Doctors warned to watch for Ebola and hantavirus as flu-like symptoms emerge
CMAJ reviews say early fever and muscle pain can mask two infections that may require rapid testing, isolation and supportive care.
By Tom Brennan · Health & Medicine Correspondent
3 min read
Two new reviews in the Canadian Medical Association Journal urge clinicians to move quickly when patients with possible exposure develop symptoms that can resemble a routine viral illness. CMAJ says Ebola virus disease and hantavirus differ in how they spread and whom they affect, but both can escalate quickly and require strict infection prevention and control measures.
The journal published separate clinical summaries on Ebola virus disease and hantavirus for health-care professionals. According to CMAJ, early signs can include fever, muscle pain, headache, fatigue or gastrointestinal symptoms, which can make exposure history and rapid testing central to identifying higher-risk cases.
Hantavirus risk and symptoms
CMAJ says hantavirus is a nationally reportable disease in Canada, with about four to five confirmed cases reported to public health authorities each year. Most Canadian infections follow rodent exposure in agricultural areas of Manitoba, Saskatchewan, Alberta and British Columbia, according to the journal.
Different hantavirus strains cause different illnesses, CMAJ says. In North and South America, including infections involving the Andes virus, hantavirus can cause cardiopulmonary syndrome; in Europe and Asia, hantaviruses are more often linked to hemorrhagic fever and kidney dysfunction.
The incubation period for both forms is usually two to four weeks, according to CMAJ. Common symptoms include fever, headache, muscle aches and abdominal pain.
CMAJ says diagnosis relies on serology and polymerase chain reaction testing carried out by the National Microbiology Laboratory in Winnipeg. There is no approved antiviral treatment or vaccine specifically for hantavirus, so care focuses on supporting patients through symptoms and complications, the journal says.
The Andes virus is unusual among hantaviruses because it can spread between people, according to CMAJ. Suspected Andes virus cases require isolation with airborne, droplet and contact precautions, involvement of infectious disease specialists and notification of public health authorities, the journal says.
Ebola outbreaks and testing
CMAJ says Ebola outbreaks have appeared periodically in Central and West Africa since the disease was identified in 1976. Three major Ebola viruses infect humans, and researchers consider fruit bats the likely natural reservoir, according to the journal.
The virus spreads through direct contact with bodily fluids, including blood, vomit, diarrhea and sperm, CMAJ says. Infection can also occur after contact with contaminated objects or surfaces, according to the journal.
The current outbreak in the Democratic Republic of Congo involves Bundibugyo ebolavirus, which CMAJ says has a reported fatality rate of 30% to 50%. Although Ebola is widely associated with bleeding, fewer than half of patients develop hemorrhagic symptoms, according to the journal.
Typical Ebola symptoms include a fever of at least 38 C, fatigue, muscle pain and gastrointestinal problems, CMAJ says. The incubation period ranges from two to 21 days, and diagnosis is confirmed with PCR testing.
CMAJ says testing and assessment should be considered for symptomatic people with possible exposure, including recent travel to countries with Ebola outbreaks, close contact with infected people, or contact with bats, primates or game animals from affected regions.
Treatment gaps remain
Health Canada recommends rigorous screening and protective measures for suspected Ebola cases, according to CMAJ. The recommended equipment includes a fit-tested N95 respirator, face shield, gloves and fluid-impermeable clothing.
CMAJ says vaccines against Zaire ebolavirus have shown strong effectiveness, and two antiviral treatments have lowered mortality from 50% to 35% for that form of the disease. The journal says no approved vaccine or medication is available to prevent or treat Bundibugyo ebolavirus, leaving supportive care as the main treatment for patients infected with that strain.
This story draws on original reporting from ScienceDaily.