‘Rat-bite fever’ cases reported in several Washington State residents
Chelan and Douglas County health officials are reporting the confirmation of a “few” cases of rat-bite fever in a few Chelan and Douglas County residents and possibly in a Grant County resident who may have been exposed there, according to a Chelan-Douglas Health District press release.
Image/National Park Service
“Rat-bite fever” is a general term to describe two relatively rare bacterial infections: Streptobacillus moniliformis, also known as Haverhill fever, and Spirillum minor, also known as Sodoku.
Both bacteria are normal or commensal organisms found in rats and to a lesser extent other rodents and mammals.
These infections are found worldwide, but seen most commonly in Asia and Africa.
The bacteria are found in the oral and nasal secretions of the infected rat. It can also be found in the rat’s urine.
Transmission to people is most frequently the result of a rat bite; however, direct contact with the rats is not always necessary. People who work or live in rat-infested buildings are also at risk and it has been transmitted through contaminated water and milk.
After about a week after being exposed, there is an abrupt onset of chills, fever, headache and muscle pains.
With S. moniliformis, a rash on the extremities appears after a few days. Arthritic symptomsmay also be present.
On the other hand, with S. minor, an ulcerated lesion at the bite site is typical andsymptoms of arthritis are rare.
Untreated cases can be fatal in up to 10% of cases. Endocarditis, pericarditis andabscesses of the brain are complications of untreated rat-bite fever.
Diagnosis of S. moniliformis can be confirmed through culture of primary lesion, blood, lymph node or joint fluid on specialized media. S. minor has not been cultured on artificial media and animal inoculation is required.
Penicillin or tetracycline can be used to treat the infection.
If you have had contact with rodents or other animals that have contact with rodents, and you have symptoms of the illness, see your medical provider. Health Districts in Chelan, Douglas and Grant Counties have made the health care community aware of this illness and asked them to monitor clients for more suspect cases of rat bite fever, a relatively rare disease.
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