Introduction:
In the 1980s, new skin disease was observed in Missouri and the southeastern United States, which had the characteristics of the typical rash seen in erythema lichens along with flu-like symptoms. In addition, the illness was associated with the bite of the Lone Star tick named Amblyomma americanum.
This disease is also known as Southern Lyme disease and Masters disease. However, the origin of southern tick-associated rash illness has been doubtful for the past 30 years in the non-endemic states, as the causative organism, Borrelia lonestari, is not isolated in all cases.
Southern tick-associated rash illness resembles the clinical criteria of Lyme disease but differs from it microbiologically. The rash is similar to that of erythema migrans but is smaller and more circular, with a central clearing with less uniformity in color and pattern.
What Is the Causative Agent for Southern Tick-Associated Rash Illness?
The initial polymerase chain reaction (PCR) showed that southern tick-associated rash illness is caused by a Spirochete tentatively named Borrelia lonestari. However, the available data shows that other etiological factors may also be responsible for the disease. It is transmitted by Amblyomma americanum or the lone star tick and is not spread through person-to-person contact.
Transmission of the disease takes place once the bacteria from an infected tick attaches itself and feeds in the host for 36 hours. The exact etiology of the disease is still unclear. However, it is clinically diagnosed based on a characteristic skin rash, mild symptoms, and occurrence in areas where Lyme disease is not present but where A. americanum ticks are present. Until an actual causative organism is identified, no definite diagnosis or treatment can be established.
What Are the Symptoms of Southern Tick-Associated Rash Illness?
The clinical manifestations of southern tick-associated rash illness include:
Sometimes other symptoms may also be present like:
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Stiffness of the neck.
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Arthralgia (pain in a joint).
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Regional lymphadenopathy (swelling of lymph nodes due to bacterial, viral, or fungal infections, autoimmune disease, and malignancy).
Southern tick-associated rash illness does not involve any long-term sequelae. The symptoms are similar to Lyme disease. Southern tick-associated rash illness lesions are usually noticed at the site of the tick bite, and fatigue is the most common sign in patients with skin lesions. A study in clinical infectious diseases shows some very minute differences between Southern tick-associated rash illness and Lyme disease. However, the patients often show similar symptoms in both conditions. The lesions that appear in Southern tick-associated rash illness are usually smaller in diameter and have a central clearing or a bull’s-eye appearance often seen in lesions of erythema migrans.
How Is Southern Tick-Associated Rash Illness Diagnosed?
Southern tick-associated rash illness has no definite diagnostic modality, and usually, the diagnosis is made based on clinical evidence. The diagnosis may also be associated with the geographic region where the infection occurs. The typical rash or a red bull’s eye lesion develops at the tick bite site, usually within seven days. The rash gradually expands to a diameter of 8 centimeters or more. The rash should not be confused with smaller areas of redness and tenderness at the site of the tick bite. Patients with this illness show symptoms of malaise, headache, fever, and body aches.
For instance, southern tick-associated rash illness is seen more commonly in central Texas and Oklahoma along with the southern states and the Atlantic coast. In contrast, Lyme disease is more prevalent in the northeast, mid-Atlantic, and upper midwest of the United States. It is essential to distinguish between southern tick-associated rash illness and Lyme disease because both show similar clinical manifestations. However, the causative agents for both diseases are different.
How Can the Southern Tick-Associated Rash Illness Be Avoided?
To avoid southern tick-associated rash illness, the following precautions must be taken:
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In tick-prone areas, people should wear light-colored clothes so that the ticks might be easily spotted and removed.
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Insect repellents should be used to avoid tick attachment.
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Once the tick is removed, the area should be appropriately cleaned with an antiseptic to prevent the bacteria from causing infection.
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If a person gets bitten by a tick, the tick should be removed carefully and steadily with the help of a tweezer. After removing the tick, the area of the bite should be adequately disinfected.
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The bite date should be recorded for reference in case the symptoms appear later.
What Is the Treatment of Southern Tick-Associated Rash Illness?
The suspected cases of Southern tick-associated rash illness often respond positively to a treatment regimen similar to that used for Lyme disease. The treatment is initiated with the antibiotics used to treat Lyme disease. Doxycycline should be given twice daily for 14 days. However, there is no approved treatment for this disease yet. Clinicians should be aware of this emerging zoonotic disease and its acute clinical presentation. Further studies need to be conducted about the causative organisms, laboratory testing, its prevalence, and proper treatment that should be given to patients with this disease.
Conclusion:
Southern tick-associated rash illness is an emerging illness that resembles Lyme disease. The characteristic feature is a bull’s eye rash similar to the inflammation in erythema migrans. The current incidence of southern tick-associated rash illness remains unknown. A study has suggested that Southern tick-associated rash disease is transmitted by Amblyoma americanum. The primary cause of this illness still remains unrecognized, and there is no specific medical diagnosis to identify its presence in the human body. However, it will take time before all the essential data is collected since various facts about the disease are still unknown. Patients suspected of having Southern tick-associated rash illness usually respond well to Doxycycline. The saliva from lone star ticks can irritate the bite site. The redness, discomfort, and tenderness at the bite site do not necessarily indicate the infection. Since the causative agent of the illness is still unknown, the treatment to cure Southern tick-associated rash illness is neither medically approved nor beneficial for the patient.
