Research Roundup: Virus mapping, Zika complications, and antibiotic development
In this regular feature on Breakthroughs, we highlight some of the most interesting reads in global health research from the past week.
Earlier this year, the World Health Organization released a list of the eight pathogens most likely to cause the next pandemic. All eight are caused by viruses, and all eight are zoonotic—originating in animals. To experts, this came as no surprise: viruses are able to rapidly evolve to infect different species or become more virulent, and nearly three-fourths of new and emerging diseases are zoonotic. Now, researchers are proposing the Global Virome Project, an initiative to characterize every virus in the world (well, 99 percent of them). Tracking down the estimated 1.3 million viruses in the world would cost nearly US$3.4 billion, however, proponents of the project argue that it would unearth insights into viruses en masse and ensure a basic scientific understanding of potential pandemic threats.
New research suggests that nearly half of women infected with Zika during pregnancy will have adverse pregnancy outcomes, including miscarriages and birth defects. The study, which enrolled 125 women in Rio de Janeiro, Brazil, is the first to quantify the frequency of these complications among pregnant women who test positive for the virus. Overall, 46 percent of women experienced significant adverse outcomes, however, the true impact may be even higher. The study only followed infants for the first three months of life, but emerging research indicates that neurological and physical defects may develop throughout the first year of life. Further, the study reveals that risk is greatest for women who are infected during the first trimester (55 percent), though adverse outcomes remain common among women infected during the second (51 percent) and third (29 percent) trimester.
Antibiotics and immune cells can only target bacteria when they are growing and dividing. Consequently, bacteria often become inactive to evade detection. Many bacteria rely on a toxin antitoxin system to achieve this. A pernicious environmental factor will prompt the bacteria to produce a toxin that puts themselves to sleep, and the abatement of that factor triggers the release of an antitoxin to wake the bacteria back up. Now, an international team of researchers has discovered that the toxin antitoxin system for E. coli, and potentially other bacteria, relies on oxygen to wake up the bacteria. When E. coli cells are dormant, both the antitoxin and oxygen must be present to destroy the original toxin. These findings suggest that oxygen could be the key to developing antibiotics that can wake up and consequently attack dormant bacteria.