Monkeypox and an Interesting Look at Changes in Epidemiology

For decades, monkeypox virus was only a disease that infected animals but, in the 1990’s it found a new target in humans. This paper dives into the history of human monkeypox and the root of the cause right from the start. The aim here is to understand the underlying cause for the sudden rise in monkeypox cases in regions that are not conducive to the disease. Throughout the paper, there will also be a list of activities mentioned that people ought to avoid when a known person is infected. Overall, by the end of the paper there will be a clear idea of do’s and don’ts regarding monkeypox virus.

The creation of the Monkeypox originates from the virus known as the Monkeypox virus. This virus belongs to the orthopoxvirus which is a complete group of viruses. The disease is native to rain forest countries belonging to central as well as western parts of Africa. Originally this disease had been discovered in laboratory monkeys in the year 1958. In the latter years, several tests conducted on the blood of animals residing in the African continent led to the revelation that monkeypox virus had entered the system of several African rodents [1].

As for the past of monkeypox, it is tangled with smallpox. The first known sighting of smallpox is believed to have occurred around 10,000 B.C.E. Smallpox has caused the death of over 300 million people just during the 20th century only. In the past a great number of countries have tried to prevent the spread of smallpox. There was no stone left unturned and in their desperate attempts people sniffed up dried smallpox scabs and even punctured others with the help of iron needles that had just been dipped in smallpox pustules. The measures taken in this regard have been referred to as inoculation and have been practiced in countries such as, Turkey, India, China and Africa.

This process also made its way to Europe but not before the dawn of the 18th century. It was Lady Mary Wortley Montagu who brought the practice to England after her stay in Turkey with her husband, the British ambassador to the Ottoman Empire [2].

Monkeypox virus was first discovered to have affected the human body in 1970. The victims were residents of remote African locations. From that time onward, monkeypox cases in human body have been reported in 11 countries. Of those, the most notable countries with Monkeypox cases are, Nigeria, Liberia, Congo and Cote d’Ivoire. During this period, the actual depth of monkeypox could not be identified as well as its original burden.

For a period of 6 years starting from 1981 and ending in 1986, a total of 37 cases had been reported in the country of the Democratic Republic of Congo formerly known as Zaire. Perhaps the biggest danger of Monkeypox had been realized in 1996-97 in the Democratic Republic of Congo. The outbreak had been reported to have a low case of fatality ratio while the attack rate was on the higher side. Concerns had been raised regarding the retention of smallpox virus samples in the case of pursuing comparative research with monkeypox. A total of 71 clinical cases of people suffering from monkeypox had been reported over a duration of 7 months, starting from February and lasting till August, 1996. There were a total 6 deaths in this period along with those cases and all of them had been reported from 13 villages in Zaire.

Most of the secondary cases had been reported during the month of August, 1996. This month is significant because the outbreak was at its peak. There was a sum total of 11 specimens collected with every one of them being positive for monkeypox. In addition, the 11 specimens would go on to exhibit small genetic variation in comparison with the rest of the strains collected during a 10-year period from 1970 to 1979. The outbreak would carry on as the World Health Organization reported with the help of local health workers and stated that the number of newly infected cases rose to 170 during a 3-month period starting from March and ending in May of 1997.

At this point in time, the chief of WHO’s new branch was a man named David Heymann and his branch was created for the sole purpose of detecting emerging diseases. According to Heymann, some of the cases could well have been chicken pox.

Ever since September of 2017, there has been a huge outbreak of monkeypox cases in the country of Nigeria. As a matter of fact, the latest reappearance of monkeypox has been the biggest in the country. Over a 2-year period, reports came in stating 183 confirmed cases of monkeypox in 18 states. While it is alarming to report so many cases, the situation provides an explanatory case study regarding the arrival of zoonosis. It is due to the fact that there is presence of epidemiologic characteristics.

In the year of 2018, a separated sample of the Monekypox virus had been derived from Cameroon which revealed to have carried similar genetics to that in Nigeria. The surprise factor in this case is that there is no chance of there being any epidemiologic linkage [3]. As such, there is a strong possibility of an epizootic event that spreads across the Nigeria-Cameroon borders.

The finding raised more questions since it does not match the general characteristics of the West African clade. In fact, the natural state of these regions dictate outbreaks that can be separated on a temporal and geographical level [4]. In addition, the outbreak that took place in Nigeria from 2017-2020 revealed the statistic that it was mostly adults who had been affected by the virus. Of the patients affected by the virus, almost 4/5th of them (78%) were between the ages of 21-40 years. This is a complete contrast to the past. Before that outbreak, majority of the victims of the virus had been aged below 15 years.

By the 21st of May, 2022, there had been a total of 92 laboratory confirmed cases of the Monkeypox virus. In addition, there had been 28 suspected cases which was enough to continue investigations into the matter by the WHO. These reports were sent to the WHO by 12 Member countries. The surprise factor here again is that none of these regions are endemic for the virus (Table 1).

This adds to growing concerns in the countries represented in the image (Figure 1).

Figure 1: Geographical distribution of Monkeypox virus sourced from WHO.

Of the cases that were reported to the WHO, there have been zero travel links to the endemic regions of the world. There has been little information to go on without the travel links. However, on the basis of the information that has been obtained, the WHO has identified the cases (not most but a substantial amount) amongst men who had sex with other men (MSM) and have sought care in sexual health clinics as well as the primary care [5].

With that said, it is not so easy for Monkeypox virus to spread from one person to another. The virus is likely to spread to an individual if they happen to have close contact with an animal that has been infected already. On that note, there have been concerns that rodents may well be the primary animal which can transmit the virus to human beings. Furthermore, it can also be other human beings or materials which were polluted by the virus. The road for the virus starts with broken skin on the body of human beings even if the visibility is low as well as respiratory tract. To add to that, there is a possibility for the virus to enter with the help of mucous membranes such as, eyes, nose and even the mouth.

Despite grown concerns over MSM, it is still not so common to have cases of the virus spreading from one individual to another. If one person comes into close contact with clothing or linens that have been used actively by an infected person then it is likely to spread the virus. The linens in question are bedding or towels. Other than that, the virus may also spread to another human being if they come in close contact with scabs of monkeypox skin. In addition, people also run the risk of contracting the virus if they stand within close proximity of an infected individual when they are coughing or sneezing [6].

Around May of 2022, the surveillance in the non-endemic regions had been on the lower side. However, the WHO has reasons to believe that surveillance has to be increased so that the situation does not get out of their control. There is also a possibility of cases increasing in the non-endemic regions and that they will be reported to the WHO. For the virus, there is an incubation period that normally ranges from 6-13 days. Yet, it is also possible for that time period to vary from 5-21 days.

While rodents have been suspected of being the common source of transmission, it will be unwise to rule out other animals. A number of animal species have recently been pointed out for having susceptibility to this virus. There is a great deal of uncertainty when it comes to the natural history of this virus. As such, the only way to confirm the accurate reservoir is to conduct multiple studies on the subject matter. If studies can be conducted thoroughly then it will lead researchers to figure out the ways in which the nature maintains the virus circulation. If people intake meat that was poorly cooked or even intake animal products sourced from infected animals then there is a possibility of contracting the virus.

There may be some form of relief in knowing that Monkeypox virus is known for being self-limiting. Even so, a possibility also exists that some individuals will be more susceptible to the virus. For instance, children as well as pregnant women could well be more susceptible to it than others. In addition, individuals who have to live with a suppressed immune system affected by other health conditions also have higher susceptibility to this virus.

Monkeypox virus has been known to have occurred a handful times across history. This is why Professor Jimmy Whitworth of the London School of Hygiene and Tropical Medicine, believes the rise in cases to be unusual. By the end of 2021, a large number countries lifted the travel restrictions for COVID-19. Whether it was a result of falling economies or otherwise, there can be a link with the lift of travel restrictions and the rise in Monkeypox virus cases [7].

On the other hand, Professor Raina McIntyre presents a different view. According to the Professor from Kirby Institute, there is a decrease in immunity from the smallpox vaccinations that have possibly led to the rise in outbreak of the virus. She has added that, there is currently a gap of nearly 50 years since mass vaccination was put to a halt. There is a possibility that the smallpox vaccinations would have prepared humans with strong protection when monkeypox eventually made its presence known. For some countries dealing with the monkeypox virus, there was never a widespread smallpox vaccination program such as, in Australia.

Not too long before the WHO made the news known, it was actually epidemiologists who brought the growing number of Monkeypox cases to light. In fact, the epidemiologists asked for an upgrade in terms of worldwide surveillance as well as being able to detect monkeypox cases even before the outbreak could happen. It is due largely to the fact that all of the data strongly suggested a reemergence of this virus.

Over a period of 10 years, starting from 2010 and ending in 2019, there was a reappearance in cases in countries such as, Liberia and Sierra Leone. Before the year 2010, there was a huge gap of four decades in the appearance of cases. On the other hand, there had been a three-decade gap between cases reported in the Central African Republic [8].

As previously stated, it is difficult for the virus to spread from one human being to another just like that. According to a study, a mere 3% of individuals coming in close contact with an infected person is likely to become infected [9].

With that said, the rise in cases will no doubt raise some eyebrows. There are concerns that the virus may have undergone mutations and the current mutation makes it easier to be transmitted from one individual to the other. The best route to confirm the concern is not just some hypothesis, rather the best course of action is going to be additional lab and data analysis. Only then will there be conclusive evidence pointing to the exact reasons.

As of now, laboratories have already begun sequencing of monkeypox virus. Despite the fact that the virus has stuck around for such a long duration, there is much to learn about it and it can still be considered as a rare disease.

Among the recent outbreak, there have been clusters of cases that is presumed to have occurred due to MSM. With that said, there has been a statement issued by The United Nations’ Aids agency calling the reports on monkeypox to be racist as well as homophobic. A warning has been issued with the organization urging people not to exacerbate the stigma while also telling people not to undermine the outbreak itself.

Monkeypox is said to have been transmitted due to close contact on a physical level with an infected person. As such, it could be transmitted to anyone and not just men. So, the current portrayal of the inhabitants of Africa as well as LGBTI people can end up reinforcing the stereotypically racist and homophobic views according to The United Nations’ Aids agency.

Matthew Kavanagh who is the deputy executive director of UNAIDS has gone on record to state that stigma is going to undermine trust along with the capacity for responding effective when an outbreak of this magnitude takes place. Looking back on the past, it can be said that provoking stigma has led to evidence-based response being disabled. This is a result of fear being invoked into the mind of people which leads them away from visiting health centers. In addition, it may result in people taking up measures that provide lackluster returns [10].

The possibility still remains that the virus has not undergone any mutation whatsoever rather, it has seized the perfect opportunity when the situation presented itself. It is entirely possible for an entire community of people to be living in close contact which leads to several chances of spreading.

Outside of Africa, the first ever outbreak of the virus had been reported in 2003 in the USA. The cause of the outbreak is the shipping of 800 small mammals residing in Ghana to the state of Texas [11]. This shipment contained three rope squirrels, nine dormice as well as two giant pouched rats which had been infected by the virus [12]. It was a wholesale distributor who bought the infected rodents. After the purchase, the distributors kept the rodents in close contact with dogs, specifically of the American native prairie breed.

This event was followed by the dogs being infected and subsequently sold to another animal distributor [13]. As a result of these events, the virus began spreading and had affected five states. A total of 47 cases had been reported from these five states [14]. As such, a ban was imposed on the import of African rodents of all kinds into the USA. Other than West Africa, the major outbreak in Sudan in 2005 is also noteworthy [15] (Figure 2).

Figure 2: Timeline of Monkeypox Outbreaks as per reports sourced from researchgate.net.

As of now, only two clades of the virus have been found with the help of genomic sequencing and these are WA and CB clades. The clades can be differentiated in virulence [16]. Furthermore, the WA and CB clades have genetic distinction at the same time [17].

Right from the first day of 2022, cases of the virus are being reported to the WHO. By now, a total of 42 Member States have sent reports of confirmed cases spanning five WHO regions. The number of laboratories confirmed cases stood at 2103 by the end of 15th June, 2022 as well as one death.

One look at the travel history reveals tours taken to countries belonging in the European as well as North American regions. As previously stated, none of these regions fall under the endemic zones which suggests that the transmissions may have gone unnoticed prior to the recent chain of events for a while. The highest number of confirmed cases i.e., nearly 85% have originated from the European region. On the other hand, a mere 3% of the cases have originated from the African region whereas American region contributes a total of 12% of the cases.

As new information becomes readily available, it is going to make the case count fluctuate. With that said, the WHO shows complete support in the case of information sharing [18].

Since it has previously established that Monkeypox virus is a rare disease, the diagnosis will be difficult. It is possible for healthcare providers to assume at first that the victim is suffering from other forms of rash illnesses. The healthcare provider will not rule out the possibility of the patient suffering from measles or chickenpox at first instead of Monkeypox. One way to distinguish between the poxes and monkeypox is the sight of swollen lymph nodes.

In order to perform diagnosis on the patient, the healthcare provider is going to take a tissue sample. This can be done by taking the sample from an open sore. The sample will then be sent to a lab that conducts polymerase chain reaction (PCR) testing. Now, PCR is basically genetic finger printing [19].

Other ways of performing a diagnosis are also available for the healthcare provider. For instance, the healthcare provider can simply inquire about the travel history. As such, he will have a better chance of understanding the possible risks you have of contracting the virus. In addition, the healthcare provider can opt for biopsy. If your healthcare provider talks to you about performing a biopsy, it means that they will remove a small portion of your skin tissue to conduct tests for the virus.

With that said, it is unwise to opt for blood tests. The primary reason behind it is that monkeypox virus leaves the blood within a short span of time. Hence, the results of the blood test to diagnose the virus have every chance of turning up incorrect [20].

The road to staying safe from the virus includes a number of priorities for people to follow:

- Rise in vigilance of the healthcare providers to detect cases in time as well as isolating patients along with the prevention of transmission with the help of intensified surveillance.

- Providing health security for the healthcare workers while actively trying to prevent transmission of the virus in any healthcare setting that can achieved through personal protection equipment.

- Enforcing public health measures to reduce the risks such as, encouraging safe gathering as well as bringing positive changes to global collaborations by means of information sharing.

- Implementing risk-based plans to employ countermeasures to add to the public health intervention on the basis of needs, risks as well as benefits consisting of the primary public health interventions.

In addition, the global mechanisms are in need of support to be developed. As such, this will ensure access to useful countermeasures. Hence, these activities are going to hasten the research agenda regarding monkeypox.

With the monkeypox virus, much is still uncertain. Whether the virus will wreak as much havoc as smallpox remains to be seen. The bare minimum still needs to be done in order to remain safe from the virus. While the world economy is coming to terms with the effects of COVID-19, it cannot afford to undergo more lockdowns caused by monkeypox virus. As such, the precautionary measures have to be made available as information to everyone.

We would like to express our gratitude to every one of the interview participants who graciously provided us with the information we needed. This research has been partly supported by a grant from the Ministry of Education and Science (21K07354) in Japan.

The authors declare that they have no conflict of interest.

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