The Journal of the Canadian Medical Association recently published two briefings focusing on two highly lethal viral diseases that have recently attracted public health attention again - hantavirus infection and Ebola virus disease. Studies have pointed out that both diseases may only present non-specific flu-like symptoms in the early stages of the disease, but the progression of the disease is often dangerous. If strict infection prevention and control measures cannot be identified early and strict infection prevention and control measures are not implemented quickly, it can easily lead to serious consequences.
The article emphasizes that although there are significant differences between hantavirus disease and Ebola virus disease in terms of pathogen type, mode of transmission, and clinical outcomes, the early clinical manifestations, such as fever, headache, muscle aches, and gastrointestinal symptoms, are highly overlapping and can easily be confused with common respiratory infections. Therefore, clinicians should remain highly vigilant and proactively conduct risk assessment and laboratory testing when facing "influenza-like" patients with corresponding exposure history or epidemiological associations.
In Canada, hantavirus infection is classified as a nationally notifiable disease, and every confirmed case must be reported to public health authorities. About four to five confirmed cases of hantavirus are reported in the country each year, mostly linked to rodent exposure in agricultural areas of Manitoba, Saskatchewan, Alberta and British Columbia. It is worth noting that one of the strains, called Andes, is relatively special and has the ability to spread from person to person. Recent related cases have also attracted media attention.
Hantaviruses circulating in different regions can cause different types of clinical syndromes: In the Americas, various hantaviruses, including Andean strains, mainly cause hantavirus cardiopulmonary syndrome; while in Europe and Asia, hemorrhagic fever-type diseases characterized by renal damage are more common. The incubation period of the two types of diseases is usually two to four weeks. Early symptoms are often not specific, including fever, headache, muscle aches and abdominal pain. As the disease progresses, heart, lung or kidney function can be rapidly affected.
Laboratory diagnosis of hantaviruses relies on serological and polymerase chain reaction (PCR) tests, which are performed in Canada by the National Microbiology Laboratory in Winnipeg. Currently, there are no specific antiviral drugs or vaccines approved for hantavirus infection. Clinical management is mainly supportive treatment, focusing on maintaining the stability of vital signs and supporting organ function.
In view of the risk of human-to-human transmission of the Andean strain, experts recommend that strict infection prevention and control measures must be implemented for suspected related cases. Medical institutions should adopt multiple protection measures such as air isolation, droplet isolation and contact isolation for patients, and isolation management should be implemented throughout the entire diagnosis and treatment process. At the same time, infectious disease specialists should intervene in management as early as possible, and all suspected and confirmed cases should be reported to the public health department in a timely manner so that epidemiological investigations and close contact tracing can be carried out.
Compared with hantavirus, Ebola virus disease has long been regarded as a major threat to global public health. Since it was first discovered in 1976, it has caused multiple large-scale outbreaks in Central and West Africa. There are currently three types of Ebola viruses known to infect humans, and studies generally believe that fruit bats are their natural reservoirs. The virus is spread through contact with blood, vomit, diarrhea, semen and other infected body fluids, as well as contaminated surfaces or objects, and medical exposure and funeral customs may pose high risks.
The report mentioned that the Democratic Republic of the Congo is experiencing an epidemic caused by the Bundibugyo ebolavirus. The case fatality rate of this strain of the virus is reported to be between 30% and 50%. Although the public often associates Ebola with severe bleeding symptoms, in fact less than half of patients will develop typical bleeding symptoms, and more cases start with high fever, extreme fatigue, muscle aches and gastrointestinal symptoms.
The incubation period of Ebola virus disease is generally two to 21 days, and diagnosis also relies on PCR testing. Experts suggest that people who have recently traveled to countries with Ebola epidemics, or who develop related symptoms after contact with confirmed patients, suspected patients, or bats, primates or game from affected areas, should undergo professional evaluation and laboratory testing as soon as possible.
Canadian health authorities recommend that suspected Ebola cases must implement strict infection prevention and control procedures, including a hierarchical screening and assessment system, as well as specialized training for front-line medical staff. In terms of personal protective equipment, it is recommended to wear a complete set of protective equipment such as N95 respiratory protective masks, face shields, anti-penetration protective clothing and disposable gloves that have been fit-tested to minimize the risk of occupational exposure.
In response to Ebola, the scientific research community has made substantial progress in recent years. For Zaire ebolavirus, highly effective vaccines have been approved for use and have shown good results in preventing outbreaks and protecting high-risk groups. At the same time, the application of two antiviral drugs has reduced the overall mortality rate of this type of Ebola virus infection from about 50% to about 35%, significantly improving patient prognosis.
However, for the Bundibugyo Ebola virus involved in the current outbreak in the Democratic Republic of the Congo, there is no approved specific vaccine or antiviral drug, and clinical treatment still focuses on comprehensive supportive care. This also means that early identification of suspected cases, blocking the chain of transmission and strengthening the ability to treat severe cases are still the keys to preventing and controlling this type of Ebola epidemic.
Two articles published in the Journal of the Canadian Medical Association aim to provide frontline clinicians with the latest concise guidance on the diagnosis, treatment and infection control of hantavirus infection and Ebola virus disease, helping medical staff to quickly identify high-risk patients with limited clues and take appropriate responses. Experts emphasize that in the context of increasingly frequent global travel and cross-border activities, even in countries and regions outside traditional high-incidence areas, medical systems must have the ability to identify and respond to these highly lethal infectious diseases in order to reduce public health risks and save more lives.