Rates of a potentially deadly tick-borne parasitic disease that can cause paralysis are on the rise.
Every year babesiosis, sometimes referred to as ‘American malaria’, has increased by an average of 9 per cent between 2015 and 2022 in the US, according to researchers.
Additionally, two in 5 of these patients were also found to be co-infected with Lyme disease or another tick-borne illness.
While found primarily in Northeastern and Midwestern states of the US the tick-borne disease also reached Britain four years ago
Babesiosis, caused by a parasites called Babesia microti carried in ticks’ saliva, which from there begin to infect a person’s red blood cells destroying them.
Every year babesiosis, sometimes referred to as ‘American malaria’, has increased by an average of 9 per cent between 2015 and 2022 in the US, according to researchers
The disease is caused by a single-celled organism that attacks red blood cells when it infects humans
While a healthy adult can normally shake off the infection it can be deadly with older adults and those with health conditions or treatments that weaken their immune system at particular risk.
Like malaria, the parasite infects red blood cells, causing anemia and the condition shares many similar clinical symptoms.
While about two thirds of people with the infection have no symptoms, those that do, develop them in two phases.
First, the infected experience a flu-like illness such as a fever, headache and fatigue.
It then progresses to a more serious second phase where the body’s central nervous system becomes disrupted, leading to problems with the spinal cord and brain such as meningitis, encephalitis and paralysis.
While most cases are caused by tick bites, less common ways of getting infected with babesiosis include getting a blood transfusion that has the parasite in it or a mother with the infection passing it on to her baby during pregnancy.
Changes in temperature humidity, rainfall and length of season may have influenced the population and distribution of ticks in the US and across Europe as well as the population of animals that serve as reservoir hosts, like deer.
As a result, ticks may be present in a wider geographical area.
Getting rid of a tick from your own skin is crucial to avoid the risk of infection, or contracting other diseases including Lyme disease. The NHS has a four-step routine to help safely spot and remove ticks
Although rare in the UK, cases of babesiosis have been reported and the charity Lyme Disease Action say it’s another disease both medics and the public should be aware of.
Health officials confirmed a case of the tick-born disease in the UK on July 31, 2020 in Devon.
Lyme disease — another tick-borne disease which causes a circular rash around the bite, as well as a fever, headache and tiredness — strikes thousands of Brits every year.
The bacteria was detected among more than 1,000 people across the country in 2022.
But, in addition to these laboratory-confirmed cases, there is an estimated 1,000 to 2,000 additional cases of the bacterial infection each year.
As a result, charity Lyme Disease UK says that 3,000 to 4,000 people in England and Wales are affected annually.
Provisional ONS data for 2021 shows that there were 1,156 lab confirmed cases of Lyme disease in England and wales
The study published in the journal Open Forum Infectious Diseases assessed the prevalence of the disease as well as the affect of patients being infected with multiple tick-borne diseases.
Using the TriNetX, a large, national database of clinical patient data from over 250 million individuals, they identified 3,521 people who were infected with babesiosis between October 2015 and December 2022.
The researchers found that the incidence of babesiosis increased an average of 9 per cent per year.
The majority of cases peaked during the summer months and were reported in Northeastern states. Of those diagnosed with babesiosis, 42 per cent were infected with one or more additional tick-borne disease, which is a higher rate than what’s been found in previous studies.
The greatest percentage of those patients, 41 per cent, were co-infected with the bacterium responsible for Lyme disease.
The above map shows states in the US that have reported cases of babesiosis and the disease prevalence. It is endemic in states in the northeast, midwest and west, and has also been recorded in the south
This graph, provided by the CDC, shows how many cases of babesiosis have been recorded in the US by year. In 2011 there were just over 1,000 cases, but now this has grown to 2,500
When researchers examined if being infected by two tick-borne diseases led to worse outcomes, they found there were no significant differences between the babesiosis-only group and the co-infection group.
However, when they looked at mortality risk, they found that the risk of death was higher among the babesiosis-only group.
‘Having both babesiosis and Lyme disease seemed not to be associated with worse mortality,’ Paddy Ssentongo infectious disease fellow, Penn State Health Milton S. Hershey Medical Center and lead author of the study said.
He added that the finding was surprising. He said: ‘It’s speculated that the concurrent presence of other tick-borne infections in the blood could alter the immune response by possibly “boosting” it to effectively fight infections.’
However, this difference in outcomes may be a result of how the tick-borne diseases are treated.
In their study, the team found that the co-infection group was more likely to be prescribed doxycycline, the first line antibiotic treatment for Lyme disease, anaplasmosis and ehrlichiosis, compared to the babesiosis-only group.
Which researchers suggested could suggest the drug doxycycline is also effective in treating the babesia parasite.
Currently, the treatment of babesiosis depends on disease severity.
Treatment typically includes a combination of the antibiotics azithromycin and atovaquone.
Red blood cell exchange, where abnormal red blood cells are removed and replaced by healthy ones, can also be considered for severely ill patients such as those with serious organ dysfunction.
‘For patients with babesiosis, we add on doxycycline as we’re investigating whether or not the patient has Lyme disease or other tick-borne diseases, and we’ve seen better outcomes at our medical center with this approach,’ Dr Ssentongo said.
He said that there are other case reports where babesiosis has been successfully treated with doxycycline. However, more research is needed to understand the physiological pathways that underlie co-infection and how that might influence treatment protocols.
But the most effective treatment approach is preventing tickborne-diseases in the first place, according to Dr Ssentongo.
To avoid tick-borne diseases you should wear long-sleeved shirts, trousers and light-colored clothes. It’s also recommended to use tick repellant and check for ticks after spending time outdoors.
