Lyme disease is the most common tick-borne illness in the northern hemisphere, but not all ticks carry it. It’s caused by the bacterium Borrelia burgdorferi. Symptoms usually first present between three and 30 days after the infecting tick bite. The initial symptoms may be very mild and may even go unnoticed.
Your risk of contracting Lyme disease from a tick bite is determined by a variety of factors, such as the type of tick, the geographical location and the length of time the tick has been attached to your body. Most tick species need to be attached to their host for over an entire day before they can transmit any bacteria. The sooner the tick is removed, the less likely you are to have been infected with Borrelia burgdorferi.
Signs and Symptoms of Lyme Disease
The most distinctive early sign of Lyme disease is a circular, red ‘bull’s eye’ rash at the site of the tick bite. It tends to develop within four weeks, and it can be visible for up to three months.
The rash may also appear elsewhere on the body, and in 20–30% of patients it’s not observed at all. Other early symptoms of Lyme disease are normally flu-like, including:
- High body temperature or feeling hot and shivery;
- Muscle and joint pain;
- Fatigue and malaise.
Lyme disease is usually successfully cured with a course of oral antibiotics when diagnosed early. More severe symptoms may develop months or even years later if the infection is left untreated, such as:
- Joint pain, swelling and stiffness;
- Pain or numbness in the limbs;
- Heart problems;
- Trouble with memory or concentration.
The Link Between Lyme Disease and Autism
Does Lyme disease cause autism? Is autism a symptom of Lyme disease? A possible link between Lyme disease and autism was first suggested in 2008. Nowadays an increasing number of patients believe that the neuropsychiatric symptoms associated with autism may result from the immune response to Borrelia burgdorferi following a tick bite.
However, most recent studies have failed to find any connection between Lyme disease and autism. For instance, researchers and clinicians at Weill Cornell Medical College and Columbia University Medical Centre have examined the blood samples and medical records of 120 children. Most of the children were living in the Northeastern and Western United States, where Lyme disease cases are known to predominantly occur. Seventy of the children had been diagnosed with autism, and the rest were their siblings.
When testing the autistic children’s blood samples for signs of exposure to Borrelia burgdorferi, the scientists found that only one of them had produced antibodies against the bacteria. However, four out of the 50 children without autism tested positive for the antibodies. Nonetheless, the sample size of this study was quite small, and therefore the results may not be statistically significant. The researchers have acknowledged that their findings neither disprove nor prove the claim that Lyme disease may in some cases cause behavioural changes resembling those seen in autism.
Lyme Disease Diagnosis
Lyme disease can be difficult to diagnose because most of its symptoms resemble those of non-specific viral illnesses. The presence of the characteristic rash greatly aids diagnosis. In the absence of the rash, doctors have to consider many factors, like the patient’s history of tick bites and any recent visits to high-risk areas.
Laboratory tests are available, but false negative results are extremely common in the first few weeks after infection has occurred. They tend to be more reliable later, as the body begins to produce more antibodies to fight the bacteria. Some of the most commonly ordered test are:
- ELISA (enzyme-linked immunosorbent assay), which detects antibodies against Borrelia burgdorferi;
- Western blotting, which also checks for antibodies, is usually used to confirm the result of a positive ELISA test;
- Polymerase chain reaction (PCR), which is mostly carried out in cases where Lyme disease is suspected to have caused joint or neurological symptoms.
Lyme Disease Treatment
The sooner Lyme disease is diagnosed, the better the patient’s chances of a quick and complete recovery. Early treatment consists of antibiotics taken for 14 to 21 days. The most common drugs used to treat of Lyme disease are doxycycline, cefuroxime and amoxicillin.
Persistent and chronic Lyme disease is normally treated with intravenous antibiotics for several weeks. If the bacteria have spread all over the body, it may take a while for all the different symptoms to completely vanish.
Lyme Disease Prevention
While the answer to the question ‘can Lyme disease cause autism?’ is no, it’s still important to protect yourself from the disease. The only guaranteed way to prevent Lyme disease is by avoiding tick bites. Ticks can’t fly or jump, but they live on grass, bushes and trees, where they wait for a potential host to pass them by close enough so they can cling to them. Below are some useful tips to help prevent tick bites:
- Wear long sleeves and long trousers – and tuck your trousers in your socks!
- Wear lightly coloured clothing.
- Keep to the centre of the trail in forests.
- Wear an insect repellent containing DEET on your clothing.
- For enhanced protection, use a product containing permethrin on your clothing and camping equipment.
- Take a hot shower or bath and wash your hair within two hours of arriving home from a forest, moorland or grassy area.
- Thoroughly check yourself and any children and pets for ticks.
- Wash your clothes and then put them in a tumble dryer for an hour. (Ticks may survive in the washing machine, but the high heat in the dryer will definitely kill them.)