The vast majority of infectious diseases are caused by microorganisms, called "microbes." However, only about 1% of microbes cause disease! We call these microbes who cause disease, pathogens.
You are probably familiar with many of these pathogens. Let's look at the ones we saw in the phenomenon video first. Read the following and then answer the questions below.
White Nose Syndrome:
White-nose syndrome (WNS) is a disease that affects hibernating bats and is caused by a fungus, Pseudogymnoascus destructans, or Pd for short. Sometimes Pd looks like a white fuzz on bats’ faces, which is how the disease got its name. Pd grows in cold, dark and damp places. It attacks the bare skin of bats while they’re hibernating in a relatively inactive state. As it grows, Pd causes changes in bats that make them become active more than usual and burn up fat they need to survive the winter. Bats with white-nose syndrome may do strange things like fly outside in the daytime in the winter.
Fire blight on apple tree:
Fire blight is a common and very destructive bacterial disease of apples and pears. The disease is caused by the bacterium Erwinia amylovora. On apples and pears, the disease can kill blossoms, fruit, shoots, twigs, branches and entire trees. While young trees can be killed in a single season, older trees can survive several years, even with continuous dieback.
Brain worm in Moose:
Brain worm is the term commonly applied to the parasitic nematode (round worm), Parelaphostrongylus tenuis (P. tenuis). White-tailed deer are the normal host for this parasite. Most of the time, they are not affected by the parasite. However, other species such as moose, mule deer, reindeer/caribou, sheep, goats, alpacas, and llamas are abnormal hosts and can develop disease or die if infected.
Sea Star Wasting Syndrome: (SSWS/SSWD)
In December 2020, sunflower sea stars were placed on the ICUN's red list of threatened species. There has been a 90% decline in this species due to warming oceans an an epidemic called "Sea Star Wasting Syndrome." Scientists from The Nature Conservancy and Oregon State University, who led the listing effort, estimate that 90.6% of the sunflower sea star population is now lost from the outbreak, with as many as 5.75 billion dead from the disease. Symptoms of the disease include a deflated appearance, white lesions and twisted arms, followed by softening tissue, loss of arms, and death. The disease progresses rapidly, often killing its victims within a matter of days. In an effort to identify the potential pathogen and conditions responsible for SSWD, scientists and their partners collected extensive survey data and tissue samples, but the cause remains a mystery that several research institutions are working hard to unlock.
