All cases had a clinical presentation of encephalitis and were confirmed serologically. Clinically most cases presented with fever, meningitis syndrome with altered mental status. Tremors were common (56% of cases). There were three deaths. [ncbi.nlm.nih.gov]

The results of the present nonrandomized, unblinded, interventional pilot study of the use of IFN-α2b therapy for St. [doi.org]

• Fever

  /immunology West Nile Fever/transmission West Nile Fever/veterinary* West Nile Fever/virology West Nile virus/genetics* West Nile virus/immunology West Nile virus/physiology Substance Viral Nonstructural Proteins Grant support AI065359 /NH/NIH HHS/United [ncbi.nlm.nih.gov]

  People with mild illness often have only a headache and fever. [cdc.gov]

  The mild form of the disease results in fever and headaches. Serious cases of the illness include symptoms such as high fever, neck stiffness and persisting headaches. [mosquitonix.com]

  Laboratory Diagnosis The differential diagnosis of YF include typhoid, leptospirosis, tick-borne relapsing fever, typhus, Q fever, malaria, severe viral hepatitis, Rift valley fever, Crimean-Congo haemorrhagic fever, Lassa, Marburg and Ebola fever. [virology-online.com]

• High Fever

  Louis encephalitis infections produce mild symptoms that include fever and headache. In more severe cases, high fever, neck stiffness, disorientation, tremors, coma, and convulsions can occur. [valentbiosciences.com]

  Louis Encephalitis will have no symptoms or signs and never feel sick Mild Symptoms: Most of those who do have symptoms or signs will have a fever and headaches Severe Symptoms: Few of those infected have the severe symptoms such as high fever, severe [smcmvcd.org]

  Severe Symptoms: Headache High fever Neck stiffness Stupor Disorientation Coma Tremors Additional Resources: California Department of Public Health: St Louis Encephalitis Centers for Disease Control and Prevention: St Louis Encephalitis [shastamosquito.org]

  The mild form of the disease results in fever and headaches. Serious cases of the illness include symptoms such as high fever, neck stiffness and persisting headaches. [mosquitonix.com]

• Chills

  Symptomatology on admission included fever, chills, severe headache, abdominal pain, myalgia, arthralgia and jaundice. SLE virus was isolated from her blood drawn on the 8th day of illness and subsequent seroconversion was documented. [ncbi.nlm.nih.gov]

  Disease onset is characterized by generalized malaise, fever, chills, headache, drowsiness, nausea, and sore throat or cough followed in 1 to 4 days by meningeal and neurologic signs. [mayocliniclabs.com]

  Clinical Features The incubation period varies from 3 to 6 days, following which there is an abrupt onset of chills, fever, and headache. [virology-online.com]

• Rigor

  Common symptoms were fever, rigors, diarrhea, headache, and confusion. One patient died 3 days after hospitalization. [ncbi.nlm.nih.gov]

  %/protein/Gluc Treatment 69/m Kidney 7/28/2015 9/2/2015 Survived 27/14%/50/86 INF+IVIG 67/m Kidney 12/13/2013 7/24/2015 Died 102/36%/108/54 None 57/m Kidney/heart 10/6/2012 7/2/2105 Survived 84/16%/114/58 INF+IVIG Most common symptoms: fever (3/3), rigors [atcmeetingabstracts.com]

  Epidemiology United States statistics Determining the true incidence of encephalitis is impossible, because reporting policies are neither standardized nor rigorously enforced. [emedicine.medscape.com]

• Nausea

  Initial symptoms of those who become ill include fever, headache, nausea, vomiting, and tiredness. Severe neuroinvasive disease (often involving encephalitis, an inflammation of the brain) occurs more commonly in older adults. [tn.gov]

  […] by a virus of the Flaviviridae family transmitted by an infected mosquito, and characterized by the onset of flulike symptoms such as fever, malaise, headache, cough, and sore throat that can progress to meningitis or encephalitis with symptoms like nausea [orpha.net]

  Symptoms of illness include fever, headache, nausea, vomiting, and tiredness. Some people may have neuroinvasive disease that often involves encephalitis, an inflammation of the brain. Arboviral diseases home Last Revised: May 13, 2019 [dhs.wisconsin.gov]

  Signs and symptoms include the sudden onset of drowsiness, headache and nausea (due to the encephalitis), pain in the abdomen, a rash, and swollen glands (lymphadenopathy). These features are usually but not always mild. [medicinenet.com]

• Vomiting

  Initial symptoms of those who become ill include fever, headache, nausea, vomiting, and tiredness. Severe neuroinvasive disease (often involving encephalitis, an inflammation of the brain) occurs more commonly in older adults. [tn.gov]

  […] virus of the Flaviviridae family transmitted by an infected mosquito, and characterized by the onset of flulike symptoms such as fever, malaise, headache, cough, and sore throat that can progress to meningitis or encephalitis with symptoms like nausea, vomiting [orpha.net]

  Symptoms of illness include fever, headache, nausea, vomiting, and tiredness. Some people may have neuroinvasive disease that often involves encephalitis, an inflammation of the brain. Arboviral diseases home Last Revised: May 13, 2019 [dhs.wisconsin.gov]

  Louis encephalitis-infected mosquito do not become ill, but those who do will experience symptoms such as fever, headache, nausea, vomiting and fatigue. [latimes.com]

• Hypertension

  Hypertension and vascular disease may predispose to neuroinvasive disease, but this epidemiologic study has not ruled out the confounding effects of age. [ncbi.nlm.nih.gov]

  Male sex is a risk factor Most SLEV infection outbreaks occur in people of low socioeconomic status, which is probably due to less access to heath care and poor environmental control of mosquitoes Comorbidity with atherosclerosis, heart disease, and hypertension [emedicine.medscape.com]

• Photophobia

  Photophobia, cranial nerve palsies, and even coma may occur. [orpha.net]

  Photophobia is seldom present. The neurologic examination findings are usually normal. Five percent of patients with SLEV infection present with deep coma, and 25% develop cranial nerve palsies. Fewer exhibit ataxia. [emedicine.medscape.com]

  During the evolution he added: mental confusion, photophobia, inability to recognize parents or medical staff, obey simple commands, and arterial hypertension. 6 days after he spontaneously improved. IgM for St. [scienceopen.com]

• Diplopia

  Additional signs noted at, or after, admission to the hospital were nystagmus, diplopia, ophthalmoplegia, respiratory insufficiency, tremor, ataxia, peripheral weakness, confusion, or decreased level of consciousness. [doi.org]

• Dysuria

  Illness is classified into 3 syndromes: Constitutional symptoms, fever, headache, myalgia, cough, sore throat, dysuria, urinary urgency Aseptic meningitis Fatal encephalitis Symptoms: Asymptomatic in the vast majority (>99%) Malaise, fever, headache, [visualdx.com]

  […] encephalitis include the following: Encephalitis caused by varicella-zoster virus (VZV), Epstein-Barr virus (EBV), cytomegalovirus (CMV), measles virus, or mumps virus: Rash, lymphadenopathy, hepatosplenomegaly, and parotid enlargement St Louis encephalitis: Dysuria [emedicine.medscape.com]

• Headache

  headaches, coma, tremors, convulsions, paralysis, and possible death Is St. [smcmvcd.org]

  People with mild illness often have only a headache and fever. [cdc.gov]

  STUDY DESIGN: From January to May 2005, patients with symptoms of encephalitis, meningitis, or fever with severe headache were evaluated and an etiologic diagnosis achieved by detection of flavivirus-specific antibody sera and cerebrospinal fluid. [ncbi.nlm.nih.gov]

  Illness is classified into 3 syndromes: Constitutional symptoms, fever, headache, myalgia, cough, sore throat, dysuria, urinary urgency Aseptic meningitis Fatal encephalitis Symptoms: Asymptomatic in the vast majority (>99%) Malaise, fever, headache, [visualdx.com]

• Confusion

  tremors, clumsiness, and ataxia Confusion, delirium or somnolence with weakness, seizures Occasionally, tremulousness with cerebellar and cranial nerve deficits Neurologic and psychologic sequelae are not uncommon Hematuria Incubation period is 4-21 [visualdx.com]

  Common symptoms were fever, rigors, diarrhea, headache, and confusion. One patient died 3 days after hospitalization. [ncbi.nlm.nih.gov]

  Flaviviridae family transmitted by an infected mosquito, and characterized by the onset of flulike symptoms such as fever, malaise, headache, cough, and sore throat that can progress to meningitis or encephalitis with symptoms like nausea, vomiting, confusion [orpha.net]

• Seizure

  Evaluate the patient's neurologic status; check level of consciousness (LOC); observe and document evidence of seizure activity; institute seizure precautions, as appropriate. [quizlet.com]

  Louis encephalitis in a 19-day-old infant who presented with fever and seizure activity. To our knowledge, this is the youngest case of St. Louis encephalitis ever reported. [ncbi.nlm.nih.gov]

  As indicated in previous reports, 1, 3 prognosis was worse among patients with seizures. Of 4 patients with seizures, 2 died and 2 had a prolonged hospital course. [jamanetwork.com]

  This leads to changes in a child's nervous system that can include confusion, changes in alertness, and seizures. Meningitis often happens at the same time as encephalitis. [stlouischildrens.org]

• Irritability

  […] infected mosquito, and characterized by the onset of flulike symptoms such as fever, malaise, headache, cough, and sore throat that can progress to meningitis or encephalitis with symptoms like nausea, vomiting, confusion, stiff neck, disorientation, irritability [orpha.net]

  Other symptoms include fever, nausea, stiff neck/back, light sensitivity, confusion, drowsiness, irritability, and motor skill impairment. Wild bird populations are central to the transmission cycle. [amcdsjc.org]

  Symptoms of irritability, sleeplessness, depression, memory loss, and headaches can last up to 3 years. Infections with arboviruses, including SLE, can occur at any age. [mayocliniclabs.com]

  Do not apply insect repellent to a child’s hands, eyes, mouth, cuts, or irritated skin. Adults: Spray insect repellent onto your hands and then apply to a child’s face. Tips for Everyone Always follow the product label instructions. [cdc.gov]

• Neck Stiffness

  In more severe cases, high fever, neck stiffness, disorientation, tremors, coma, and convulsions can occur. Fatality rates range from 5%–30%, with the elderly more likely to suffer fatal infections.* [valentbiosciences.com]

  Severe Symptoms: Headache High fever Neck stiffness Stupor Disorientation Coma Tremors Additional Resources: California Department of Public Health: St Louis Encephalitis Centers for Disease Control and Prevention: St Louis Encephalitis [shastamosquito.org]

  Clonus and neck stiffness were detected at physical exam. Cerebrospinal fluid revealed mononuclear leukocytosis; bilateral ischemic compromise was observed in thalamus by magnetic resonance. [ncbi.nlm.nih.gov]

  More severe disease is marked by fever, headache, neck stiffness, stupor, disorientation, coma, tremors, occasional convulsions (especially in infants) and spastic (but rarely flaccid) paralysis. [cdc.gov]

  Serious cases of the illness include symptoms such as high fever, neck stiffness and persisting headaches. As the disease progresses, infected people may develop tremors, convulsions, stupor, disorientation and spastic paralysis. [mosquitonix.com]

Technical Appendix: Additional description of diagnostic workup and methods used in study of fatal human case of St. Louis encephalitis virus infection. [ncbi.nlm.nih.gov]

See Workup for more detail. [emedicine.medscape.com]

• Periodic Lateralized Epileptiform Discharges

  Electroencephalograms were obtained for 9 patients and results on all were abnormal, showing status epilepticus (1 patient) ( Figure 1 ), bilateral periodic lateralized epileptiform discharges (1 patient), and background diffuse slowing (7 patients). [jamanetwork.com]

• Hyponatremia

  Of this group, 13 patients appeared to have hyponatremia due to inappropriate secretion of antidiuretic hormone; the remaining patients were probably hyponatremic from salt depletion. [annals.org]

  The medical literature also contains reports of syndrome of inappropriate antidiuretic hormone secretion (SIADH) and hyponatremia in patients with St. [emedicine.medscape.com]

  In patients who develop neurologic disease about 30% will also develop hyponatremia and fluid overload due to inappropriate secretion of antidiuretic hormone (SIADH).[7][8][9] Electroencephalography (EEG) may show diffuse slowing and delta-wave activity [ncbi.nlm.nih.gov]

• Neutrophil Count Decreased

  Absolute neutrophil counts decreased to 3 in 3 patients (all 3 had counts of 900– 1000 neutrophils/mm 3 ), and the counts recovered to >1000 neutrophils/mm 3 after IFN-α2b therapy was withheld temporarily. No secondary bacterial infections occurred. [doi.org]

• Hypocapnia

  In two of the conscious patients cerebral blood flow was normal despite normal arterial oxygen tension and systemic hypocapnia; inflammatory cerebral vasodilatation may have accounted for the findings. [annals.org]

Treatment significantly reduced the levels of viral RNA in the serum, brain, and spleen [ 8 ]. [doi.org]

There is currently no therapeutic treatment for SLE. Current methods consist primarily of symptom treatment and supportive care. Many SLE epidemics have been documented in North America. In 1990, there were 223 cases in Florida. [floridahealth.gov]

The main treatment for this encephalitis is treatment of symptoms, because there is no vaccine or specific treatment just for this disease. [insectcop.net]

The EEG proved valuable in diagnosis and prognosis. Results of brain scans were normal. Virus in CSF or urine was not demonstrated, nor was viral antigen in CSF or urine sediments. [archinte.jamanetwork.com]

Prognosis The mortality rate of St. Louis encephalitis is 2-30%. This figure is higher in older patients. [7] Of persons who survive St. [emedicine.medscape.com]

Louis encephalitis virus (SLEV) as the etiologic agent. [ncbi.nlm.nih.gov]

Etiology and Pathophysiology St. Louis encephalitis is caused by an enveloped, single-stranded, positive-sense ribonucleic acid (RNA) virus of the Flaviviridae subgroup. St. [emedicine.medscape.com]

Louis Encephalitis Tree Number: B04.820.230.475.330 B04.820.250.350.300.330 Definition English: A species of FLAVIVIRUS, one of the Japanese encephalitis virus group (ENCEPHALITIS VIRUSES, JAPANESE), which is the etiologic agent of ST. [decs.bvs.br]

Louis/epidemiology* Encephalitis, St. Louis/history Encephalitis, St. Louis/transmission Encephalitis, St. [ncbi.nlm.nih.gov]

Etiology and Pathophysiology St. Louis encephalitis is caused by an enveloped, single-stranded, positive-sense ribonucleic acid (RNA) virus of the Flaviviridae subgroup. St. [emedicine.medscape.com]

Abstract Studies of pathophysiology in epidemic St. Louis encephalitis were undertaken during the 1966 Dallas epidemic. Eighteen of 52 patients were hyponatremic during their acute illness. [annals.org]

Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test Since 1933, outbreaks of St. [mayocliniclabs.com]

Few mosquitoes actually carry the virus, but it is important to take prevention measures when spending time outside. St. Louis encephalitis is preventable. Visit our Mosquito Bite Prevention page to learn how to prevent mosquito bites. [dhs.wisconsin.gov]

Prevention The best way to prevent SLEV disease is to avoid mosquito bites. Please see our mosquito prevention page for more information. For more information about St. Louis encephalitis virus, visit the CDC SLEV webpage. [in.gov]

Severe illnesses are treated by supportive therapy which may include hospitalization, respiratory support, intravenous (IV) fluids, and prevention of other infections. How can St. Louis encephalitis be prevented? Prevent mosquito bites. [vdh.virginia.gov]

There are no effective antiviral drugs, and there is currently no vaccine available to prevent infection. Since there is no adequate treatment or vaccine, prevention is critical. Prevention is best accomplished by avoiding mosquito bites entirely. [ncbi.nlm.nih.gov]