Documenting a tick bite: photograph and store it safely
In short: Take a photo on the day of the bite with a scale reference beside it, note the date, and repeat every few days. Keep the images somewhere that belongs to you — your own device, not a chat thread. The reason is simple: what actually helps a doctor is not today's picture but the progression.
Why the progression matters, not the moment
Erythema migrans — the characteristic skin change in Lyme borreliosis — appears, according to the Robert Koch Institute, some days to weeks after a tick bite. It often shows as a ring-shaped redness, paler at the centre than at the edge, and the red ring then gradually expands outward.
That is exactly where memory fails. Two weeks on, nobody can say for certain whether the redness was smaller back then, the same size, or whether there was anything at all. A dated photo answers that in two seconds. It does not replace an examination — it makes the examination better.
What makes the photo usable
Most phone photos of skin are useless because they cannot be compared with each other. Five things change that:
| What to do | Why |
|---|---|
| Put a scale reference beside it | A coin or a ruler. Without a scale you cannot tell later whether the redness has grown |
| Daylight, no flash | Flash blows out reds and flattens texture. Side light shows whether something is raised |
| Same distance and angle | Only then are two images genuinely comparable rather than merely similar |
| Record the date | It sits in the metadata, but metadata rarely survives forwarding or a screenshot |
| Several points in time | One on the day of the bite, then every few days. Only the series shows the progression |
If the tick is still attached, a picture before removal helps too — it shows size and life stage. The TickSpot camera freezes the frame on a tap, so you can zoom and save at your own pace instead of aiming one-handed. Then remove the tick properly: "How to remove a tick properly".
What does not belong in the frame
A photo of a patch of skin quickly becomes more than a patch of skin. A face, tattoos, jewellery, the living room in the background — all of it turns a medical close-up into an identifiable picture of a person. Get close enough that only the spot and the scale are in frame. That is not paranoia; it just saves you the question of who is allowed to see the picture later.
Storing them safely
Health data is specially protected in law. Article 9 of the General Data Protection Regulation counts data concerning health among the "special categories of personal data", whose processing is prohibited in principle and permitted only under narrow exceptions. The GDPR does not govern your own photos on your own phone — but it is a good yardstick for how carefully to treat them.
- Don't "send it to yourself". The quick route through a messaging app leaves a copy in a chat history, which in turn lands in backups — on devices and in accounts you weren't thinking about when you took the picture.
- Check automatic gallery sync deliberately. On most phones it is on by default. That isn't automatically bad, but it should be a decision rather than an accident. If you'd rather not: turn it off for this album.
- Screen lock and device encryption. Both are standard on current phones — checking takes a minute and protects more than anything else on this list.
- A separate album, not the main gallery. Prevents the accidental reveal during "look at this holiday picture" — the most common way such images get seen unintentionally.
- Delete them once the matter is settled. The images have a purpose. Once it is served, there is no reason to keep them.
For what it's worth: TickSpot processes the camera feed entirely locally in the browser and uploads nothing. An image only exists if you freeze it, and it only leaves the device if you tap save or share. That is why the app needs no account.
What to bring to the appointment
- The date of the bite — or at least the period, and where you had been.
- The images in chronological order, with the scale reference visible.
- How the tick was removed and whether anything stayed in the skin — see "Tick head stuck in your skin?"
- Changes in how you feel: fever, headache or muscle pain, fatigue. The RKI lists these as possible accompanying symptoms.
Find it first, then document it: TickSpot makes ticks visible in an inverted camera view — free, no sign-up, everything stays on the device.
Start the tick checkFrequently asked questions
Why photograph a tick bite?
Because the progression says more than a single look. Erythema migrans appears only days to weeks after the bite according to the RKI, and then expands outward. Without a picture from day one there is no reference point.
How do I photograph it properly?
Daylight rather than flash, a scale reference beside the spot, the same distance and angle every time, and note the date — a short series over several days beats a single photo.
Where do I store the images safely?
On your own device, in a separate album, with a screen lock and device encryption. Don't send them through messaging apps, and check automatic cloud sync deliberately.
How long should I keep them?
Until the matter has been settled medically. Then delete them — health photos with no remaining purpose are just a risk.
Sources
- Robert Koch Institute: Lyme borreliosis FAQ (erythema migrans: timing, appearance, accompanying symptoms — in German)
- Robert Koch Institute: Tick FAQ (removal without manipulating the tick — in German)
- Regulation (EU) 2016/679 (GDPR), Article 9 (health data as a special category)
Note: this article helps with documentation and does not replace a medical assessment. Redness after a tick bite, fever or lasting malaise should be looked at by a doctor — the images are an aid to that, not a substitute.