Thursday, August 15, 2013

Anaplasmosis - the other tick disease

There is a new kid in town - Anaplasma phagocytophilium. This bacterium is carried by the same deer ticks that bring us Lyme disease. Prime time for tick diseases is May through August. The symptoms are different but the course of action is the same - get diagnosed, get treated.

Lyme disease signs and symptoms start subtly. If the stricken person missed the actual bite, then the first sign is often (but not always) the signature rash. Fever, chills, fatigue, muscle ache and a headache may (or may not) accompany the rash. Only after weeks to months after the rash (which does not always occur) and the initial set of symptoms (ditto) are gone is there a possibility that the really bad consequences set in: arthritis, partial facial paralysis, meningitis, limb weakness, and so forth (or not).

In stark contrast, the symptoms of anaplasmosis are more akin to being run over by a car, having it circle around to hit you again, and then one more time to park on your head. Or in gamers' terms, "All your base." [Look it up.]

Some 7 to 10 days after the bite the anaplasmosis symptoms arrive all at once: extreme fatigue, high fever, uncontrollable shivering alternating with profuse sweating, night sweats, headache, nausea, abdominal pain, loss of appetite, muscle pain, cough, mental confusion, and extreme fatigue. Really extreme. The Centers for Disease Control (CDC) uses the term "malaise," but this does not convey the soul-crushing lethargy of a full-speed Anaplasma assault.

Not everyone exhibits all the symptoms, and many of these symptoms overlap with the flu and other diseases, either causing many people to delay seeking a medical evaluation, or doing so and getting a misdiagnosis.

Actually, these days a diagnosis is straightforward. Do you have some or all of that litany of symptoms, especially fever and fatigue? Were you in any place a week or two ago where there might have been ticks? Do you have any symptoms which hint you may have something else? If not the last, that's it. A blood sample will be taken, but early in the course of the infection the test results can be falsely negative (results say you don't, but you do). Standard medical practice is to start antibiotic treatment immediately. Treatment should never be delayed until the lab results are back. Standard treatment is the same as for Lyme - two weeks of doxycycline.

Not treating an Anaplasma infection in a timely fashion can have serious consequences. Especially in older or immuno-compromised people there are risks of compromised breathing, kidney failure, nerve damage... Treatment may require hospitalization and intravenous antibiotics. Deaths are rare (less than one percent).   

Anaplasmosis does not appear to be casually contagious. As a blood-borne disease it could in theory have the same vector as HIV/AIDS, but there is no mention in the science literature of transmission via sexual contact. There are confirmed reports of infection from blood donations, and in theory the same risk would apply to organ transplant recipients. Currently there are no good blood or organ donor screening tests.

As noted, Anaplasma is carried by the same tick as Lyme disease. Reported cases of Lyme number about 30,000 per year. This is accepted as an undercount, as many people do not seek medical assistance, and so were never diagnosed. Others sought medical help and were misdiagnosed (keep in mind the false negative problem with blood tests also applies to Lyme). And finally, some were correctly diagnosed but not reported to the appropriate health agency. With the same caveats in mind, the anaplasmosis report for 2010 (the latest year with national data) was 1,761 cases. Hotspots for both diseases are the Northeast and the upper Midwest.

 NEWS FLASH: On August 18, 2013, the Centers for Disease Control revised its estimates of numbers of new Lyme disease cases per year from 30,000 to 300,000. This 10X increase was the result of survey blood testing laboratories for numbers of positive blood tests, versus the old method of depending solely on reports from physicians. All physicians are supposed to report all confirmed or suspected Lyme disease to the CDC, but obviously, this has not been true. It is likely that other tick borne diseases are under reported.

More information on tick-vector diseases can be seen as the CDC website: http://www.cdc.gov/ticks/. The CDC has great information on the tick diseases, and also on practical matters such as how to avoid getting bitten by a tick, and what to do once you have been bitten. You can even download a 21-page handbook: Tickborne Diseases of the United States.      

One small, small benefit from having survived an anaplasmosis infection is that if someone asks how you are, and you answer "I've been worse," you are telling the truth.

In addition to Lyme and Anaplasma, deer ticks may also transmit babesiosis (a parasite disease) and Powassan virus. Babesiosis is rarer than Anaplasma, and Powassan is extremely rare. Other diseases are transmitted by other tick species in other regions of the country. Visit the CDC website for details.

No comments:

Post a Comment