showed a significant difference between fish categories, region, and year of sampling (p < 0.05). Samples from the center sites had the highest levels of Pb (0.17 ± 0.03 mg/kg; range 0.10; 0.22 mg/kg). Temporal analysis of Pb showed a significant difference between sampling year (p < 0.05). In addition, distribution among fish categories was statistically significant (p = 0.046). The rates of samples exceeding limits of Hg, Cd, and Pb were 5.3, 2.6, and 0.4%, respectively. Through the above results, the maximum weekly and monthly intakes for fish flesh consumption could not exceed the set limits. These data were important to inform consumers about fish content and the risk generated by some of these species.

Evaluation of human resources needed and comparison with human resources available to implement emergency vaccination in case of foot and mouth disease outbreaks in Tunisia.

Foot and mouth disease (FMD) is a highly contagious viral disease that affects domestic and wild artiodactyl animals and causes considerable economic losses related to outbreak management, production losses and trade impacts. In Tunisia, the last FMD outbreak took place in 2018-2019. The effectiveness of control measures implemented to control FMD depends, in particular, on the human resources used to implement them. Tunisia has the ultimate objective of obtaining OIE status as 'FMD-free with vaccination'. The aim of this study was to determine and compare the necessary and available human resources to control FMD outbreaks in Tunisia using emergency vaccination and to assess the gaps that would play a role in the implementation of the strategy. We developed a resources-requirement grid of necessary human resources for the management of the emergency vaccination campaign launched after the identification of a FMD-infected premises in Tunisia. Field surveys, conducted in the 24 governorates of Tunisia, allowed quantifying the available human resources for several categories of skills considered in the resources-requirement grid. For each governorate, we then compared available and necessary human resources to implement vaccination according to eight scenarios mixing generalised or cattle-targeted vaccination and different levels of human resources. The resources-requirement grid included 11 tasks in three groups: management of FMD-infected premises, organisational tasks and vaccination implementation. The available human resources for vaccination-related tasks included veterinarians and technicians from the public sector and appointed private veterinarians. The comparison of available and necessary human resources showed vaccination-related tasks to be the most time-consuming in terms of managing a FMD outbreak. Increasing the available human resources using appointed private veterinarians allowed performing the emergency vaccination of animals in the governorate in due time, especially if vaccination was targeted on cattle. The overall approach was validated by comparing the predicted and observed durations of a vaccination campaign conducted under the same conditions as during the 2014 Tunisian outbreak. This study could provide support to the Tunisian Veterinary Services or to other countries to optimise the management of a FMD outbreak.