Md. – The St. Mary’s County Health Department (SMCHD) encourages residents to take precautions against health concerns that become more common during the summer months, including tick-borne illness, Vibrio infection, and heat-related illness
Many residents and visitors spend more time outdoors during the summer for work, recreation, crabbing, hiking, sports, gardening, boating, and other activities. Simple prevention steps can reduce the risk of illness and help residents enjoy the season safely
“Summer is a wonderful time to be outdoors in St. Mary’s County, but it is also a time to be alert to seasonal health risks,” said Dr. Meena Brewster, St. Mary’s County Health Officer. “Residents can protect themselves and their families by preventing tick bites, protecting wounds around natural waters, avoiding raw or undercooked shellfish, and taking heat seriously.”
Ticks and Tick-Borne Illness
Ticks are common in Maryland and can carry bacteria, viruses, and parasites that may cause illness in people and animals. Tick-borne diseases remain an important public health concern in Maryland and across the United States
In St. Mary’s County, tick-borne conditions of most concern include Lyme disease, Rocky Mountain spotted fever, and alpha-gal syndrome. Lyme disease is the most commonly reported tick-borne disease in Maryland and in St. Mary’s County. In 2025, St. Mary’s County had 62 reported Lyme disease cases; however, reported case counts likely underestimate the true number of infections because not all infections are diagnosed, tested, or reported
Rocky Mountain spotted fever is reported less frequently but can be severe and requires prompt medical attention
Alpha-gal syndrome is also an ongoing local concern. Alpha-gal syndrome is an allergic condition that can develop after a tick bite, most commonly associated with the lone star tick. People with alpha-gal syndrome may have delayed allergic reactions after eating mammalian meat such as beef, pork, lamb, venison, or other mammalian-derived products such as milk
Symptoms of tick-borne illness may include fever, chills, headache, fatigue, muscle aches, joint pain, swollen lymph nodes, or rash. Residents should contact a health care provider if they develop symptoms after a tick bite or after spending time in areas where ticks may be present, even if they did not see a tick
Residents should also seek medical advice if they experience delayed allergic symptoms after eating mammalian meat or mammalian-derived products; symptoms could include hives, swelling, stomach pain, vomiting, diarrhea, difficulty breathing, dizziness, or a severe allergic reaction. These symptoms may occur several hours after eating and could be related to alpha-gal syndrome
Ticks may be found in wooded, brushy, grassy, and leaf-litter areas, including backyards, parks, trails, fields, and other outdoor spaces. Many tick bites go unnoticed because ticks can be very small and their bites are often painless
To reduce the risk of tick bites:
- Avoid wooded, brushy, and grassy areas with high grass or leaf litter when possible.
- Walk in the center of trails.
- Wear long sleeves, long pants, and socks when spending time in tick habitat.
- Use an Environmental Protection Agency (EPA)-registered insect repellent labeled for ticks. Common active ingredients include DEET, picaridin, IR3535, oil of lemon eucalyptus, para-menthane-diol, or 2-undecanone. Always follow the product label. Products containing oil of lemon eucalyptus or para-menthane-diol should not be used on children under age 3.
- If using sunscreen, apply sunscreen first and insect repellent second.
- Consider permethrin-treated clothing and gear, especially for people who spend a lot of time outdoors, such as hunters, hikers, campers, and outdoor workers.
- Shower as soon as possible after coming indoors, preferably within two hours.
- Conduct a full-body tick check, including under the arms, in and around the ears, around the hairline, inside the belly button, behind the knees, between the legs, and around the waist.
- Check children, pets, coats, backpacks, and outdoor gear.
- Tumble dry clothing on high heat for at least 10 minutes to kill ticks on dry clothing. If clothes are wet or need washing, wash with hot water and then dry on high heat.
If a tick is attached, remove it as soon as possible using fine-tipped tweezers. Grasp the tick as close to the skin as possible and pull upward with steady, even pressure. Clean the bite area and your hands after removal. Monitor for symptoms and contact a health care provider if symptoms develop
Residents can also reduce ticks around the home by removing leaf litter, clearing tall grass and brush around the home and lawn edges, mowing regularly, keeping playground equipment and patios away from wooded edges when possible, and discouraging deer, rodents, and stray animals from entering the yard
For more information on tick bites and tick-borne illness, visit smchd.org/ticks
Vibrio
Vibrio are bacteria that occur naturally in brackish water, including the Chesapeake Bay and its tributaries. Vibrio bacteria are more common when water is warmer, especially from May through October
Vibrio bacteria can cause illness in two main ways: through contact with natural waters when a person has an open wound or through eating raw or undercooked shellfish, especially oysters
When Vibrio bacteria enter an open wound, they can cause serious infection. A wound may become unusually red, swollen, painful, or develop drainage. Severe infection can lead to hospitalization, intensive care, limb amputation, or death
People are at increased risk for severe Vibrio infection if they have liver disease, diabetes, a weakened immune system, iron overload disease or hemochromatosis, or take medications that reduce stomach acid
Vibrio infection can also occur when people cut themselves on objects or shellfish that have been in natural water. This may happen while handling live crabs, crab traps, oysters, or other equipment.
Some types of Vibrio infection can also occur from eating raw or undercooked shellfish. This may cause abdominal pain, vomiting, and diarrhea and can sometimes become severe
To reduce the risk of Vibrio infection:
- Avoid contact with natural waters if you have open wounds, cuts, scrapes, recent piercings, recent tattoos, or skin infections.
- If water contact is unavoidable, fully cover wounds with waterproof bandages.
- Wear water shoes to reduce cuts while in natural waters.
- Use extra caution and waterproof gloves when handling crabbing equipment, live crabs, oysters, or other shellfish.
- Carry soap and clean water so wounds that occur during water contact can be cleaned right away. If soap and clean water are not immediately available, use hand sanitizer and re-clean the wound with soap and clean water as soon as possible.
- Shower after contact with natural waters.
- Avoid eating raw or undercooked shellfish, especially oysters, if you are at increased risk for severe Vibrio infection.
- Remember that adding hot sauce or lemon juice to raw oysters does not kill Vibrio. Drinking alcohol while eating raw oysters does not prevent Vibrio infection.
Seek medical attention immediately if you develop a wound with unusual or expanding redness, swelling, pain, warmth, or drainage, especially after contact with natural waters. Tell your health care provider if you recently had contact with the Chesapeake Bay, its tributaries, or other natural waters
For more information on Vibrio, visit smchd.org/vibrio
Heat Safety
SMCHD strongly encourages residents to take precautions to prevent heat-related illness during the summer. The Maryland Department of Health reported in May the first heat-related death of 2026 in Maryland, which occurred in Calvert County
Heat-related illness can include heat cramps, heat exhaustion, and heat stroke. Warning signs may include muscle pain or spasms, headache, dizziness, nausea, vomiting, heavy sweating, weakness, confusion, disorientation, fainting, or rapid breathing
Heat stroke is a medical emergency. Call 911 right away if someone has a high body temperature, confusion, loss of consciousness, seizure, or hot, red, dry, or damp skin
To reduce the risk of heat-related illness:
- Drink plenty of fluids.
- Avoid alcohol and limit sugary drinks when spending time in the heat.
- Wear loose-fitting, lightweight, and light-colored clothing.
- Stay in the shade or air conditioning when possible.
- Avoid direct sunlight and wear sunscreen.
- Schedule outdoor work, exercise, and sports during cooler parts of the day, such as morning or evening.
- Take frequent breaks when working or playing outdoors.
- Check on older adults, neighbors, young children, people with chronic medical conditions, people who work outdoors, and people without reliable access to air conditioning.
Children and pets should never be left in a vehicle, even for a short time. Always check twice to make sure a vehicle is empty. Even on a 70-degree day, the temperature inside a vehicle can climb to over 100 degrees within half an hour
During periods of extreme heat, St. Mary’s County Government may open cooling centers. Cooling center announcements are shared through county communications, social media, and press releases
For more information and re
For local health updates, visit smchd.org or follow the St. Mary’s County Health Department on social media
