Sunday, September 09, 2018

UK: PHE Statement On Imported Monkeypox Case


Five days ago, in JFK Quarantined Flight & Airport Screening For Infectious Diseases, we looked at how efficiently international air travel can disseminate infectious diseases around the world, and our limitations in preventing their arrival.

Since then, as if to prove the point:
Nigeria, which saw its first Monkeypox outbreak in nearly 40 years last fall, issued their last SitRep in February (see An Update of Monkeypox Outbreak in Nigeria for Week 9), which indicated the outbreak was winding down.

Although Monkeypox is normally restricted to small outbreaks in Africa, in 2003 the United States experienced a rare outbreak when a Texas animal distributor imported hundreds of small animals from Ghana, which in turn infected prairie dogs that were subsequently sold to the public (see MMWR Update On Monkeypox 2003).
By the time this outbreak was quashed, the U.S. saw 37 confirmed, 12 probable, and 22 suspected human cases. Among the confirmed cases 5 were categorized as being severely ill, while 9 were hospitalized for > 48 hrs; although no patients died (cite).
While we've not heard of any recent resurgence of Monkeypox in Nigeria, yesterday the UK's PHE issued the following statement on an imported case diagnosed in Cornwall in a recent arrival from Nigeria.

I'll return with a bit more on Monkeypox after the break.
Monkeypox case in England

First case of monkeypox confirmed in England.

Published 8 September 2018
From: Public Health England

Public Health England (PHE) can confirm an individual has been diagnosed with monkeypox in England. This is the first time this infection has been diagnosed in the United Kingdom (UK).

Monkeypox is a rare viral infection that does not spread easily between people. It is usually a mild self-limiting illness and most people recover within a few weeks. However, severe illness can occur in some individuals.

The infection can be spread when someone is in close contact with an infected person; however there is a very low risk of transmission to the general population.

The patient was staying at a naval base in Cornwall prior to transfer to the expert infectious disease unit at the Royal Free Hospital, London where they are now receiving appropriate care.

The patient is a resident of Nigeria, which is where they are believed to have contracted the infection, before travelling to the UK.

As a precautionary measure, PHE experts are working closely with NHS colleagues and will be contacting people who might have been in close contact with the individual to provide information and health advice.

This includes contacting a number of passengers who travelled in close proximity to the patient on the same flight to the UK. People without symptoms are not considered infectious but, as a precaution, those who have been in close proximity are being contacted to ensure that if they do become unwell they can be treated quickly. If passengers are not contacted then there is no action they should take.

Initial symptoms include fever, headache, muscle aches, backache, swollen lymph nodes, chills and exhaustion. A rash can develop, often beginning on the face, then spreading to other parts of the body. The rash changes and goes through different stages before finally forming a scab, which later falls off.

Dr Michael Jacobs, clinical director of infection at the Royal Free Hospital, said:
Monkeypox is, in most cases, a mild condition which will resolve on its own and have no long-term effects on a person’s health. Most people recover within several weeks.

It is a rare disease caused by monkeypox virus, and has been reported mainly in central and west African countries.

It does not spread easily between people and the risk of transmission to the wider public is very low. We are using strict isolation procedures in hospital to protect our staff and patients.
Dr Nick Phin, Deputy Director, National Infection Service at PHE, said:
It is important to emphasise that monkeypox does not spread easily between people and the overall risk to the general public is very low.

Public Health England is following up those who have had close contact with the patient to offer advice and to monitor them as necessary.

PHE and the NHS have well established and robust infection control procedures for dealing with cases of imported infectious disease and these will be strictly followed to minimise the risk of transmission.

The name `monkeypox’ is a bit of a misnomer. It was first detected (in 1958) in laboratory monkeys, but further research has revealed its host to be rodents or possibly squirrels. It produces a remarkably `smallpox looking'  illness in humans, albeit not as deadly.

Humans can contract it in the wild from an animal bite or direct contact with the infected animal’s blood, body fluids, or lesions, but consumption of under cooked bushmeat is also suspected as an infection risk. Human-to-human transmission is also possible.
According to the CDC: There are two distinct genetic groups (clades) of monkeypox virus—Central African and West African.
West African monkeypox is associated with milder disease, fewer deaths, and limited human-to-human transmission.
The more virulent form of Monkeypox is commonly found in the Central Africa countries of the DRC and the CAR - where outbreaks have been on the rise for years (see here and here) - presumably because smallpox vaccinations (which provided up to 85% protection) were halted in the late 1970s.
Unfortunately, as the percentage of vaccinated members of the community dwindles, the risks of outbreaks is only expected to increase (see 2010 PNAS study Major increase in human monkeypox incidence 30 years after smallpox vaccination campaigns cease in the Democratic Republic of Congo).
Like all viruses, Monkeypox continues to evolve and diversify, as discussed in the 2014 EID Journal article Genomic Variability of Monkeypox Virus among Humans, Democratic Republic of the Congo, where the authors cautioned:
Small genetic changes could favor adaptation to a human host, and this potential is greatest for pathogens with moderate transmission rates (such as MPXV) (40). The ability to spread rapidly and efficiently from human to human could enhance spread by travelers to new regions.
Although the risks to the general population in the UK are likely very low - and this imported case is presumably the milder, harder to transmit `West African' clade - Monkeypox is one of those re-emerging infectious diseases we watch closely, as declining community immunity viral and evolution could one day permit this virus to spread in a more sustained manner.

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