MERS Vaccines

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Last reviewed
April 20, 2021

Middle East Respiratory Syndrome (MERS) Vaccines

The emergence of the betacoronavirus causes Middle East Respiratory Syndrome Coronavirus (MERS-CoV), a viral, often fatal, respiratory illness in humans. MERS is a zoonotic coronavirus, and the source of the virus remains unknown, says the U.S. CDC.

MERS-CoV was first reported in the Kingdom of Saudi Arabia in 2012. Human-to-human transmission is amplified among household contacts and in healthcare settings, stated the ECDC during September 2020. Scientific evidence suggests that people are infected through direct or indirect contact with infected dromedary camels.

A MERS-CoV infection can result in a high mortality rate, says the World Health Organization (WHO). From 2012 until March 11, 2021, the WHO reported a total of 2,574 MERS-CoV cases and 886 associated fatalities.

As of April 15, 2021, the U.S. CDC had not approved a MERS-CoV prevention vaccine.

MERS-COV Vaccine Candidates

  • VTP-500 (ChAdOx1) MERS-CoV is a vaccine candidate from the University of Oxford that consists of the replication-deficient simian adenovirus vector ChAdOx1, containing the MERS Spike protein antigen. The VTP-500 vaccine is administered alone both as a single administration and with a homologous prime-booster.
  • INO-4700 MERS-CoV is a DNA plasmid vaccine that expresses the MERS CoV spike (S) glycoprotein. INOVIO’s Phase 1 study of its MERS-CoV vaccine demonstrated it was well tolerated and induced high levels of antibody responses in roughly 95% of study participants. Durable antibody and T cell immune responses to INO-4700 were also maintained through 60 weeks following dosing.
  • MVA MERS (Modified Vaccinia virus Ankara) is a vaccine candidate that contains the full-length spike gene of MERS-CoV. Vaccination with MVA-MERS-S had a favorable safety profile without serious or severe adverse events. Homologous prime-boost immunization induced humoral and cell-mediated responses against MERS-CoV. A dose–effect relationship was demonstrated for reactogenicity but not for vaccine-induced immune responses.

MERS-CoV Vaccine Research News

April 14, 2021 - A large team of researchers in the Kingdom of Saudi Arabia studied the antibody responses in 48 human MERS-CoV infection survivors who had variable disease severity in Saudi Arabia. MERS-CoV–specific neutralizing antibodies were detected for 6 years postinfection. Choe et al. showed that patients who had severe disease had robust MERS-CoV neutralizing antibody titers for 1 year, and patients who had mild disease had waning antibody response over time (5). We assessed antibody responses in 48 MERS survivors who had variable disease severity and duration <6 years postinfection.

April 9, 2021 - Since the previous ECDC update published on March 5, 2021, and as of April 6, 2021, three MERS-CoV cases, including one death, have been reported by Saudi Arabia (2) and the United Arab Emirates (1).

March 17, 2021 - The WHO announced the United Arab Emirates (UAE) reported a MERS-CoV infection in a 39-year-old man who owns a camel farm. The WHO stated: 'MERS-CoV has demonstrated limited ability to transmit between humans. So far, the observed non-sustained human-to-human transmission has occurred mainly in health care settings. And the WHO does not advise special screening at points of entry concerning this event nor does it currently recommend applying any travel or trade restrictions.' The first MERS-CoV case in the UAE was reported in July 2013. Since then, 92 cases of MERS-CoV (including the current case) and 12 associated deaths have been reported in the UAE. 

March 13, 2021 - From March 14, 2020, to October 19, 2020, the Travel Medicine and Infectious Disease study reported a total of 67 SARS-CoV-2 ICU admitted patients who underwent simultaneous SARS-CoV-2 and MERS-CoV testing. Of those patients, 8 (12%) tested positive for both SARS-CoV-2 and MERS-CoV. This case series is an important addition to the medical knowledge as it showed the interaction of the coinfection of SARS-CoV-2 and MERS-CoV, said these researchers.

March 11, 2021 - The Kingdom of Saudi Arabia's Ministry of Health reported two MERS-CoV cases involving people from Riyadh.

March 5, 2021 - The European CDC published the geographical distribution of confirmed MERS-CoV cases by country of infection and year.

February 16, 2021 - The Kingdom of Saudi Arabia's Ministry of Health reported a new MERS-CoV case in the nation's capital city of Riyadh.

February 1, 2021 - The WHO reported between June through December 31, 2020, the National IHR Focal Point of Saudi Arabia reported four additional cases of MERS-CoV with one associated death. The cases were reported from Riyadh (two cases), Taif (one case), and Al-Ahsaa (one case) Regions.

January 21, 2021 - VBI expects to initiate the first Phase 1/2 clinical study of VBI-2902 in Canada in Q1 2021. VBI-2901 is a trivalent pan-coronavirus vaccine candidate expressing the SARS-CoV-2 (COVID-19), SARS-CoV (SARS), and MERS-CoV (MERS) spike proteins. To support the Phase 1/2 studies, VBI was awarded up to CAD$56 million by the Strategic Innovation Fund of the Government of Canada, to be paid as retrospective reimbursement for eligible expenses.

January 11, 2021 - A non-peer-reviewed study, 'Immunogenicity and efficacy of the COVID-19 candidate vector vaccine MVA SARS 2 S in preclinical vaccination', used their earlier experience with the Middle East respiratory syndrome coronavirus; they engineered the MVA to express the full-length SARS-CoV-2 spike protein stably when serially amplified.

MERS 2020 News

Find additional news and MERS information on this page.

NOTE: This page's content is sourced from the CDC, WHO,, and the Precision Vax network of websites. This information was last fact-checked by healthcare providers, such as Dr. Robert Carlson.