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Prevalence of HBV and HCV Markers among Patients Attending the Saint Camille Medical Centre in Ouagadougou



M.T.A. Zeba, C.A.T. Ouattara, S.D. Karou, C. Bisseye, D. Ouermi, F.W. Djigma, T. Sagna, V. Pietra, R. Moret, J. Nikiema and J. Simpore
 
ABSTRACT

HCV and HBV cause annually, 2000 deaths from liver cancer in Burkina Faso. In this country, serological screening of hepatitis viruses B and C is only systematic among blood donors. The aims of this study were; (1) to investigate the reasons for the prescription of the screening for hepatitis B and C; (2) to determine HCV and HBV prevalence among 462 patients attending the Saint Camille Centre and (3) to identify patients with acute hepatitis or with chronic hepatitis for better monitoring. From February to May 2012, 462 patients attending the laboratory of the Saint Camille Medical Centre with viral hepatitis suspicion were screened. The hepatitis B and C serological markers were detected through Enzyme Immuno Assay (EIA) technique using commercial reagent kits. The clinical symptoms were also recorded for each patient. The results revealed that, the main clinical symptoms that prompted physicians to request HBV and HCV screenings were: asthenia (39.4%), anorexia (21.2%), abdominal pains (19.0%), nausea (10.4%), others (10.0%). The prevalence of HbsAg was 29.4% among the screened people. Patients with acute hepatitis B, active chronic hepatitis B and non-active chronic hepatitis B represented 11.2, 2.2 and 16.0%, respectively. The acquisition of immunity against HBV after vaccination was attempted for 11.7% people. HCV prevalence was 3.9% and its coinfection with HBV was 2.2%. This study showed a high prevalence for hepatitis B and C among patients attending Saint Camille Medical Centre. Without hygiene education and HBV/HCV prevention, viral hepatitis infection will become a serious public health problem in Burkina Faso.

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M.T.A. Zeba, C.A.T. Ouattara, S.D. Karou, C. Bisseye, D. Ouermi, F.W. Djigma, T. Sagna, V. Pietra, R. Moret, J. Nikiema and J. Simpore, 2012. Prevalence of HBV and HCV Markers among Patients Attending the Saint Camille Medical Centre in Ouagadougou. Pakistan Journal of Biological Sciences, 15: 484-489.

DOI: 10.3923/pjbs.2012.484.489

URL: https://scialert.net/abstract/?doi=pjbs.2012.484.489
 
Received: July 06, 2012; Accepted: September 14, 2012; Published: October 06, 2012

INTRODUCTION

In developing countries, mainly in West Africa, viral hepatitis is a serious health problem (Hoffmann and Thio, 2007; Bosan et al., 2010). In this region, the prevalence of Hepatitis B Virus (HBV) and Hepatitis C Virus (HCV) are very high compared with Western Europe, Australia and North America (CDC, 2008) and most of those infected people are chronic carriers. But this prevalence varies from one country to another in Africa (Ouermi et al., 2009). Also, coinfection with both viruses is very common because of certain risk practices such as female genital mutilation, circumcision, ethnic scarifications, forced marriage, levirate etc. (Simpore et al., 2011; Kazmi et al., 2003). Most of people infected with HBV spontaneously eliminate the virus after six months but some ones become chronic carriers and can develop chronic hepatitis.

In many African countries, viral hepatitis screening is not systematic and many peoples are infected by HBV and HCV without knowing it. This ignorance contributes to the spread of these viruses by parenteral route, sexual and mother-child transmission (Ilboudo et al., 2010). These two viruses lead to any physical disturbs as abdominal pains, nausea, anorexia, asthenia and, in some cases, to hepatocellular carcinoma (Kao and Chen, 2002; Liu and Fan, 2007; Chakraborty et al., 2012). The coinfection with HBV and HCV is, in sub-Saharan Africa, the second cause of cancer in males and the third cause of cancer in females (Parkin et al., 2008).

In Burkina Faso, HBV prevalence is higher than 8% when HCV infects about 2% of the population (Simpore et al., 2006) and both viruses cause annually 2000 deaths from liver cancer in the country (Pietra et al., 2008). The objectives of this study were (1) To investigate the clinical signs that allowed physicians to prescribe screening for hepatitis B and C, (2) To determine HCV and HBV prevalence among 462 patients attending the Saint Camille Medical Centre (SCMC) and (3) To identify patients with acute hepatitis or with chronic hepatitis for better monitoring.

MATERIALS AND METHODS

Patients’ recruitment: This study concerned 462 patients of 2-72 years old (mean 33.2±11.3), who came to the laboratory of the SCMC for hepatitis B or/and hepatitis C screening from February-May 2012. All the patients, freely, agreed to answer our questionnaire referring to their clinical symptoms: asthenia, anorexia, abdominal pains, nausea. In the SCMC, HBV and HCV screening are usually done with rapid ELISA test on blood samples, previously collected in EDTA impregnated tubes.

Serological test: The collected blood samples were centrifuged to separate the serum which was used for screenings. HBV serological markers (HbsAg, HbsAb, HbeAg, HbeAb and HbcAb) and anti-HCV were detected through Enzyme Immuno Assay (EIA) technique using commercial diagnostic kits (ACON Laboratories, Inc., USA) as described by Buseri et al. (2010).

Statistical analysis: The prevalence of each serological marker was established according to sex and age group. The collected data were analyzed by standard software SPSS-10 and EpiInfo-6. Statistical significance was set at p<0.05.

Ethical aspect: The ethics committee of the Center of Molecular Biology Research (CERBA) and of Saint Camille Medical Centre (CMSC) gave its approval for this study.

RESULTS

The present study concerned 462 patients including 242 (52.4%) males and 220 (47.6%) females (sex ratio: 1.58). The ages ranged from 2-72 years (mean 33.2±11.3). Regarding the clinical symptoms or the reasons for the screening, 39.4% (182/162) suffered from asthenia, 21.2% (98/462) from anorexia, 19.0% (88/462) from abdominal pains and 10.4% (48/462) from nausea (Table 1). Other reasons involving prenatal screening, vaccination, concerned 46 patients (10.0%).

Table 2 showed that 136 individuals (29.4%) were positive for HbsAg. According to sex, HbsAg prevalence was higher in females (30.0%) than in males (28.9%) but the difference was not statistically significant (p>0.05). Among the screened individuals 11.2% (52/462) had acute hepatitis B and 2.2% (10/462) had chronic active hepatitis B (Table 3). Seventy-four patients (16.0%) were healthy carriers of hepatitis B virus. Vaccinal immunity was observed in 54 persons (11.7%) while 68 (14.7%) had never been infected with HBV.

Table 1: Symptoms that prompted the request for viral hepatitis screening

Table 2: HBV and HCV markers prevalence according to age
HBV: Hepatitis B virus, HBC: Hepatitis C virus, HbsAg: Hbs antigen, HbsAb: Anti Hbs antibody, HbeAg: Hbe antigen, HbeAb: Anti Hbe antibody, HbcAb: Anti Hbc antibody, HcvAb: Anti Hcv antibody

Table 3: Prevalence of HBV markers according to the natural history of HBV
aAll markers positive, bPositive for HbsAg, HbeAg and HbcAb after six months, cPositive for HbsAg, HbeAb and HbcAb after six months, dPositive for HbsAb, HbeAb, HbcAb or HbsAb and HbcAb, ePositive for Only HbsAb, fNegative for all markers

Table 4: Comparison of HBV and HCV prevalence according to gender
αp-value comparing male/female gender

The prevalence of HCV was 3.9% (18/462). No infection with HCV was observed in the age group<19 years but the highest prevalence was observed among individuals aged from 20 to 29 years (Table 2). No significant difference was observed according to gender for HCV infection (p = 0.783). Ten persons (2.2%) were coinfected with HBV and HCV (Table 4).

DISCUSSION

Burkina Faso, located in Sub-Saharan Africa, is considered as a high endemicity area of HBV infection (more than 8% of the population is HBV carriers) and a low HCV prevalence region (less than 2%) (WHO, 2004; Pietra et al., 2008).

This study is different from those previously conducted in the SCMC (Ilboudo et al., 2003, 2010; Simpore et al., 2004, 2006). Indeed, these previous studies involved only pregnant women or mothers/children or people infected by HIV. In our investigations, the sample consisted of people with symptoms suspecting hepatitis such as asthenia, anorexia, abdominal pains and nausea and so on.

In this study, it has been found that the main reason for HBV and HCV screening was “suspicion of viral hepatitis”. Indeed, the prescriptions orders were asthenia (39.4%), anorexia (21.2%), abdominal pains (19.0%) and nausea (10.4%). The others reasons including pregnancy, post vaccination test and voluntary testing, represented 10.0%. But this trend was not observed in other studies. Agbenu et al. (2008) reported in their study that, the indication “screening for HBV” represented more than 40% of the medical indications declared by the prescribing physicians while the indication “suspected hepatitis” accounted for less than 20%.

In 2006, the vaccination against hepatitis B began in our country for newborns but the prevalence of anti-Hbs is low in the general population. Our findings showed that only 11.7% of screened people had immunity against HBV after vaccination. This rate is very low compared to those found in Italy (more than 90%) (Paola et al., 2009) and in Germany (more than 80%) (Schenkel et al., 2008). Detection of HBV markers plays an important role in the biological monitoring of HBV infection (Galula et al., 2006) and the presence of HbsAg in blood is considered a risk factor for hepatocellular carcinoma by some epidemiological studies. The prevalence of HbsAg found was 29.4%. However, this prevalence is not representative of the general population of Burkina Faso and this is very high compared to those previously reported by Pietra et al. (2008), Ilboudo et al. (2007) and Simpore et al. (2004) which were respectively 12.1% among health personnel, 16.7% among HIV positive patients and 9.1% among pregnant women. This difference could be related to the study populations. In this study, the HBV prevalence among women was 30.0%. This rate (30.0%) is higher than those found among women, respectively by Ilboudo et al. (2003) in Ouagadougou (12.04%), Simpore et al. (2006) in Ouagadougou (11.6%), Otegbayo et al. (2008) in Nigeria (11.9%), Nagu et al. (2008) in Tanzania (17.3%) as well as Balan et al. (1998) in Romania (36.7%). However, our results are lower than those of Lukhwareni et al. (2009) in South Africa (40.6%). These differences in prevalence show that hepatitis B infection constitutes a serious public health problem in Sub-Saharan Africa and over the world.

It has also been noticed that more than 18.0% of peoples screened for HBV were chronically infected with this virus. Among these chronic carriers, 2.2% who have HbsAg positive and HbeAg positive, have active hepatitis B. According to some studies, AgHbe which indicates the high viral replication is a bad prognosis for the evolution of liver disease in HBV chronic carriers (Hwai et al., 2002). In Burkina Faso, without considering HCV, more than 1000 peoples die every year for liver cancer due to HBV infection (Pietra et al., 2008). The majority of HBV chronic carriers were infected during childhood and some authors reported that HBV infection in children is transmitted during the perinatal period (Zanetti et al., 2008). About 90% of children infected by the perinatal route become chronic carriers of the virus, because of their immature immune system (Michielsen et al., 2005). The rate of HBV perinatal transmission is over 20% (Onakewhor et al., 2001; El-Magrahe et al., 2010). This rate would increase if the mother is HbeAg-positive (Hou et al., 2001; Wiseman et al., 2009; Ilboudo et al., 2010). So, in Burkina Faso, about 11% of pregnant women are HBV chronic carriers (Simpore et al., 2006; Ilboudo et al., 2010) and the rate of HBV antennal transmission is 37.1% (Sangare et al., 2009).

In this report, females (30.0%) were more infected by HBV than males (28.9%) but the difference was not significant (p>0.05). Some authors have previously reported that men were more infected with HBV than women. Indeed, Tsay et al. (2009) showed in their study that HBV prevalence was 21.7% in males versus 17.2% in females. The same authors also suggested that, the fact that most of HBV infections occur during childhood and the fact that there is a high immunity in females than males, contribute to HbsAg clearance in females. However, the prevalence reported in this study was in contrast with the reports of Tsay et al. (2009) . So, our findings suggest that, like HIV, HBV epidemiology has a feminine face in Sub-Saharan Africa. Indeed, because of factors such as physiological predispositions (more surface contact during sexual intercourses, hemorrhage during traumatic sex), genital excision and social power, women are more vulnerable than men to HBV infection.

There are few epidemiological studies regarding to the prevalence of HCV in Burkina Faso. In general, this prevalence is globally low and varies according to the time of study and the kind of study population. For example HCV prevalence was 3.3% among pregnant women in 2002 (Ilboudo et al., 2010) and was 2.1% in the same center in 2009 (Zeba et al., 2011). Among blood donors, this prevalence reached 7% (Nagalo et al., 2011). In this study, 3.9% of screened people had antibodies against HCV. In Burkina Faso, HBV and HCV infections are frequently due to some practices such as women excision, ethnic scarifications and domestic use of objects contaminated with infected blood, so coinfection with HCV and HBV is common. The coinfection (HBV-HCV) rate in the present study was 2.2% and was lower than that reported by Simpore et al. (2006) (3.9%) among HIV positive women. This difference supports the idea that HBV and HCV are more prevalent in people infected by HIV (Muhammad et al., 2011). Now it is well known that coinfection of HBV with HCV can induce liver inflammation (Liu and Hou, 2006) with onset of fibrosis progressing to cirrhosis and its complications: liver cancer, gastrointestinal bleeding and in the end, severe hepatic dysfunction requiring transplantation.

CONCLUSION

Hepatitis B and C are serious health problems with severe consequences and this study showed a high prevalence of HBV and HCV markers. This high prevalence reflects the absence of health policy for fighting against these diseases. So, some measures must be taken to control their spreading. On one hand, for hepatitis B vaccination is essential for the uninfected peoples and on the other hand, the prevention is the best way to protect populations against hepatitis in the world.

ACKNOWLEDGMENTS

The authors are grateful to the staff of Saint Camille laboratory, Ouagadougou. They are deeply grateful to the Italian Episcopal Conference (C.E.I.), to UEMOA, to the RADIM House, Roma, Italy and to Doctor Luigi SPARANO for the financial support.

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