Monkeypox – what should we be aware of?

As you have probably heard, people are getting sick all over the world, and several new cases of monkeypox infection have been identified, and people are seriously wondering what the disease is. Let's find out what is known and what the specialists recommend.

Fig. 1: Clinical manifestation of Monkeypox disease

(https://www.nationalgeographic.com)

?Monkeypox is now a disease that impacts worldwide public health because it affects countries around the world:

Fig. 2. Geographical distribution of confirmed and suspected cases of monkeypox worldwide

(https://www.aljazeera.com)

Non-endemic countries

2022??

?During this month (May) multiple cases of monkeypox were discovered in non-endemic countries such as Australia, Belgium, Canada, France, Germany, Italy, the Netherlands, Portugal, Spain, Sweden, the United Kingdom, the United States, Austria, Denmark, Israel, Scotland, and Switzerland;

Cases of monkeypox have been reported to WHO from 12 Member States that are not endemic to the monkeypox virus since May 13, 2022. Epidemiological investigations are ongoing; however, no recorded cases have been linked to endemic areas. According to current data, instances have been detected primarily, but not solely, among males who have sex with men seeking care in primary care and sexual health clinics;

More than 90 laboratory-confirmed cases and more than 20 suspected cases of monkeypox with investigations underway had been reported to WHO from non-endemic states to monkeypox virus as of 21 May;

No associated deaths have been reported to date, and all cases whose samples were confirmed by PCR were found to be infected with the West African lineage;

Studies are currently underway to better understand the epidemiology, sources of infection, and transmission patterns of monkeypox, and the WHO continues to receive updates on the status of ongoing reports of monkeypox cases in endemic countries via established surveillance mechanisms (Integrated Disease Surveillance and Response). For example, more cases were confirmed in Canada on May 25 than this table showed between May 13 and 21. (a total of 16 cases of monkeypox).?

Table 1.?Cases of monkeypox in non-endemic countries were reported to WHO between 13 to 21 May 2022 as at 13:00

(https://www.who.int)

2021 ??

Monkeypox has also been reported in travellers from Nigeria to the United Kingdom in May 2021, as well as IN the United States of America in July and November 2021;

2019 ??

There have also been recorded cases of Nigerian travellers in the United Kingdom in December 2019 and Singapore in May 2019;

2018???

Among travellers from Nigeria to Israel and to the United Kingdom in September 2018 have been reported monkeypox cases;

2003???

The first outbreak of monkeypox outside of Africa occurred in the United States of America, and it was linked to contact with infected pet prairie dogs. These pets were kept with Gambian pouched rats and dormice that had been imported from Ghana. This outbreak resulted in about 70 cases of monkeypox in the United States.

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Endemic countries

Benin, Cameroon, the Central African Republic, the Democratic Republic of the Congo, Gabon, Ghana (identified in animals only), C?te d'Ivoire, Liberia, Nigeria, the Republic of the Congo, and Sierra Leone are among the nations where monkeypox is endemic. Benin and South Sudan have previously documented imports. Cameroon and Nigeria are currently reporting cases of the West African clade.

Table 2.?Cases of monkeypox in endemic countries between 15 December 2021 to 1 May 2022

(https://www.who.int)

What is monkeypox?

Monkeypox is a zoonotic disease (transmitted to humans from animals) caused by the monkeypox virus, with symptoms similar to but less severe than smallpox (fever and rash). In 1958, the virus was discovered in monkey colonies hosted for research in a Danish laboratory, and it was eventually identified in rodents as well. The monkeypox virus causes a wide range of clinical symptoms, from asymptomatic to severe illness and even death.

Monkeypox virus is an enveloped double-stranded DNA virus that belongs to the Poxviridae family's Orthopoxvirus genus. Variola virus (which causes smallpox), vaccinia virus (used in the smallpox vaccine), and cowpox virus are all members of the Orthopoxvirus genus. The monkeypox virus has two separate genetic clades: the West African (Sierra Leone, Liberia, Nigeria, etc.) clade and the Central African (Congo Basin) clade. Historically, the Congo Basin clade caused more severe illness and was thought to be more transmissible. Monkeypox is generally found in central and western Africa, particularly near tropical rainforests, and has been increasingly seen in metropolitan settings. The first case outside of the jungle was reported in 2003 in the USA.

Fig. 3. ?Monkeypox clades

(https://www.who.int)

Transmission

Several animal species have been described as being susceptible to the monkeypox virus, including rodents and non-human primates. The natural history of the monkeypox virus is still unclear, and further research is needed to discover the specific reservoir(s) and how virus circulation is maintained in nature.

Primary infection - animal-to-human (zoonotic) transmission - can occur through direct contact with infected animals' blood, body fluids, or cutaneous or mucosal lesions. Evidence of monkeypox virus infection has been detected in several animals in Africa, including rope squirrels, tree squirrels, Gambian poached rats, dormice, various monkey species, and others. Consuming undercooked meat and other animal products from infected animals may present a risk. People who live in or near forested regions may be exposed to infected animals in an indirect or low-level manner. The source of infection is largely unknown.

?Secondary infection, or human-to-human transmission, can occur through close contact with an infected person's respiratory secretions, skin lesions, or recently contaminated objects. Droplet respiratory particle transmission typically involves prolonged face-to-face contact, placing health workers, household members, and other close contacts of active cases at greater risk. However, in recent years, the longest documented chain of transmission in a community has increased from 6 to 9 successive person-to-person infections. Transmission can also occur through the placenta from mother to fetus (resulting in congenital monkeypox) or through intimate contact during and after birth. While intimate physical contact is a well-known risk factor for transmission, the exact mechanism is unknown.

Fig. 3. Monkeypox transmission

(https://www.aljazeera.com)

Signs and symptoms

Monkeypox is a self-limiting viral disease that can last up to 4 weeks. The virus enters the body through open wounds, the respiratory tract, or mucous membranes (e.g., eyes, nose, or mouth). Monkeypox has an incubation period of 6 to 13 days (from infection/exposure to the beginning of symptoms), however, it can range from 5 to 21 days. As a result, a suspect must be followed for up to three weeks. Monkeypox is often a mild infection that resolves on its own after a few weeks. However, in some cases, people can become very ill and die. Severe instances are more common in young people and are associated with the extent of viral exposure, patient health, and other factors.

The infection can be divided into two stages:

1.????The prodromal stage (0–5 days):

·?????acute onset of fever (>38.5oC);

·?????chills;

·?????intense headache:

·?????lymphadenopathy (swelling of the lymph nodes) – pathognomonic - ?distinctive feature in compared to other diseases that may initially appear similar (chickenpox, measles, smallpox);

·?????joint paint – mostly back pain:

·?????myalgia (muscle pain):

·?????intense weakness – lack of energy.

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2.????The rash ?stage - 1–3 days, or longer, after the appearance of fever:

·?????start as macules (lesions with a flat base) then evolve to papules (slightly raised firm lesions), vesicles (lesions filled with clear fluid), pustules (lesions filled with pus - yellowish fluid), and crusts ?(called scabs) which dry up and fall off.

·?????Areas affected:

o??starts in the face and extremities (affects the palms and the soles – characteristic)

o??less affected areas: oral mucous membranes – mouth (in 70% of cases), genitalia (30%), and conjunctivae (20%), as well as cornea;

·?????the number of lesions varies from a few to several thousand painful lesions;

·?????in severe cases, lesions can coalesce until large sections of skin slough off;?

it may take up to 4 weeks for crusts/scabs to dry off and disappear;

·?????a person can be contagious and spread the virus 1 to 5 days before the rash develops and can continue to be contagious until the scabs have fallen off on their own and the skin is healed.

Secondary infections, bronchopneumonia, sepsis, encephalitis, and corneal infection with subsequent vision loss are all possible complications of monkeypox. It is uncertain how widespread asymptomatic infection can be.

?The case fatality ratio of monkeypox has historically ranged from 0 to 11 % in the general population and has been higher among young children. In recent times, the case fatality ratio has been around 3–6%.?

Fig. 4. Monkeypox signs and symptoms

(https://www.aljazeera.com)

Diagnosis

Monkeypox is diagnosed based on a number of factors, including:

·?????risk factors such as exposure to a case and travel history;

·?????signs and symptoms;

·?????laboratory testing.

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A clinical differential diagnosis must be done before a clear picture may be formed:

·?????other rash associated with fever illnesses: ?

o??varicella - chickenpox – herpes virus with blister-like lesions;

o??measles;

o??smallpox (eradicated);

o??bacterial skin infections;

o??scabies;

o??syphilis;

o??medication-associated allergies.

Lymphadenopathy during the prodromal stage of illness can be a clinical feature to distinguish monkeypox from chickenpox or smallpox.?

Fig. 4. Monkeypox clinical features compared to other rash associated with fever illnesses

(https://www.who.int)

?When monkeypox is suspected, it must be confirmed in a laboratory. Because of its precision and sensitivity, the polymerase chain reaction (PCR) test is the primary laboratory test. Health workers should collect an appropriate sample (skin lesions – the roof or fluid from vesicles and pustules, and dry crusts) and transport it safely (packaged and shipped in accordance with national and international requirements) to an appropriate laboratory while wearing personal protective equipment. A biopsy is an option where possible.

?Management

Monkeypox symptoms are usually mild and self-limiting resolving within a few weeks without the need for treatment. Although severe cases and mortality are uncommon, they can occur. If you are feeling extremely ill, you should seek medical attention as soon as possible.

Treatment for monkeypox disease is mainly supportive and focused in manage complications and preventing long-term sequelae. There are no well-established treatments for monkeypox, and there are very limited data available on the clinical effectiveness of specific treatments for monkeypox infection in humans.

Adequate hydration and nutrition are essential. Secondary bacterial infections should be treated according to the recommendations. Those who are infected should treat their rash or sores by letting them dry out if possible or covering them with a dressing to protect the area. People who are infected and those who are not should avoid touching any lesions. As long as cortisone-containing products are avoided, mouth rinses and eye drops can be utilized.

Based on results from animal and human research, the European Medical Association (EMA) licenced tecovirimat (TPOXX), an antiviral drug designed for smallpox, for monkeypox in 2022. It is not widely available yet. Vaccinia immune globulin (VIG) may be recommended for severe cases.

Fig. 5. Monkeypox management

(https://www.aljazeera.com)

Vaccination

Several observational studies have shown that smallpox vaccination is about 85 % effective in preventing monkeypox. As a result, previous smallpox vaccination may result in a milder illness. Although immunization against smallpox was effective, people under the age of 40 to 50 (depending on the country) may now be more vulnerable to monkeypox due to the global stoppage of smallpox vaccine campaigns following the disease's eradication. Some laboratory or health workers may have received a more recent smallpox vaccine to protect them from orthopoxviruses in the workplace. In 2019, a newer vaccine based on a modified attenuated vaccinia virus (Ankara strain) was approved for monkeypox prevention. This is a two-dose vaccine with limited availability. Because of the cross-protection given by the immune response to orthopoxviruses, smallpox and monkeypox vaccines are created in formulations based on the vaccinia virus.

Prevention

The main prevention strategy for monkeypox is to raise awareness of risk factors and educate people about the steps they may take to decrease their exposure to the virus. Scientific research is currently being conducted to determine the feasibility and suitability of vaccination for the prevention and control of monkeypox. Some countries have policies in place or are in the process of adopting policies to provide vaccines to people who may be at risk, such as laboratory staff, rapid response teams, and health workers.

Reducing the risk of zoonotic transmission

Most?human?infections?have?resulted?through?primary,?animal-to-human transmission over time.Contact?with?wild?animals,?especially?those?that?are?sick?or?dead,?must?be?avoided,?including?their?meat,?blood,?and?other?parts.?Furthermore,?before?eating?any?items?containing?animal?meat?or?parts,?they?must?be?thoroughly?cooked.?

Preventing?monkeypox?through?animal?trade?regulations?Some?countries?have?set?restrictions?on?the?importing?of?rodents?and?nonhuman?primates.Captive?animals?that?may?be?infected?with?monkeypox?should?be?isolated?from?other?animals?and?quarantined?immediately.Any?animals?that?have?come?into?touch?with?an?infected?animal?should?be?quarantined,?treated?with?care,?and?monitored?for?monkeypox?signs?for?30?days.

Reducing the risk of human-to-human transmission

For outbreak containment, surveillance and early detection of new cases are crucial. Close contact with sick people is the major risk factor for monkeypox virus infection during human monkeypox outbreaks. Health workers and household members are more vulnerable to infection. Health professionals who care for patients with suspected or confirmed monkeypox virus infection, or who handle specimens from them, should follow standard infection control precautions. Persons who have already been immunized against smallpox should be chosen to care for the patient if possible.

Samples collected from people and animals suspected of having monkeypox virus infection should be handled by competent personnel working in properly equipped laboratories. According to WHO guidelines for the transport of infectious substances, patient specimens must be safely prepared for transport with triple packaging.

The discovery of clusters of monkeypox patients in numerous non-endemic countries in May 2022, with no direct travel linkages to an endemic location, is unusual. More research is being conducted to establish the likely source of the infection and to control its spread. While the origins of this outbreak are being explored, it is critical to consider all possible mechanisms of transmission in order to protect public health.

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Resources:

·?????https://www.who.int/news-room/fact-sheets/detail/monkeypox - accessed on 26 of May 2022;

·?????https://www.who.int/emergencies/disease-outbreak-news/item/2022-DON385?fbclid=IwAR07rvVd4C7D8ZpRVHm0rDrppZoM_y2qWU67KiGa3JqPoOEAMh3A6xKqUKQ - accessed on 26 of May 2022;

·?????https://www.canada.ca/en/public-health/services/diseases/monkeypox.html - accessed on 26 of May 2022;

·?????https://www.cdc.gov/poxvirus/monkeypox/index.html- accessed on 26 of May 2022;

·?????https://www.canada.ca/en/public-health/news/2022/05/update-on-monkeypox-in-canada--may-25-2022.html- accessed on 26 of May 2022;

·?????https://theconversation.com/what-is-monkeypox-a-microbiologist-explains-whats-known-about-this-smallpox-cousin-183499?fbclid=IwAR2_7qct5_qW9Dp4kwP_-cjovFrXTQAWY7KlOm0T53JT38u5XKgsWBATpdo- accessed on 26 of May 2022;

·?????https://www.aljazeera.com/news/2022/5/24/map-where-has-monkeypox-been-detected-so-far- accessed on 26 of May 2022.