Sodoku (鼠毒) is a bacterial
zoonotic disease. It is caused by the
Gram-negative
Gram-negative bacteria are bacteria that do not retain the crystal violet stain used in the Gram staining method of bacterial differentiation. They are characterized by their cell envelopes, which are composed of a thin peptidoglycan cell wa ...
rod ''
Spirillum minus'' (also known as ''Spirillum minor''). It is a form of
rat-bite fever (RBF).
Signs and symptoms
The initial scratch or wound caused by a bite from a carrier rodent results in mild inflammatory reactions and ulcerations. The wounds may heal initially, but reappear with the onset of symptoms. The symptoms include recurring
fever
Fever, also referred to as pyrexia, is defined as having a temperature above the normal range due to an increase in the body's temperature set point. There is not a single agreed-upon upper limit for normal temperature with sources using val ...
, with body temperature 101–104°F (38–40°C). The fever lasts for 2–4 days, but recurs generally at 4–8 weeks. This cycle may continue for months or years. The other symptoms include regional
lymphadenitis,
malaise, and
headache
Headache is the symptom of pain in the face, head, or neck. It can occur as a migraine, tension-type headache, or cluster headache. There is an increased risk of depression in those with severe headaches.
Headaches can occur as a resul ...
. The complications include
myocarditis
Myocarditis, also known as inflammatory cardiomyopathy, is an acquired cardiomyopathy due to inflammation of the heart muscle. Symptoms can include shortness of breath, chest pain, decreased ability to exercise, and an irregular heartbeat. The ...
,
endocarditis
Endocarditis is an inflammation of the inner layer of the heart, the endocardium. It usually involves the heart valves. Other structures that may be involved include the interventricular septum, the chordae tendineae, the mural endocardium, or the ...
,
hepatitis
Hepatitis is inflammation of the liver parenchyma, liver tissue. Some people or animals with hepatitis have no symptoms, whereas others develop yellow discoloration of the skin and whites of the eyes (jaundice), Anorexia (symptom), poor appetite ...
,
splenomegaly
Splenomegaly is an enlargement of the spleen. The spleen usually lies in the left upper quadrant (LUQ) of the human abdomen. Splenomegaly is one of the four cardinal signs of ''hypersplenism'' which include: some reduction in number of circulati ...
, and
meningitis
Meningitis is acute or chronic inflammation of the protective membranes covering the brain and spinal cord, collectively called the meninges. The most common symptoms are fever, headache, and neck stiffness. Other symptoms include confusion ...
.
Causes
The infections are acquired through
rat
Rats are various medium-sized, long-tailed rodents. Species of rats are found throughout the order Rodentia, but stereotypical rats are found in the genus ''Rattus''. Other rat genera include ''Neotoma'' ( pack rats), ''Bandicota'' (bandicoot ...
bites or scratches. It can occur as
nosocomial infections (i.e., acquired from hospitals), or due to exposure or close associations with animals preying on rats, mice, squirrels, etc. Sodoku is mostly seen in Asia and Africa. Local transmission has been reported in US.
The incubation period is 4 to 28 days.
Prognosis
Mortality is 6–10%.
References
External links
{{Gram-negative non-proteobacterial bacterial diseases
Zoonotic bacterial diseases