Since the advent of COVID-19, every infectious disease comes under media scanner, giving the impression that a new pandemic has arrived, and causing panic.
The same is happening today with one of the rare viral infections, monkeypox. The name monkeypox comes from the first discovery of the virus in monkeys in 1958 at a Danish laboratory.
According to the WHO, cases occur near rainforests where virus-carrying animals live. Monkeypox virus infection has been reported in several species of squirrels, poached Gambian rats, dormice, and some species of monkeys.
It is currently a rare zoonotic disease caused by the monkeypox virus (a double-stranded DNA virus of the Orthopoxviridae family) and is closely associated with the smallpox virus, which has the same clinical picture in humans.
Because of this similarity, monkeypox was not recognised as a cause of human illness until 1970, when the first case was reported in a 9-month-old baby boy. Before 2003, monkeypox was confined to the central and western parts of Africa and believed to be endemic to several species of small mammals.
The U.S.A reported an outbreak of human monkeypox in 2003, with seventy-two cases, of which 37 were laboratory confirmed without any deaths or human-to-human transmission.
The outbreak was linked to prairie dogs that had been kept with exotic animals shipped from Ghana. Presently, a multi-country outbreak of monkeypox (reported in at least 20 countries) has been on-going since early May 2022.
As of May 30, 2022, a total of 434 confirmed cases have been reported worldwide, most of which have been detected in young men. The development of this virus in different populations globally, in places where it isn’t often seen, has concerned scientists and set them scrambling for explanations.
Seeing this kind of spread is now eye-opening. But monkeypox isn’t like the SARS-CoV-2 that caused the COVID-19 pandemic; it doesn’t spread as easily, and because it’s related to smallpox, FDA-approved treatments and vaccines are already available to stop it from spreading. So, although scientists are concerned because any novel viral behaviour is worrying, they are not panicked.
Unlike SARS-CoV-2, which spreads through small airborne droplets called aerosols, monkeypox is thought to spread through close contact with body fluids such as cough and saliva. Therefore, a person infected with monkeypox is much less likely to infect close contacts than someone infected with SARS-CoV-2.
Both viruses can cause flu-like symptoms, but monkeypox causes swollen lymph nodes and ultimately fluid-filled lesions characteristic of the face, hands, and feet. Most people recover from monkeypox within a few weeks without treatment.
The clinical picture of monkeypox starts with a smallpox-like prodrome after a 10- to 14-day incubation period. Rashes, fever, chills, headaches, and muscle aches are among the clinical symptoms recorded. The rash resembles that of smallpox, but it may be less extensive. Lymphadenopathy is noticeable and may help differentiate monkeypox from smallpox. Contrary to Variola, infections might be asymptomatic or subclinical.
Humans get infected through personal contact, touching lesions, and wearing contaminated clothing. The virus can enter the body through broken skin, the eyes, nose, or mouth, and it can also be transmitted during sexual intercourse by skin-to-skin contact, which is why the majority of episodes in the United Kingdom have been found in gays and bisexual men.
Close contact, biting, scratching, and eating meat are all methods of transmission in animals. Although human-to-human transmission is suspected, studies of African outbreaks show that only 8% to 15% of unvaccinated household contacts become infected.
Although the majority of cases have been mild, the condition can be more serious in small children, pregnant women, and those with compromised immune systems. The overall case fatality rate ranges from 0% to 11%.
PCR, electron microscopy, and serology are some of the diagnostic approaches for monkeypox infection. Immunization against smallpox is beneficial in reducing monkeypox transmission, and vaccination after exposure can help to prevent or alleviate illness.
There is still no established therapy for human monkeypox, and concerns about its potential as a bioterrorism agent persist. Monkeypox infections, on the other hand, are treated with a variety of FDA-approved antiviral drugs that are used to treat smallpox.
The most commonly prescribed antivirals are Tecovirimat (600 mg orally twice daily for 14 days), Brincidofovir (two doses of 200 mg orally twice daily), and Cidofovir. Cidofovir is efficacious against monkeypox in animal models but lacks human data.
For the last two decades, two vaccines already used for smallpox, ACAM2000 (given percutaneously by multiple puncture technique in a single dose) and JYNNEOS (provided subcutaneously in two doses, 28 days apart), have been at the forefront of monkeypox virus protection.
For post-exposure prophylaxis Vaccinia immunoglobulin (antibodies) is also recommended for 14-day treatment of patients, especially those who are immunocompetent.
On May 19, researchers in Portugal uploaded the first draft genome of the monkeypox virus, but Gustavo Palacios, a virologist at Mount Sinai’s Icahn School of Medicine in New York City, emphasises that it is still a very early draft and that more work is needed before any definitive conclusions can be drawn.
So, what researchers can deduce from this preliminary genetic data is that the monkeypox virus strain detected in Portugal is connected to a viral strain prevalent primarily in West Africa. When compared to the type that circulates in Central Africa; this strain causes milder sickness and has a fatality rate of roughly 1% in poor rural people.
However, it’s unclear how much the strain causing the recent outbreaks differs from the one in West Africa, and whether the cases springing up in different countries are linked. Answers to those questions could help researchers figure out whether the unexpected increase in cases is due to a mutation that permits monkeypox to spread more easily than before, and whether each outbreak has a single source.
Monkeypox is caused by a quite large DNA virus, unlike SARS-CoV-2, a rapidly evolving RNA virus whose variants have routinely defied immunity from vaccinations and prior infection. Since DNA viruses are better at detecting and fixing mutations than RNA viruses, the monkeypox virus is unlikely to have mutated to become efficient at human-to-human transmission.
It’s also worrisome that monkeypox has been identified in people who have no obvious connection to one another, implying that the virus has been spreading quietly. Monkeypox does not normally go unnoticed when it infects a person, unlike SARS-CoV-2, which can spread without displaying symptoms.
This is due to the skin sores it creates. It would be especially concerning if monkeypox virus could spread without symptoms, as this would make the virus more difficult to trace.
When it comes to containment methods, public health officials are not invincible against monkeypox. Countries like the United States keep smallpox vaccines on hand as a precaution against bioterrorism, as well as an antiviral therapy that is thought to be highly efficient against the virus.
The medicines, however, are unlikely to be used on a big basis to combat Monkeypox. To control the spread of the virus, health-care personnel would most likely utilise a practice known as ‘ring vaccination,’ in which close contacts of persons who have been infected with monkeypox are vaccinated to cut off any transmission channels.
Based on the reports and scientific evidence the current outbreaks won’t demand any containment tactics other than ring vaccination.
Dr. Abrar Ul Haq Wani, Assistant Professor cum Junior Scientist, Department of Medicine, Guru Angad Dev Veterinary and Animal Sciences University, Ludhiana, Punjab.
Disclaimer: The views and opinions expressed in this article are the personal opinions of the author.
The facts, analysis, assumptions and perspective appearing in the article do not reflect the views of GK.