Human infection results most commonly from exposure to dust or food contaminated by the gray house mouse or hamsters, which harbor the virus and excrete it in urine, feces, semen, and nasal secretions. When transmitted by mice, the disease occurs primarily in adults during autumn and winter.
Most patients have no or minimal symptoms. Some develop a flu-like illness. Fever, usually Sore throat and dysesthesia occur less often. After 5 days to 3 weeks, patients may improve for 1 or 2 days. Many relapse with recurrent fever, headache, rashes, swelling of metacarpophalangeal and proximal interphalangeal joints, meningeal signs, orchitis, parotitis, or alopecia of the scalp. Aseptic meningitis Overview of Meningitis Meningitis is inflammation of the meninges and subarachnoid space.
It may result from infections, other disorders, or reactions to drugs. Severity and acuity vary. Findings typically include Rarely, frank encephalitis, ascending paralysis, bulbar paralysis, transverse myelitis, or other neurologic symptoms can occur. Infection during pregnancy may cause fetal abnormalities, including hydrocephalus, chorioretinitis, and intellectual disability. Infections that occur during the 1st trimester may result in fetal death. Polymerase chain reaction PCR , cerebrospinal fluid analysis, antibody detection, and viral culture.
Lymphocytic choriomeningitis is suspected in patients with exposure to rodents and an acute illness, particularly aseptic meningitis or encephalitis. We report of a case of LCMV meningitis in a laboratory worker who sustained a penetrating needlestick injury with a LCMV-contaminated hollow needle whilst disposing of a used syringe into the sharps waste bin. It highlights the importance of infection prevention practices that comprise particularly well established safety precaution protocols in research laboratories handling this pathogenic virus, because exposure to even a small amount of LCMV can lead to a severe, life-threatening infection.
LCMV infection is usually asymptomatic or mild and self-limiting, but rarely can manifest itself as severe disease such as meningitis and encephalitis [ 1 ]. In organ transplant recipients and immunocompromised patients such an infection can be life-threatening [ 2 , 3 ]. Congenital infections can result in life-long mental retardation and vision deficits [ 4 ]. Modes of transmission to humans are bites of infected mice, inhalation of aerosolized droplets of contaminated body fluids or inoculation of contaminated materials into broken skin, the eyes or the mouth [ 5 ].
There is no evidence-based standard drug available for post-exposure prophylaxis: Therefore, prevention of stab wounds with contaminated sharp objects, bite of infected mice and inhalation of contagious droplets, is indispensable to protect laboratory worker from occupational severe infection, leading even to epidemics [ 7 ].
This highlights the importance of infect prevention strategies that comprise particularly well established safety precaution protocols in research laboratories handling this pathogenic virus, because exposure to LCMV can lead to a life-threatening infection.
In May , a young scientist accidently sustained a penetrating needlestick injury to the left index finger from a LCMV-contaminated needle, whilst disposing of a used syringe in a correct manner into the inaccurate overfilled sharps waste bin. The needle stuck on a syringe that was used to infect mice with Lymphocytic choriomeningitis virus LCMV variant clone Following strictly the laboratory safety protocol, first aid measures were taken immediately after the injury by washing and disinfecting the wound.
A check-up at the university emergency room ER the same day, with clinical examination and blood tests remained unremarkable. As there is no known well-established medicamentous post-exposure prophylaxis, the patient was discharged and was advised to return to the ER if any signs of illness occur.
Four days after needlestick injury, she developed systemic illness, comprising acute severe lower back pain and fatigue Fig. Clinical presentation, symptoms and serological tests over the course of time since the day of needlestick injury Day 0.
CNS-symptoms include meningismus, photophobia, nausea and vomiting. ER: emergency room. Seven days after exposure, her clinical situation deteriorated by developing flu-like illness with cough, pharyngitis, neck pain, fever up to She presented to the ER where physical examination revealed no signs of meningitis or focal neurological deficits. Blood tests showed acute leukopenia 2.
She was discharged with symptomatic, pain-relieving therapy. Nine days after needlestick injury, symptoms of systemic illness, especially headaches and back pain, relapsed and worsened over time. She was admitted to the hospital where supportive care measures - rehydration and intensified pain relief - were established.
Cerebrospinal fluid CSF showed cell count in the normal range as well as protein, glucose and lactate level. Serological tests were reactive for tick-borne-encephalitis IgG and IgM positive consistent with her known positive vaccine status.
A multiplex polymerase chain reaction PCR performed in the CSF, including six bacterial species, seven viruses and one yeast, remained negative. MRI of the lumbar spine and the brain showed no evidence for abscess or meningeal enhancement. Serological testing was performed in Hamburg by immunofluorescence assays using LCMV-infected cells as antigen.
Figure 1. Diagnosis of acute LCMV meningitis after needlestick injury was based on epidemiological links and exposure, clinical signs and symptoms, seroconversion in plasma and detection of virus RNA in blood plasma by PCR. A diagnostic work-up at the clinic of neurology did not find any evidence for an alternative diagnosis. Modes of transmission to humans are bites of infected rodents, inhalation of aerosolized droplets of contaminated body fluids or inoculation of contaminated materials into broken skin, the eyes or the mouth [ 5 ].
LCMV infection is usually asymptomatic or mild and self-limiting, but rarely can manifest itself as meningitis and encephalitis [ 1 ]. In organ transplant recipients and immunocompromised patients, such infections can be life-threatening [ 2 , 3 ]. The initial phase begins with fever, malaise, muscle aches, headache and nausea and is lasting for about one week [ 10 ].
After a few days of recovery signs of meningoencephalitis occur [ 10 ]. Our patient developed this typical biphasic illness, though it already occurred four days after exposure. The cause of the shorter incubation period is most likely the high inoculum with which the patient has become infected and the mode of transmission via direct inoculation in the skin. It is of note that even in patients presenting with signs and symptoms of meningitis, CSF cell count still can be in the normal range as well as protein, glucose and lactate level.
A previous case report of iatrogenic LCMV infection was based on indirect evidence by serological tests, not direct virus detection by PCR, although the inoculum was presumably significantly higher than in our case [ 6 ]. There is no evidence-based standard drug available for post-exposure prophylaxis. No chronic infection has been described in humans, and after the acute phase of illness, the virus is cleared from the body. However, as in all infections of the central nervous system, particularly encephalitis, temporary or permanent neurological damage is possible.
Nerve deafness and arthritis have been reported. Women who become infected with LCMV during pregnancy may pass the infection on to the fetus.
Infections occurring during the first trimester may result in fetal death and pregnancy termination, while in the second and third trimesters, birth defects can develop. Infants infected In utero can have many serious and permanent birth defects, including vision problems, mental retardation, and hydrocephaly water on the brain. Pregnant women may recall a flu-like illness during pregnancy, or may not recall any illness.
Lymphocytic Choriomeningitis LCM. Section Navigation.
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