What is the recommended Lyme disease prophylaxis for a 15-month-old child with a tick bite (Ixodes tick) one week ago?

From the Guidelines

Prophylactic antibiotics are not recommended for a 15-month-old with a tick bite from one week ago. The window for effective prophylaxis is within 72 hours of tick removal, so at one week post-bite, prophylaxis would no longer be appropriate 1. Instead, the child should be monitored for symptoms of Lyme disease, including fever, rash (particularly the characteristic erythema migrans "bull's-eye" rash), fatigue, headache, or joint pain over the next 30 days. Some key points to consider in this case include:

• The tick must be identified as an Ixodes species (deer tick) for prophylaxis to be considered, and even then, it must have been attached for at least 36 hours 1.
• The local rate of infection of ticks with Borrelia burgdorferi should be at least 20% for prophylaxis to be considered 1.
• Doxycycline is relatively contraindicated in children under 8 years old, and there is no recommended alternative for prophylaxis in this age group 1. If symptoms develop, the child should be evaluated promptly for possible Lyme disease treatment. For children under 8 years old with confirmed Lyme disease, amoxicillin is the preferred treatment, however the specific details of the treatment should be determined on a case by case basis 1.

From the FDA Drug Label

For children above eight years of age: The recommended dosage schedule for children weighing 100 pounds or less is 2 mg/lb of body weight divided into two doses on the first day of treatment, followed by 1 mg/lb of body weight given as a single daily dose or divided into two doses, on subsequent days. For the prophylaxis of malaria: For adults, the recommended dose is 100 mg daily. For children over 8 years of age, the recommended dose is 2 mg/kg given once daily up to the adult dose. Inhalational anthrax (post-exposure): ADULTS: 100 mg of doxycycline, by mouth, twice a day for 60 days. CHILDREN: weighing less than 100 lb (45 kg); 1 mg/lb (2.2 mg/kg) of body weight, by mouth, twice a day for 60 days.

The child in question is 15 months old, which is below the age of 8 years. Doxycycline is not recommended for children under 8 years of age.

• The dosage for children under 8 years is not provided in the label.
• No conclusion can be drawn for the use of doxycycline in a 15-month-old child for Lyme prophylaxis.
• Cefuroxime axetil label does provide information on early Lyme disease treatment, but it is for patients with erythema migrans, and the dosage is for adults and children, but no specific information is provided for a 15-month-old child.
• No recommendation can be made based on the provided drug labels for a 15-month-old child with a tick bite 1 week ago 2, 3.

From the Research

Lyme Prophylaxis for Children

• The use of single-dose doxycycline as prophylaxis for Lyme disease after a tick bite has been studied in various populations, including children 4, 5, 6.
• However, the specific use of doxycycline in children under 15 months old is not explicitly mentioned in the provided studies.
• According to the study by 5, children are at increased risk of Lyme disease, and the disease can be transmitted to humans through the bite of the Ixodes tick.
• The study by 6 found that a single dose of doxycycline after a tick bite can prevent the development of Lyme borreliosis in individuals aged 8 years and older.

Treatment Options for Lyme Disease

• The treatment options for Lyme disease include doxycycline, amoxicillin, cefuroxime axetil, and erythromycin 5, 7, 8.
• Doxycycline and amoxicillin are considered first-line treatment options for early-stage Lyme disease 7.
• Cefuroxime axetil has been shown to be equally effective as doxycycline in treating early Lyme disease and preventing late Lyme disease 8.

Prophylaxis for Lyme Disease

• A single dose of doxycycline after a tick bite can prevent the development of Lyme borreliosis in North America and Europe 5, 6.
• The study by 6 found a relative risk reduction of 67% and a number-needed-to-treat of 51 for prophylaxis with doxycycline after a tick bite.
• However, the use of prophylaxis in children under 15 months old is not explicitly recommended in the provided studies, and the decision to use prophylaxis should be made on a case-by-case basis, considering the individual risk factors and medical history 4, 5.