Quinine and Babesiosis

While most know that quinine is used to successfully prevent and treat malaria, it is less well known that it can also treat an emerging disease called babesiosis.

Babesiosis is a parasitic disease that is transmitted by ticks. These parasites of the genus Babesia infect red blood cells. While more than 100 species within the genus have been reported, only a few have been identified to cause human infections, including Babesia microti, Babesia divergens, Babesia duncani and an as yet unnamed strain of Babesia divergens, designated MO-1.

Half of all children and a quarter of adults appear asymptomatic when infected with a Babesia parasite. For those who do develop symptoms, they are quite similar to malaria, because both cause fever (up to 40.5 °C ) and hemolytic anemia (destruction of red blood cells, because Babesia parasites reproduce in red blood cells). Symptoms appear 1 to 4 weeks after the bite of the tick. While uncommon, decreased levels of consciousness, coma or death are possible[1].

Babesiosis is a vector-borne illness usually transmitted by Ixodes scapularis ticks. Babesia microti uses the same tick vector as Lyme disease and ehrlichiosis, and may occur in conjunction with these other diseases.

In Europe, Babesia divergens is the primary cause of infectious babesiosis and is transmitted by Ixodes ricinus. In the United States, the majority of babesiosis cases are caused by Babesia microti, and occur primarily in the Northeast and northern Midwest from May through October. In Australia, babesiosis of types Babesia duncani and Babesia microti has recently been found in symptomatic patients[2].

Quinine can certainly be prescribed to treat babesiosis. However, the treatment of choice is a combination of antibiotic, because quinine has a bit more potential side effects.

Ticks are increasingly infected with all sorts of viruses, bacteria and parasites. Which means that, even in cooler climates, people are more at risk for malaria-like diseases such as babesiosis[3].

[1] Usmani-Brown et al: Neurological manifestations of human babesiosis in Handbook of Clinical Neurology - 2013  
[2] Gelfant et al: Babesiosis: An Update on Epidemiology and Treatment in Current Infectious Disease Report – 2003
[3] Ord et al: Human Babesiosis: Pathogens, Prevalence, Diagnosis and Treatment in Current Clinical Microbiology Reports - 2015