Published Date: 2013-06-19 19:53:35
Subject: PRO/AH/EDR> Q fever - Brazil (02) (MG) NOT
Archive Number: 20130619.1782145
Q FEVER - BRAZIL (02) (MINAS GERAIS), NOT
*****************************************
A ProMED-mail post
http://www.promedmail.org
ProMED-mail is a program of the
International Society for Infectious Diseases
http://www.isid.org
Date: Tues 18 Jun 2013
From: Antonio Toledo <antonio.toledo@infectologia.org.br> [in Portuguese, machine trans., edited]
A team of infectious diseases specialists from the State Department of Health of Minas Gerais evaluated the cases of suspected Q fever.
None of the cases fulfilled the clinical criteria for acute or chronic Q fever (based on CDC diagnostic criteria) [see http://www.cdc.gov/mmwr/preview/mmwrhtml/rr6203a1.htm] and no epidemiologic linkage was identified.
In addition, 75 patients have negative Phase II serology (IFI/IFA) and of the 6 whose 1st test was positive, 5 had a negative 2nd test and one refused further testing because they were asymptomatic.
It should be noted that most of the cases were treated in the same health unit and were reported by a single health professional. No other medical unit had suspected cases of the disease.
It should also be noted that most of the suspected cases reported in 2013 were treated during a dengue outbreak [see ProMED-mail post Dengue/DHF update (39): Americas 20130521.1725995], which has the same clinical picture as Q fever.
--
Antonio Toledo via ProMED-PORT
Infectious Diseases Physician
<antonio.toledo@infectologia.org.br>
[The above correspondence from Dr. Antonio Toledo is a follow-up to ProMED-PORT post Febre Q - Brasil (02) (MG), casos sob investigacao, informacoes complementares 20130618.1780669 that was also reported by ProMED-mail post Q fever - Brazil: (MG) 20130617.1777459.
_Coxiella burnetii_, an obligate intracellular rickettsia-like bacterial pathogen causes Q fever. _C. burnetii_ is highly resistant to drying and heat, which is attributed to a small cell variant of the organism that is part of a biphasic developmental cycle. Domestic ungulates such as sheep, cattle, and goats serve as the reservoir of infection for humans.
Humans usually become infected by inhaling aerosolized organisms that are shed in urine, feces, milk, and especially birthing products; intermittent high-level shedding occurs at the time of parturition, with millions of bacteria being released per gram of placenta. Acute symptoms of a flu-like illness with hepatitis or pneumonia usually develop within 2-3 weeks after exposure, although as many as half of humans infected with _C. burnetii_ do not show symptoms (http://www.cdc.gov/qfever/symptoms/index.html). Although most persons with acute Q fever recover, others may experience serious chronic illness within a few months or several years after acute infection, with complications that include endocarditis (especially in patients with previous cardiac valvulopathy), infected aneurysms or vascular prostheses, and chronic hepatitis.
Q fever is primarily an occupational hazard for farmers, veterinarians, and abattoir workers in contact with infected domestic animals such as cattle, sheep, and goats and for laboratory personnel performing _C. burnetii_ cultures and working with _C. burnetii_-infected animals (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC88923/). Sporadic cases can also occur in people living in urban areas that are downstream from farms or abattoirs where the organisms have become aerosolized.
The acute and chronic stages of infection correspond to 2 distinct antigenic phases of antibody response. During an acute infection, an antibody response to _C. burnetii_ phase II antigen is predominant and is higher than the response to the phase I antigen, whereas chronic infection is associated with a rising phase I immunoglobulin G (IgG) titer.
The CDC has recently issued recommendations for the recognition, clinical and laboratory diagnosis, treatment, and management of Q fever (Morbidity and Mortality Weekly Report (MMWR). Diagnosis and Management of Q Fever -- United States, 2013: Recommendations from CDC and the Q Fever Working Group. Recommendations and Reports. 29 Mar 2013/62(RR03); 1-23. Available at http://www.cdc.gov/mmwr/preview/mmwrhtml/rr6203a1.htm). - Mod.ML
Subject: PRO/AH/EDR> Q fever - Brazil (02) (MG) NOT
Archive Number: 20130619.1782145
Q FEVER - BRAZIL (02) (MINAS GERAIS), NOT
*****************************************
A ProMED-mail post
http://www.promedmail.org
ProMED-mail is a program of the
International Society for Infectious Diseases
http://www.isid.org
Date: Tues 18 Jun 2013
From: Antonio Toledo <antonio.toledo@infectologia.org.br> [in Portuguese, machine trans., edited]
A team of infectious diseases specialists from the State Department of Health of Minas Gerais evaluated the cases of suspected Q fever.
None of the cases fulfilled the clinical criteria for acute or chronic Q fever (based on CDC diagnostic criteria) [see http://www.cdc.gov/mmwr/preview/mmwrhtml/rr6203a1.htm] and no epidemiologic linkage was identified.
In addition, 75 patients have negative Phase II serology (IFI/IFA) and of the 6 whose 1st test was positive, 5 had a negative 2nd test and one refused further testing because they were asymptomatic.
It should be noted that most of the cases were treated in the same health unit and were reported by a single health professional. No other medical unit had suspected cases of the disease.
It should also be noted that most of the suspected cases reported in 2013 were treated during a dengue outbreak [see ProMED-mail post Dengue/DHF update (39): Americas 20130521.1725995], which has the same clinical picture as Q fever.
--
Antonio Toledo via ProMED-PORT
Infectious Diseases Physician
<antonio.toledo@infectologia.org.br>
[The above correspondence from Dr. Antonio Toledo is a follow-up to ProMED-PORT post Febre Q - Brasil (02) (MG), casos sob investigacao, informacoes complementares 20130618.1780669 that was also reported by ProMED-mail post Q fever - Brazil: (MG) 20130617.1777459.
_Coxiella burnetii_, an obligate intracellular rickettsia-like bacterial pathogen causes Q fever. _C. burnetii_ is highly resistant to drying and heat, which is attributed to a small cell variant of the organism that is part of a biphasic developmental cycle. Domestic ungulates such as sheep, cattle, and goats serve as the reservoir of infection for humans.
Humans usually become infected by inhaling aerosolized organisms that are shed in urine, feces, milk, and especially birthing products; intermittent high-level shedding occurs at the time of parturition, with millions of bacteria being released per gram of placenta. Acute symptoms of a flu-like illness with hepatitis or pneumonia usually develop within 2-3 weeks after exposure, although as many as half of humans infected with _C. burnetii_ do not show symptoms (http://www.cdc.gov/qfever/symptoms/index.html). Although most persons with acute Q fever recover, others may experience serious chronic illness within a few months or several years after acute infection, with complications that include endocarditis (especially in patients with previous cardiac valvulopathy), infected aneurysms or vascular prostheses, and chronic hepatitis.
Q fever is primarily an occupational hazard for farmers, veterinarians, and abattoir workers in contact with infected domestic animals such as cattle, sheep, and goats and for laboratory personnel performing _C. burnetii_ cultures and working with _C. burnetii_-infected animals (http://www.ncbi.nlm.nih.gov/pmc/articles/PMC88923/). Sporadic cases can also occur in people living in urban areas that are downstream from farms or abattoirs where the organisms have become aerosolized.
The acute and chronic stages of infection correspond to 2 distinct antigenic phases of antibody response. During an acute infection, an antibody response to _C. burnetii_ phase II antigen is predominant and is higher than the response to the phase I antigen, whereas chronic infection is associated with a rising phase I immunoglobulin G (IgG) titer.
The CDC has recently issued recommendations for the recognition, clinical and laboratory diagnosis, treatment, and management of Q fever (Morbidity and Mortality Weekly Report (MMWR). Diagnosis and Management of Q Fever -- United States, 2013: Recommendations from CDC and the Q Fever Working Group. Recommendations and Reports. 29 Mar 2013/62(RR03); 1-23. Available at http://www.cdc.gov/mmwr/preview/mmwrhtml/rr6203a1.htm). - Mod.ML