Viral hepatitis E is an acute viral disease present on a global scale, but it is mainly observed in East and South Asia [1][2]. It is a major concern in growing public health and constitutes an emerging disease whose incidence increases significantly in certain populations and regions [1][2]. About 60% to 75% of emerging diseases in humans are zoonoses, which implies that they are transmitted from animals to humans and vice versa [1][3]. A large number of domestic and wild animals and pathogens play a well-identified role in the ecology of diseases transmissible to humans, which cannot be dissociated from its ecosystem: this is the case for viral hepatitis E [3]. The hepatitis E virus (HEV) is responsible for more than 50% of acute viral hepatitis in adults in endemic countries and about 1% in non-endemic countries [4][5]. Although most HEV infections are benign, infections in pregnant women can progress to fulminant hepatitis, especially in the third trimester, with a high mortality rate of 15% - 20% [4][5]. HEV is mainly transmitted enterically, but cases of parenteral transmission through blood have been reported [6]. There are four major genotypes of HEV. Genotypes 1 and 2, strictly human, are predominant in Asia, Africa and Central America, and are mainly transmitted through contaminated water [7]. Genotypes 3 and 4, transmitted zoonotically, are more common in industrialized countries and are associated with contaminated food consumption [7]. Their transmission by transfusion has been reported, notably in India. The large animal reservoir of these viruses, including pigs, wild boars, deer and rabbits, explains a transmission related to the consumption of insufficiently cooked food. Products of porcine origin, game but also shellfish, fruits and vegetables contaminated by livestock effluents, or irrigation water are concerned [8]. Genotypes 3 and 4 can also be transmitted through direct contact with infected animals. Transmission by transfusion has been documented in Japan (genotypes 3 and 4) and several European countries (genotype 3) including France, the UK, Germany and Spain [7][9]. It is also responsible for chronic viral hepatitis in immunocompromised patients in the countries of the Northern Hemisphere and mortality in pregnant women in countries with a low level of hygiene [10]. HEV infection may also aggravate underlying hepatopathies. Although the HEV has been discovered for more than 30 years, the pathophysiology of infection and interactions between the HEV and its host are still incompletely known [10].

Every year, an estimated 20 million infections with HEV occur worldwide, resulting in some 3.3 million symptomatic cases of hepatitis E that would have caused about 44,000 deaths in 2015 (or 3.3% of the mortality due to viral hepatitis [11][12]. The hepatitis E virus (HEV) is therefore the causative agent of some of the acute or fulminant hepatitis that occurs mainly in developing countries (Africa, Asia) or the HEV of genotype 1 seems to present an endemic profile punctuated by epidemic outbreaks often linked to population movements (climate disaster or conflicts) [13]. Recently, it has been shown that this virus was widely distributed in animal reservoirs (genotype 3 and 4) and the cause of a large number of zoonotic infections both in northern and southern countries [13]. In most cases, it is a spontaneously resolved infection with rapid viral clearance, but it can evolve into more severe forms with a mortality level ranging from 1 to 4% in the general population and nearly 20% in pregnant women during outbreaks [13]. The prevalence varies worldwide (5% to 15% in Japan, Western Europe, USA). In West Africa, HEV seroprevalence ranges from 8% in Sierra Leone to 22% in Ghana [14]. The prevalence of the disease among pregnant women in West Africa is 16.40 (95% CI: 11.39 - 21.41), in North Africa 50.01 (95% CI: 4.43 - 95.58), in East Africa 35.0 (95% CI: 21.74 - 48.26), in Central Africa 10.45 (95% CI: 3.02 - 17.88) [15]. In Burkina Faso, the prevalence among blood donors was 19.1% in 2012 [16] and 18.2% in cases of febrile jaundice in 2019 (Muraz Center) [17], the molecular epidemiology of HEV or the presence of this virus in the main animal reservoir, which pigs constitute. In addition, the ignorance of the population as to the causes of this foodborne infection is a risk factor that cannot be ignored [16][18]-[21].

Hepatitis E virus (HEV) causes acute viral hepatitis and has two distinct epidemiological profiles [22]-[24]. Genotypes 1 and 2 cause outbreaks in high-prevalence areas, with high morbidity and mortality among pregnant women and young children, while genotypes 3 and 4 cause less symptomatic cases in low-prevalence areas [22]-[24]. Contamination with genotypes 1 and 2 typically occurs in developing countries via the fecal-oral route, while genotypes 3 and 4 are transmitted in developed countries through the consumption of contaminated pork or other meats [22]-[24]. Catastrophic epidemiological data have been reported in Bangladesh, with mortality rates of more than 9% of pregnant women due to hepatitis E [25]-[27]. The difference in severity between regions could be linked to virological and socio-economic factors. Viral hepatitis E presents an increased risk of obstetric complications and maternal mortality in areas of high endemic [23][27][28]. She has a poor prognosis in pregnant women in developing countries [23][27][28]. This study aims to fill the data gap on viral hepatitis E (HVE) in pregnant women in Burkina Faso, a subject still little explored. Awareness on prevention measures remains insufficient, making necessary a better understanding of local dynamics. The general objective is to determine the seroprevalence of HVE among pregnant women attending the prenatal care service at Saint Camille Hospital in Ouagadougou, while analyzing the socio-demographic characteristics and associated transmission factors.

This study revealed that 50% of pregnant women in Burkina Faso, particularly in Ouagadougou, had been in contact with the hepatitis E virus (HEV) and had an IgG antibody. But, we cannot invalidate or confirm the presence of a contact or an old one. This high prevalence observed in our study highlights the importance of viral hepatitis E (HVE) as a public health problem. In Burkina Faso, the only study that was carried out on pregnant women is that of Florence et al. [19] who had found a prevalence of 10.6%. This difference is certainly related to the diagnostic tests used. In Africa, this prevalence is more or less similar to the one reported by Dagnew et al. [15] in North Africa which was 50.2%. However, it is different and higher than those obtained by studies conducted in Tunisia (4.3%), Gabon (14.1%), Ghana (28.7%) and Sudan (41%) and in Asia (in China (11.1%) and in India (33.6%)) [19.49 - 52]. It is lower than that found in Egypt (84.3%) [31]. Our high prevalence could be attributed to several factors. Firstly, the hygienic-sanitary conditions: as viral hepatitis E has the fecal-oral route as its main mode of transmission, this could explain the high risk of transmission as demonstrated by the studies of Traoré et al. [32] in Burkina Faso and Amanya et al. [33] in Uganda. Secondly, cooking practices and food handling play a crucial role in the transmission of the virus [16][21]. The displacement of the population due to conflicts, climate disasters could favor the spread of the virus due to temporary and often unsanitary living conditions [34]. Indeed, Burkina Faso has been experiencing insecurity in the Sahel region for a few years, causing populations and their belongings to move to regions where peace reigns, as a result, these movements bypass human and animal surveillance measures.

Regarding our study, only the consumption of the intestines of animals that were more associated with the transmission of viral hepatitis E in pregnant women. For several reasons, the consumption of intestines from animals can increase the risk of viral hepatitis E (HVE) infection. The majority of our respondents claim to use already prepared meat instead of cooking with family, because they say it’s faster. Insufficient cooking can allow the virus to remain intact, increasing the risk of contamination. To avoid this, it is essential to cook the intestines well in order to eliminate the virus. Indeed, Meng [35] showed that the consumption of lightly cooked or raw offal such as liver or spleen can be the cause of contamination. Lopez-Lopez et al. [36] reported contaminations related to the consumption of lightly cooked pork. Pigs and other animals can be carriers of EHV. The consumption of intestines from infected animals could transmit the virus to humans as reported by Renou et al. [31] in France, Berto et al. [37] in Vietnam, Bari et al. [38] in Ethiopia, Diouara et al. [24] in Senegal. The identification of the consumption of animal intestines as a main risk factor highlights a specific food transmission mode, particularly relevant in the Burkinabe context.

The present study was conducted on pregnant women with a primary data collection. The data collection was largely based on the responses of the interviewees on questions related to the transmission of viral hepatitis E that could lead to memory bias (respondents may not accurately recall events or their dietary practices) or social desirability (participants may give responses that they find more acceptable or consistent with social expectations rather than reporting reality). Since the collection is limited to one structure, this does not allow extrapolation to all other hospitals or to the general population. The serological test used only informs us about the individual’s contact with the pathogen, but does not allow us to confirm that the individual is sick. Cross-sectional design prevents causal inference and IgG alone cannot distinguish distant infection from recent infection.

The overall objective of this work was to study the seroprevalence and associated factors of viral hepatitis E in pregnant women receiving prenatal care at Saint Camille Hospital in Ouagadougou, Burkina Faso. It appears that viral hepatitis E is indeed present in pregnant women with a seroprevalence of 50%. The factors associated with the occurrence of the disease in pregnant women include, among others, the consumption of fresh milk, the consumption of products made from offal, of faith, meat from pigs, cattle or sheep not sufficiently cooked. The hepatitis E virus therefore circulates among the pregnant women surveyed. The seroprevalence obtained indicates the need to reduce poverty, promiscuity and insalubrity while promoting a healthy lifestyle. Systematic screening for viral hepatitis E in pregnant women is necessary in Burkina Faso. Monitoring of disease in animals through awareness of good hygienic practices is recommended. Furthermore, in order to promote transfusion safety, it is essential to screen blood donors for hepatitis E virus. The combination of other confirmatory tests such as molecular biology with serological ELISA is imperative.

Before the data collection, the Ethics Committee for Health Research (CERS) of Burkina Faso by Deliberation No 2024-07-223 of 23 July 2024 had approved the ethical component of this research project. In addition, the HOSCO Institutional Ethics Committee had also given its approval by Deliberation No 2024-07-003 of July 12, 2024. Written informed consent for participation in the study was obtained from participants.

The authors thank the pregnant women for their collaboration and participation in this study. The work was carried out thanks to the financial support of Microbiology-Epidemiology, Zoonosis and One Health Laboratory (LMEZOH), Health Science Research Institute (IRSS), National Centre for Scientific and Technological Research (CNRST) of Burkina Faso.