Approach Considerations
Notification of local and state public health departments and the Centers for Disease Control and Prevention (CDC) may provide resources for further epidemiologic investigation into the source of the infection.
Appropriate barrier precautions should remain in place throughout the hospital course because of the highly pathogenic nature of viral hemorrhagic fever infection and because various causes of viral hemorrhagic fever often are clinically indistinguishable.
Prehospital Care
Supportive care is based on the patient's physiologic condition. Because most patients requiring prehospital evaluation and transport are in the early stages of the disease, universal precautions should be adequate. In patients with respiratory symptoms (eg, cough, rhinitis), use face shields and high-efficiency particulate air (HEPA) filter masks.
Emergency Department Care
Fluid resuscitation and supportive care are the mainstays of emergency department therapy. Intravenous crystalloids, oxygen, and cardiac monitoring are the most appropriate initial steps in the treatment of patients in whom viral hemorrhagic fever (VHF) is suggested. Other measures include the following:
-
Administer blood and blood products as clinically indicated
-
Avoid intramuscular injections and the use of aspirin or other anticoagulants
-
Minimize invasive procedures because of the risk associated with viral transmission from sharp objects
-
Minimize aerosol-generating procedures such as bilevel positive airway pressure (biPAP), intubation, bronchoscopy and sputum induction.
Infection control measures include the following:
-
Place patients in a single-patient room with a private bathroom
-
Avoid entry of nonessential staff and visitors; facilities should maintain a log of all people entering the patient’s room
-
All staff entering the room should wear appropriate personal protective equipment (PPE); see below
PPE should include the following:
-
Impermeable garment
-
Respiratory protection (N95 mask with single-use surgical hood or single-use full face shield) or powered-air purifying respirator (PAPR) with full face shield or hood
-
Single-use examination gloves with extended cuffs
-
Single-use boot covers
-
Single-use apron (if patients have vomiting or diarrhea)
For donning of PPE, a trained observer should read aloud to the healthcare worker each step in the procedure checklist and visually confirm and document that the step has been performed correctly.
A separate area should be designated for donning and doffing of PPE. The space and layout must allow for clear separation between clean and contaminated areas
Note that these infection control recommendations were developed for use with patients with suspected or confirmed Ebola virus disease, but may also be used for any patient with suspected VHF infection. For more details, see the US Centers for Disease Control and Prevention's Ebola infection control recommendations.
Prevention
Because fruit bats have been shown to be natural reservoirs for Ebola and Marburg, [25] specific prevention measures should include avoidance of bats, their excreta, and areas with concentrated bat populations within endemic areas. Studies have suggested that contact with fruit bats may be responsible for some cases of filovirus infection. [26, 27]
An experimental Ebola vaccine, rVSV-ZEBOV, appears to offer substantial protection against Ebola virus disease. [28] An open-label, cluster-randomised trial evaluated vaccine effectiveness in case contacts, where clusters of contacts of Ebola cases were randomised for immediate or delayed vaccination.The authors estimated the vaccine efficacy to be 100% (95% CI 68·9–100, P=0.0045) in individuals vaccinated in the immediate group compared with those eligible and randomized to the delayed group. [29] However, the extent of this efficacy has been debated. [30]
Efforts are under way in West Africa to educate people in high-risk areas about ways to decrease rodent populations, thereby reducing transmission of Lassa fever.
Strict barrier precautions in the treatment of patients with known or suspected viral hemorrhagic fever infection reduce nosocomial transmission.
Proposed guidelines for the use of ribavirin for Lassa fever postexposure prophylaxis recommend the use of oral ribavirin exclusively for definitive, high-risk exposures, such as the following [31] :
-
Contaminated needlestick injury
-
Mucous membrane or nonintact skin exposure with contaminated blood or body fluids
-
Participation in emergency resuscitative procedures (eg, intubation, suctioning)
-
Prolonged close contact in an enclosed space with infected patients without appropriate personal protective equipment
-
Ebola virus. Electron micrograph courtesy of the Centers for Disease Control and Prevention.
-
Marburg virus. Negative stain image courtesy of the Centers for Disease Control and Prevention.
-
Mastomys rodent, natural host of Lassa virus. Image courtesy of the Centers for Disease Control and Prevention.
-
Bunyavirus infection. Ecchymoses encompassing left upper extremity one week after onset of CCHF. Ecchymoses often are accompanied by hemorrhage in other locations: epistaxis, puncture sites, hematemesis, melena, and hematuria. Image provided by Robert Swaneopoel, PhD, DTVM, MRCVS, National Institute of Virology, Sandringham, South Africa.
-
Apodemus agrarius, the vector of Korean hemorrhagic fever caused by a hantavirus. Photo courtesy of David McClain, MD.
-
Bunyavirus infection - Hantaan virus. Patient with Korean hemorrhagic fever caused by Hantaan virus demonstrating typical 'sunburn flush' of cheeks, chin, and base of neck. Photo courtesy of John Huggins, PhD.
-
Bunyavirus infection. A patient with Korean hemorrhagic fever demonstrating conjunctival hemorrhages, facial petechiae, and "sunburn flush" of the cheeks. Photo courtesy of John Huggins, PhD.
-
Filovirus disease - Ebola fever. Patient with Ebola hemorrhagic fever during 1976 outbreak in Zaire demonstrating palatal petechiae and hemorrhage. Photo courtesy of Joel Breman.
-
Patient with morbilliform exanthem of dengue fever. Note islands of sparing, which is characteristic for dengue. Photo courtesy Duane Gubler, PhD.
-
Patient with dengue hemorrhagic fever complicated by ecchymoses. Photo courtesy of Duane Gubler, PhD.
-
Dengue Virus Notice posted outside Maracanã Stadium, Rio de Janeiro, Brazil, 2012. Translation: This site is a strategic point for controlling Dengue.
-
Mastomys natalensis, natural host of Lassa virus. Photo courtesy of BioMed Central, originally published in Kelly JD, Barrie MB, Ross RA, Temple BA, Moses LM, Bausch DG. Housing equityfor health equity: a rights-based approach to the control of Lassa fever inpost-war Sierra Leone. BMC Int Health Hum Rights. 2013 Jan 2;13:2.
Tables
Virus Family |
Disease (Virus) |
Natural Distribution |
Usual Source of Human Infection |
Incubation (Days) |
Arenaviridae |
|
|
|
|
Arenavirus |
Lassa fever |
Africa |
Rodent |
5-16 |
|
Argentine HF (Junin) |
South America |
Rodent |
7-14 |
|
Bolivian HF (Machupo) |
South America |
Rodent |
9-15 |
|
Brazilian HF (Sabia) |
South America |
Rodent |
7-14 |
|
Venezuelan HF (Guanarito) |
South America |
Rodent |
7-14 |
Bunyaviridae |
|
|
|
|
Phlebovirus |
Rift Valley fever |
Africa |
Mosquito |
2-5 |
Nairovirus |
Crimean-Congo HF |
Europe, Asia, Africa |
Tick |
3-12 |
Hantavirus |
Hemorrhagic fever with renal syndrome, Hantavirus pulmonary syndrome |
Asia, Europe, worldwide |
Rodent |
9-35 |
Filoviridae |
|
|
|
|
Filovirus |
Marburg and Ebola |
Africa |
Fruit bat |
2-216 |
Flaviviridae |
|
|
|
|
Flavivirus |
Yellow fever |
Tropical Africa, South America |
Mosquito |
3-6 |
|
Dengue HF |
Asia, Americas, Africa |
Mosquito |
Unknown for dengue HF, 5-7 for dengue |
