Coronavirus disease 2019 (COVID-19)
There are no specific antiviral medications approved for the COVID-19 disease. Symptoms are managed with supportive care. Both the WHO and Chinese National Health Commission have published detailed treatment recommendations for healthcare professionals for hospitalized patients with SARS-CoV-2 infection.
WHO advises against the use of methylprednisolone unless the disease is complicated by acute respiratory distress syndrome. Corticosteroids are not routinely recommended for viral pneumonia and should be avoided unless they are indicated for another reason. The Beijing branch of China's National Health Commission suggested the use of lopinavir/ritonavir as part of treatment plans in the absence of an approved drug for this indication. The results of this study are not yet available. Chloroquine was being trialed in China in February 2020, with preliminary results that seemed quite positive. Another investigational antiviral drug remdesivir was reported to have in the laboratory activity against COVID-19. A small number of patients with COVID-19 have received intravenous remdesivir for compassionate use outside of a clinical trial setting.
Figure 1. SARS-CoV-2 outbreak 2020.
Middle East respiratory syndrome (MERS)
Currently there is no specific vaccine or treatment for the MERS disease. The WHO recommends that those who come in contact with camels wash their hands frequently and do not touch sick camels and that camel-based food products be appropriately cooked.
Neither the combination of antivirals and interferons or the use of corticosteroids improved outcomes. When rhesus macaques were given interferon-α2b and ribavirin and exposed to MERS, they developed less pneumonia than control animals. Five critically ill people with MERS in Saudi Arabia who were on ventilators were given interferon-α2b without succes. The treatment was started late in their disease (a mean of 19 days after hospital admission) and they had already failed trials of steroids so it remains to be seen whether it may have benefit earlier in the course of disease. Another proposed therapy is inhibition of viral protease or kinase enzymes. Researchers are investigating a number of treatments like the use of interferon, chloroquine, chlorpromazine, loperamide, lopinavir, remdesivir and galidesivir as well as other agents such as mycophenolic acid, camostat and nitazoxanide. Using extra-corporeal membrane oxygenation (ECMO) seems to improve outcomes significantly.
Severe acute respiratory syndrome (SARS)
As SARS (and all other coronaviruses) is a viral disease, antibiotics do not have direct effect, but may be used against bacterial secondary infection. Treatment of SARS is mainly supportive with antipyretics, supplemental oxygen and mechanical ventilation as needed. Antiviral medications are used as well as high doses of steroids to reduce swelling in the lungs. As of 2020, there is no cure or protective vaccine for SARS that has been shown to be both safe and effective in humans. According to research papers published in 2005 and 2006, the identification and development of novel vaccines and medicines to treat SARS is a priority for governments and public health agencies around the world.