Both Lewis and secretor status mediate susceptibility to rotavirus infections in a rotavirus genotype-dependent manner.

BACKGROUND: The live oral rotavirus (RV) vaccines have shown a reduced efficacy in Africa. Recent in vitro studies have shown binding of the RV surface protein (VP4) to histo-blood group antigens (HBGAs) in an RV genotype-dependent manner, suggesting them to be putative receptors for RV. The diversity of HBGA phenotypes in different ethnic populations, combined with prevalence/absence of specific RV genotypes, led us to hypothesize whether the genetic variations in HBGAs in a population limit susceptibility to certain RV genotypes, plausibly leading to reduced vaccine efficacy. METHODS: Association between HBGAs status and susceptibility to RV P genotypes was investigated in children in Burkina Faso and Nicaragua. In total, 242 children with diarrhea in Burkina Faso and Nicaragua were investigated, 93 of whom were RV positive. RESULTS: In Burkina Faso, the P[8] RV strains (n = 27) infected only Lewis- and secretor-positive children (27/27; P < .0001), but no Lewis-negative children. In contrast, the P[6] strains (n = 27) infected predominantly Lewis-negative children (n = 18; P < .0001) but also Lewis-positive children, irrespective of their secretor status. The results from Nicaragua confirmed that all P[8]-infected children (n = 22) were secretor Lewis positive. CONCLUSIONS: As VP4 of genotype P[8] is a component of current RV vaccines, our finding that Lewis-negative children are resistant to P[8] strains provides a plausible explanation for the reduced vaccine efficacy in populations with a high percentage of Lewis-negative individuals, such as in Africa. Furthermore, our findings provide a plausible explanation as to why P[6] RV strains are more common in Africa.

Towards the complete eradication of mother-to-child HIV/HBV coinfection at Saint Camille Medical Centre in Burkina Faso, Africa.

The coinfection of HIV and hepatitis B virus (HBV) and their vertical transmission constitute a public health problem in sub-Saharan countries of Africa. The objectives of this research are: i) identify the pregnant women that are coinfected by HIV and HBV at Saint Camille Medical Centre; ii) use three antiretroviral drugs (zidovudine, nevirapine and lamivudine) to interrupt the vertical transmission of HIV and HBV from infected mothers; and iii) use the PCR technique to diagnose children who are vertically infected by these viruses in order to offer them an early medical assistance. At Saint Camille Medical Centre, 115 pregnant women, aged from 19 to 41 years, were diagnosed as HIV-positive and, among them, 14 coinfected with HBV. They had at least 32 weeks of amenorrhoea and all of them received the HAART, which contained lamivudine. Two to six months after childbirth, the babies underwent PCR diagnosis for HIV and HBV. The results revealed that, among these mothers, 64.4% were housewives, 36.5% were illiterates, and only 1.7% had a university degree. The rate of vertical transmission of HIV and HBV was 0.0% (0/115) and 21.4% (3/14), respectively. The 3 mothers who transmitted the HBV to their children had all HBsAg, HbeAg, and HBV DNA positive. An antiretroviral therapy that in addition to zidovudine and nevirapine includes lamivudine could, as in the present study, block or reduce the vertical transmission in HIV positive pregnant women who are coinfected with HBV.

Towards the complete eradication of mother-to-child HIV/HBV coinfection at Saint Camille Medical Centre in Burkina Faso, Africa

The coinfection of HIV and hepatitis B virus (HBV) and their vertical transmission constitute a public health problem in sub-Saharan countries of Africa. The objectives of this research are: i) identify the pregnant women that are coinfected by HIV and HBV at Saint Camille Medical Centre; ii) use three antiretroviral drugs (zidovudine, nevirapine and lamivudine) to interrupt the vertical transmission of HIV and HBV from infected mothers; and iii) use the PCR technique to diagnose children who are vertically infected by these viruses in order to offer them an early medical assistance. At Saint Camille Medical Centre, 115 pregnant women, aged from 19 to 41 years, were diagnosed as HIV-positive and, among them, 14 coinfected with HBV. They had at least 32 weeks of amenorrhoea and all of them received the HAART, which contained lamivudine. Two to six months after childbirth, the babies underwent PCR diagnosis for HIV and HBV. The results revealed that, among these mothers, 64.4 percent were housewives, 36.5 percent were illiterates, and only 1.7 percent had a university degree. The rate of vertical transmission of HIV and HBV was 0.0 percent (0/115) and 21.4 percent (3/14), respectively. The 3 mothers who transmitted the HBV to their children had all HBsAg, HbeAg, and HBV DNA positive. An antiretroviral therapy that in addition to zidovudine and nevirapine includes lamivudine could, as in the present study, block or reduce the vertical transmission in HIV positive pregnant women who are coinfected with HBV.