Ehrlichiosis
Ehrlichiosis | |
---|---|
The lone star tick, which is one of three ticks that can spread Ehrlichiosis. It is characterized by the white dot on its back.[1] | |
Specialty | Infectious diseases |
Symptoms | Fever, chills, severe headaches, muscle aches, nausea, vomiting, diarrhea, loss of appetite, confusion, and splotchy or pinpoint rash. More severe symptoms include brain or nervous system damage, respiratory failure, uncontrollable bleeding, organ failure, and death.[2] |
Causes | Bite from an infected tick |
Risk factors | Age, being immunocompromised, having received an organ transplant, and certain medications |
Ehrlichiosis is a tick-borne[3]
bacterial infection,
The average reported annual incidence is on the order of 2.3 cases per million people.[5]
Types
Six (see note below) species have been shown to cause human infection:[6]
- Anaplasma phagocytophilum causes Human granulocytic anaplasmosis. A. phagocytophilum is endemic to New England and the north-central and Pacific regions of the United States.
- human ewingii ehrlichiosis. E. ewingii primarily infects deer and dogs (see Ehrlichiosis (canine)).[5]E. ewingii is most common in the south-central and southeastern states.
- human monocytic ehrlichiosis. E. chaffeensis is most common in the south-central and southeastern states.
- Ehrlichia canis
- Neorickettsia sennetsu
- Ehrlichia muris eauclairensis[7]
The latter three infections are not well studied. Ehrlichia muris eauclairensis was recently discovered and has low reporting numbers due to the fact that it is relatively new and because its symptoms are very similar to the symptoms caused by other Ehrlichia bacteria.
In 2008, human infection by a
Ehrlichia species are transported between cells through the host-cell filopodia during the initial stages of infection; whereas, in the final stages of infection, the pathogen ruptures the host cell membrane.[11]
Signs and symptoms in humans
Specific symptoms include fever, chills, severe headaches, muscle aches, nausea, vomiting, diarrhea, loss of appetite, confusion, and a splotchy or pinpoint rash.
Most of the signs and symptoms of ehrlichiosis can likely be ascribed to the immune dysregulation that it causes.[
Experiments in mouse models further support this hypothesis, as mice lacking TNF-alpha I/II receptors are resistant to liver injury caused by Ehrlichia infection.[14]
About 3% of human monocytic ehrlichiosis cases result in death; however, these deaths occur "most commonly in immunosuppressed individuals who develop
Signs and symptoms in dogs
Ehrlichiosis in dogs will show obvious symptoms on the later part of infection. This is why some symptoms are already severe when diagnosed. There are three stages of ehrlichia infection - the acute (or the early stage), sub-clinical (symptoms are not yet evident), and clinical or chronic (symptoms are obvious and long-standing). [16]
Dogs infected with Ehrlichia often show lameness, lethargy, enlarged lymph nodes, and loss of appetite during the acute phase, which is one to three weeks after infection. Other symptoms include cough, diarrhea, vomiting, abnormal bruising and/or bleeding, fever, and loss of balance.[17]
Dogs with this disease can develop anemia which will show low platelet count which can eventually result to bleeding or blindness. Some doctors also check for arthritis-like symptoms, where the dogs cannot stand on one feet or more because of sore joints. Urinalysis may also be done to the dog to check if the kidneys were infected by the disease. [18]
Prevention
No human vaccine is available for ehrlichiosis. Tick control is the main preventive measure against the disease. However, in late 2012, a breakthrough in the prevention of canine monocytic ehrlichiosis was announced when a vaccine was accidentally discovered by Prof. Shimon Harrus, Dean of the Hebrew University of Jerusalem's Koret School of Veterinary Medicine.[19]
Measures of tick bite prevention include staying out of tall grassy areas that ticks tend to live in, treating clothes and gear that a tick could jump on, using EPA approved bug repellent, tick checks for all humans, animals, and gear that potentially came into contact with a tick, and showering soon after being in an area that ticks might also be in.[20]
Since prevention is the most advanced way of fighting the disease, the veterinarians advise dog owners to get rid of ticks and fleas by using products like Advantix®, Frontline Plus®, Vectra 3D® or Bravecto®. Oral chewable options include Nexgard®, Simparica®, Credelio®, or Bravecto®.[21]
Treatment
Since decline in platelets may also be evident in dogs with this disease, Eupherbia Hirta (Tawa-tawa in Philippines) can also be a supplemental treatment. This plant (or medicines which has this ingredient) helps with the increase of platelets.[22]
Epidemiology
Ehrlichiosis is a nationally notifiable disease in the United States. Cases have been reported in every month of the year, but most cases are reported during April–September.[23][24][25] These months are also the peak months for tick activity in the United States.[7] The majority of cases of Ehrlichiosis tend to be in the United States. The states affected most include "the southeastern and south-central United States, from the East Coast extending westward to Texas."[26]
Since the first case of Ehrlichiosis was reported in 2000, cases reported to the CDC have increased, for example, in 2000, 200 cases were reported and in 2019, 2,093 cases were reported. Fortunately, the "proportion of ehrlichiosis patients that died as a result of infection" has gone down since 2000.[27]
From 2008 to 2012, the average yearly incidence of ehrlichiosis was 3.2 cases per million persons. This is more than twice the estimated incidence for 2000–2007.[25] The incidence rate increases with age, with the ages of 60–69 years being the highest age-specific years. Children less than 10 years and adults aged 70 years and older have the highest case-fatality rates.[25] A documented higher risk of death exists among persons who are immunosuppressed.[23]
See also
References
- ^ CDC (2019-01-17). "Ehrlichiosis home | CDC". Centers for Disease Control and Prevention. Retrieved 2021-11-03.
- ^ CDC (2019-01-17). "Signs and symptoms of ehrlichiosis | CDC". Centers for Disease Control and Prevention. Retrieved 2021-11-03.
- ^ "Ehrlichiosis". Division of Vector-Borne Diseases (DVBD), National Center for Emerging and Zoonotic Infectious Diseases (NCEZID), Centers for Disease Control and Prevention. 15 November 2013.
- ISBN 1555811205.
- ^ a b c Goddard J (September 1, 2008). "What Is New With Ehrlichiosis?". Infections in Medicine.
- S2CID 25167899.
- ^ a b CDC (2021-08-04). "Ehrlichiosis epidemiology and statistics | CDC". Centers for Disease Control and Prevention. Retrieved 2021-11-03.
- ^ CDC (2021-08-04). "Ehrlichiosis epidemiology and statistics | CDC". Centers for Disease Control and Prevention. Retrieved 2021-12-02.
- PMID 18447934.
- ^ a b Steenhuysen J (3 August 2011). "New tick-borne bacterium found in upper Midwest". Reuters. Archived from the original on 2012-06-09.
- PMID 21187937.
- ISSN 2328-8957.
- PMID 7635455.
- PMID 21276277.
- PMID 19681699.
- ^ "Ehrlichiosis in Dogs | VCA Animal Hospitals". Vca. Retrieved 2023-11-03.
- ^ "Ehrlichiosis in Dogs". Pet MD. Retrieved 24 January 2023.
- ^ "Ehrlichiosis in Dogs | VCA Animal Hospitals". Vca. Retrieved 2023-11-03.
- PMID 23072894.
- ^ CDC (2020-07-01). "Preventing tick bites on people | CDC". Centers for Disease Control and Prevention. Retrieved 2021-12-02.
- PMID 27317101.
- ^ Sariego S. "TAWA TAWA LEAVES (Euphorbia hirta) SUPPLEMENTAL TABLET AS AN ALTERNATIVE TREATMENT FOR REDUCING HYPERCHOLESTEROLEMIA".
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(help) - ^ a b Dahlgren FS, Heitman KN, Drexler NA, Massung RF, Behravesh CB. "Human granulocytic anaplasmosis in the United States from 2008 to 2012: a summary of national surveillance data". Am J Trop Med Hyg 2015;93:66–72. Archived 2021-11-12 at archive.today
- PMID 26324732.
- ^ PMID 26621561.
- ^ CDC (2021-08-04). "Ehrlichiosis epidemiology and statistics | CDC". Centers for Disease Control and Prevention. Retrieved 2021-12-02.
- ^ CDC (2021-08-04). "Ehrlichiosis epidemiology and statistics | CDC". Centers for Disease Control and Prevention. Retrieved 2021-12-02.
External links
- Aayushi Pratap: Dog ticks may get more of a taste for human blood as the climate changes. On: ScienceNews. November 30, 2020.