Anaplasmosis in the USA (Maine)

13 Nov 2017

There were 411 cases of anaplasmosis Link in Maine from January to September 2017. Case numbers have risen in recent years, from a total of 94 in 2013. Case numbers have risen in recent years, from a total of 94 in 2013.

Anaplasmosis is caused by the bacterium Anaplasma phagocytophilum, part of the Rickettsia group of bacteria that cause Rocky Mountain spotted fever and typhus. The infection is transmitted by the same deer ticks that transmit Lyme disease, Ixodes scapularis in the eastern USA and Ixodes pacificus in the west.

While the disease is rarely fatal, it tends to be more severe in those who are elderly, immunosuppressed or have other health problems. Influenza-like symptoms are typical.

Doxycycline is the first line of treatment.

Recommendations for Travellers

There is no vaccine available against anaplasmosis The main preventive measure is to avoid being bitten by ticks.

Important points to consider:

Be aware of the tick risk. Risk areas include woodland, moorland, parkland, heaths and gardens with wildlife. Areas with deer and sheep are risky.
Ticks are more common from April to October.
Activities such as camping, picnics, hiking and cycling can increase risk.

Preventing tick bites and transmission:

Ticks adhere to the ends of grasses, vegetation and foliage and are easily transferred to humans as they brush past, sit/lie on the grass etc. Keep to the footpath where possible and do not sit directly on the grass.
Practice insect bite avoidance: protect the skin; wear long trousers/sleeves and tuck trouser bottoms into socks. Use repellent on any exposed skin, one that contains DEET 30-50%.
Clothing can be pre-treated with permethrin insecticide for added protection.
Wear light coloured clothing as it is easier to see the ticks against a light background.
At various times, especially at the end of the day, examine the skin for ticks. Ticks are about the size of a pin head before they feed so may easily be missed.
When checking for ticks it is important to inspect warm, moist areas like the skin folds behind the knees, elbows and groin area. Check each others back and examine the neck, head and scalp of children carefully.
It is important to remove the tick early as it does not feed immediately and transmission of infection may be avoided if it is removed as soon as possible.
Do not cover the tick in any substance before removing e.g. petroleum jelly, oil or lotion and do not attempt to burn the tick.
Ticks can be removed with tweezers or a proprietary remover (available from vets or pharmacies). Grasp the head of the tick as close to the skin as possible and pull steadily in a vertical direction; try not to squeeze the body of the tick as this may transmit infection.
Make sure that ticks are not carried home on clothing, children or the family pet dog.
If you develop a rash or sore around the tick bite or feel unwell, consult your doctor and tell them that you have been bitten by a tick.