Monkeys shipped to Denmark from Singapore were first reported for the monkeypox virus in 1958. Further outbreaks in captive monkeys were documented in the Netherlands, the USA, and France over the next ten years. Many affected animals died during these outbreaks; however, no human case was reported, suggesting that humans are insusceptible to this virus.
In 1970, nine months after smallpox eradication in the Democratic Republic of Congo (formerly Zaire), the first case of monkeypox in humans was reported in a kid in the equatorial region. In West African nations, between 1970 and 1971, six further cases of monkeypox in humans were reported. Later laboratory-confirmed studies reported that Clade I and Clade II are the two subtypes of the monkeypox virus. Comparing clade I to clade II, a greater proportion of monkeypox patients typically experience severe illness or pass away.
Clade 1 of the monkeypox virus produced multiple epidemics with high death rates (between 1 and 12%) in the Congo for several years. Due to a lack of adequate diagnostic resources in the area, the majority of these cases were not confirmed by the laboratory. Up until 2003, human monkeypox was thought to be exclusively an African disease, when reports of cases outside of Africa began to surface.
In 2003, there was some international attention given to monkeypox as it spread to the USA. In the USA in 2003, monkeypox was brought after a shipment of infected Gambian pouched rats from Ghana to Texas, which subsequently infected prairie dogs kept in the same facility. These dogs further infected 71 individuals who had adopted these animals as pets. Nigeria experienced a significant monkeypox virus clade 2 outbreak in 2017, with 122 PCR-confirmed cases. In 2018, the disease was imported into the UK by two individuals who had visited Nigeria, and a healthcare worker was found to have contracted the secondary infection. Five infected patients were found in 2018—three in Singapore, one in Israel, and three in the United Kingdom.
Clade I
In the DRC, clade I monkeypox is endemic. A newer outbreak in Central and East Africa is caused by clade I monkeypox. The Democratic Republic of Congo (DRC) has recorded over 27,000 suspected cases of monkeypox and over 1,300 deaths since January 2023. In April 2024, a clade I monkeypox outbreak was reported in the Republic of the Congo (ROC), which shares a western border with the Democratic Republic of the Congo (DRC). Along with the Democratic Republic of the Congo (DRC), the Central African Republic (CAR) has also reported confirmed instances of clade I. Although endemic to the ROC and CAR, Clade I monkeypox appears to have spread from the DRC in recent cases. Clade I monkeypox cases were confirmed in Burundi, Rwanda, and Uganda, countries bordering the Democratic Republic of the Congo, towards the end of July 2024. Two cases of monkeypox linked to travel have also been recorded from Kenya.
The epidemic was designated a Public Health Emergency of International Concern (PHEIC) by the World Health Organization (WHO) on August 14, 2024. The WHO has declared a global alert at its highest level, indicating that this virus may pose a threat to nations worldwide. On August 15, 2024, came the announcement of a case of Clade I monkeypox in a Swedish tourist who had traveled to an infected country in Africa. This is the first case of clade I monkeypox outside of Africa that has been documented. On August 22, Thailand declared that a visitor from the Democratic Republic of the Congo had been diagnosed with clade I monkeypox.
Clade II
Beginning in 2022, the endemic West African strain of monkeypox, known as Clade II, spread around the world. A small number of travel-related cases were documented outside of endemic nations in North America, Europe, and Asia between 2003 and 2022.
On May 6, 2022, a man visiting the UK from Nigeria was confirmed to be the first monkeypox case in the ongoing worldwide outbreak. Cases of monkeypox have been recorded in several non-endemic countries since the beginning of May 2022. However, on May 13, 2022, a global outbreak of monkeypox clade 2b led to the declaration of a PHEIC.
More than 1350 laboratory-confirmed cases of monkeypox have been reported as of June 9, 2022, from 31 non-endemic countries worldwide. Of these, almost 60% had been reported from Spain, Portugal, and the United Kingdom. According to the US Centers for Disease Control and Prevention (CDC), there have been 45 cases documented as of June 9, 2022, spread among 15 states and the District of Columbia. On July 23, 2022, the WHO proclaimed a worldwide health emergency.
As of October 7, 2022, in 107 different places across the globe, 71,096 cases of monkeypox infection had been documented, with 70,377 of those cases occurring in nations where monkeypox has never before been reported. The United States has reported the highest number of cases, followed by Brazil and Spain.
The PHEIC was deemed to be over by the World Health Organization in May 2023, citing consistent advancements in containing the disease’s spread. A total of 1,700 cases were reported in 2023. The number of confirmed cases remained relatively low in 2024 as well; as of August 25, 2024, 121 countries had reported 225 deaths and 103,446 confirmed cases.
The National Command and Operation Center (NCOC) of Pakistan announced on August 15, 2024, that there may have been a monkeypox case in the province of Khyber Pakhtunkhwa. The Khyber Pakhtunkhwa health department said on August 17 that two people had tested positive for monkeypox.
On 16 August, Portugal’s Directorate-General of Health (DGS) confirmed that three new cases of monkeypox had been confirmed in the country between May and July 2024. On 17 August 2024, Indonesia’s Independence Day, the national Ministry of Health (Kemenkes) reported a total of 14 confirmed monkeypox cases from January to April 2024. On 19 August 2024, the Philippines’ Department of Health (DOH) announced that a 33-year-old male from Metro Manila, with no prior history of traveling overseas, had tested positive for monkeypox the day prior. The patient was later determined to have contracted clade II monkeypox.
References
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An informative and useful article.
Well done 👌
Well done
Great