4 Clinical Trials for Various Conditions
This is an open-label, non-randomized study. Volunteers will be vaccinated with the oral cholera vaccine, Vaxchora. Vaxchora has been licensed by the Food and Drug Administration (FDA) for travelers to developing countries. Volunteers will also be asked to provide blood specimens over a follow-up time period of up to eight years. The specimens obtained in this clinical research study will be used to further the investigator's understanding of the protective immunological mechanisms that can be elicited systemically and may be applicable to other enteric pathogens.
This is an open-label, non-randomized study. The purpose of this study is to better understand how vaccines against typhoid fever and cholera affect the normal immune system and bacteria in the intestine. Patients having standard-of-care endoscopies (colonoscopy and/or esophagogastroduodenoscopy (EGD)) will be divided into 3 groups: Group 1: Vivotif typhoid vaccination and/or Vaxchora cholera vaccination then endoscopy Group 2: Endoscopy, then Vivotif typhoid vaccination and/or Vaxchora cholera vaccination, then follow-up endoscopy Group 3: Endoscopy without vaccination. Both vaccines used in this study are licensed by the Food and Drug Administration (FDA) for travelers to developing countries. Volunteers will be asked to donate tissue, blood, saliva and stool samples for studying how the body responds to the typhoid and/or cholera vaccine.
This study, to be carried out immediately following an emergency, reactive cholera vaccination campaign in Nsanje District, Malawi, will be a cohort study to estimate the safety of killed oral cholera vaccine (OCV), in pregnant women as measured by ShancholTM, on pregnancy outcomes and birth defects. While limited evidence which suggests that the vaccine is safe in pregnant women, this setting will allow investigators to answer this question in a community where more than 100,000 people will receive vaccine with no restrictions on pregnancy status. In past cholera vaccine campaigns including clinical trials, pregnant women were excluded due to lack of safety data. However, in this campaign, the decision by the Ministry of Health is that the benefits of offering vaccine to all individuals regardless of pregnancy status far outweigh any theoretical risk. Here the investigators specifically propose to: Specific Objective 1: To conduct surveillance of pregnant women to detect adverse pregnancy outcomes within communities in Nsanje District, Malawi that received oral cholera vaccine in a reactive vaccination campaign that started on 30 March 2015. Through household surveying and enrollment of pregnant women with monthly follow-up visits, the investigators will determine the cumulative incidence of adverse pregnancy outcomes among vaccinated and unvaccinated women in Nsanje and Chikwawa Districts, Malawi. Specific Objective 2: To compare the cumulative incidence of pregnancy loss (miscarriage and stillbirth) of women who received oral cholera vaccine while they were pregnant to women who were vaccinated and became pregnant after the end of the final round of vaccination in Nsanje and Chikwawa Districts, Malawi. Specific Objective 3: To compare the incidence of newborn malformations in a cohort of infants that had fetal exposure to oral cholera vaccine compared to those without such exposure in Nsanje and Chikwawa Districts, Malawi.
The primary objective of this study is to evaluate the antibody response to the cholera vaccine, Vaxchora®, in healthy subjects. Investigators also seek to evaluate additional markers of the adaptive immune response including plasmablasts, activated B cells, memory B cells, and T cell responses in healthy subjects receiving cholera vaccine, produce monoclonal antibodies against cholera, and evaluate the safety and reactogenicity in healthy subjects receiving cholera vaccine.