Researchers with exceptionally good timing have released a report on the first use of antivirals as a treatment for monkeypox patients. When the research started they were investigating a disease seldom seen outside West and Central Africa and largely ignored by scientists and the general public alike. Now their paper has arrived while people are questioning if this will be the next pandemic.
The current wave of monkeypox infections in Europe, America, and other countries is not the first time this orthopoxvirus has left Africa in recent years, but it is by far the biggest outbreak. Between 2018 and 2021, however, seven patients were diagnosed with monkeypox in the UK. A new study in The Lancet Infectious Diseases suggests that some antiviral medicines may help shorten symptoms and how long a person is contagious, but the authors warn the sample size was far too small to draw firm conclusions about the effectiveness of treatments.
Monkeypox occurs in a variety of African animals (although not normally monkeys), and usually crosses to humans through animal bites or scratches, or the handling of wild animals for food. Human transmission comes from close contact. Its symptoms appear similar to chickenpox and smallpox, but can also be lethal. Between 1-10 percent of humans infected die, but fortunately, the strain currently spreading in at least 12 countries is among the less deadly ones.
The cases covered in the paper include the first recorded example of transmission in a hospital and the first two household transmissions outside of Africa. All seven patients were placed in isolation, and all made full recoveries, somewhat predictably since all were infected with the less dangerous West African strain. Hospitals treated four of the patients with either brincidofovir or tecovirimat. Both are antivirals developed as defenses against smallpox after its eradication, in case bioterrorists tried to bring back the virus that killed more humans than any other infectious disease.
The monkeypox virus is so closely related to the smallpox virus the smallpox vaccine is 85 percent effective against it, so the use of the drugs made sense. Opportunities to confirm the effectiveness of either medication against smallpox itself have thankfully been zero outside laboratories since the drugs' invention, so their effectiveness was established partly against monkeypox in animals.
We know not all drugs that work in non-human animals are also effective in people, and the same may be true of brincidofovir. The three patients treated with this drug show no better recovery rate than their counterparts, and also showed elevated liver enzymes.
Tecovirimat was given to only one patient, so the fact she suffered the fewest lesions and made the fastest recovery among the seven could be coincidence. Nevertheless, the recipient spent 10 days in hospital, compared to an average of 27 for the others, and also suffered no side effects. However, one of the patients who did not receive antivirals was out in 13 days, so more data is definitely needed.
Aside from the antiviral treatment, the study also reported: “Low mood was common among our patients; however, their mood could have been an appropriate and predictable reaction to prolonged hospital isolation without visitors for infection control purposes.” Notably, stigma could be as problematic as the disease itself. “One patient’s landlord attempted to evict them during their admission,” the paper reports.
“Although this latest outbreak has affected more patients than we had previously encountered in the UK, historically monkeypox has not transmitted very efficiently between people, and overall the risk to public health is low,” first author Dr Hugh Adler of Liverpool University said in a statement.
The same conclusion reached in more poetic form can be seen here:
Nevertheless, senior author Dr Nick Price of Guy's & St Thomas' NHS Foundation Trust noted: “The cases we observed were challenging and resource-intensive to manage, even in the high-income setting of the UK.”