Monkeypox leaves Africa

Herald Reporter
The present May outbreaks of monkey pox in Europe and North America, with around 200 cases of transmission from human to human this month, according to the World Health Organisation, has suddenly grabbed global media attention from what had been very largely an ignored disease of the rain forests in Central and West Africa.

The affected African countries have been dealing with the disease for decades and are combating it effectively with support from the World Health Organisation. Africa would be horrified at more than 200 cases in less than a month but the WHO has noted that the disease was largely ignored when only in rain forest Africa.

Monkeypox is misnamed, since a handful of species of rodents appear to be the main reservoir, but received its present name in 1958 when it was first identified in Denmark in a laboratory monkey, a cynomologus monkey. The first human case positively identified was in a nine-month-old boy in Equateur province of the Democratic Republic of Congo.

It was likely that there had been other earlier human cases but that these would have buried in the statistics for the closely related but, at that time, far more common and far more lethal smallpox, since the external symptoms are so similar.

Since smallpox vaccine is 85 percent effective for Monkeypox the mass vaccination drive in the 1960s and 1970s that eradicated smallpox, following up on extensive and earlier smallpox vaccination, also suppressed Monkeypox infection in the human population. Unfortunately the rodent reservoir did provide new sources of primate infection, in both humans and monkeys.

Since the WHO recommended the end of smallpox vaccination in 1980, there has been a growing percentage of the African population without this vaccine protection, since the last shots were given more than 40 years ago, and in most other parts of the world there are few people under 50 who have ever had a smallpox vaccination.

Since 1970 and the first confirmed human case a lot of research has been done on the virus. It is one of the 12 known viruses in the Orthopox genus, the important other ones being variola, which caused smallpox, plus the viruses for the non-lethal cowpox, horsepox and even camelpox. A critical species is vaccinia virus, related to horsepox, that was used as the modern source of smallpox vaccine after late 18th century experiments with cowpox. The Latin word for cow in fact gave vaccination its name in other languages.

Monkeypox, like its relatives, is a double-stranded DNA virus. Being DNA-based its mutation rates are low, and far lower than those seen in RNA-based viruses like HIV and Covid-19.

There are two types, called clades, of Monkeypox: one centred in the Congo basin and in particular the DRC and one on West Africa, ranging from Cameroon to Ghana, although it has only been seen in animals in Ghana. The main difference is that the Congo version has a fatality rate in humans of around 11 percent while the West African clade has a human fatality rate of less than 1 percent.

The strain in the present outbreak seen outside Africa is the West African one.

Monkeypox is not highly infectious and the WHO reckons the longest known chain of infection in humans is six. Much African infection came from preparing infected animals, mainly three species of rodent although some monkeys used in bushmeat might have been infected, with human-to-human contact only becoming important recently.

Africa has been having to cope with Monkeypox for decades before it reached the western headlines. DRC has the worst rates, building up after smallpox vaccination was discontinued, and now close on 1000 cases a year. This variety was also seen in South Sudan in 2005 but with no fatalities.

West Africa has seen a recent outbreak in Nigeria. Between 1971 and 1978 there were just 10 human infections in that country and then it vanished for 39 years among people. In September 2017 it re-emerged and in the almost five years to early May this year there were 230 confirmed cases. The Nigerian health authorities think the number is probably larger because during the worst of Covid-19 a lot of people were reluctant to crowd at health centres.

There were sporadic out of Africa bursts of infection, all from the more mild West African version, the most famous being in 2003 in America when a young child in Wisconsin was bitten by a prairie dog bought in a swop meet. In the end 71 infections were reported and all were eventually traced to a batch of Gambian pouched rats bought by a Texas exotic animal dealer from Ghana. But all humans infected had been in close contact with prairie dogs.

There was a small outbreak in May last year in Wales, with three people, and a single case two months later in the USA involving a man who had just returned from Nigeria.

The present multi-country outbreak is likely to have multiple sources but has largely spread within the male gay community. It is suspected that there could be a focus of infection dating back some time in London and other parts of Europe, but two gay rave parties in Belgium and Spain gave it a sharp kick upwards.

While infection through sexual contact remains a possibility, since a third of infected people develop genital lesions, it is known that close physical contact with an infected person is far more likely as lesions develop elsewhere in two thirds of cases, and sexual contact usually involves such very close contact. So everyone is at risk if they are in very close contact with an infected person.

The initial British case in the present wave was recorded on May from a person who had developed a rash while in Nigeria at the end of April and checked into hospital in Britain on their return. But the other British infections appear to have other sources.

Two other British cases turned up shortly afterwards, the two living in the same household, and neither being in contact with anyone associated with the first case or who had been on holiday in Africa. Three more Londoners and a person who had been in London turned up later. This is what has given rise to the suspicion that there Is a focus in London. Another 11 British cases had turned up by May 20 with gay men urged to be watchful and so suggesting these were largely in that community. Since then the British total has reached close on 100.

Portugal, Sweden, Belgium and Italy reported cases, and in Italy just one, less than two weeks ago, followed by a case in Massachusetts on May 19 and then cases in Switzerland and Israel reported on May 21 with Spain reporting 23 new cases the same day, all linked to a gay bathhouse in Madrid and taking the Spanish total to 30. A gay pride festival in the Canary Islands has also come under suspicion for several infections in Spain and elsewhere.

Last week Austria, Canada, Czech Republic (a woman at a Belgian music festival early in May), and a lot more cases in Britain were reported. Virginia reported a case, a woman recently in Nigeria, Finland reported one and Argentina reported two people recently in Spain. All cases so far are of the milder West African variety no deaths out of Africa have been reported. Monkeypox has now hit nine Americans in seven states.

This is what is making the headlines, the headlines that were conspicuously missing when it was just something in Africa.

The symptoms of monkeypox are easily confused with chickenpox, and even measles although that Is largely eradicated, and smallpox, which is eradicated. The onset of infection is marked by flu-like symptoms, headache, muscular pains, fever and fatigue. This is followed by swollen glands behind the ear, below the jaw, in the neck or in the groin before the onset of the rash.

Then come the lesions in most cases, starting on the face then on the palms and the soles of the feet. They begin as small flat spots which develop into small bumps that fill with clear fluid, turning to yellow before the lesions burst and scab over, very similar to smallpox. This rash lasts around 10 days and the whole period of illness two to four weeks. Pale scars that eventually fade may be left.

First symptoms can appear up to 21 days from infection. PCR tests are now available to distinguish monkeypox from chickenpox but the tests only really work on samples from the lesions as the disease does not remain long in the blood.

Transmission between humans is uncommon in Africa, where most infections come from animals, although the few hundred cases in the latest out-of-Africa wave are human to human. Those in danger are people who get very close to an infected person, basically health personnel, people living with an infected person, and people having close body contact.

What is worrying experts is why the disease spread in human-to-human contact to so many score, when many African infections come from animals and the chains quickly die out as health authorities take action.

Since monkeybox is a virus there is no surefire cure, but techovirimat, an antiviral developed to treat orthopox virus infections, is used in Europe and North America. While a monkeypox vaccine has been developed, the old smallpox vaccines that use vaccina virus are the ones that are available and are 85 percent effective.

Even people vaccinated 40 to 50 years ago, and some of those with monkeypox in the present wave have apparently been old enough to have been vaccinated as children, seem to have less severe symptoms.

The USA is busy increasing its stockpile of smallpox vaccine, although this is largely for issuing if there is biological warfare using smallpox but has made it available for health staff. Smallpox vaccine is that it infects the recipient with the vaccina virus and so gives protection against the rest of the orthopox viruses.

But in a small minority of cases the vaccine can produce complications and it is not recommended for pregnant women. People with impaired immune systems, such as being on chemotherapy or infected with HIV, are more likely to have the complications, which are not lethal but not pleasant.

When smallpox killed more than 35 percent of infected people no one fussed much about the complications in a very small fraction of the vaccinated, since the benefits were so enormous when compared to the discomfort in a few, but when smallpox was eradicated in each area the WHO did withdraw recommendations for mass vaccination.

It has been noted that since infection is from exceptionally close contact the protocols in place to prevent Covid-19 infection work. The WHO has recommended the same personal protection equipment for health staff dealing with potential monkeypox patients. Those who attend large crowded events where there could be someone with monkey pox are advised to follow the good old masking and hygiene rules that brought them through Covid-19.

Africa, the origin of monkeypox, has very low infection rates simply because of the action of the health authorities in the four countries with recent infection, like the last 20 years: DRC, South Sudan, Nigeria and Benin, and the general watchfulness in the other half dozen, largely the general advice not to eat a range of wild animals and symptoms warnings. But cases have been growing as a result of the wearing off of smallpox vaccination.

Monkeypox is low-level infectious, and unlikely to explode, but it does need the advice and contact tracing used in West and Central Africa to keep global infections in the scores.