A late June heat wave led to skyrocketing emergency room visits and seven heat-related deaths in a single week, boosting the total number of heat-related deaths this year to nine, according to the latest state report.

The data from the Maryland Department of Health showed that 472 people had to go to urgent care or the emergency room for heat-related illnesses from June 22 through June 28, a week in which the National Weather Service said parts of Maryland would see a heat index of up to 110 degrees during the hottest parts of the day.

That’s a significant increase from the previous week, when 93 people landed in emergency departments across the state, and trends higher than previous heat-related illness data in recent years.

High temperatures that week also resulted in seven deaths, raising the total number of heat-related deaths so far this heat season to nine, with months left to go. (The latest was a six month-old Harford County girl who died Sunday after being left in a hot car for hours.)

• This story was first published by Maryland Matters.

State health officials and county emergency workers are warning residents to take caution in similar conditions in the days ahead.

“We are very saddened to report these heat-related deaths in Maryland,” David McCallister, a communications official with the health department, said in a written statement Monday. “As we experience more hot days this summer, these tragedies remind us to take the necessary steps to avoid overheating.

“Be sure to always check on family, friends, and neighbors who may be particularly vulnerable to heat, including young children, senior citizens and people with chronic diseases,” his statement said.

Signs of heat-related illness include heavy sweating, dizziness, fatigue, weakness, rapid pulse, low blood pressure upon standing, muscle cramps, moist skin with goose bumps when in the heat, nausea and headache.

Most Vulnerable Groups

The data is part of weekly reporting on heat-related illnesses during the annual heat season, which runs roughly from the end of April through September.

“Demographic patterns remain consistent with previous years: Emergency Department visits are highest among males (63%), individuals aged 18-44 (43%), and white individuals (53%),” McCallister’s statement said.

“Of the eight deaths reported so far, 88% were among males and 63% were among white individuals. Most notably, 75% of deaths occurred in individuals aged 65 and older.”

He said that there have been a total of 729 recorded heat-related emergency department visits so far,” making up over 60% of the total number of visits reported during the entire 2024 heat season.”

“It is also important to note that 65% of visits have occurred in Health Regions 3 and 5, which encompass the Baltimore City area and the National Capital Region,” he said.

Danielle Knatz, bureau chief for the Baltimore County Fire Department’s Emergency Medical Services, said the heat wave during the last week of June led to a greater demand in emergency response services.

“We did see a slight increase in our heat-related responses, and most of them appear to be incidents that occurred outside of the home. So parking lots, restaurants, streets, highways – likely people working outside,” Knatz said. “A couple related to swimming pools or water, but not too many.”

She said that most of the emergency room visits in Baltimore County were connected to heat exhaustion from physical activity, though other people who ended up in Baltimore County emergency rooms faced different challenges.

“We had several that were elderly. Elderly and younger patients don’t respond well to changes in the climate,” she said. “There could be underlying conditions that are causing those people to have difficulties, or certain medications that they’re taking. That was pretty much what we were seeing that week.”

She said the EMS agency uses the heat-related illness data to track trends across the county and help crews be prepared to the next heat wave.

“For example, for this week, we front-loaded our units with extra cold packs to be able to handle these types of incidents,” she said. “Because obviously, there are times when we want to aggressively cool patients, so we want to make sure that we have cold packs to be able to do that.

Heat and Thunderstorms

The National Weather Service issued heat advisories on Monday and Tuesday. Temperatures reached 90°F and 95°F, respectively, on those days.  Yesterday the Baltimore Health Department issued a Code Red Extreme Heat Alert because, with humidity, the heat index was expected to exceed 100°.

Under those conditions, workplaces in high temperature environments were expected to implement additional heat safety measures under new state labor regulations that launched this year. That includes more frequent and longer breaks for workers and additional cooling measures on worksites.

For today and for the next few days, Baltimore and the region are facing intermittent thunderstorms and high temperatures in the upper 80s to low 90s, the National Weather Service says. A flood watch is in effect today from 2 p.m. through the evening.

Knatz urges families to take caution for the remainder of the heat season.

“It’s important for people to just monitor the weather and be prepared,” she said. “By taking appropriate rests, by drinking plenty of fluids.”

The health department also reminds Marylanders to avoid alcohol, caffeine and overly sweetened beverages during high temperatures.

It suggests that people wear loose-fitting, lightweight and light-colored clothing along with sunscreen.

• For more information, see the State Health Department’s Extreme Heat Resource Page.