Monkey Pox: An Enigma
Year: 2024
Type: article
Abstract: Monkey pox, renamed mpox, was declared by the WHO as a Public Health Emergency of International Concern (PHEIC) on August 14, 2024.[1] The declaration was triggered by a surge of cases of mpox in Congo and some neighboring countries. The Congo strain of the mpox virus called Clade 1b is thought to be more aggressive than the Clade 2 found in West Africa. This has to be taken in proper context. Reports that the current outbreak is mostly affecting children should be considered against the background of a country which is in the category of the least developed countries with a Human Development rank of 179 out of 191 countries. The country has been facing decades of civil war and instability. Around 600,000 refugees from this country are living in neighboring countries. Two million children face starvation, and women and children resort to hunting rodents, the reservoir of the virus, for food.[2] In the present outbreak in Congo, as on September 2024, 21,000 cases due to Clade 1 with 700 deaths have been reported in the Democratic Republic of Congo (DRC), giving an infection fatality rate of 3.33%.[3] In Congo, children comprise 70% of the cases and 85% of the deaths. Travel-associated cases of mpox due to Clade 1b have occurred in Sweden,[4] Thailand,[5] and India.[6] There have been no deaths outside Africa. The data do not support media reports of “deadly mpox.” Obviously, the children of DRC and poor African nations would be more exposed to the virus, and due to underlying malnutrition bordering on starvation, the disease can be more serious in them. Extrapolating the higher fatality particularly among children in DRC to other parts of the world with better living conditions with no likelihood of exposure to infected rodents would be inappropriate. The so called “deadlier” clade which is found in DRC may be not as deadly in other parts of the world with better living conditions. The name monkey pox itself is a misnomer. Monkeys and humans are accidental victims of monkey pox. The name has its origins due to detection of the virus from laboratory monkeys in Copenhagen, Denmark, around 1958 during research on polio virus.[7] It is enigmatic how the monkeys imported from Singapore carried the virus since in nature monkeys rarely carry the virus. Second, the research in the laboratory in Denmark was on polio virus, which has no relation with the mpox virus by any stretch of imagination. In nature, the virus is found more frequently among small animals like squirrels and other rodents. The virus belongs to the same family as smallpox virus. The eruptions have some resemblance to smallpox; however, mpox is much milder and self-limiting with the case fatality rate varying between 0 and 10% in the African continent. Outside Africa, it is near 0, perhaps due to better nutrition and access to health care. The incubation period of mpox is around 2 weeks. There is fever, muscle pain, swollen glands, and rashes, which have to be differentiated from chickenpox and other cases of fever with rashes. Human-to-human transmission is by intimate contact. Respiratory transmission is possible but not very efficient. The course of the illness is 2–4 weeks. The rashes heal without leaving any permanent scars. Nothing was heard about mpox after its initial discovery in the laboratory at Copenhagen. Decades later, mpox cases were detected in Africa in last phases of smallpox eradication during house-to-house search for pox cases.[8] The cases of mpox were scattered in Congo and Western Africa. Serology and virology in the 1980s in Africa found antibodies in very few monkeys. More frequently, antibodies were found in Gambian rats and elephant shrews. Most of the human cases, around 75%, were among poor children who lived close to animals and handled their carcasses. Among household contacts, the secondary attack rate was less than 10%, which rules out any pandemic potential. In 2003, mpox infection of humans was identified in USA.[9] This was traced to prairie dogs (small rodents) that were infected from African small mammals imported as exotic pets. Gambian rat, rope squirrel, and dormouse from the African shipment of exotic species originating in Ghana were also implicated. The biggest ever outbreak of monkey pox outside the African continent began in 2022.[10] By the end of this outbreak, there were 99,518 cases and 207 deaths from 122 countries with a case fatality rate (CFR) of 0.2%. India reported 30 cases with no deaths. On May 11, 2023, the WHO declared that mpox is no longer a PHEIC. Data from the European continent during the 2022–23 outbreaks give useful insights as well as throw up some mysteries. The majority of cases, 42%, were aged between 31 and 40 years, and interestingly, 99.5% were males. Only around 10% needed hospitalization, and only 3 (0.04%) needed ICU admissions. Interestingly, 43% of those affected were HIV-positive, and around half had history of other sexually transmitted infections in the past. Only 0.33% of the cases were health care workers. In UK, which had more detailed surveillance, 97% of the cases were homosexual or bisexual men. Of these, 54% had history of other sexually transmitted infections, and 31.8% had 10 or more sexual partners in the last 3 months. What is baffling is how the outbreak in Europe and USA in 2022–23 erupted almost simultaneously in most countries. A communicable disease spreads from person to person, then from community to community, and so on, finally crossing international boundaries in chronological pattern. Mpox, which is more common in children in its native Africa, is showing a different epidemiology outside this continent. The surveillance data from the West suggest that it is behaving more like a sexually transmitted disease like HIV and other sexually transmitted infections. Fortunately, there is very low fatality. Perhaps, intimate handling of small animals and carcasses by undernourished African children makes them more vulnerable to both infection and a fatal outcome. These epidemiological insights should guide preventive measures. Promotion of condom use and safe sex, avoidance of multiple sexual partners, and screening of blood donors are all practices which we have refined over the years in our fight against AIDS. These should suffice to control the far less virulent mpox as well. In Africa and the DRC, improvement of living standards, improved nutrition, and better access to quality health services should control the infection in the long run. The WHO position on mpox vaccine is as follows:[11] health workers at risk of exposure men who have sex with men people with multiple sex partners sex workers. The vaccine is not recommended for the general population. A self-limiting disease with almost zero mortality in the healthy with access to health care as the European data indicate and low pandemic potential, should not be cause for panic. Author contribution AB was responsible for all the concept, drafting, revision and approval of the manuscript. Data availability statement Not applicable.
Author: Amitav Banerjee
Language: English
Subfield: Virology
Field: Immunology and Microbiology
Domain: Life Sciences
Open Access status: diamond
OpenAlex ID: W4407834879