Arboviral infections,especially dengue,continue to cause significant health burden in their endemic regions.One of the strategies to tackle these infections is to replace the main vector agent,Ae.aegypti,with the ones...Arboviral infections,especially dengue,continue to cause significant health burden in their endemic regions.One of the strategies to tackle these infections is to replace the main vector agent,Ae.aegypti,with the ones incapable of transmitting the virus.Wolbachia,an intracellular bacterium,has shown promise in achieving this goal.However,key factors such as imperfect maternal transmission,loss of Wolbachia infection,reduced reproductive capacity and shortened life-span affect the dynamics of Wolbachia in different forms in the Ae.aegypti population.In this study,we developed a Wolbachia transmission dynamic model adjusting for imperfect maternal transmission and loss ofWolbachia infection.The invasive reproductive number that determines the likelihood of replacement of the Wolbachia-uninfected(WU)population is derived and with it,we established the local and global stability of the equilibrium points.This analysis clearly shows that cytoplasmic incompatibility(CI)does not guarantee establishment of the Wolbachia-infected(WI)mosquitoes as imperfect maternal transmission and loss of Wolbachia infection could outweigh the gains from CI.Optimal release programs depending on the level of imperfect maternal transmission and loss of Wolbachia infection are shown.Hence,it is left to decision makers to either aim for replacement or co-existence of both populations.展开更多
The priority of The Gambia government is to eliminate maternal to child transmission of HIV and in line with this priority, the country implemented an antiretroviral therapy (ART) program. With this, all HIV infected ...The priority of The Gambia government is to eliminate maternal to child transmission of HIV and in line with this priority, the country implemented an antiretroviral therapy (ART) program. With this, all HIV infected pregnant and breastfeeding mothers and infants have access to ARV drugs. This study aims to determine the prevalence of vertical transmission of HIV among women receiving the ARV drugs. Dried blood spot samples were collected from 109 HIV-exposed infants enrolled in 13 PMTCT sites across the country. A qualitative detection of proviral-DNA of HIV-1 was performed using the RealTime Abbott PCR assay. Data from 105 mothers were analyzed using SPSS version 16.0 and association of risk factors to PCR results were analyzed using (Crosstabs) Pearson Chi-Square. The p-value of significant was set at p < 0.05. This study has found that the prevalence of vertical transmission of HIV is 0.0% (0/64) among women that received the ARV prophylaxis then started ART, 7.1% (2/28) among mothers that received HIV prophylaxis only, and 38.4% (5/13) among women who neither receive HIV-prophylaxis nor ART during pregnancy or breastfeeding. Other risk factors of vertical transmission such as late initiation of treatment, default during treatment and first born of twins were found to be significantly associated with vertical transmission p = 0.001, p = 0.022 and p = 0.000 respectively. This study has found that the early intervention of ART at the onset of pregnancy through breastfeeding can eliminates Maternal to Child transmission of HIV-1and a high risk of vertical transmission was found among women who neither receive prophylaxis nor ART. If the effectiveness of the antiretroviral therapy is maintain, The Gambia, in the near future will attain the WHO’s goal to eliminate maternal to child transmission of HIV.展开更多
文摘Arboviral infections,especially dengue,continue to cause significant health burden in their endemic regions.One of the strategies to tackle these infections is to replace the main vector agent,Ae.aegypti,with the ones incapable of transmitting the virus.Wolbachia,an intracellular bacterium,has shown promise in achieving this goal.However,key factors such as imperfect maternal transmission,loss of Wolbachia infection,reduced reproductive capacity and shortened life-span affect the dynamics of Wolbachia in different forms in the Ae.aegypti population.In this study,we developed a Wolbachia transmission dynamic model adjusting for imperfect maternal transmission and loss ofWolbachia infection.The invasive reproductive number that determines the likelihood of replacement of the Wolbachia-uninfected(WU)population is derived and with it,we established the local and global stability of the equilibrium points.This analysis clearly shows that cytoplasmic incompatibility(CI)does not guarantee establishment of the Wolbachia-infected(WI)mosquitoes as imperfect maternal transmission and loss of Wolbachia infection could outweigh the gains from CI.Optimal release programs depending on the level of imperfect maternal transmission and loss of Wolbachia infection are shown.Hence,it is left to decision makers to either aim for replacement or co-existence of both populations.
文摘The priority of The Gambia government is to eliminate maternal to child transmission of HIV and in line with this priority, the country implemented an antiretroviral therapy (ART) program. With this, all HIV infected pregnant and breastfeeding mothers and infants have access to ARV drugs. This study aims to determine the prevalence of vertical transmission of HIV among women receiving the ARV drugs. Dried blood spot samples were collected from 109 HIV-exposed infants enrolled in 13 PMTCT sites across the country. A qualitative detection of proviral-DNA of HIV-1 was performed using the RealTime Abbott PCR assay. Data from 105 mothers were analyzed using SPSS version 16.0 and association of risk factors to PCR results were analyzed using (Crosstabs) Pearson Chi-Square. The p-value of significant was set at p < 0.05. This study has found that the prevalence of vertical transmission of HIV is 0.0% (0/64) among women that received the ARV prophylaxis then started ART, 7.1% (2/28) among mothers that received HIV prophylaxis only, and 38.4% (5/13) among women who neither receive HIV-prophylaxis nor ART during pregnancy or breastfeeding. Other risk factors of vertical transmission such as late initiation of treatment, default during treatment and first born of twins were found to be significantly associated with vertical transmission p = 0.001, p = 0.022 and p = 0.000 respectively. This study has found that the early intervention of ART at the onset of pregnancy through breastfeeding can eliminates Maternal to Child transmission of HIV-1and a high risk of vertical transmission was found among women who neither receive prophylaxis nor ART. If the effectiveness of the antiretroviral therapy is maintain, The Gambia, in the near future will attain the WHO’s goal to eliminate maternal to child transmission of HIV.
