Babesiosis

Babesiosis is a vector-borne parasitic disease transmitted to humans by an infected tick. There are many identified species but only a few are responsible for human infections.

In the case of 1 species, Babesia microti, it cycles between a rodent and the Ixodes tick. Humans are accidental, dead-end hosts. In other words, an infected individual cannot transmit the disease to another person. It can, however, be acquired through blood transfusion, organ transplantation and via the placenta during pregnancy.

Babesiosis can cause serious disease in individuals who are:

• immunocompromised or
• without spleens or
• have poorly functioning spleens

Babesiosis is an emerging tick-borne disease. The parasite is found worldwide.

The disease was first identified by Romanian biologist, Victor Babes in 1888. He noted the microorganism in the red blood cells of cattle. The cattle were found to have blood in their urine.

The first recognized human case was reported in Yugoslavia in 1957.

The disease is usually mild, or asymptomatic but severe disease can occur.

According to CDC a total of 16,456 cases were reported between 2011 and 2019. Of these, 98.2% were in 10 states (Connecticut, Maine, Massachusetts, Minnesota, New Hampshire, New Jersey, New York, Rhode Island, Vermont and Wisconsin). It is not reportable in a number of states.

The disease is likely underreported (unrecognised) around the world.

The risk of Babesiosis is very low in travellers. Travellers should always be reminded of the risk of tick-borne disease if their activities are likely to increase exposure. The time of travel is also very important. Ticks are most active during Spring and Summer.

Those most at risk include hikers, campers, and those involved in outdoor work. An outdoor worker in a region of risk is 10 times for likely to be infected than the general population.

Two main factors determine the risk of tick habitation in a particular area. These are vegetation and climate. This makes it possible for local authorities to warn visitors of the possibility of tick habitation in a particular area.

If forewarned, then the visitor is able to reduce their exposure to ticks.