After a tick bite, how long for disease transmission?
A single tick bite can transmit several diseases. But investigators continue to debate how long a tick must be attached before it can transmit the Lyme disease bacterium. While many believe a tick must be attached for at least 36 to 48 hours before transmission can occur, others say it can happen within several hours.
People often ask: How long does it take for disease transmission to occur after a tick bite? According to investigators, Lyme disease may be transmitted faster if the tick previously fed on another host.
In a 2014 article entitled “Lyme borreliosis: a review of data on transmission time after tick attachment,” Michael J Cook explored the topic. “It is frequently stated that the risk of infection is very low if the tick is removed within 24 to 48 hours with some claims that there is no risk if an attached tick is removed within 24 hours or 48 hours.”
However, in animal models, Cook found, “transmission can occur in less than 16 hours, and the minimum attachment time for transmission of infection has never been established.”
Have you been bitten by a partially fed tick?
Investigators suggest that transmission time may be shorter if a tick has already fed on a host. A study by Shih and colleagues, found that, “Partially fed nymphal ticks transmit spirochetal infection more rapidly than do ticks that have never been attached to a host.”¹
So, how quickly a tick can transmit Lyme disease may depend on whether the tick had been partly fed BEFORE it attached to its second host.
Shih et al. demonstrated that partially fed nymphal ticks (84%) were capable of transmitting spirochetes to a non-infected mouse within 24 hours. The authors discovered it took less time for an infected nymphal deer tick to transmit Lyme spirochetes to a mouse if the tick was partially fed.
Ticks spontaneously detach from hosts
Individuals may mistakenly believe that once a tick bites it will remain attached throughout the entire feeding or until it is removed. But this isn’t the case.
In the mouse study, Shih found that ticks can spontaneously detach during the feeding process. And this action can profoundly impact the time it takes for spirochetes to infect the host.
“Virtually all nymphal ticks that previously had fed for 16 hours reattached efficiently.”¹
“We found that nymphs do detach spontaneously from free-ranging mice in the laboratory, perhaps as frequently as 15% of the time,” the authors report.
“Indeed, about [one tenth] of questing nymphs in nature seem to be distended, and reattachment by partially fed sub-adult ticks commonly occurs.”
In the laboratory, partially fed ticks would reattach to a second host and commence feeding. “Virtually all nymphal ticks that previously had fed for 16 hours reattached efficiently.”
What happens in partially fed ticks?
The tick attaches to a host, feeds and the Lyme bacteria multiply rapidly in the tick’s mid-gut. Normally, the tick eliminates all of the bacteria, leaving behind only those spirochetes that survive in the mid-gut before they molt into an adult.
But, in a partially fed tick, spirochetes multiply in the mid-gut and then move to the salivary glands.
If the tick bites again, the spirochetes residing in the salivary glands can be transmitted more quickly. “Partially fed nymphs [ticks] are able to reattach to another host and Lyme disease spirochetes may be transmitted by partially fed nymphs more rapidly than by nymphs that have not already fed.”
Pet owners: be wary
Their findings are particularly relevant to people who own pets. “These partially fed ticks may already have acquired spirochetal infection and avidly seek other hosts,” writes Shih.
“Pet ownership appears to be a risk factor for human Lyme disease, and this may reflect contact with ticks that have detached from a cat or dog within the household.”
If an unfed tick attaches it can take up to 36 hours to transmit the Lyme spirochetes to a mouse, Shih claims. “The chain of events that culminates in migration of the spirochetes from the gut of the tick to its salivary apparatus begins within the first day of attachment and requires at least another day for completion.”
Note: The study by Shih and colleagues was conducted only with mice and has not been replicated with humans.
Related Articles:
References:
- Shih CM, Telford SR, 3rd, Pollack RJ, Spielman A. Rapid dissemination by the agent of Lyme disease in hosts that permit fulminating infection. Infect Immun, 61(6), 2396-2399 (1993).
Adrienne Thoben
07/24/2023 (6:30 am)
Lyme disease and it’s plethora of debilitating symptoms is a man made bio weapon meant to take down humanity. TREAT IT AS SUCH! – Immediately and ferociously. It stuns me that these days, with what we all know is going on, that immediate treatment is even in question. We all must band together to secure Liberty when it comes to our health. How long a tick takes to infect should NOT even be a question deciding if and when to treat a tick bite victim. If someone can, in addition, find a cure for the rampant cognitive dissonance infecting the masses, put it out there.
Jessica
05/03/2023 (10:28 am)
We found a tick on my daughter’s leg and removed it with a tweezers but didn’t save it. I suspect it was present less than 6 hours, as she had been in taller grass picking up trash that same day (late April). Six days later, she developed a low grade fever, body aches and headache. The provider we saw didn’t think a tickborne illness that could transmit illness that quickly was likely to happen in MN. They feel like her symptoms are just related to a viral illness.
Should we get a second opinion? Do you feel like antibiotics are warranted in this case?
Thanks.
Dr. Daniel Cameron
05/04/2023 (2:38 pm)
I am concerned when my patients area ill within 4 to 6 weeks of a know tick bite. I have patients who contract a tick borne illness in less than 24 hours. I have had to make a case by case decision.
Annika
04/18/2023 (9:04 am)
I really appreciate this post and the detailed information. I learned that if a tick is manipulated it can “spill” the bacteria sooner, you did not mention this at all. Recently removed a tick that was in very firmly and ripped while trying to remove it. Removed second half in a second step. Adult black legged. There didn’t seem to be any clear engorgement nor obvious blood spilled but could have missed it if it was a tiny amount. Wondering if this unsuccessful process of removing it aka “manipulation” could have caused early transmission? So far no Symptome other than stuffy nose and cough starting the morning after removing it at night. Sent the tick in to ticknology.com inCO for testing, we’re in high lymes are in Wisconsin. Also wondering at what stage in attaching a tick bite starts to itch. This one didn’t. Mouth piece is still in. Also was it a mistake to not wash hands and the area immediately after removing?
Dr. Daniel Cameron
04/19/2023 (7:15 am)
I have seen patients without and without an itch. It is likely related to salivary secretions. I am not sure the presence of an itch tells anything. I remove the head but I not sure it makes a difference. I advise washing hands after removal but I am not sure it helps.
Suzanne
08/20/2022 (9:36 pm)
I was treated for Lyme with antibiotics a month ago and just now pulled a nymph out of my ankle. Do I need another dose of antibiotics? It hadn’t been there very long – maybe an hour.
Eric C
03/22/2022 (9:44 pm)
I’m 13 years old and recently went camping. After camping I got many symptoms of a cold. Two days later I found a tick in my skin but removed it quickly. It looked like a black legged tick. I’m paranoid that I have Lyme disease but have no symptoms other than a cold. Should I get checked for Lyme disease.
Dr. Daniel Cameron
03/23/2022 (6:55 am)
I have had a patients whose Lyme disease initially presented with viral Lyme symptoms that initially resolve. They later develop chronic issues. I am also concerned the the risk of an infection is higher if the tick is attached for 2 days. I have encouraged my patients with a similar story to be checked out.
Annika
04/18/2023 (8:56 am)
Can you specify what you mean with viral Lyme symptoms? Stuffy nose and cough are not indicating lymes, correct? But fever is? Would appreciate more info on that and how soon the symptoms can appear.
Dr. Daniel Cameron
04/19/2023 (7:13 am)
I have not found these symptoms alone to be helpful in considering a tick borne illness. I typically rely on the entire story.