Middle East respiratory syndrome coronavirus (MERS-CoV), previously known as novel coronavirus (nCoV), is a viral respiratory illness, which was first reported in Saudi Arabia, in 2012. The source of MERS is currently unknown, though it is likely to have originated from an animal.
The MERS virus is currently spreading in South Korea. This, in combination with the fact that coronaviruses can often mutate, has caused increased fear that MERS could become a pandemic.
MERS-CoV is dissimilar to other coronaviruses; there is currently no vaccine.
Most confirmed cases of MERS-CoV have displayed symptoms of severe acute respiratory illness. Approximately 36% of patients reported to have MERS have died.
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You will also see introductions at the end of some sections to any recent developments that have been covered by MNT's news stories. Also look out for links to information about related conditions.
Fast facts on MERS
Here are some key points about MERS-CoV. More detail and supporting information is in the main article.
- MERS-CoV was first reported in Saudi Arabia in 2012.
- MERS-CoV belongs to the coronavirus family.
- All cases have been linked to countries in and neighboring the Arabian Peninsula.
- Cases of MERS-CoV reported in other countries were travel-related and first developed in the Middle East.
- Mammals are thought to play a role in the transmission of the virus, with bats and camels likely vectors for the disease.
- In addition to humans, strains of MERS-CoV have been identified in camels in Qatar, Egypt and Saudi Arabia, and in a bat in Saudi Arabia.
- Doctors describe MERS-CoV as a flu-like illness with signs and symptoms of pneumonia.
- Sufferers of MERS-CoV will generally develop severe acute respiratory illness. Some people have reported mild respiratory illness with others showing no symptoms.
- There are no specific treatments for patients who become ill with MERS-CoV infection.
- Out of the confirmed cases of MERS-CoV, around 36% have been fatal.
MERS Outbreak updates
August 10, 2015
Saudi Arabia's health ministry (MOH) has reported 10 new MERS-CoV cases, as well as 1 death in Riyadh occurring August 7-10, 2015. One health care worker is included in these latest cases, with seven patients in stable condition, three in critical condition, and one in home isolation.
August 6, 2015
The National IHR Focal Point for the Kingdom of Saudi Arabia informed the World Health Organization of two additional cases of Middle East respiratory syndrome coronavirus (MERS-CoV) infection on July 29, 2015. The two patients are a 67-year-old male from Riyadh city (currently in critical condition in ICU), and a 44-year-old female from Alkharj city (currently in stable condition).
June 28, 2015
The South Korea Prime Minister has announced a "de facto end" to the MERS-CoV outbreak, which has killed 36 people in the country to date. No new infection has been reported in 23 days, however, WHO have refused to confirm this. According to WHO, a 28-day incubation period is required - the last infection in South Korea was recorded on July 4, 2015.
June 24, 2015
An additional six cases of MERS-CoV were reported in Saudi Arabia in July. Since 2012, WHO have been notified of 1,374 laboratory-confirmed cases of infection with MERS-CoV to date, including at least 490 related deaths around the world.
June 5, 2015
In light of the recent outbreak of Middle East respiratory syndrome coronavirus (MERS-CoV), WHO and the Republic of Korea's Ministry of Health and Welfare will conduct a joint mission in the Republic of Korea.
This joint mission is to gain information and review the situation in the Republic of Korea including the epidemiological pattern, the characteristic of the virus and clinical features.
Based on current data and WHO's risk assessment, there is no evidence to suggest sustained human-to-human transmission in communities and no evidence of airborne transmission.
June 2, 2015The outbreak of MERS-CoV in the Republic of Korea continues to evolve. The Republic of Korea's first, or "index", case was confirmed on May 20, 2015.
To date, contact tracing has identified a total of 25 laboratory-confirmed cases, including the index case and among health care workers caring for him, patients who were being cared for at the same clinics or hospitals, and family members and visitors. Two of these confirmed cases have been fatal.
June 2, 2015
By June 2, 2015, a total of 1,179 laboratory-confirmed cases of human infection with MERS-CoV have been reported to WHO since 2012, including at least 442 deaths.
What is MERS?
MERS-CoV belongs to the coronavirus family - the same family of viruses that cause the common cold. Human coronaviruses were first classified in the mid-1960s, with the coronavirus subgroups defined as alpha, beta, gamma and delta. There are currently six coronaviruses known to affect humans, including:
MERS-CoV belongs to the coronavirus family. Human coronaviruses were first classified in the mid 1960s. MERS-CoV was first reported in 2012 in Saudi Arabia.
- Human coronavirus 229E
- Human coronavirus NL63 (HCoV-NL63, New Haven coronavirus).
- Human coronavirus OC43
- Human coronavirus HKU1
- Middle East respiratory syndrome coronavirus (MERS-CoV).
Coronaviruses typically infect one species type or those that are closely related. However, SARS-CoV infects both humans and animals including monkeys, Himalayan palm civets, raccoon dogs, cats, dogs, and rodents. MERS-CoV has so far been seen to infect humans, camels and bats.
The common cold is a virally related syndrome. It is connected to over 100 separate viruses, including human coronavirus.
MERS-CoV is a species in lineage C of the genus beta coronavirus, which presently includes tylonycteris bat coronavirus HKU4 and pipistrellus bat coronavirus HKU5.
MERS-CoV is a species in lineage C of the genus beta coronavirus, which presently includes tylonycteris bat coronavirus HKU4 and pipistrellus bat coronavirus HKU5. Although it features in the same subgroup, MERS-CoV is different from the coronavirus that caused the 2003 outbreak of severe acute respiratory syndrome (SARS). However, MERS-CoV and the virus that causes SARS are both similar to coronaviruses found in bats.
MERS-CoV appears most closely to resemble the not-yet-classified viruses from insectivorous European and African bats in the Vespertilionidae and Nycteridae families.
Since April, 2012, 26 countries have reported cases of MERS, with all known cases linked to countries in or neighboring the Arabian Peninsula.
Cases of MERS-CoV reported in other countries were travel-related and first developed in the Middle East. Countries that have declared cases to date include:
- Saudi Arabia
- United Arab Emirates (UAE)
- The West Bank
Cases of MERS-CoV reported in other countries were travel-related and first developed in the Middle East. Countries that have declared cases are:
- Saudi Arabia (KSA)
- United Arab Emirates (UAE)
- United Kingdom.
- Republic of Korea
Recent developments on MERS-CoV from MNT news
There are two main questions that have been raised following the South Korea outbreak: how did the virus manage to affect so many people in a country far away from the geographic region where the virus is most prevalent? And could a similar outbreak occur in other countries with sophisticated health care systems?
What causes MERS?
MERS-CoV is thought to be a zoonotic virus that can lead to secondary infections in humans. It appears that exposure to camels or camel-products is the main source of human infection, although the virus has also been seen in bats. Human-to-human transmission has also been observed, primarily in health care settings rather than in the community.
It is thought mammals play a role in the transmission of the virus - bats and camels remaining a high contender.
In addition to humans, strains of MERS-CoV have been identified in:
- Camels in Qatar, Egypt and Saudi Arabia
- A bat in Saudi Arabia.
MERS-CoV antibodies were found in camels across Africa and the Middle East, indicating that they had previously been infected with MERS-CoV or a closely related virus.
Researchers from three centers in the United States and two in Saudi Arabia conducted complete genetic sequences for MERS-CoV isolates generated from five camels; the results verified that these were identical to published sequences of isolates from human.
Goats, cows, sheep, water buffalo, swine and wild birds have been tested for antibodies to MERS-CoV; none have yet been detected.
The findings above support the hypothesis that camels are a probable source of infection transfer to humans, while bats may be the ultimate reservoir of the virus. Close contact between a person and an infected camel appears to be necessary for the transmission of MERS-CoV, and it has been suggested that the virus could infect humans through air, and through consumption of camel milk or meat.
Experts have commented that although the respiratory route of transmission is the most likely, research suggests that MERS-CoV can survive in raw camel milk marginally longer than milk of other species. This has prompted calls for further investigation of the potential for foodborne transmission of the virus.
Recent developments on MERS-CoV causes from MNT news
Researchers have discovered what they believe could be the animal origin of Middle East respiratory syndrome (MERS) - after examining a bat in Saudi Arabia near where the first person was infected with the mystery virus.
Previous research has suggested that camels could be a carrier of the virus, passing it to humans, but a new study has confirmed for the first time that camels actually emit volumes of the virus - making them suspect number one for spreading it to humans.
Symptoms of MERS
The most common symptoms of MERS are:
- Fever 100 degrees F or higher
- Breathing difficulties
- Chest pain
- Body aches
- Sore throat
- Malaise - a general feeling of being unwell
- Runny nose
- Renal (kidney) failure
Doctors describe MERS as a flu-like illness with signs and symptoms of pneumonia. Early reports described symptoms as similar to those found in cases of SARS (severe acute respiratory syndrome). However, unlike MERS-CoV, SARS infections did not cause renal failure.
Sufferers of MERS will generally develop severe acute respiratory illness, although some people have reported mild respiratory illness and others remain asymptomatic.
On the next page we look at who is most at risk, the difference between MERS-CoV And SARS and the options available for prevention and treatment of MERS.