From the Guidelines
The treatment for babesiosis should involve a combination of antimicrobial medications, with the standard regimen consisting of atovaquone plus azithromycin or clindamycin plus quinine for 7-10 days, as recommended by the Infectious Diseases Society of America 1. The choice of regimen depends on the severity of the disease, with clindamycin and quinine recommended for severe cases (A-III) 1.
- For adults, the dosage regimen of atovaquone plus azithromycin is atovaquone, 750 mg orally every 12 h, and azithromycin, 500–1000 mg on day 1 and 250 mg once per day thereafter by the oral route 1.
- For children, the doses are atovaquone, 20 mg/kg every 12 h (up to a maximum of 750 mg per dose), and azithromycin, 10 mg/kg per day once per day on day 1 (up to a maximum of 500 mg per dose) and 5 mg/kg once per day thereafter orally 1.
- The dosage regimen of clindamycin plus quinine for adults is clindamycin, 300–600 mg every 6 h intravenously or 600 mg every 8 h orally, and quinine, 650 mg every 6–8 h orally 1.
- For severe cases, clindamycin should be administered intravenously rather than orally, and exchange transfusion should be considered 1. The goal of treatment is to resolve the symptoms and signs of babesiosis and prevent relapse while minimizing the adverse effects of both antimicrobial therapy and exchange transfusion 1.
- Treatment should begin promptly upon diagnosis, as babesiosis can be life-threatening, particularly in immunocompromised individuals, the elderly, or those without a spleen.
- Follow-up blood smears are recommended to ensure clearance of the parasite, and some patients with persistent or relapsing infection may require longer treatment courses of 6 weeks or more.
From the Research
Treatment Options for Babesia
- The treatment for babesiosis typically involves a 7-10-day course of azithromycin plus atovaquone or clindamycin plus quinine 2.
- A study found that a regimen of atovaquone and azithromycin is as effective as a regimen of clindamycin and quinine for the treatment of babesiosis, with fewer adverse reactions 3.
- In immunodeficient mice, a combination of an endochin-like quinolone and atovaquone has been shown to provide radical cure of experimental babesiosis 4.
- Another study found that a combination of clofazimine and atovaquone is a potent therapeutic regimen for the radical cure of Babesia microti infection in immunocompromised hosts 5.
- Atovaquone has also been shown to be effective in the treatment of Babesia microti infections in hamsters, although recrudescences can occur when used as monotherapy 6.
Drug Resistance and Combination Therapy
- The emergence of drug resistance in B. microti has been defined as the development of a microbiologic relapse in association with clinical and laboratory abnormalities indicative of active babesiosis in a patient after 28 days of uninterrupted antibabesia drug therapy and while still receiving treatment 2.
- A combination of atovaquone and azithromycin has been shown to be effective in preventing the emergence of drug-resistant strains of B. microti 3, 6.
- The use of combination therapy, such as clofazimine and atovaquone, may be effective in treating Babesia microti infections in immunocompromised hosts and preventing the emergence of drug resistance 5.