President Obama said on Wednesday that he's "cautiously more optimistic" about the Ebola situation in the United States, now that we know no one else who had initial contact with Thomas Eric Duncan, the Liberian man who died of Ebola, has contracted the disease. Sadly, there aren't many reasons to be optimistic about the outbreak in West Africa. The official death toll is now 4,877, but the World Health Organization says the real number is probably much higher. As Reuters reports, Ebola cases are believed to be underreported "by a factor of 1.5 in Guinea, 2 in Sierra Leone and 2.5 in Liberia, while the death rate is thought to be about 70 percent of all cases." That means it's likely that about 15,000 people have already died.