An oppressive and dangerous heat wave has settled over the Mid-Shore, bringing temperatures into the high 90s /low 100s and pushing the heat index even higher. While many people simply think of it as uncomfortable, Dr. Casey Scott, health officer for the Dorchester County Health Department, says extreme heat can quickly become a serious health issue, particularly for older adults and people with chronic medical conditions.
“The amount of heat that we keep in our body is determined by a couple of things,” said Dr. Casey Scott: “one, how effectively can we get rid of that excess heat due to our bodily processes? Two, do we have any sort of barrier to heat loss or gain from the clothing we’re wearing? And then three, any extra heat that we gain from the environment.”
“When our body is unable to regulate our internal temperature and get rid of that extra heat gain, it increases our risk of heat-related conditions, such as heat exhaustion and heat stroke, which are on a spectrum,” she said. “The thing that’s important to remember, though, is that any time we’re putting these strains on our body, it stresses our vital organs, our heart and our kidneys, because they’re trying to move blood around and cool our skin.”
Those effects extend well beyond heat exhaustion.
“As a result, when we see heat extremes, it can actually worsen our health risk from chronic conditions like cardiovascular, mental, respiratory and even diabetes,” Scott said. “If you have a chronic condition, you’re going to have more risk of these poor outcomes in extremes of heat.”
She noted that heat-related mortality among people over 65 has increased dramatically over the past two decades, making prevention especially important during periods of prolonged heat.
“Our circulatory system ages as we age,” Scott said. “So our heart and our blood vessels are less able to effectively shunt the blood away from the areas that we need it to when we’re trying to cool our body down, so that’s why age really does play a role here.”
For people who spend their days outdoors, Scott said the body can adapt to heat, but only if the exposure is gradual.
“There is some physiology to that, and it’s called acclimatization,” she said. “That is our body’s adaptation to repeated exposure to heat, and it can be that you sweat more effectively, you stabilize your circulation better, you find that you’re able to perform work in extreme heat, whereas previously, before you were acclimatized, you might not be able to.”
The process is familiar to employers whose workers spend long hours outside.
“We know about this in the workplace, because there are folks who, due to their jobs, must work outside,” Scott said. “There are guidelines for how we introduce someone, if you will, to this extreme heat environment, so that they don’t end up with symptoms of heat exhaustion or heat stroke.”
For someone new to working in extreme heat, she said the recommendation is no more than 20 percent exposure on the first day, with an additional 20 percent each day afterward. Workers who are already acclimatized usually regain that tolerance within two or three days after time away.
“It is easier to go through this process if you are more physically fit and if you are younger,” she said.
Monitoring the effects of extreme heat has become an important part of the Health Department’s emergency preparedness efforts, which include conducting surveillance and watching for patterns such as increased disease transmission or weather-related hospitalizations.
Heat illness can develop gradually, beginning with symptoms that many people overlook.
These can include mild dehydration, heat rash, and muscle cramps, and can be prevented by drinking plenty of water, taking breaks, and pairing water with electrolytes you may lose through sweat. Scott recommends paying attention to electrolyte replacement while avoiding sugary drinks.
At the other end of the spectrum is heat stroke, which requires immediate medical treatment.
Scott advises looking for signs such as disorientation, rapid pulse, and shallow breathing, which can indicate that vital organs are starting to fail.
She said older adults, infants and people with underlying medical conditions are particularly vulnerable because they are less able to regulate their internal body temperature.
Scott said avoiding those emergencies begins with simple precautions.
“Staying out of the heat, being in air conditioning, if possible, avoiding going outside, especially avoiding strenuous activity during the hottest time of day,” she said. “If you must be outside, find shade, and remember that perceived temperatures in the sun can be higher than what you’re seeing on your thermostat.”
Humidity makes those conditions even more dangerous, particularly if humidity is also high. “Sweat is less effective the more humid it is.”
She also recommends wearing light, loose-fitting clothing, cooling off with showers or wet towels, and increasing water intake throughout the day.
“We want to make sure that you’re recognizing that when you’re in the heat, you do need to hydrate more than you normally would,” Scott said. “Increased fatigue, dizziness, lightheadedness, just feeling run down. If you find that you’re not sweating in a situation where you typically would sweat, perhaps you’re dehydrated, or your body’s not able to regulate the temperature as well as it could.”
Helping residents stay safe is another function of the Dorchester County Health Department.
“We coordinate a community effort where there are daytime cooling centers, not usually at the health department, but our employees can help you locate them,” she said. “We also help distribute extreme weather packs, cooling blankets, and extra water, so if you are in need, or you know someone in need.”
She encourages local business owners interested in temporarily offering their cooled spaces to those in need to contact the health department, as more accessible cooling centers can save lives.
Scott also hopes residents will remember that looking after others is just as important as protecting themselves.
“Keep an eye on your elderly neighbors,” she said. “And if you have outside pets, if you can bring them in, make sure they have plenty of water and shade. If you must be outside, scope out where there might be shade, trees, or public spaces where you can rest from the heat, if necessary.”
Residents who need assistance locating cooling centers or other heat-related resources should visit www.dorchesterhealth.org or call 410-228-3223.
This audio is approximately 9 minutes long.
Shore Stories with Val Cavalheri is a co-production of the Spy and Chesapeake Public Radio
