Hantavirosis
Overview
Infection by hantavirus which is a virus from the family Bunyaviridae. Infection generally causes severe febrile illness which can involve bleeding, shock and even death in some cases. The disease is transmitted by infected rodents.
Symptoms
* Hemorrhagic fever * Pneumonia * Fever * Headache * Maliase * Diarrhea * Nausea * Vomiting * Abdominal pain * Myalgia * Muscle ache * Backache * Rapid heart rate * Hypoxemia * Breathing difficulty * Low blood pressure * Kidney insufficiency * Protein in the urine * Bleeding * Petechiae * Bruises * Low blood pressure * Gastrointestinal bleeding * Bleeding from the nose * Bleeding from the mouth * Bleeding from the uterus * Icterus * Encephalitis * Retinitis
Causes
A member of the Bunyaviridae family, the genus Hantavirus (first isolated in 1977) is responsible for Hantavirus pulmonary syndrome. Disease transmission is associated with exposure to aerosols (such as dust) contaminated by urine or feces from infected rodents, the primary reservoir for this virus. Data suggest that the deer mouse is the main source, but pinon mice, brush mice, and western chipmunks in close proximity to humans in rural areas are also sources. Hantavirus infections have been documented in people whose activities are associated with rodent contact, such as farming, hiking or camping in rodent-infested areas, and occupying rodent-infested dwellings. Infected rodents manifest no apparent illness but shed the virus in feces, urine, and saliva. Human infection may occur from inhalation, ingestion (of contaminated food or water, for example), contact with rodent excrement, or rodent bites. Transmission from person to person or by mosquitoes, fleas, or other arthropods hasn’t been reported.
Diagnosis
Accurate assessment helps identify infectious diseases and prevents avoidable complications. Complete assessment consists of patient history, physical examination, and laboratory data. The history should include the patient's sex, age, address, occupation, and place of work; known exposure to illness and recent medications, including antibiotics; and date of disease onset. Signs and symptoms, including their duration and whether they occurred suddenly or gradually, should be included in the history as well as precipitating factors, relief measures, and weight loss or gain. Detail information about recent hospitalization; blood transfusions; blood donation denial by the Red Cross or other agencies; recent travel or camping trips; exposure to animals; and vaccinations. (See Immunization schedule.) If applicable, ask about possible exposure to sexually transmitted diseases or about drug abuse. Also, try to determine the patient's resistance to infectious disease. Ask about usual dietary patterns, unusual fatigue, and any conditions, such as neoplastic disease or alcoholism, that may predispose him to infection. Notice if the patient is listless or uneasy, lacks concentration, or has any obvious abnormality of mood or affect.
Treatment
Primarily supportive, treatment consists of maintaining adequate oxygenation, monitoring vital signs, and intervening to stabilize the patient's heart rate and blood pressure. Drug therapy includes vasopressors, such as dopamine or epinephrine, for hypotension. Fluid volume replacement may also be ordered (with precautions not to overhydrate the patient). Ribavirin in aerosol form has been used for children, but its efficacy for adults has not been proven.