“Perhaps one of the most startling facts is that we truly have climate refugees within the United States,” Salas said in a conference call before the brief’s release. “I think that this is something that a lot of individuals within the U.S. think is a distant effect, but it’s truly something that we’re seeing here today. In fact, earlier this year I had a patient who came from Puerto Rico. She was elderly, she showed up with her luggage, and truly had a bag with medications that she hadn’t taken in a few weeks … She was truly a climate refugee.” And, as Salas notes, the most vulnerable populations to a whole range of health problems are those that have been recently displaced. As has emerged recently in studies of disaster-affected communities, they also suffer post-traumatic stress and a uniquely high mental-health burden that can persist for years.
It’s no wonder that displacement and the long-term effects of disasters are also wrapped up with spikes in diseases carried by mosquitoes, ticks, and fleas, and those transmitted by pathogens in warm water. In tropical Puerto Rico, Zika outbreaks before the storm led to fears of even greater outbreaks after the storm. But on the more temperate mainland, the real risk is the spread of subtropical diseases to places where temperatures were once too cold to support the diseases. The Lancet’s report cites another from the Centers for Disease Control and Prevention that shows that disease cases from mosquitoes, ticks, and fleas more than tripled from just under 30,000 to almost 100,000 a year from 2004 to 2016, and also highlights a steady increase in the viability of vibrio, a bacteria found in warm waters that can cause life-threatening infections of gastroenteritis.
According to Gina McCarthy, the director of the Center for Climate, Health, and the Global Environment and a former administrator of the Environmental Protection Agency under President Barack Obama, the increased geographic spread of these diseases can reverse the signature gains of the past century of American health policy—namely, the near-eradication of many of the communicable infectious fever diseases that have always haunted humanity. “You’re seeing challenges as broad as Massachusetts, where you’re seeing that West Nile virus is increasing,” she said on the conference call, “or Lyme disease, because of species of mosquito that are spreading diseases that we weren’t familiar with years ago, that are now becoming commonplace.”
In a forum by the American Public Health Association (APHA) and the Harvard Global Health Institute discussing The Lancet’s global report and its brief for the United States, the authors and several public-health experts stressed to me that these findings were only the tip of the iceberg of some truly unforeseen future effects, that they were only examples of larger global trends, and that they don’t reflect far-off future scenarios but rather what is currently observable in existing climate change.