Tick Test and Prophylaxis Proof

In the last 15 years, the number of cases of early Lyme disease in the
Netherlands has tripled to 22,000 per year, posing an increasing public health
burden. Antibiotic treatment of early Lyme disease is crucial as it can prevent
the development of late and more severe disease stages. However, infections can
initially remain undetected due to the diverse and often ambiguous nature of
clinical manifestations of Lyme disease. Furthermore laboratory diagnostics are
not always capable of detecting an early infection.
In the US, prophylactic antibiotic treatment after a tick bite has been shown
to prevent most Lyme disease. It has not been investigated whether prophylaxis
is effective in the Netherlands whereas transmission dynamics regarding ticks
and Borrelia species are different from the US. With 1.1 million tick bites per
year the recommendation of prophylaxis would result in very large numbers of
patients treated with prophylaxis.
For a future evidence-based guideline on prophylaxis, its efficacy in the Dutch
setting should be investigated. It should also be investigated to what extent
the NNT can be reduced by using tick-screening criteria (tick infection, tick
engorgement and attachment time) to assess the risk of Lyme disease after each
tick bite. If this tick-screening and subsequent preventive intervention
procedure proves successful, most Lyme disease is preventable with minimal use
of antibiotics.

To determine the efficacy of antibiotic prophylaxis after a tick bite in the
Dutch setting, in relation to tick infection, tick engorgement and attachment
time.

This is a randomized controlled intervention study. A maximum of 4500
participants reporting a tick bite will be included and randomly treated with
antibiotic prophylaxis or receive no further treatment. Participants in both
groups will be followed up for the development of Lyme disease.

The participants in the treatment group will take a single dose of doxycycline
in a dosage of 200 mg for adults and children of 8 years and older and above 50
kg body weight; in a dosage of 4 mg/kg doxycycline for children of 8 years and
older and below 50 kg body weight.

The participants in the treatment group may benefit of a possible effective
prophylactic treatment. As with the use of any medicinal product, the
participants may experience adverse events. Participants in the non-treatment
group have no direct benefit but also no additional risk.
All participants (including those not receiving prophylaxis) send their ticks
to the RIVM, and fill in online questionnaires at t=0, 1 wk and 1, 3, 6, 9, 12,
15 and 18 months after inclusion. Participants are advised to regularly check
the place of the tick bite and consult their GP if an erythema migrans or other
health complaints develop. This may have an indirect beneficial effect because
participants are triggered to pay attention for manifestations of Lyme disease.