Overview of Monkeypox

Monkeypox is a rare disease that is caused by infection with monkeypox virus. This virus belongs to the Orthopoxvirus genus in the family Poxviridae. The Orthopoxvirus genus also includes variola virus (the cause of smallpox), vaccinia virus (used in the smallpox vaccine), and cowpox virus. Monkeypox, just like the smallpox developed like other known pox-forming diseases (pustules that eventually break open, ulcerate, crust over, and some pox form scars in the skin

Monkeypox was first discovered in 1958 when two outbreaks of a pox-like disease occurred in colonies of monkeys kept for research, hence the name ‘monkeypox.’ The natural reservoir of monkeypox remains unknown. However, African rodent species are suspected to play a role in transmission.

Human monkeypox was first identified in humans in 1970 in the Democratic Republic of Congo (then known as Zaire) in a 9 -year -old boy in a region where smallpox had been eliminated in 1968. Since then, the majority of cases have been reported in rural, rainforest regions of the Congo Basin and western Africa, particularly in the Democratic Republic of Congo, where it is considered to be endemic. In 1996–97, a major outbreak occurred in the Democratic Republic of Congo. Since then, monkeypox has been reported in humans in other Central and Western African countries.

There are two different genetic groups (clades) of monkeypox virus, i.e. the Central African and Western African. Human infections with the Central African monkeypox virus clade are typically more severe compared to those with the West African virus clade, and thus have higher mortality ratio. Person – to – person sporadic cases is recorded for Centraal African monkeypox virus and limited with the West African monkey pox virus

In the year 2003, monkeypox cases were confirmed in the United States of America (47 cases), marking it the first reported occurrence of the disease outside of the African continent. Most of the patients were reported to have had close contact with pet prairie dogs that were infected by African rodents that had been imported into the country. Soon afterwards, other cases were recorded both in the United Kingdom (3 cases) and Israel (1 case) in 2018. Sporadic cases of monkeypox have been reported from West and Central African countries, and with increasing awareness more countries are identifying and reporting cases. Since 1970 human cases of monkeypox have been reported from 10 African countries – Democratic Republic of the Congo, Republic of the Congo, Cameroon, Central African Republic, Nigeria, Ivory Coast, Liberia, Sierra Leone, Gabon and South Sudan.

Monkeypox Epidemic in Nigeria

Nigeria first experienced her first case of human monkeypox in the year 1971, and a second case was reported, 1978 (1 case).

In 2017 Nigeria experienced the largest documented outbreak, approximately 40 years since the country had last confirmed cases of monkeypox.  Between Sept. 22, 2017, and Sept. 16, 2018,122 confirmed or probable cases were reported from 17 states. There were seven deaths, a 6% case fatality rate. Infected individuals were aged between 2 days and 50 years, and 69% were male. These 122 patients had vesiculopustular rash, and it was also common to see fever, pruritus, headache and lymphadenopathy.mon

According to reports from the Nigeria Centre for Disease Control (NCDC), as at the end of September 2019, 15 new suspected cases of the monkeypox virus has been reported in 6 states – Lagos (5), Rivers (2), Akwa Ibom (3), Zamfara (1), Delta (1), Imo (2) and Federal Capital Territory, FCT (1). Five of these 15 fifteen suspected cases has been confirmed positive for monkeypox in three states – Lagos (3), Rivers (1) and Akwa Ibom (1).

 Five of the suspected cases tested positive for chickenpox while others are for further evaluation.

Although no death recorded in the during that time, yet a total of 81 suspected cases have been reported so far in 2019 of which 39 confirmed cases were recorded in nine states (Bayelsa, Lagos, Delta, Rivers, Akwa Ibom, Enugu, Anambra, Cross River, and Oyo) and one death

Of the confirmed cases, 59% are from two states, Delta (28%) and Lagos (26%). The most affected age-group is 21-40 years (Range: 15-51years, median age: 32 years); 84.6% of confirmed cases are male (male to female ratio = 2.6:1).

Since the beginning of the outbreak in September 2017, a total of 176 confirmed cases and nine deaths have been recorded in 18 states (Rivers, Bayelsa, Cross River, Imo, Akwa Ibom, Lagos, Delta, Bauchi, FCT, Abia, Oyo, Enugu, Ekiti, Nasarawa, Benue, Plateau, Edo, Anambra)

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