9. Diagnosis and treatment of hantavirus infections
Epidemiological information and clinical symptoms are useful for the
initial diagnosis of hantavirus infections. Confirmation of hantavirus
infections should be based on clinical symptoms, epidemiological
information, and detection of the nucleic acids, proteins, and/or
antibodies specific to the associated hantavirus.65
No specific antivirals have been approved for HFRS and HCPS/HPS in the
USA or Europe.5 However, some antivirals, including
ribavirin, fapilavir, and lactoferrin, have displayed varying efficacy
in the treatment of hantavirus infections.91
Prophylactic administration of
ribavirin and fapilavir in early infection or post-exposure has shown
some efficacy.92 Both ribavirin and fapilavir have
shown anti-hantavirus activity in vivo and in
vitro.5,91 Ribavirin has proven effective in the early
treatment of HFRS with some limitations, including toxicity to humans
and animals at high doses and the potential to cause hemolytic
anemia.92 Fapilavir is superior to ribavirin without
the side effect associated with anemia.77 Fapilavir
was evaluated in an ANDV/SNV-infected hamster model, where oral
administration twice daily at 100 mg/kg significantly reduced the viral
RNA load in the blood and the antigen load in the lung. Oral
administration of fapilavir before the onset of viremia prevented HCPS,
whereas delayed administration had no protective
effect.91
Antibodies include monoclonal and
polyclonal antibodies.91 Monoclonal antibodies that
are effective against hantaviruses have been demonstrated in hamster
models and suckling mouse models.91 Monoclonal
antibodies have been proven effective for treatment of HCPS/HPS induced
by ANDV infection in hamster models.93 Polyclonal
antibodies produced by DNA-vaccinated bovines have also displayed
protective effects in animal models.65
Supportive treatment can be used to maintain fluid and electrolyte
balance in HFRS patients, while blood transfusions can control bleeding
and improve clotting in DIC cases. For HCPS/HPS patients, oxygen
supplementation is usually required.5