Tick-borne diseases are a major public health problem around the world. Ticks carry and transmit a variety of microbes that cause disease. These illnesses, which include Lyme disease, Rocky Mountain spotted fever, and Tularemia, can cause a variety of symptoms, often serious and sometimes deadly.
Now, just in time for spring and the explosion of ticks in forests, lawns and trails, a new study by researchers from the Beijing Institute, the Mudanjiang Forestry Central Hospital, Shanghai Jiaotong University and the University of Maryland have uncovered a never-before-seen illness transmitted by ticks. It’s possible that the disease could be a substantial health threat to humans and animals in areas where the carrier tick is common, state the team. The researchers have named the newly discovered bacterial species, Anaplasma capra. The paper is published in the journal Lancet Infectious Disease.
The researchers tested 477 patients in northeastern China who had been bitten by a tick over a month-long period in the spring of 2014. Of those, 28, six percent, were found to have been infected by the new species of bacteria. This microbe is related to other Anaplasma bacteria, some of which can cause illness when transmitted from ticks to humans. The team discovered one such disease, human anaplasmosis, two decades ago.
The team state that the symptoms of A capra infection include fever, headache, and tiredness, dizziness and muscle aches. The researchers successfully treated the infection with antibiotics, particularly doxycycline. Because no one knew the bacteria existed, no one has looked for it, and it is not clear how widespread it is. In China, the species appears to be common in goats, so the researchers decided to call it ‘capra’ because the word means goat in Latin. But it may also infect other animals. Currently, it is difficult to diagnose infection as there is no simple blood test.
The bacterium is probably transmitted via a tick species known as the taiga tick, explain the team. This species, which is closely related to the deer tick, lives in Eastern Europe and across Russia and Asia, including China and Japan. If this tick species transmits A capra throughout this area, human infection may be common. The researchers note that about a fifth of the world’s population, more than a billion people, live in areas where the tick resides.
The team state that this entirely new species of bacteria has never been seen in humans before, adding that there is still a lot to learn about the species, but it may be that this bacteria is infecting humans over a wide area. The team surmise that as the medical community understands more about these diseases, they are able to better address this growing international public health problem.
Source: University of Maryland School of Medicine (UM SOM)
