The age at first exposure to HBV plays a very important role in the evolution of infection. the EUVAX B? vaccine respectively at birth, two months and four months of life. Seven months after delivery, venous blood samples were collected from mothers and their children. Antibodies against hepatitis B surface antigen (AbHBs) were measured in vaccinated children using the ELISA Kit DNA extraction was performed on samples from HBV-seropositive mothers and their children using the Kit and for Real Time PCR, the Kit was used. Serological diagnosis in pregnant women revealed 22 (9.28%) hepatitis B surface antigen (HBsAg) positive samples of which 21 were positive for viral DNA by real-time PCR. Among the 22 HBsAg+ women, five (05) transmitted the computer virus to their children with a vertical transmission rate of 22.73%. A transmission rate of 23.81% (5/21) was found with the PCR method. Analysis of AbHBs levels revealed that 98.31% of the children had an average concentration of 218.07 74.66 IU/L, which is well above the minimum threshold for protection (11 IU/L). This study has confirmed that vertical transmission of HBV is usually a reality in Burkina GNE-207 Faso and that vaccination at birth would significantly reduce this transmission. strong class=”kwd-title” Key words: Viral Hepatitis B, HBsAg, Real- Time PCR, Vertical Transmission, Vaccination Introduction Currently, the World Health Organization (WHO) estimates that 257 million people live with hepatitis B computer virus (HBV) infection worldwide.1 HBV is responsible for more than 686,000 deaths per year and this infection is considered as the second most common cause of cancer deaths after tobacco.1 Africa is the most affected region of the world with approximately 150 million cases of chronic hepatitis B and C associated with the risk of developing cirrhosis or liver malignancy.2 Burkina Faso (BF) which is a HBV high endemic area according to WHO classification has prevalence well above 8%.3-6 A study carried out at the University or college Hospital Yalgado Ouedraogo of Ouagadougou (CHU-YO) showed a prevalence of 4.1% in newborns to HBV infected mothers with a vertical transmission rate of 37.1%.7Another study conducted in 2002 at the Saint Camille Hospital of Ouagadougou found a vertical transmission rate of 25.0%.8 Thus, according to McMahon et em al. /em 9 vertical transmission remains the most important mechanism of HBV chronic infections in Africa. The age at first exposure to HBV plays a very important role in the development of infection. Children born to mothers with active hepatitis B, who are positive for HBV e antigen (HBeAg+), GNE-207 are at CTLA1 high risk of contamination at birth or during early child years and of becoming chronic service providers.10 Moreover, the infection could occur during childhood and would imply transmission though breastfeeding. In addition, since the hepatitis B computer virus can be transmitted by blood, saliva and other fluids of the infected human organism, infected parents could transmit the computer virus to their infants and children as they take care of them including some traditional methods of caring for place bites by applying saliva to site sites. If the latter transmission route plays a key role in HBV contamination, then the local density of these blood-sucking arthropods would be a relevant factor to take into account during consciousness against hepatitis B contamination.3 Following this infection, approximately 25% of these children are at greater risk of death because they may develop hepatocellular carcinoma or cirrhosis in adulthood.9 The low rate of screening for HBV in pregnant women is therefore a high risk factor for vertical transmission. Hence, the prevention of mother-to-child transmission of HBV plays a key role in the reduction of the disease prevalence. In many African countries, there is no active program to prevent mother-to-child transmission (PMTCT) of HBV. For a number of years, to prevent hepatitis B computer virus infection in children, the Ministry of Health of Burkina Faso, through the Expanded GNE-207 Program of Immunization (EPI), advocated the vaccine against HBV for all those children at eight weeks.