2022 Monkeypox Outbreak

An ongoing outbreak of monkeypox, a viral disease, was confirmed in May 2022. The initial cluster of cases was found in the United Kingdom, where the first case was detected in London on 6 May 2022 in a patient with a recent travel history from Nigeria (where the disease is endemic). On 16 May, the UK Health Security Agency (UKHSA) confirmed four new cases with no link to travel to a country where monkeypox is endemic. All four cases appeared to have been infected in London. From 18 May onwards, cases were reported from an increasing number of countries and regions, predominantly in Europe and in the Americas but also in in Asia, in Africa, and in Oceania. The outbreak marks the first time monkeypox has spread widely outside Central and West Africa.

On 23 July, the Director-General of the World Health Organization (WHO), Tedros Adhanom Ghebreyesus, declared the outbreak a public health emergency of international concern (PHEIC). As of 14 November, there had been a total of 79,151 confirmed cases in over 111 countries.

Monkeypox is a viral infection that manifests a week or two after exposure with fever and other non-specific symptoms, and then produces a rash with lesions that usually last for 2–4 weeks before drying up, crusting and falling off. While monkeypox can cause large numbers of lesions, in the current outbreak, some patients experience only a single lesion in the mouth or on the genitals, making it more difficult to differentiate from other infections. In infections before the current outbreak, 1–3 percent of people with known infections have died (without treatment). Cases in children and immunocompromised people are more likely to be severe.

Monkeypox spreads through close, personal, often skin-to-skin contact. The disease can spread through direct contact with rashes, or body fluids from an infected person, by touching objects and fabrics that have been used by someone with monkeypox or through respiratory secretions. Given the unexpected and vast geographical spread of the disease, the actual number of cases is likely to be underestimated. While anyone can get monkeypox, to date the majority of confirmed cases outside of the endemic regions in Africa occurred in young or middle-aged men who have sex with men (MSM) who had recent sexual contact with new or multiple partners. On 28 July, the WHO Director-General advised MSM to limit exposure by reducing the number of sexual partners, reconsidering sex with new partners, and maintaining contact details to allow for epidemiological follow-up. The Centers for Disease Control and Prevention has emphasized the importance of reducing stigma in communicating about the demographic aspects of monkeypox, specifically with regards to gay and bisexual men.

Background

Emergency preparedness

In March 2021, the Nuclear Threat Initiative led a tabletop exercise at the Munich Security Conference simulating hypothetical public health responses to the release of a genetically manipulated strain of monkeypox.

On 23 July 2022, the World Health Organization Director-General Tedros Adhanom Ghebreyesus declared the 2022 outbreak a public health emergency of international concern.

Monkeypox in endemic Africa

The Africa Centres for Disease Control and Prevention had alerted several members of the African Union in May 2022 about cases of monkeypox. The director of the Africa CDC, Ahmed Ogwell, said that Cameroon, Central African Republic, the Democratic Republic of Congo and Nigeria have reported 1,405 endemic cases with 62 deaths during the first five months of 2022. The case fatality rate in these four African countries combined was 4.4%.

In an article in ''The Conversation'', Oyewale Tomori pointed out that the number of monkeypox infections in Nigeria through 2021 is likely to be under-reported because much of the Nigerian population has been avoiding healthcare facilities due to fear of contracting COVID-19. Nigeria's surveillance of various diseases, including monkeypox, had to focus on the global COVID-19 pandemic in 2020 and 2021, missing many cases and resulting in a drop in official statistics. As British health authorities reported the first case of monkeypox in the UK in May 2022, the Nigerian government has released to the public information and statistics on reported cases and deaths in the country. In the report of 9 May 2022, the NCDC stated that 230 cases were confirmed across 20 states and the Federal Capital Territory between 2017 and 2022. Rivers State was the most affected, followed by Bayelsa and Lagos. In the span from 2017 to 2022, the NCDC reported six deaths in six different states, making for a 3.3% case fatality ratio. On 30 May, the first death from monkeypox was reported in Nigeria during 2022; the last time a death was reported in the country from this disease was in 2019.

Outbreak characteristics

Monkeypox is endemic to West and Central Africa. Prior to the 2022 outbreak, the United Kingdom had recorded only seven previous cases of monkeypox, all of which were imported cases from Africa or healthcare workers involved in their treatment. The first three such cases were in 2018, followed by a further case in 2019 and three more in 2021. The only major monkeypox outbreak to be recorded in a Western country prior to 2022 was the 2003 Midwest monkeypox outbreak in the United States, which did not feature community transmission.

Phylogenomic characterization of the first monkeypox virus outbreak genome sequences, found the "presumably slow-evolving" DNA virus has evolved roughly 6–12-fold more mutations than one would expect and 15 SNP mutations since the beginning of the outbreak.

The monkeypox incubation period is estimated to be 8.5 days on average and up to 21 days.

As of June 2022, ring-vaccinations and pre-exposure vaccination of MSM are strategies being advanced in some countries to contain the outbreak. Local transmission leading to sizeable clusters may have gone unnoticed for some time. Two vaccines are currently available. A short review suggests supportive care may typically be sufficient and that several antivirals and vaccinia immune globulin intravenous (VIGIV) are available as treatments. Better understanding of the new monkeypox variant is important for accelerating the development of vaccines and drugs.

The UK Human Animal Infections and Risk Surveillance (HAIRS) group warned that the virus could reach wildlife and become endemic as a result. There is a concern that if the ongoing outbreak is prolonged, it "could establish new ecological niches in wild animals" in regions outside of Africa.

Scientists are investigating circulating lineages (and potential variants) of the monkeypox virus and are comparing them against the African endemic lineages.

In July 2022, scientists reported that the window to be able to contain the outbreak is closing or has closed.

An analysis of studies by a journalist indicates that "about 10-to-15% of cases have been hospitalized, mostly for pain and bacterial infections that can occur as a result of monkeypox lesions". Studies published a month later, in August indicated hospitalizations of small cohorts of early patients were 8% and 13%.

Chronologically

In the beginning of May 2022, a case of monkeypox in a British resident who had travelled to Lagos and Delta State in Nigeria, in areas where monkeypox is considered to be an endemic disease, was reported. The person developed a rash on 29 April while in Nigeria and flew back to the United Kingdom, arriving on 4 May, and presented to hospital later the same day. Monkeypox infection was immediately suspected, and the patient was hospitalised at a specialist clinical unit of the Guy's and St Thomas' NHS Foundation Trust and isolated, then tested positive for the virus on 6 May. Testing of patient swab samples by polymerase chain reaction revealed the outbreak to be of clade II of monkeypox, which is the less deadly of the two known monkeypox variants with a case fatality rate of around 1%. The genomic sequence of the virus associated with this outbreak was first published on 19 May by Portuguese researchers.

Extensive contact tracing of people who had been in contact with the index case both on the international flight from Nigeria to the United Kingdom and within the country following their arrival was carried out, with potential contacts advised to remain aware of the symptoms of monkeypox and immediately isolate if any were to develop within 21 days of the contact event. Following this contact tracing effort, the World Health Organization (WHO) considered further transmission of the virus within the United Kingdom to be of "minimal" risk. Contact tracing was extended to Scotland on 14 May according to Public Health Scotland. A "small number" of people in Scotland were ordered to self-isolate following close contact with the person initially reported to have been infected, although overall risk to the general public remained "very low".

On 12 May two new cases of monkeypox were confirmed by the UK Health Security Agency (UKHSA), both in London, living together in the same household, with no known link between either of them and either the index case or travel to endemic regions. One of the new cases was hospitalised at St Mary's Hospital, while the other case with milder symptoms was said to be self-isolating at home. On 17 May, another four cases of monkeypox were confirmed by the UKHSA in three Londoners and a person in North East England who had previously travelled to London.

Unusually, none of these new cases had any known contact history with the previous three confirmed cases, which suggested a kind of transmission that had not been seen before, a wider community transmission of the virus in the London area. The UKHSA stated that the risk to the general public remained "very low". Patients with active monkeypox infection were confirmed to be hospitalised at the Royal Victoria Infirmary in Newcastle upon Tyne and at the Royal Free Hospital and Guy's Hospital in London.

Also on 20 May, UK Health Secretary Sajid Javid reported that another eleven cases had been confirmed, bringing the total in the country to twenty. UKHSA reported on 10 June that 311 of the 314 cases where sex was known were men, and that all of the 151 infected persons who filled out an additional questionnaire and answered questions about sexual practices were men who have sex with men, abbreviated MSM. Dr. Susan Hopkins from the UKHSA urged watchfulness among men who have sex with men. The UK Health Security Agency (UKHSA) advised people who have had close contact with a person infected with monkeypox to self-isolate for 21 days.

Further cases in multiple countries outside the endemic area were reported through the second half of May 2022. On 18 May, Portugal reported 14 cases of monkeypox. In Spain, there were seven confirmed cases as of 18 May. On the same day, the United States confirmed its first 2022 case of monkeypox and Canada reported 13 suspected cases.

On 19 May, Sweden, Belgium and Italy confirmed their first cases. On 20 May, Australia, Germany, France and the Netherlands confirmed their first cases. For the remainder of May, multiple European countries and Israel confirmed their first cases. The United Arab Emirates and Mexico also confirmed their first cases.

On 23 May, David Heymann, an advisor for the World Health Organization, said that the likely theory of how the outbreak started is transmission during sexual intercourse of gay and bisexual men at two raves in Belgium and Spain. On 25 May, ''The Guardian'' stated that many scientists suspect the disease was circulating across Europe before reaching the MSM community, possibly misdiagnosed or detected only in isolated cases; four cases were diagnosed in 2018 and 2019, all in individuals who recently arrived from Nigeria.

In addition to more common symptoms, such as fever, headache, swollen lymph nodes, and rashes or lesions, some patients have also experienced proctitis, an inflammation of the rectum lining. CDC has also warned clinicians to not rule out monkeypox in patients with sexually transmitted infections since there have been reports of co-infections with syphilis, gonorrhea, chlamydia, and herpes.

Deaths outside of endemic Africa

The first death outside of endemic Africa was reported in Brazil on 29 July 2022, in a 41-year-old man with underlying comorbidities. On the same day Spain reported its first death, a 44-year-old man in Alicante, with the cause of death being encephalitis associated with monkeypox infection. Spain reported its second monkeypox-related death on 30 July 2022, in a 31-year-old man in Córdoba, who had also suffered from encephalitis according to reports. On 1 August 2022 India confirmed its first monkeypox death, a 22-year-old male who died in Thrissur, Kerala on 30 July. On the same day, Peru reported the death of a monkeypox-affected 45-year-old male, who also had HIV and septic shock.

On 30 August 2022 a Texan from Harris County became the first American to die of the monkeypox epidemic.

Transmission

A large portion of those infected had not recently travelled to areas of Africa where monkeypox is endemic, such as Nigeria, the Democratic Republic of the Congo as well as central and western Africa. It is transmitted by close contact with infected people, with extra caution for those individuals with lesions on their skin or genitals, along with their bedding and clothing. The disease can spread via respiratory secretions or by direct contact with rashes, body fluids or by touching objects and fabrics that have been used by someone with monkeypox. The CDC has also stated that individuals should avoid contact and consumption of dead animals such as rats, squirrels, monkeys and apes along with wild game or lotions derived from animals in Africa.

Transmission patterns

The 2022 outbreak initially had a different pattern of spread compared to prior monkeypox outbreaks outside Africa. Genetic evidence suggest the outbreak likely started in Nigeria. Given the unusually high frequency of human-to-human transmission observed in this event, and the probable community transmission without history of traveling to endemic areas, spread of the virus through close contact is more likely, with transmission during sexual activities being the most common route. Most cases have been in men. A significant proportion of cases, although not all, are in men who have sex with men (MSM), notably in Canada, Spain, and the UK, with many cases diagnosed in sexual health clinics. Cases are mostly in young and middle-aged men. This points to transmission due to close contact during sex as being the main route of transmission. In May 2022, the European Centre for Disease Prevention and Control (ECDC) considered the monkeypox virus to be moderately transmissible among humans. According to the centre, among MSM who contracted the virus, the most common means of transmission is likely through sexual activity due to intimate contact with infectious skin lesions. The ECDC rated likelihood of transmission due to close contact, including sexual contact, as "high", but, without close contact, as low. In ''Nature'', Anne Rimoin and Raina MacIntyre speculate that the higher percentage of MSM affected is a result of coincidental introduction to the community and then sexual activity constituting "close contact" rather than the virus itself becoming sexually transmitted. However, in a study published in August 2022, infectious monkeypox virus was able to be isolated from semen samples, and the prolonged shedding of virus in seminal fluids raised the possibility of a genital reservoir for human monkeypox.

On 21 July, a study on a sample of 528 infections diagnosed between 27 April and 24 June outside endemic regions in Africa indicated that: 99% cases were in men; 98% of cases occurred in the community of men who have sex with men (MSM), mainly those who have multiple sex partners (median of 5 partners in the previous 3 months); 75% were white; 41% had HIV/AIDS, of which 96% were on antiretroviral therapy, while 57% of the persons who were not known to have HIV infection were on pre-exposure prophylaxis; 29% had another concomitant sexually transmitted infection; and in the previous month, 32% attended a sex on premises venue and 20% engaged in chemsex.
On 2 August, data collected by the Joint ECDC-WHO Regional Office for Europe Monkeypox Surveillance indicated that 99% (15,439/15,572) of the cases reported throughout the European region were among males, with 44% among MSM, 1% among heterosexuals and another 55% in males whose sexual orientation is unknown. Among cases with known HIV status, 36% (2,690/7,487) were HIV-positive. Updated frequently.

A preprint suggests that cases "where a small fraction of individuals have disproportionately large numbers of partners, can explain the sustained growth of monkeypox cases among the MSM population".

The reproduction number during the initial phase of the 2022 global outbreak of monkeypox was estimated to be 1.29.

As the monkeypox outbreak developed, nosocomial and other forms of human-to-human spread became apparent, with a notable example being a doctor in an Israeli hospital becoming infected probably while removing protective clothing after examining monkeypox patients. Contaminated surfaces within hospitals and households may be infectious, with widespread contamination of surface and air samples taken from monkeypox isolation rooms in UK hospitals being documented.

In August, the first known case of probable human-to-dog transmission was reported with the canine exhibiting very similar signs and symptoms of monkeypox infection to that of humans. A preprint indicates there can be (rare) asymptomatic infections.

Wastewater surveillance

A study from the Faculty of Medicine, Chulalongkorn University, reported Multiple traces of monkeypox were detected in non-sewered wastewater with sparse sampling collected from both the Bangkok, Thailand with increasing concentrations from June to August 2022. This is the first dataset related to Monkeypox viral DNA in wastewater in Bangkok. Monkeypox viral DNA was first detected in wastewater in the second week of June 2022. From the first week of July, the number of viral DNA copies increased. Sanger sequencing confirmed the identification of the monkeypox virus and its relation to the 2022 monkeypox outbreak.

Statistics

Total confirmed cases outside of endemic Africa

New cases, per day outside of endemic Africa

Total confirmed deaths outside of endemic Africa

New deaths per day, outside of endemic Africa

Vaccination

Smallpox vaccines containing vaccinia such as Imvanex (Jynneos) and ACAM2000 can provide around 85% effectiveness against monkeypox. This protection level is calculated from studies using smallpox vaccines tested in late 1980 in Africa. According to the CDC the vaccination with Jynneos/Imvanex is " ministered as two subcutaneous injections four weeks apart." while the vaccination with ACAM2000 is "administered as one percutaneous dose via multiple puncture technique with a bifurcated needle." However, ACAM2000 is not recommended for potentially immunocompromised persons due to high replication competency of vaccinia while Imvanex (Jynneos) is recommended for potentially immunocompromised persons due it containing an attenuated, non-replicating orthopoxvirus, Modified Vaccinia Ankara-Bavarian Nordic (MVA-BN). The UKHSA has begun using Imvanex as post-exposure prophylaxis for close contacts of known cases.

On 25 May, disease experts from the NICD in South Africa said they saw no need for mass vaccination, because they believe cases will not explode as they did in the COVID-19 pandemic.

In reaction to the current outbreak of monkeypox, a number of countries have stated they are buying vaccines and/or releasing vaccines from national stockpiles for use in the outbreak. In May 2022, the US, Spain, Germany and the UK all announced purchases of smallpox vaccine.

On 24 May, Centers for Disease Control (CDC) Deputy Director Jennifer McQuiston confirmed the United States is releasing some of their Jynneos vaccine supply from their Strategic National Stockpile for people who are "high-risk".

On 23 June, the New York City Department of Health announced a clinic at the Chelsea Sexual Health Clinic would offer the two-dose Jynneos vaccine to "...all gay, bisexual, and other men who have sex with men (cisgender or transgender) ages 18 and older who have had multiple or anonymous sex partners in the last 14 days." By July 27, the federal government had distributed 300,000 doses to state and local health authorities, with distribution at clinics nation-wide, and was planning to release 786,000 more that week.

Bavarian Nordic is the only manufacturer of Jynneos in the world, and its manufacturing facility closed in spring 2022 to be refitted to make vaccines for other diseases using the MVA-BN technology. The company projects Jynneos manufacturing will restart in 2023, except for 15 million doses that just need final "fill and finish" repackaging.
The United States helped fund the development of Jynneos, leading to concerns that existing contracts will lead to vaccine nationalism and hoarding, and prompting calls for allocating doses to lower-income countries via GAVI.Exclusive: Closure of World’s Only Manufacturing Plant for Monkeypox Vaccine Raises Questions About World's Ability to Meet Rising Demand
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On 9 August, the FDA gave emergency use authorization for intradermal (rather than subcutaneous) monkeypox vaccination using a lower dose of Jynneos, which would increase the number of available doses up to five-fold. The vaccination would still be given in two doses, 28 days apart. A 2015 study had tested a regimen of one-fifth dose given intradermally.

Another monkeypox vaccine, the modern LC16m8 vaccine was developed in Japan as a national asset, and the manufacturer said it could not assist other countries.

Social aspects

As of May 2022, public health authorities have aimed to target resources and education to affected groups, but avoid stigma which could discourage people with symptoms or who have been exposed from seeking help. LGBT rights groups have issued statements advising media to avoid stigmatising marginalised groups such as men who have sex with men. On 22 May, UNAIDS urged communicators to avoid stigma by taking an evidence-based approach, reiterated that the disease can affect anyone and that risk is by no means limited to men who have sex with men.

On 24 May, ''The Washington Post'' published an article that pointed out the lack of global attention to the disease when it only affected Africans, compared to the attention directed at it when a small number of cases started affecting Western countries. Some also objected to pictures used in media coverage of mild illnesses in Europe that featured severe cases in sub-Saharan Africans.

On 26 July, Owen Jones of ''The Guardian'' argued that the focus needs to be on testing, awareness and vaccination, that targeted health messages help protect as many people as possible from the virus, and that those most at risk should be protected without stigma, noting that some members of the LGBT community have already started to adjust behaviors to reduce risk.

On 30 July, Rod Dreher of ''The American Conservative'' criticized public health officials for not shutting down gay sex clubs in response to the outbreak. Similarly, many conservative commentators have accused public health officials of hypocrisy for implementing harsh restrictions on everyday life in response to the COVID-19 pandemic while not encouraging similar restrictions in response to monkeypox, such as shutting down sex parties and practicing abstinence. In response, public health officials have "reject dcomparisons to the early days of the coronavirus pandemic, when they mandated masks and shut down public spaces. They noted that the novel coronavirus was unfamiliar, far deadlier and airborne, with hospitals overrun with patients at various points over the past two years." and that "Monkeypox has known treatments and vaccines, although they have been challenging to access; it also has not killed anyone in the United States, and hospitalizations are uncommon."

An August survey by the CDC found that gay and bisexual men have significantly reduced sexual encounters in response to the monkeypox outbreak.

Misinformation

Misinformation and conspiracy theories spread online in various social media networks. In an article published by the BBC
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