Vaccination Strategies against Highly Pathogenic Arenaviruses: The Next Steps toward Clinical Trials.

Vaccination is one of the most valuable weapons against infectious diseases and has led to a significant reduction in mortality and morbidity. However, for most viral hemorrhagic fevers caused by arenaviruses, no prophylactic vaccine is available. This is particularly problematic as these diseases are notoriously difficult to diagnose and treat. Lassa fever is globally the most important of the fevers caused by arenaviruses, potentially affecting millions of people living in endemic areas, particularly in Nigeria. Annually, an estimated 300,000 humans are infected and several thousands succumb to the disease. The successful development of the vaccine "Candid#1" against Junin virus, the causative agent of Argentine hemorrhagic fever, proved that an effective arenavirus vaccine can be developed. Although several promising studies toward the development of a Lassa fever vaccine have been published, no vaccine candidate has been tested in human volunteers or patients. This review summarizes the immunology and other aspects of existing experimental arenavirus vaccine studies, discusses the reasons for the lack of a vaccine, and proposes a plan for overcoming the final hurdles toward clinical trials

Störungen des Betriebs geothermischer Anlagen durch mikrobielle Stoffwechselprozesse und Erfolg von Gegenmaßnahmen

In the context of geothermal systems, biofilms can influence mineral formation and material resistance against corrosion. In three geothermal plants with different salinity and temperature, organisms of the sulfur cycle have contributed to process failures. On the cold side of a heat store, the increased diversity and abundance of sulfate reducing bacteria (SRB) revealed their participation in corrosion processes and their contribution to a decline in injection efficiency. In all plants, a temporary ingress of oxygen or nitrate led to an increased abundance of sulfur oxidizing bacteria (SOB) that might have accelerated corrosion. In addition, the increase in SOB abundance led to filter clogging in a cold store. Based on their role in microbial-induced corrosion (MIC), changes in the abundance of SOB and SRB may indicate the cause of failure. Measures to control microbial growth, mineral deposits and corrosion, such as temporary increases in temperature, acidification, and addition of hydrogen peroxide (H_2O_2) and nitrate, were evaluated.In geothermischen Anlagen können Biofilme die Mineralbildung und die Injektivität von Bohrungen sowie die Materialbeständigkeit beeinträchtigen. In drei bezüglich Temperatur und Salinität sehr unterschiedlichen Anlagen waren Organismen des Schwefelkreislaufs an Betriebsstörungen beteiligt: Die erhöhte Abundanz von Sulfat-reduzierenden Bakterien (SRB) auf der kalten Seite eines Wärmespeichers wies auf deren Beteiligung an der Korrosion und der Abnahme der Injektivität hin. In allen Anlagen führte der Zutritt von Sauerstoff bzw. der Eintrag von Nitrat zu einer temporären Zunahme Schwefel-oxidierender Bakterien (SOB) und hat vermutlich Korrosionsprozesse beschleunigt. Außerdem hatte in einem Kältespeicher die temporäre Zunahme der SOB ein Filterclogging zur Folge. Aufgrund ihrer entscheidenden Rolle bei mikrobiell induzierter Korrosion (MIC) weisen Änderungen in der Abundanz von SOB und SRB auf die Ursachen mikrobiell bedingter Störungen hin. Zur Beseitigung der Störungen wurden temporäre Erhöhungen der Temperatur, Säuerungen sowie die Zugabe von Wasserstoffperoxid (H2O2) oder Nitrat in den Anlagen getestet und aus mikrobiologischer Sicht bewertet