A committee of the World Health Organization (WHO) Strategic and Technical Advisory Group on Infectious Hazards with Pandemic and Epidemic Potential (STAG-IH) was due to meet yesterday to consider the sudden explosion of monkeypox cases across the world.
More than 130 known (80) or suspected (50) monkeypox cases are under investigation in 12 non-African countries: Belgium, France, Germany, Italy, Netherlands, Portugal, Spain, Sweden and the United Kingdom, as well as as Canada, Australia and the United States.
Only one of those confirmed cases has been linked to travel from Nigeria, a country known to have endemic monkeypox. The man, who developed a rash on April 29, flew to the UK on May 4 and informed authorities of his symptoms. He was immediately isolated and the vials were taken and sent for PCR testing to Porton Down Science Park, which confirmed the infection on May 7.
What worries public health officials is that the cases are geographically scattered across Europe, the Atlantic and as far as Oceania. They suspect the disease has been spreading undetected for some time. These developments should come as no surprise, as all COVID social restrictions have been lifted and international flights have started carrying hundreds of millions of passengers this year. Meanwhile, public health efforts have been decimated by two years of relentless waves of infections.
WHO Regional Director for Europe, Dr Hans Kluge, noted: “Monkey pox is generally a self-limiting disease, and most infected people recover within weeks without treatment. However, the disease can be more severe, especially in young children, pregnant women, and immunocompromised people. It remains to be seen whether prior SARS-CoV-2 infection will predispose people to complications from monkeypox.
Genomic sequencing of the current strain of monkeypox suggests that it is West Africa’s least severe clade (genomic family), with a case fatality rate of less than 1%, or the benign version. The Congo Basin clade has a mortality rate of 10%. However, an article published in Nature said yesterday: ‘The exact difference between the strain causing the current outbreaks and that in West Africa – and whether the viruses emerging in various countries are related to each other – remains unknown.’
Dr Raina MacIntyre, an infectious disease epidemiologist and monkeypox expert at the University of New South Wales in Australia, said the answers to these questions are key to explaining whether the sudden rise in cases is an undercurrent. -product of a mutation that allows the monkeypox virus to transit more efficiently than ancestral versions. He would also answer if the outbreaks can be traced back to a single origin.
Deputy Director of the CDC’s Division of High Consequence Pathogens and Pathologies, Jennifer McQuiston, said earlier in the week of the monkeypox outbreak, “[While] we are seeing this expansion of confirmed and suspected cases around the world, we feel that no one has their arms around this to know how big and expansive this could be. And given the amount of travel between the United States and Europe, I’m very confident that we’re going to see cases in the United States.
Currently six people are being monitored who were close contacts with the man who returned to the UK from Nigeria. Another Massachusetts man with confirmed monkeypox had traveled to Quebec, where several cases have been confirmed. Another man currently at Bellevue Hospital is being investigated for infection, according to the New York City Health Department.
Disparate cases involve undetected spread. Usually, the disease manifests as lesions that begin on the face and spread to other parts of the body, developing into blisters that burst and then heal, resulting in pathognomonic (disease-specific) skin lesions. The consequence here is that monkeypox does not go unnoticed by the infected person or others. If the monkeypox virus spreads asymptomatically, it would have significant public health ramifications.
Health authorities have also been puzzled that most of the cases have been in young and middle-aged men, many of whom are gay or bisexual and have sex with men (GBMSM). MacIntyre said Nature she suspects “that the virus was introduced by coincidence into a GBMSM community, and that the virus continued to circulate there”. Such reports will certainly lead to further stigmatization of this community, as with HIV.
However, Dr Kluge warned: “As we enter the summer season in the European region, with mass gatherings, festivals and celebrations, I fear that transmission will accelerate as the currently detected cases are part of those who engage in sexual activity, and the symptoms are unknown to many.
Smallpox vaccines provide 85% protection against monkeypox because the smallpox virus is very similar. However, vaccination against smallpox ended in 1980 when the disease was eradicated, meaning people under 45 are unvaccinated and therefore fully susceptible to monkeypox virus. This of course includes all children, who are no less severely infected, as they have been so far with the SARS-CoV-2 virus. Additionally, decades of waning immunity to smallpox have likely made older people vulnerable again.
Public health authorities are trying to assure the public that sufficient supplies of smallpox vaccines, including antiviral treatments for monkeypox virus, are available. But instead of using them in mass vaccination campaigns, healthcare workers would use a method called “ring vaccination,” where close contacts of infected patients would receive these treatments. However, this implies that a contact tracing program would be needed to detail each chain of transmission.
Countries are beginning to secure contracts with the maker of the smallpox vaccine, Bavarian Nordic, a Danish company. On Wednesday, the company said BARDA (the U.S. Department of Health and Human Services’ advanced biomedical research and development authority for the Strategic National Stockpile) had exercised a $119 million option to manufacture the freeze-dried doses of Jynneos (live smallpox and monkeypox vaccine, non-replicating) in 2023 and 2024 to replace current bulk vaccine stock, according to Ferocious Pharma.
They also said: “US company Emergent BioSolutions also has an FDA-approved smallpox vaccine, ACAM2000, which is not available in the EU. Emergent has landed an award worth up to $2 billion to deliver ACAM2000 to the strategic national stock over 10 years.