It is estimated that over 2.5 billion people are at risk for contracting dengue, a virus responsible for 50-390 million infections in addition to thousands of hospitalizations and deaths each year. There are no licensed vaccines available to combat this pathogen but substantial efforts are underway to develop live-attenuated, inactivated, and subunit vaccines that will protect against each of t...

In TB, prophylactic immunization plays a key preventive strategy. A live attenuated vaccine called bacille CalmetteGuérin (BCG) was developed way back in 1906 by Albert Calmette and Camille Guérin. The BCG vaccine was derived from an attenuated strain of Mycobacterium bovis and first used on humans in 1921 in France [2]. Currently the vaccine is given to neonates and children as a part of unive...

The development of a new tuberculosis vaccine is an urgent need due to the failure of the current vaccine, BCG, to protect against the respiratory form of the disease. MTBVAC is an attenuated Mycobacterium tuberculosis vaccine candidate genetically engineered to fulfil the Geneva consensus requirements to enter human clinical trials. We selected a M. tuberculosis clinical isolate to generate tw...

We demonstrate that Mycobacterium tuberculosis that is unable to export the complex lipid phthiocerol dimycocerosate has a decreased capacity to replicate in mice and affords sustained protective immunity against M. tuberculosis infection Protection was significantly better than that provided by the existing vaccine, Mycobacterium bovis bacille Calmette-Guérin (BCG), and this improved protectiv...

Tuberculosis is still one of the main challenges to human global health, leading to about two million deaths every year. One of the reasons for its success is the lack of efficacy of the widely used vaccine Mycobacterium bovis BCG. In this article, we analyze the potential use of an attenuated mutant of Mycobacterium tuberculosis H37Rv lacking the sigma factor sigma(E) as a live vaccine. We hav...

An attenuated strain of Flavobacterium psychrophilum (CSF259-93B.17) has shown potential as a vaccine for prevention of bacterial coldwater disease (BCWD) in rainbow trout, Oncorhynchus mykiss (Walbaum). Because BCWD outbreaks can result in high mortality in other salmonid species, specifically coho salmon, Oncorhynchus kisutch (Walbaum), the live-attenuated strain was tested as a vaccine in th...

As the impact of dengue expands, a safe and effective vaccine will benefit the world greatly. Recent progress and novel approaches have advanced the field, but many challenges and unanswered questions remain for dengue vaccine developers. The most advanced dengue vaccine candidate, a chimeric yellow fever dengue (CYD) tetravalent vaccine, was the first dengue vaccine tested in a field efficacy ...

DNA vaccines, the third-generation vaccines, were extensively studied. The attenuated Salmonella choleraesuis (S. choleraesuis) was widely focused as a carrier to deliver DNA vaccines in the chromosome-plasmid balanced-lethal system. The efficacy of inhibin DNA vaccine delivered by attenuated S. choleraesuis was proved in mice and cows in our previous studies. In this study, the efficacy of inh...

Many live virus vaccines derived by empirical routes exhibit temperature-sensitive (ts) phenotypes. The live virus vaccines that have been outstandingly successful in controlling poliomyelitis are the prime example of this phenomenon. The three live attenuated strains developed by Sabin were derived from wild-type isolates by rapid sequential passage at high multiplicity of infection in monkey ...

An intranasal vaccine vector would elicit protective immunity at the respiratory mucosa, the portal of entry and the primary site for replication for measles virus (MV) and other respiratory viruses. In a murine model of pulmonary Shigella, we demonstrate here that a candidate-attenuated Shigella vaccine vector is safely tolerated in IFN-gamma deficient mice at an inoculum that is 1 million-fol...