Top of the pox
A story that is hard to miss, and is being reported on globally, is that of the current Monkeypox outbreak.
In the UK we are somewhat accustomed to hearing about Monkeypox cases, as every so often there are reports of travel related cases that pop up. So, at the beginning of May, when there were a couple of news reports about a man recently returned from Nigeria (where Monkeypox is endemic) testing positive for the virus, we thought nothing more of it. As usual, contact tracing was conducted, and further transmission from this index individual was deemed to be minimal.
However, on May 12, two new cases of Monkeypox were confirmed in London. These individuals were from the same household and found to have no link to the index patient, or travel to regions where the virus is endemic. On May 17, four more cases were confirmed by the UK Health Security Agency (UKHSA), three were from London and one from North East England who had recently travelled to London. None of these cases had a known contact history with any of the first three cases, or any recent travel history, suggesting that there was community transmission of the virus occurring in London.
Since mid-May cases have begun to snowball, and at the time of writing at least 221 cases have been confirmed, and more suspected, in 20 countries, with the UK currently having the highest case rate of 71. There is much work underway to identify where the outbreak began, the most predominant theory at present being that two raves in Spain and Belgium were superspreader events, and that the virus is spreading via sexual contact predominantly in the gay and bisexual communities, and to the wider community via routine contact with infected individuals.
Although case reports are growing rapidly, this is not the largest Monkeypox outbreak so far. To date the largest is the one currently occurring in Nigeria. The outbreak began in 2017, with over 500 suspected cases, over 200 confirmed cases and a case fatality ratio of approximately 3%, and cases continuing to be reported in 2022. There are two clades of Monkeypox virus; the West African clade and Congo Basin (central African) clade. Genomic sequencing of the virus currently circling the globe has confirmed that it is the West African clade of the virus, which caused an outbreak in 2018-19 in which there were around 130 confirmed and suspected cases in 10 countries.
At present, an action plan to tackle the spread of the virus is still being formulated. The WHO, CDC. European CDC, UKHSA, and others have released guidance on diagnosis, treament, and isolation periods etc, there has also been talk of undertaking ring vaccination in the UK of close contacts of infected individuals using Smallpox vaccine, although no plan for this has been confirmed. Cases and suspected cases seem to be rising rapidly, so there is no doubt we will continue to see cases for some time yet.
To some, this outbreak is not necessarily a surprise. In a 2020 paper titled 'Modelling human-to-human transmission of monkeypox', by a team of researchers from the Institut Pasteur, Emerging Diseases Epidemiology Unit, it was posited that "The geographic spread of monkeypox cases has expanded beyond the forests of central Africa, where cases were initially found, to other parts of the world, where cases have been imported. This transmission pattern is likely due to the worldwide decline in orthopoxvirus immunity, following cessation of smallpox vaccination, once smallpox was declared eradicated in 1980. Monkeypox could therefore emerge as the most important orthopoxvirus infection in humans".
The past two years of lockdowns, face coverings, and other non-pharmaceutical virus countermeasures has seen the immunity debt (lower immunity to infectious diseases due to not being exposed to them in day to day life) of the general population increase, and we have have begun to see the effect of this in terms of common colds affecting people more like the flu, an increase in Meningitis cases, the current acute hepatitis outbreak in children, and perhaps also this Monkeypox outbreak. Further investigation is ongoing, but we will keep an eye on things and report back on what we find.
In the meantime it wouldn't be a proper outbreak without some crackpot theories, so far we have come accross: 'This is a shingles outbreak caused by the Astazeneca Covid vaccine and Monkeypox is being used to cover this up', 'It is caused by the chimpanzee adenovirus in the Astrazeneca vaccine', 'It leaked from the same Wuhan lab as Covid', and 'The USA deliberately realeased the virus to sell Smallpox vaccines'.