Ticks are small parasitic organisms that feed on the blood of mammals, birds, reptiles and even amphibians. When looking for a host, ticks do not technically have a preference for a certain blood type like mosquitos do. However, there are some theories on whether certain blood types make a person more attractive to ticks.
Do ticks have a preference for a certain blood type?
Ticks do not actually have preferences for certain blood types like mosquitos. Mosquitos are attracted to the carbon dioxide, flavors, and scents we exhale, while ticks use other cues like body heat, moisture, vibration and visual contrasts to find hosts. They are not attracted by blood type. Once they latch onto a host, ticks ingest blood through their bite while also injecting saliva. The saliva contains an anesthetic so the host does not feel the bite, as well as substances that prevent blood from clotting. Ticks can feed for several days before dropping off.
Theories on blood type preference
While ticks do not directly target specific blood types, there are some theories that certain blood types may make a person more attractive to ticks:
Blood type O
One theory is that people with blood type O may be more prone to tick bites. Some research has suggested that those with blood type O attract slightly more mosquitos than other blood types. This may extend to ticks as well since both insects are looking for a blood meal. However, any impact of blood type O on tick attraction would likely be small.
Blood type B
Blood type B has been associated with increased risk for chronic Lyme disease. Those with blood type B may have an impaired immune response to Borrelia burgdorferi, the bacteria that causes Lyme disease. This could allow the infection to last longer and become chronic. However, there is no evidence that those with blood type B attract more ticks initially.
Rhesus factor
Blood type refers to the AB0 group (A, B, AB, or O) as well as the Rhesus (Rh) factor. Those who are Rh negative may theoretically be slightly more prone to initial tick bites. The reason is that Rh negative individuals often have increased baseline histamine levels. Since histamine levels rise in response to tick bites, this could potentially make Rh negative people more sensitive and reactive. However, the effect would likely be small.
No strong preference
While these theories exist, there is no definitive evidence that ticks directly target or prefer anyone based on ABO blood group or Rh factor. Some small differences may exist in tick attraction or reactivity to bites among blood types, but this does not amount to a major preference. Overall, ticks do not seem to seek out certain blood types over others when choosing a host.
Other factors that may influence tick attraction
Rather than blood type, ticks seem to be much more influenced by other factors when seeking hosts:
Blood carbon dioxide and heat
A person’s breath and body heat attract ticks looking for a meal in the vicinity. Ticks sense carbon dioxide, warmth, and humidity. People and animals exhale more carbon dioxide and emit more heat when active, making them more noticeable.
Skin emissions
Ticks can detect odors, flavors, and other compounds emitted through the skin. Increased physical activity and sweat may make human hosts more detectable.
Visual contrasts
Ticks sense motion and are drawn to high visual contrast. Therefore, they may gravitate toward exposed skin, clothing edges, moving appendages or any areas of contrast between light and dark.
Vibrations
Ticks sense vibrations through organs called Haller’s organs. Therefore, walking through brush or tall grass may alert ticks to potential hosts.
Chemicals in sweat
Certain chemicals present in human sweat, especially lactic acid, seem to be attractive to ticks. Increased physical activity can make people more sweaty and noticeable.
Blood ammonia
Ticks can detect ammonia, a compound found in exhaled breath but also in blood and emitted through skin. Ammonia attracts ticks. After exercise, ammonia levels rise, which could make someone more attractive.
Do certain blood types impact tickborne disease risk?
While blood type does not appear to change risk for being bitten by ticks, there are some theories about how blood type may influence susceptibility to certain tickborne infections:
Lyme disease
As mentioned earlier, those with blood type B may face higher rates of developing chronic Lyme disease. The immune systems in this blood type may have more difficulty overcoming Borrelia burgdorferi. However, risk of early Lyme is not impacted by blood type.
Babesiosis
Babesiosis is caused by Babesia microti parasites from tick bites. Research suggests blood type O may face higher risk of contracting Babesia parasites, while type A1 may have protection against this infection.
Anaplasmosis
Limited studies suggest blood type B is associated with higher risk for anaplasmosis, which is bacterial. Blood type O may potentially have a protective effect.
Powassan virus
Blood types A and AB have been associated with increased incidence of Powassan virus neurological disease from tick bites. Type O showed lower rates.
Rocky Mountain Spotted Fever
No link has been seen between this tickborne bacterial disease and blood type preferences. RMSF risk appears unrelated to blood type.
Protecting yourself from ticks
Regardless of your blood type, you can take steps to prevent tick bites and reduce chances of contracting a tickborne illness:
– Use insect repellent when going into wooded, brushy or grassy areas where ticks thrive. Repellents with DEET, picaridin, IR3535 or oil of lemon eucalyptus can be applied to skin or clothing.
– Wear light colored long sleeves and pants when outdoors to cover skin and allow you to spot ticks more easily. Tuck pants into socks.
– Stay in the center of trails when hiking and avoid high grass or dense brush.
– Conduct frequent tick checks after being outdoors and remove ticks promptly using tweezers or a tick removal tool. Look carefully on all parts of the body and clothing.
– Shower after outdoor activity to wash off any possible ticks. Ticks need to be attached for longer to transmit disease. An engorged tick can be spotted more readily.
– Consider treating clothing, gear, or outdoor spaces with insecticide containing permethrin. This repels ticks.
– Ask your doctor about vaccinations against certain tickborne diseases like Lyme or tickborne encephalitis.
Conclusion
Ticks do not specifically seek out certain blood types. While theories exist on blood type O, B, and Rh status making people marginally more attractive to ticks or reactive to bites and infections, the effects are small. Ticks are much more responsive to carbon dioxide, heat, sweat, motion and vibrations when looking for a potential host. Ultimately, personal protective measures like repellents, clothing choices, prompt tick checks and possibly vaccination provide the best protection from tick bites. Knowing your risk areas, being observant outdoors, and acting quickly to remove attached ticks can greatly slash your chances of contracting a tickborne illness.