How long can a tick be stored in a refrigerator? - briefly
Ticks can be kept refrigerated at about 4 °C for up to six months without significant loss of viability, though most laboratories limit storage to three–four months to preserve DNA quality. Longer periods increase the risk of degradation and reduced success in subsequent analyses.
How long can a tick be stored in a refrigerator? - in detail
Ticks can remain viable in a standard laboratory refrigerator (approximately 4 °C) for several weeks to a few months, depending on species, developmental stage, and storage conditions. Adult hard ticks (Ixodidae) retain the ability to feed after 4–6 weeks, while nymphs and larvae may survive up to 8–12 weeks. Soft ticks (Argasidae) often endure longer periods, sometimes exceeding three months, because they are adapted to cooler, more stable environments.
Key factors influencing survival:
- Temperature stability – fluctuations above 8 °C or below 0 °C accelerate metabolic decline and increase mortality.
- Humidity control – placing ticks in a sealed container with a moist cotton plug or damp paper maintains relative humidity around 80 %, preventing desiccation.
- Substrate – a small amount of sterile leaf litter or filter paper reduces stress and mimics natural microhabitats.
- Species‑specific tolerance – for example, Ixodes scapularis tolerates up to 6 weeks, whereas Rhipicephalus sanguineus can survive 10–12 weeks under identical conditions.
Guidelines for optimal refrigeration:
- Place individual ticks in labeled microcentrifuge tubes or vials.
- Add a damp sterile substrate; avoid liquid water that could cause drowning.
- Seal containers tightly to maintain humidity and prevent cross‑contamination.
- Store at a constant 4 °C; monitor the refrigerator thermometer weekly.
- Use ticks within the recommended time frame; after 12 weeks viability drops sharply, and DNA quality may degrade for molecular analyses.
If the purpose is DNA extraction rather than live‑tick studies, specimens can be kept longer—up to six months—provided they are frozen at –20 °C or lower. Freezing preserves nucleic acids but eliminates the ability to assess feeding behavior or pathogen transmission.