Seroprevalence of hepatitis A virus infection in Central-West of Tunisia.

Hepatitis A infections still represent a major global health concern. During the past years, a transition pattern of the hepatitis A epidemiology was noted in many parts of the world. In Tunisia, there is not a recent survey on age-specific hepatitis A virus seroprevalence. This study aimed to investigate the seroprevalence of hepatitis A virus infection in Central-West Tunisia, representative of regions with lowest socioeconomic level in the country, before vaccine implementation. Sera obtained from the blood samples of subjects were screened for the detection of hepatitis A virus. The seroprevalence was evaluated by detection of total antibodies to hepatitis A virus using commercially available immunoassay kits. A total of 1379 subjects, aged 5-75 years (mean age: 29.0 ± 17.3 years) were studied. The global anti-hepatitis A virus seroplevalence was 84.7% (95% confidence interval: [82.6-86.5]). A higher hepatitis A virus seroprevalence was showed in subjects aged 10-14 years compared to those aged less than 10 years (50.0% vs. 31.0%). In subjects aged 20-29 years, a rapid increase in the hepatitis A virus prevalence was noted; it reached 97.0%. The seroprevalence of anti-hepatitis A virus differed by zone of residence (81.1% in rural area vs. 72.4% in urban area, p = .005) and increased significantly with lower level of education (p = .019). There was no statistical significant seroprevalence difference between male and female: 84.2% versus 85.2%, respectively. Our study confirm the transition pattern of the hepatitis A virus endemicity in Tunisia from high to intermediate and provide an evaluation of the hepatitis A virus epidemiological situation before vaccine implementation.

Animal bites and post-exposure prophylaxis in Central-West Tunisia: a 15-year surveillance data.

BACKGROUND: Rabies is a disease that still exists in developing countries and leads to more fatalities than other zoonotic diseases. Our study aimed to describe the profile of human exposures to animals over fifteen years and to assess the post-exposure prophylaxis (PEP) practices in the governorate of Kasserine (Tunisia) on pre- and post-revolution (2011). METHODS: We carried out a descriptive study using surveillance data from a region in Central-West Tunisia. All humans exposed to animals, residents in Kasserine Governorate and declared to the regional directorate of primary health care (RDPH) from January 1st, 2004 to December 31st, 2018 were included. RESULTS: A total of 45,564 cases of human exposures to animals were reported over the fifteen-year period of the study with an annual average of 3089.2 ± 403.1. The standardized incidence rate (SIR) of human exposures to animals was 694 per year per 100,000 inhabitants (inh). The most listed offending animal was the dog (91.3%) and the most reported type of exposure was bites (63.7%). The trend in human exposures to animals increased significantly over time. The number of exposures by vaccinated dogs decreased significantly and by unvaccinated and stray dogs increased steeply. When comparing pre-and post-revolution periods, the yearly average of animal exposures post-2011 was significantly greater than the average prior to 2011 (3200 ± 278.5 vs 2952.8 ± 483) (p < 0.001). The yearly average of animal bites post-2011 was significantly greater than the average prior to 2011 (2260.5 ± 372.1 vs 1609.8 ± 217.9) (p < 0.001). The average number of vaccine doses per animal exposure was 2.4. Concerning PEP protocols, protocol A (2 and 3 doses) was indicated in 79% of animal exposures cases. From 2004 to 2018, a downward trend was noted for protocol A (r = - 0.29, p < 0.001) and an upward trend for protocol B (3 and 5 doses) (r = 0.687, p < 0.001). During our study period, 5 fatal cases of human rabies were declared. CONCLUSION: Rabies remains a major public health problem in Tunisia. The political dynamics had an impact on the health care system and rabies control. Preventive measures should be applied adequately to decrease the burden of this disease.

Identification of transmission chains and clusters associated with COVID-19 in Tunisia.

BACKGROUND: The aim of this study was to characterize the transmission chains and clusters of COVID-19 infection in Tunisia. METHODS: All cases were confirmed by Reverse Transcriptase Polymerase Chain Reaction of a nasopharyngeal specimen. Contact tracing is undertaken for all confirmed cases in order to identify close contacts that will be systematically screened and quarantined. Transmission chains were identified based on field investigation, contact tracing, results of screening tests and by assessing all probable mode of transmission and interactions. RESULTS: As of May 18, 2020, 656 cases out of a total of 1043 confirmed cases of Coronavirus disease 2019 belong to 127 transmission chains identified during the epidemic (mean age 42.36 years, Standard deviation 19.56 and sex ratio 0.86). The virus transmission is the most concentrated in the governorate of Tunis (31.5%), Ariana (10.2%) and Ben Arous (10.2%). Virus transmission occurred 50 times (9.72% of secondary transmission events) between two different governorates. A maximum of seven generations of secondary infection was identified, whereas 62% of these secondary infections belong the first generation. A total of 11 "super spreader" cases were identified in this investigation. Four large clusters have been identified. The evolution of secondary cases highlighted two peaks: one in 2nd April and a second in 16 th April whereas imported cases caused local transmission of virus during the early phase of the epidemic. CONCLUSION: Correct contact tracing and early active case finding is useful to identify transmission chains and source of infection in order to contain the widespread transmission in the community.