January 2, 2020 UPDATE: Monkeypox is an ongoing health risk in Nigeria and the Democratic Republic of Congo; currently there are monkeypox outbreaks in both countries. In addition, health officials from three different countries have reported five cases of monkeypox in travelers coming from Nigeria since late 2018. In November, British authorities diagnosed a traveler from Nigeria with monkeypox in the United Kingdom; this is the third such case. OSAC is reissuing this report from 2017 in the midst of a new outbreak of monkeypox, a rare and potentially deadly disease that manifests in disfiguring skin lesions, and for which there is no treatment. The U.S. Centers for Disease Control & Prevention (CDC) issued updated Travel Health Notices for both countries on January 2. For more information on how monkeypox could affect travelers, read this OSAC health snapshot.
October 25, 2017
As of October 20, the World Health
Organization (WHO) was investigating 86 suspected cases of
monkeypox in 11 states across Nigeria. The WHO Regional Laboratory in Senegal
has so far confirmed three cases of monkeypox. While there has been one related
suicide, there have been no disease-related deaths. Monkeypox is a rare disease
that manifests in disfiguring skin lesions, and for which there is no
Minister of Health is also working to discount circulating rumors, especially
in Bayelsa state, that the military is intentionally spreading monkeypox
through vaccinations. Contrary to these rumors, any vaccination efforts in
Nigeria are undertaken by state governments and the federal Ministry of Health,
not the military; additionally, no vaccine exists for the disease.
WHAT IS MONKEYPOX?
is a rare disease caused by infection with monkeypox virus, which belongs to
the same genus as smallpox. The illness
begins with fever, headache, muscle aches, backache, swollen lymph nodes,
chills, and exhaustion. Within 1 to 3 days (sometimes longer) after presentation
of fever, the patient develops a rash, often beginning on the face then
spreading to other parts of the body. The illness typically lasts for 2−4
There are two distinct genetic groups of the virus -- Central
African (or Congo Basin) and West African – that do not geographic overlap geographically, as major rivers provide
physical boundaries that prevent transmission between the potential carrier
populations. West African monkeypox is associated with milder disease, fewer
deaths, and limited human-to-human transmission. Case fatality in
monkeypox outbreaks has been between 1% and 10%, with most deaths occurring in
younger age groups.
The natural reservoir of monkeypox remains unknown; however,
rodents may play a role in transmission.
WHERE IS IT BREAKING OUT?
The first recorded human case of monkeypox was in 1970 in the
Democratic Republic of Congo (DRC). The majority of reported cases have
been in rural, rainforest regions of the Congo Basin and western Africa,
particularly in the DRC, where it is endemic. Nigeria has had two previous
instances of monkeypox: in 1971 (2 cases) and 1978 (1 case). A 2003 outbreak in
the U.S. was the only instance of monkeypox infections in humans documented
outside of Africa.
current outbreak began in Yenagoa, Bayelsa state, on September 22. Only three
monkeypox cases have been confirmed so far, all in Bayelsa. Suspected cases in
the current outbreak have been reported in Akwa Ibom, Bayelsa, Cross River,
Delta, Ekiti, Enugu, Imo, Lagos, Nasarawa, and Rivers states, and the Federal
Capital Territory (see attached map). These states are mostly in the southern
part of Nigeria. All four suspected cases in Lagos and both suspected cases in Abuja have been confirmed negative for
monkeypox. There are no confirmed cases in either city. The Minister of Health
said he expects that many of the suspected cases elsewhere are also not
monkeypox but did not speculate further.
WHEN DOES IT OCCUR?
There are three potential explanations for the most recent
outbreak of monkeypox in southern Nigeria:
The Delta State Coordinator of the WHO, speaking in Abuja to
the Association of Medical Scientists of Nigeria, suspected the outbreak was exacerbated by regional flooding. He posited, “floodwater
was a major source of infectious communicable diseases because animals defecate
in floodwater, which humans come in contact with.” Specifically, he suggested,“For
floods…lasting for one to four weeks, expect rodent-borne diseases...” The
National Coordinator of the NCDC identified flood-prone areas as Rivers, Benue,
and Niger states, and the coastal areas of Akwa Ibom, Adamawa, Bayelsa, Cross
River, Jigawa, Kaduna, and Lagos states, many of which overlap with the current
monkeypox outbreak .
Another theory is that humans may have had exposure to
multiple infected monkeys or rodents across a broad geographic area.
A final theory is that since the eradication of
smallpox and the cessation of vaccination programs, populations in areas prone
to pox outbreaks may have a decreased immunity, allowing Orthopox
viruses such as monkeypox to infect people.
WHO DOES IT IMPACT?
Transmission of monkeypox virus occurs when a person makes
contact with the virus from an animal, human, or material contaminated with the
virus. The virus enters the body through broken skin (even if not visible),
respiratory tract, or the mucous membranes.
Animal-to-human transmission may occur by bite or scratch, bush meat
preparation, direct contact with body fluids or lesion material, or indirect
contact with lesion material. In Africa, human infections have been
documented through the handling of infected monkeys or rodents, with the latter
being the major reservoir of the virus. Eating inadequately cooked meat of
infected animals is a possible risk factor.
Human-to-human transmission is thought to occur primarily through
large respiratory droplets-- sneezing. However, transmission would require
close and prolonged contact. Other human-to-human methods of transmission
include direct contact with body fluids or lesion material or indirect contact
with lesion material (ie. contaminated clothing or linens). Human-to-human
transmission is has only been documented in the Central African strain of monkeypox.
Still, precautions are needed to mitigate the potential human-to-human
transmission. The Minister of Health advised that “health care workers are strongly
advised to always practice universal precautions while handling patients and/or
body fluids at all times. They are also urged to be alert, be familiar with the
symptoms of monkey pox and maintain a high index of suspicion.”
WHY SHOULD I BE
Monkeypox is a very rare disease. This current outbreak seems
to be the West Africa strain, for which human-to-human transmission has not
been documented, underscoring that the caseload is likely to remain relatively
low. There is no treatment or vaccine available.
is self-limiting, meaning that it generally resolves without treatment.
Monkeypox is in the same genus as smallpox, likely
protecting those who received the
smallpox vaccine from getting monkeypox, or at least making it more likely they
experience a less severe case. Past data from Africa suggests that having
received the smallpox vaccine is at least 85% effective in preventing
monkeypox. Smallpox, however, was eradicated in the 1980s and routine public vaccination against smallpox was no longer needed.
HOW DO I RESPOND?
In an effort to raise awareness on the risk factors, the
National Youth Council of Nigeria announced a nationwide campaign, “Kick Monkey pox out of Nigeria,”
on October 23. The program will address prevention measures, vaccinations, and
WHO is supporting Bayelsa state in rumor
control efforts, contact tracing, and containment of any further spread of the
human-to-human monkeypox outbreaks, close contact with other patients is the
most significant risk factor for monkeypox infection. According to the
U.S. Centers for Disease Control and Prevention (CDC), there are number of
measures to prevent infection with monkeypox
Avoid contact with animals that could harbor the virus (including sick
animals or those found dead in areas where monkeypox occurs).
Avoid contact with any materials, such as bedding, that has been
in contact with a sick animal.
Isolate infected patients from others who could be at risk for
Practice good hand hygiene after contact with infected animals or
humans. For example, washing your hands with soap and water or using an
alcohol-based hand sanitizer.
Use personal protective equipment when caring for patients.
more information on this or other security issues in West & Central Africa,
contact OSAC’s Africa Team.
Consider the following external resources on Monkeypox:
CDC Monkeypox page
o Travel Health
Notice: Nigeria (Watch Level 1: Practice Usual Precautions)
Health Notice: Democratic Republic of Congo (Watch Level 1: Practice Usual
WHO Monkeypox Sheet