What Are the Latest Updates on the Monkeypox Outbreak?
Confirmed in May 2022, an ongoing outbreak of monkeypox virus (MPXV) has emerged in many non-endemic countries around the world. The initial cluster of monkeypox cases was documented in the UK, following the detection of the first infection in a patient with a recent travel history from Nigeria on May 6. On 16 May, the UK Health Security Agency (UKHSA) has reported 4 new monkeypox cases with no apparent link to historically-endemic countries. Thereafter, the monkeypox virus has spread to different parts of the world and new cases were confirmed from an increasing number of countries not only in Europe, but also in the Americas, Asia, and Oceania.
Declared a public health emergency of international concern (PHEIC) by the World Health Organization (WHO), the current multi-national outbreak marks the first time that the monkeypox virus has spread widely outside the historically-endemic countries in Central and West Africa. With the world facing the challenges posed by both monkeypox and COVID-19, efforts to develop more efficient vaccines and diagnostic tests against monkeypox have also accelerated. Read along to learn more about the latest updates on monkeypox, the current state of the outbreak, the monkeypox vaccine, and different testing options for monkeypox.
What is the monkeypox virus (MPXV)?
Monkeypox is a viral zoonotic disease caused by infection with monkeypox virus (MPXV). Monkeypox virus is an enveloped double-stranded DNA virus from the Orthopoxvirus genus in the family Poxviridae. As such, the monkeypox virus (MPXV) is closely related to various viruses such as the variola virus which causes smallpox, the vaccinia virus which was used for the development of smallpox vaccine, cowpox virus, and camel pox virus. While monkeypox was named after its initial discovery in monkeys in a Danish laboratory in 1958, various animal species has since been found vulnerable against the monkeypox virus, such as rope squirrels, tree squirrels, Gambian pouched rats, and dormice.
What are the symptoms of monkeypox?
Symptoms of monkeypox typically resemble those of smallpox but are usually milder. The most common symptoms of monkeypox include fever, chills, headache, lethargy, muscle pain, joint pain, swollen lymph nodes, fatigue, and back pain, followed by a rash which appear 1 to 5 days after the symptom onset.
How does the monkeypox virus (MPXV) transmit?
The monkeypox virus (MPXV) may enter via broken skin, respiratory tract, and mucous membranes including the eyes, nose, or mouth. The disease primarily spreads through close contact with the blood, bodily fluids, and lesion material of infected people and animals, or through contact with contaminated materials. While the monkeypox virus is known to affect anyone, the majority of the cases observed in the current outbreak outside the endemic regions has been found to involve men who have sex with men (MSM) with recent history of sexual contact with new or multiple partners. Accordingly, on July 28, the World Health Organization (WHO) has recommended men who have sex with men (MSM) to limit the number of sexual partners, reconsider engaging in intercourse with new partners, and maintain contact details to enable epidemiological follow-up.
What is the current state of the monkeypox outbreak?
While the actual burden of monkeypox is likely to be underestimated due to the unexpected and vast geographical spread of the disease, as of 18 October, 73,531 confirmed cases and 30 deaths in total had been documented in over 109 countries. A recent epidemiological update by the European Centre for Disease Prevention and Control (ECDC) illustrates that the number of confirmed monkeypox cases in the EU/EAA has decreased consistently and significantly during the last few weeks. On the other hand, although Europe had initially been the primarily affected region by the monkeypox outbreak, according to Our World in Data, as of October 18, countries with the highest level of 7-day rolling average of confirmed monkeypox cases include the US, Brazil, Colombia, and Peru.
Is there a vaccine developed against the monkeypox virus (MPXV)?
Thanks to the cross-protection afforded for the immune response to orthopoxviruses, vaccines that have been originally developed for smallpox can provide significant protection against the monkeypox virus. There are currently two vaccines available for use against the monkeypox virus. According to Centre for Disease Prevention and Control (CDC), smallpox vaccines containing the vaccinia virus such as Jynneos (Imvanex) and ACAM2000 can offer approximately 85% efficacy against the monkeypox virus. Similarly, Pittman et al. (2019) has found that the antibody responses with the Jynneos (Imvanex) and ACAM2000 vaccines were comparable.
Similar to vaccines, antiviral treatments developed against smallpox have potential to be effective against monkeypox. In fact, as both agents have proven to be effective against poxviruses, antiviral treatment with cidofovir and tecovirimat has been suggested for use against monkeypox. Originally used in the treatment of smallpox, tecovirimat was recently licensed by the European Medical Association (EMA) for use against monkeypox based on human and animal studies.
Which testing options are available in the diagnosis of monkeypox?
For now, monkeypox is diagnosed in the laboratory by direct detection of viral DNA. Viral detection of monkeypox may involve the use of a nucleic acid amplification test (NAAT), such as a polymerase chain reaction (PCR) test. Apart from molecular methods based on the detection of viral DNA, rapid antigen tests and rapid antibody tests are also available to assist the diagnosis of monkeypox infections. Rapid antigen test kits, such as our RapidForTM Monkeypox Virus Antigen Test Kit checks for the monkeypox virus (MPXV) antigens and delivers highly accurate results in 15 minutes. On the other hand, rapid antibody tests, such as our RapidForTM Monkeypox Virus Antibody Test, detects antibodies against monkeypox virus to determine the immunity level following infection.
References For Text
Pittman, P. R., Hahn, M., Lee, H. S., Koca, C., Samy, N., Schmidt, D., Hornung, J., Weidenthaler, H., Heery, C. R., Meyer, T. P., Silbernagl, G., Maclennan, J., & Chaplin, P. (2019, November 14). Phase 3 Efficacy Trial of Modified Vaccinia Ankara as a Vaccine against Smallpox. New England Journal of Medicine, 381(20), 1897–1908. https://doi.org/10.1056/nejmoa1817307