View clinical trials related to Zika.
Filter by:This phase 1 clinical trial consists of an initial open-label sentinel run-in (n=25) and a randomized, double-blind, dose-finding (n=125) investigating three antigen dose levels (low, medium and high) of VLA1601 and bedside mixing of the low-dose formulation with one of the two additional adjuvants (CpG1018®, 3M-052-AF/AP 60-702). VLA1601 will be administered according to a two-dose regimen (i.e., on Day 1 and Day 29). The primary objective of this trial is to assess the safety and tolerability of the vaccine candidate up to 7 days after each vaccination; and to assess the immune response induced by the vaccine candidate 28 days after the second vaccination. Additionally, safety and immune response of the vaccine candidate will be monitored throughout the trial.
The Pacific region is facing several emerging and neglected diseases notably mosquito-borne diseases as malaria or arboviroses among which dengue, Ross River, chikungunya and Zika. These diseases are an important cause of illness and death in the Pacific and the occurrence of arboviruses has increased in the recent years. In humans, these mosquito-borne diseases often have very similar clinical presentations (an acute febrile syndrome often self-limiting). However, these infections can progress to severe and fatal prognosis. Numerous arboviroses outbreaks and in particular dengue outbreaks have affected Vanuatu for decades. Except for DENV and Zika for which epidemiological and virological data are available for Vanuatu, the knowledge on chikungunya and Ross River circulation is very limited and needs to be defined as both viruses have intensively circulated in the region in the past. Knowledge of the level of immune protection of the population for these mosquito-borne diseases is incomplete. For this purpose, seroprevalence studies that intend to retrospectively look for antibodies (IgG) as an evidence of previous infections by a specific pathogen would be highly informative. Knowing the serological profile of the Vanuatu population for dengue and other arboviruses as Ross River, chikungunya and Zika that could have affected the country in the past would be useful in defining the population likely to be infected by future epidemics. COVID-19 pandemic caused by SARS-CoV-2 as caused over 520 million cases since December 2019. Vanuatu has been relatively spared from the pandemic due to the establishment of a sanitary sas involving strict border control. On 04 March 2022, an active COVID-19 case was confirmed at Vila Central Hospital who had no travel history, indicating transmission at community level. Overall, a total of 8487 confirmed cases have been reported since the beginning of 2022. Local vaccination campaign was initiated in July 2021. A seroprevalence study documenting population immunity to COVID-19 will inform of the breadth of COVID-19 epidemic in Vanuatu, contributing to the evaluation of undetected infections rate. This identification of vulnerable populations will inform local public Health strategies, including targeted vaccination campaigns.
Arboviruses, diseases transmitted to humans by the bite of an insect vector, are a major public health problem, particularly in tropical and sub-tropical countries. In New Caledonia, dengue epidemics are recurrent and may be associated with the co-circulation of other arboviruses such as Zika or chikungunya. The virological determinants which condition the occurrence of these epidemics may be linked to an increased vectorial competence of the vector mosquito Aedes aegypti for a particular viral isolate. In fact, the Aedes aegypti mosquito is infected by making a blood meal on a person infected with an arbovirus. The virus infects its digestive tract, then spreads throughout the mosquito's body until it reaches its salivary glands. The virus is then present in the saliva and will be injected into the human host during a new blood meal. Some viral variants are best transmitted by Aedes aegypti. In general, the study of this vectorial competence is carried out by experiments in the laboratory during which an artificial blood meal composed of mammalian blood (human, rabbit, etc.) is mixed with a viral stock. Carrying out deported blood meals during which blood collected from patients infected with an arbovirus is used to gorge mosquitoes makes it possible to place oneself in experimental conditions as close as possible to the natural cycle of transmission of arboviruses. In the human host, cells of the myeloid lineage present in the peripheral blood constitute preferred targets of replication for arboviruses. At the same time, the peripheral blood cells of patients are activated in response to infection and secrete many soluble factors released into the blood of patients. The study of blood samples from patients infected with arboviruses is therefore of prime importance for understanding both the replicative mechanisms of arboviruses but also the immune response they induce.
Arboviruses, diseases transmitted to humans by the bite of an insect vector, are a major public health problem, especially in tropical and sub-tropical countries. A promising strategy aimed at blocking the circulation of arboviruses is to release Aedes aegypti mosquitoes carrying the endosymbiotic bacterium Wolbachia. In 2019, the Wolbachia strategy was implemented in Nouméa as part of the World Mosquito Program. This intervention will modify the epidemiological profile of arboviruses in New Caledonia. Epidemiological surveillance of arboviruses requires molecular characterization of the virus contained in the serum obtained from the blood collected from patients. This molecular characterization by RNA isolation techniques, RT-qPCR monitoring and sequencing allows the construction of phylogenetic trees. In the context of the implementation of the World Mosquito Program in Nouméa, the investigators plan to follow the molecular evolution of arboviruses, over the period preceding the releases of mosquitoes carrying Wolbachia (from 1995 to 2019) then over a period of 5 years. following the releases. At the same time, the virus can be isolated by cell culture techniques and in vitro infections, allowing its study in vitro in cells or in vivo in mosquitoes. This study allows us to measure the impact of the Wolbachia strategy on the evolution of the virus's ability to replicate in cells in the presence of Wolbachia and to be transmitted by the mosquito.
Background: - The Laboratory of Infectious Diseases (LID) Clinical Studies Unit (CSU) enrolls healthy volunteers into clinical studies to study infectious diseases. - Viruses can be highly infectious and contagious. They cause considerable illness in the United States each year and a good example of this is influenza (the flu). The LID CSU performs clinical studies to learn about these viral infections and assist in the development of vaccines and treatments for the infections. These clinical studies include influenza "challenge studies" as well as natural history studies and phase I trials involving vaccines for viruses carried by mosquitos such as Zika or Dengue virus. - In influenza challenge studies studies, doctors expose a person to a flu virus. Then they study the flu through the body's natural healing process. This information will help to find better ways to prevent the flu and may also improve treatments for the flu. - Natural history studies and phase I trials of new vaccines are performed so the researchers can learn how some viral infections occur and if new vaccines are safe and potentially effective in preventing the infections. In some of these studies, participants experience insect bites with special clean (non-infected) insects (such as mosquitos) to better understand the role of insects in these infections. Objectives: - To screen healthy volunteers for future CSU studies. Eligibility: - Healthy people between the ages of 18 and 65 Design: - The 3- to 5-hour screening exam includes the following: - Medical history and physical exam - Standard blood tests including pregnancy, Hepatitis B and C, and HIV tests - Standard urine drug testing - Electrocardiogram (ECG) to test heart rhythm and function - Chest x-ray - Eligible volunteers are enrolled in the study for up to 1 year, until they take part in a CSU study or are found to be ineligible to participate. - Volunteers may withdraw from the study pool at any time.