Middle East respiratory syndrome-related coronavirus (MERS-CoV)

The Middle East respiratory syndrome-related coronavirus (MERS-CoV) is a potentially deadly virus that was first detected in Saudi Arabia in 2012. The virus is a type of coronavirus, a specific biological agent named for its distinctive crown-like shape. MERS-CoV was transmitted to humans from dromedary camels, although scientists believe that the virus initially originated in bats. The virus causes a disease known as Middle East respiratory syndrome (MERS), which has proven to be fatal in about one-third of all cases. Despite its high fatality rate, MERS-CoV does not spread easily among humans. Since its initial discovery, the virus has been identified in twenty-seven countries and is responsible for more than 850 deaths.

Background

A virus is a microscopic biological agent that must infect a living host to survive and reproduce. Viruses are made up of genetic material such as DNA or RNA and typically encased in a protective coating of proteins. They reproduce by coming into contact with a host cell and injecting their genetic material into the cell’s center, or nucleus. This material then takes over the cell’s functions and instructs it to make copies of the virus. The process destroys the cell while the newly replicated viruses seek out more host cells to infect.

Scientists classify viruses in several ways based on their shape, behavior, and other characteristics. A coronavirus is a virus made up of a single strand of RNA surrounded by a spiky ring of proteins. This crown-like shape gives the virus its name, as corona in Latin means “crown.” Most viruses are species specific, meaning they are confined to a specific host species. Coronaviruses are known as zoonotic viruses, which means they can “jump” from animals to humans. As of 2021, scientists have identified seven types of coronaviruses that can affect humans. Four of those viruses are minor and cause symptoms similar to the common cold. More serious types of coronavirus include SARS-associated coronavirus (SARS-CoV), which killed more than 770 people during an outbreak in 2003. More recently, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, or COVID-19) caused a worldwide pandemic in 2020 that killed more than two million people by early 2021.

Overview

Middle East respiratory syndrome-related coronavirus (MERS-CoV) was first identified in a patient in Saudi Arabia in September 2012. Medical investigators later traced the origins of the virus in humans back to its first known case in Jordan in April 2012. Further research indicated that the virus was passed on to humans from dromedary camels, although the exact mechanism of that transmission remains unknown as of 2021. Scientists believe that the virus originated in bats and was later passed on to the camels sometime in the past.

In May 2013, the International Committee on Taxonomy of Viruses (ICTV) officially named the newly discovered virus Middle East respiratory syndrome-related coronavirus, after the disease caused by the virus—Middle East respiratory syndrome. At that time, the virus had been detected in forty-four people, with twenty-two of those cases resulting in death. The World Health Organization (WHO) declared the virus a significant public health risk and recommended enhanced surveillance of the situation.

The main symptoms of MERS include fever, cough, and shortness of breath, although in many cases these are accompanied by more severe conditions such as pneumonia and kidney failure. Patients have also experienced digestive problems such as abdominal pain, diarrhea, nausea, and vomiting. Since 2012, MERS has exhibited a fatality rate of 35 percent, although scientists caution that number may be artificially high as some people with the disease show mild to no symptoms and may not have reported their illness. Most of those who have died from the virus had weakened immune systems from pre-existing medical conditions such as diabetes, cancer, or chronic lung, heart, or kidney disease. Symptoms usually occur five or six days after exposure, but in some cases they may appear in as few as two or as many as fourteen days.

As with most viruses, there is no cure for MERS-CoV. Treatment options are relegated to relieving symptoms and involve rest, drinking fluids, and taking pain relievers. In more severe cases, oxygen therapy may be recommended. As of 2021, researchers have yet to have success in developing a vaccine for MERS-CoV, although their efforts are continuing.

While some infected individuals contacted MERS-CoV from camels, the majority of human transmission has been from person to person. However, because transmission of the virus does not occur easily, person-to-person spread has only been reported in people who have had close contact with one another. This spread has mainly been limited to family members and workers in healthcare settings. As of 2020, scientists have not observed any community spread of the disease.

Since 2012, more than 2,500 cases of MERS-CoV with 858 known deaths have been reported in twenty-seven countries worldwide. These cases all have a direct connection to the Arabian Peninsula, with the majority of those infected either living there or having recently traveled to the region. A small number of those infected came into close contact with a returning traveler. About 80 percent of MERS-CoV cases have been reported in Saudi Arabia, with other Middle Eastern nations also reporting significant cases. The largest outbreak of the virus outside the Middle East occurred in South Korea in 2015. In that instance, the source of the outbreak was a traveler who had just returned from the Arabian Peninsula. Reports of MERS-CoV have also been observed in France, the United Kingdom, and the United States. However, in each case, the spread of the disease has been limited and connected to foreign travel.

According to the European Centre for Disease Prevention and Control, sixty-five MERS-CoV cases were reported from January 1, 2020, to January 12, 2021. The vast majority—sixty-one—occurred in Saudi Arabia, with three reported in the United Arab Emirates and one in Qatar. Of those cases, twenty in Saudi Arabia proved fatal.

Bibliography

“About MERS.” Centers for Disease Control and Prevention, 2 Aug. 2019, www.cdc.gov/coronavirus/mers/about/index.html. Accessed 2 Feb. 2021.

“Human Coronavirus Types.” Centers for Disease Control and Prevention, 15 Feb. 2020, www.cdc.gov/coronavirus/types.html. Accessed 2 Feb. 2021.

Li, Fang, and Lanying Du, eds. MERS-CoV. Multidisciplinary Digital Publishing Institute, 2019.

“MERS-CoV Worldwide Overview.” European Centre for Disease Prevention and Control, 12 Jan. 2021, www.ecdc.europa.eu/en/middle-east-respiratory-syndrome-coronavirus-mers-cov-situation-update. Accessed 2 Feb. 2021.

“Middle East Respiratory Syndrome Coronavirus (MERS-CoV).” Sino Biological, 2021, www.sinobiological.com/research/virus/mers-cov-overview. Accessed 2 Feb. 2021.

“Middle East Respiratory Syndrome Coronavirus (MERS-CoV).” World Health Organization, 11 Mar. 2019, www.who.int/news-room/fact-sheets/detail/middle-east-respiratory-syndrome-coronavirus-(mers-cov). Accessed 2 Feb. 2021.

“Naming of the Novel Coronavirus.” World Health Organization, 28 May 2013, www.who.int/csr/disease/coronavirus‗infections/NamingCoV‗28May13.pdf. Accessed 2 Feb. 2021.

Tosh, Pritish K. “What Is MERS-CoV, and What Should I Do?” Mayo Clinic, 20 Nov. 2020, www.mayoclinic.org/diseases-conditions/sars/expert-answers/what-is-mers-cov/faq-20094747. Accessed 2 Feb. 2021.