How dangerous is an encephalitic tick for pregnant women? - briefly
Encephalitic tick bites can cause severe neurological disease, and during pregnancy they raise the risk of miscarriage, fetal infection, and long‑term developmental complications. Prompt diagnosis and treatment are essential to mitigate these outcomes.
How dangerous is an encephalitic tick for pregnant women? - in detail
Ticks carrying the tick‑borne encephalitis (TBE) virus can transmit the pathogen during a blood meal. For a pregnant individual, the primary concerns are maternal infection, possible vertical transmission, and the impact on fetal development.
Maternal infection
- Incubation period: 7–14 days after the bite.
- Early phase: fever, headache, myalgia, fatigue; may be mistaken for a viral flu.
- Neurological phase (10–14 days after onset): meningitis, encephalitis, or meningoencephalitis; symptoms include stiff neck, altered consciousness, seizures.
- Hospitalisation required in 30–40 % of cases; mortality ranges from 1 % to 3 % in Europe, higher in older patients.
Vertical transmission
- Evidence of transplacental passage is limited; documented cases are rare.
- When maternal viremia occurs during the first trimester, theoretical risk to the embryo exists, but no consistent pattern of congenital anomalies has been established.
- In the second and third trimesters, the placenta may act as a barrier; reported fetal loss directly attributable to TBE is uncommon.
Fetal outcomes
- Fever and systemic inflammation in the mother increase the risk of preterm labour and low birth weight.
- Neurological complications in the mother can lead to reduced uterine perfusion, potentially affecting fetal oxygenation.
- No specific congenital syndrome linked to TBE has been identified in epidemiological surveys.
Diagnosis and management
- Serological testing for TBE‑specific IgM and IgG antibodies confirms infection; polymerase chain reaction (PCR) is useful in the early viraemic phase.
- No antiviral therapy is approved; treatment is supportive, focusing on fever control, hydration, and seizure management.
- Intensive care may be required for severe encephalitis; outcome improves with early recognition and monitoring.
Prevention for pregnant patients
- Vaccination with inactivated TBE vaccine is recommended in endemic regions; the vaccine is considered safe during pregnancy, with no increase in adverse pregnancy outcomes reported.
- Tick‑avoidance measures: wearing long sleeves and trousers, using permethrin‑treated clothing, applying EPA‑approved repellents containing DEET or picaridin, performing thorough body checks after outdoor exposure.
- Prompt removal of attached ticks reduces transmission risk; the tick should be grasped with fine tweezers close to the skin and pulled straight out without crushing.
Public health data
- Incidence of TBE in Europe averages 0.5–1.5 cases per 100 000 population; higher rates reported in forested, mountainous areas.
- Pregnant women constitute a small proportion of reported cases; surveillance data do not show a distinct increase in severity compared with the general adult population.
Overall, the threat posed by an encephalitis‑carrying tick to a pregnant individual is comparable to that for non‑pregnant adults regarding acute disease severity. The principal risks to the fetus stem from maternal systemic illness rather than direct infection. Preventive vaccination and strict tick‑avoidance practices are the most effective strategies to mitigate these risks.