Virus World

Tick-borne diseases of all kinds are on the rise in the U.S., up by more than 10,000 cases from 2016 to 2017. The deer tick, also known as the black-legged tick, is a common summer nuisance. It's also a danger: Because ticks feed on the blood of human and animal hosts, they often pick up and spread germs from meal to meal. As a result, they can trasmit all kinds of nasty illnesses, from parasites to bacterial infections, to their human hosts. Ticks can be found in grassy or wooded areas, and are active any time temperatures are above freezing. Still, they're most common in spring and late summer to autumn, according to the New York Department of Health.

Two cases of the Powassan virus have been discovered in northern new Jersey, and a case was also confirmed in Maine, where the disease had not been seen since 2017, CNN reported. The virus causes fever, headache, vomiting, and fatigue. Severe cases can be fatal, since the virus can cause infection of the brain and spinal cord, resulting in disorientation, seizures, and loss of coordination and speech, according to the CDC. Long-term side effects can include loss of strength and memory problems. There is no treatment, and INSIDER previously reported that people infected have about a 50% chance of permanent damage and a 10% chance of death. 

Ticks discovered in New Jersey now have spread into neighboring states. "For the first time in 50 years, a new tick species has been identified in the U.S.," says Dr. Gregory Poland, director of the Mayo Clinic Vaccine Research Group.

"Haemaphysalis longicornus, or the Asian longhorned tick, is in eight states already in the Northeast region of the U.S., primarily affecting livestock." Dr. Poland says the longhorned tick is prolific and can lay as many as 2,000 eggs at a time. "In Asia, it causes a devastating disease called "SFTS"—severe fever and thrombocytopenia syndrome. About 15% of those people have died. It has not happened in the U.S. yet, but epidemiologists are watching closely," says Dr. Poland.

The Centers for Disease Control and Prevention says tick-borne illnesses such as Lyme disease have doubled over the past 13 years. Lyme disease is the most common, accounting for approximately 82% of all tick-borne cases. Dr. Poland says two recently discovered viruses, the Heartland and Bourbon viruses, also may be connected to ticks, but researchers do not yet have enough information.