The World Health Organization on August 14 considered that the increase in cases of mpox (better known as monkeypox) in the Democratic Republic of the Congo (DRC) and in a growing number of African countries constitutes a public health emergency of international concern. The decision is important: it is the highest level of alarm, according to international health law.
This means that all countries must take urgent, coordinated action at a global level to prevent the spread of the disease, ensure the health security of affected countries and protect public health worldwide. WHO has committed to coordinating a global response in the coming days and weeks.
The WHO’s decision comes hours after the Africa Centers for Disease Control and Prevention (CDC) declared a continental public health emergency on August 13. All eyes of the world are on the Democratic Republic of the Congo. Last year, reported cases there increased significantly, and so far, the number of confirmed cases this year has already surpassed last year’s total, with more than 15,600 cases and 537 deaths.
This is not the first time that monkeypox has caused this kind of alarm. Nor is it, at least in principle, a pathogen unknown to humanity. Monkeypox is an infection of zoonotic origin caused by a virus of the Orthopoxvirus genus. The first human case was reported in the Democratic Republic of the Congo in 1970, in a 9-month-old child. Since then, it has gradually emerged in Central, Eastern and Western Africa following the eradication of smallpox in 1980 and the end of smallpox vaccination worldwide. In 2022, however, this disease took on a different dimension when it caused a global outbreak that forced the WHO to declare an emergency.
That outbreak ended on May 10, 2023, but it left a trail of cases and a panorama that authorities continued to monitor. During the course of the outbreak, some 59,343 cases of mpox were reported in the Americas with 114 deaths. Of all the cases with information, 96% were men, 84% self-identified as men who have sex with men, and 59% were people with HIV. But if monkeypox is a known virus and has already caused an international emergency, why is it now back at the center of concerns?
The key differences
In September 2023, a cluster of mpox cases were detected in Kamituga Health Zone, a densely populated mining area in South Kivu province, eastern Democratic Republic of the Congo. Between 29 September 2023 and 29 February 2024, provincial surveillance authorities in South Kivu recorded 241 suspected cases meeting the national definition of monkeypox. The majority of cases (93%) occurred in Kamituga Health Zone. Sequencing of six cases in January 2024 revealed a divergent lineage from clade I.
There are two distinct genetic clades of monkeypox virus, i.e., for simplicity, two variants that differ genetically from each other. Clade II, largely confined to West Africa until the global epidemic in 2022, causes less severe disease and a mortality of less than 4%. Clade I, mainly present in Central Africa, and especially in the Democratic Republic of the Congo (DRC), is associated with severe clinical symptoms and higher mortality (which can range from 4% to 11% of cases).
All confirmed cases in South Kivu had a rash and fever. But the new lineage identified by the researchers increased the known diversity of clade I by an additional 54%, the scientists said in a study published last June in the journal Nature.
What this means, in simpler terms, is that the newly identified lineage not only expands the range of genetic variation within clade I, but also suggests greater complexity in evolution and adaptation. The Nature research identified mutations related to APOBEC3, an enzyme that is the hallmark of human-to-human transmission of the virus. In other words, the virus appears to be adapting to better transmit between people.
Already in the study from early June, researchers warned that the sustained spread of this lineage in Kamituga raised significant concerns. Because it is a mining town, people there frequently travel between Kamituga and the nearby city of Bukavu, with trips to neighbouring countries.
In addition, they warned, the sex workers who operate in Kamituga have several nationalities and often return to their countries of origin. “We are warning everyone about this,” Placide Mbala, an epidemiologist at the National Institute for Biomedical Research in the Democratic Republic of the Congo, told Science. One of the reasons that the WHO gave yesterday for declaring a health emergency is that neighboring countries to that country, such as Burundi, Rwanda and Uganda, reported cases of this mutated lineage of cladi I, when they had never previously confirmed cases of monkeypox.
Experts believe the actual number of cases is higher as a large proportion of clinically compatible cases have not been tested. “The emergence of a new mpox clade, its rapid spread in eastern Democratic Republic of the Congo and the reporting of cases in several neighbouring countries are of great concern. Coupled with outbreaks of other mpox clades in the Democratic Republic of the Congo and other countries in Africa, it is clear that a coordinated international response is needed to stop these outbreaks and save lives,” said WHO Director-General Tedros Adhanom Ghebreyesus.
The situation in Colombia and the Americas
Since the monkeypox clade II epidemic began in 2022, and as of August 2024, the National Institute of Health has confirmed 4,257 cases. Of that total, 109 have occurred during 2024 alone. The distribution of confirmed cases is concentrated in territorial entities such as Bogotá, Antioquia and Cali. Together they account for 84.8%.
According to INS, phylogenetic analyses of the Colombian Mpox genome during the 2022 outbreak confirmed the close relationship with clade II of West Africa, which is associated with fewer complications and lower mortality. Clade I, which currently affects the Democratic Republic of the Congo, has not been identified in Colombia.
Although Colombia’s characteristics differ from the situation in the African country, the country “is prepared and is taking measures to strengthen epidemiological and laboratory surveillance, in addition to raising awareness among health professionals (clinical specialists) in the early detection of cases and in the special differentiation of exanthematic diseases in Benefit Plan Administrator Entities, EAPB, in Health Service Provider Institutions, IPS, laboratories and populations at higher risk for contagion,” explained the general director of INS, Giovanny Rubiano García.
Among the preventive measures for health care workers, the INS includes reinforcing routine infection prevention practices, especially if they are in contact with probable or confirmed cases in travelers or handling samples. Physicians should suspect cases based on clinical and epidemiological criteria, paying attention to recent travel to African countries with active outbreaks or contact with animal reservoirs of the virus.
In addition, says the INS, it is essential to reinforce surveillance of diseases that cause skin rashes and recommend the permanent use of condoms in populations at higher risk during any type of sexual activity. Finally, there must be “permanent communication and prevention with populations at higher risk of being affected, which are men who report having sexual relations with other men, especially those who have recently changed partners, frequently exchanged partners or recently traveled.”
How to treat monkeypox?
According to the Pan American Health Organization (PAHO), “There are no specific treatments for monkeypox virus infection. Symptoms of monkeypox usually resolve spontaneously. Clinical care for monkeypox should be optimized to relieve symptoms, manage complications, and prevent long-term sequelae. It is important to care for the rash by allowing it to dry if possible or covering it with a moist dressing to protect the area if necessary.”
She also recommends not touching any sores in the mouth or eyes. “Mouthwashes and eye drops can be used as long as products containing cortisone are avoided.”
An antiviral drug that was developed to treat smallpox (tecovirimat, marketed as TPOXX) was approved for the treatment of monkeypox in January 2022.
Likewise, there is one fundamental issue that PAHO reminds us of: “It is important to distinguish monkeypox from chickenpox, measles, bacterial skin infections, scabies, herpes, syphilis, other sexually transmitted infections, and allergies associated with medications. A person with monkeypox may also simultaneously have another sexually transmitted infection.”
According to the latest epidemiological alert from PAHO/WHO, “mass vaccination against monkeypox in the population is neither required nor recommended; every effort should be made to control the spread of monkeypox from person to person through early detection and diagnosis of cases, isolation and contact tracing (…) Vaccination should only be offered to close contacts of a confirmed case of monkeypox.”
However, as noted in April by a group of experts from the Americas in the final declaration of the “Consultative Meeting on Integrating and Strengthening Responses to MPOX, Syphilis and Other STIs on the Road to Elimination,” it is key to consider vaccination in risk groups, a measure that, however, is subject to the availability of vaccines.
