MERS Vaccines

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Last reviewed
June 29, 2022

Middle East Respiratory Syndrome (MERS) Vaccines

The emergence of the beta coronavirus causing Middle East Respiratory Syndrome Coronavirus (MERS-CoV) is zoonotic and can be very lethal, says the U.S. CDC. The source of the viral virus remains unknown.

As of June 29, 2022, the U.S. FDA had not approved a MERS-CoV prevention vaccine, but several are conducting clinical trials.

MERS-COV Vaccine Candidates - 2022

BVRS-GamVac-Combi is conducting phase 1/2 clinical studies sponsored by the Gamaleya Research Institute of Epidemiology and Microbiology, Health Ministry of the Russian Federation.

VTP-500 (ChAdOx1) MERS-CoV is a vaccine candidate from the University of Oxford that consists of the replication-deficient simian adenovirus vector ChAdOx1 MERS Spike protein antigen. The VTP-500 vaccine is administered 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. In addition, durable antibody and T cell immune responses to INO-4700 were also maintained through 60 weeks following dosing. The phase 2 study has dosed its initial participant.

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 severe adverse events. Homologous prime-boost immunization induced humoral and cell-mediated responses against MERS-CoV. In addition, a dose-effect relationship was demonstrated for reactogenicity but not for vaccine-induced immune responses.

The inactivated rabies vectored SARS-CoV-2 S1 vaccine CORAVAX is an adjuvanted with MPLA-AddaVax, a TRL4 agonist, induced high levels of neutralizing antibodies and generated a strong Th1-biased immune response. 

MERS-CoV Vaccine News For 2020 - 2022

June 28, 2022 - The UK Health Security Agency confirmed it does not advise any travel restrictions to the Kingdom of Saudi Arabia concerning MERS-CoV.

May 17, 2022 - The WHO was notified of a case of MERS-CoV from the Al Dhahira Governorate in Oman. The male case had a history of direct contact with animals, including dromedaries, sheep, and goats. No secondary cases have been reported to date. Since June 2013, a total of 25 MERS-CoV cases, including the current case, and seven deaths, have been reported to WHO from Oman.

May 12, 2022 - The WHO confirmed two laboratory-confirmed cases of MERS-CoV, including one death, were reported by the National IHR Focal Point of Qatar. These are the first cases of MERS-CoV infection reported from Qatar since February 2020. Since 2012, Qatar has reported 28 human cases of MERS-CoV, and seven deaths, including the two new reported cases. 

April 3, 2022 - Qatar's Ministry of Public Health (MOPH) reported a second MERS-CoV case. The patient had a history of travel outside the country and had direct contact with camels. Unfortunately, he started to develop symptoms before he arrived in Qatar.

March 22, 2022 - Qatar's Ministry of Public Health declared that a case of MERS had been confirmed in a male resident aged 50 years. He had direct contact with camels. All of the human contacts of the patient are free of symptoms and will be monitored for 14 days as per the national protocols.

February 24, 2022 - A non-peer-reviewed study: A single dose of the deactivated rabies virus vectored COVID-19 vaccine, CORAVAX, is highly efficacious and alleviates lung inflammation in the hamster model. In summary, CORAVAX is a promising dual antigen vaccine candidate for clinical evaluation against SARS CoV-2 and Rabies virus.

January 31, 2022 - The peer-reviewed journal frontiers in Immunology published an ORIGINAL RESEARCH article: Inactivated Rabies Virus Vectored MERS-Coronavirus Vaccine Induces Protective Immunity in Mice, Camels, and Alpacas. Collectively, the current results demonstrate that the inactivated rabies virus-vectored MERS-CoV vaccine is safe, efficacious, and able to induce robust protective immune responses, representing a promising MERS camelid vaccine candidate and warranting further efficacy study.

January 28, 2022 - The Journal of Microbiology published: the Middle East Respiratory Syndrome coronavirus vaccine development: updating clinical studies using platform technologies. Platform technologies accelerated COVID-19 vaccine development and can also be applied to developing vaccines against other emerging viral diseases.

November 4, 2021 - Vaccitech plc announced the publication in The Lancet Microbe of the first Phase 1 clinical trial conducted in the Middle East evaluating the safety and tolerability of the ChAdOx1 MERS (Middle Eastern Respiratory Syndrome) vaccine candidate.

November 3, 2021 - The Lancet published: Safety and immunogenicity of ChAdOx1 MERS vaccine candidate in healthy Middle Eastern adults (MERS002): an open-label, non-randomized, dose-escalation, phase 1b trial. Results Interpretation: The acceptable safety and immunogenicity data from this phase 1b trial of the ChAdOx1 MERS vaccine candidate in Healthy Middle Eastern adults, combined with previous safety and immunogenicity data from a trial in the U.K., support selecting the ChAdOx1 MERS vaccine for advancement into phase 2 clinical evaluation.

September 29, 2021 - The Saudi Arabian Ministry of Health announced its 13th MERS case in 2021. The new primary, active case is a 58-year-old male in Riyadh city, Riyadh. The ECDC reported this MERS patient died as of October 4, 2021.

August 26, 2021 - The Kingdom of Saudi Arabia Ministry of Health announced a 69-year-old male in Riyadh who had contact with camels was diagnosed with MERS-CoV.

August 17, 2021 - The WHO confirmed between 12 March and 31 July 2021, the National IHR Focal Point of Saudi Arabia reported four additional cases of MERS-CoV infection, including one associated death.

August 4, 2021 - INOVIO announced that the company had dosed the first subject in its Phase 2 trial designed to evaluate INO-4700, its DNA vaccine candidate for the prevention of MERS.

July 30, 2021 - The Kingdom of Saudi Arabia Ministry of Health reported a second MERS-CoV case from Riyadh in July 2021. Like the initial MERS case, the patient is age 65, was not a health worker, and isn't thought to have contracted the beta coronavirus from another sick person. This case marks Saudi Arabia's 11th MERS case of 2021.

July 21, 2021 - The Kingdom of Saudi Arabia Ministry of Health announced a 67-year-old man from Riyadh, Riyadh, who had contact with camels, including drinking camel milk, was confirmed with MERS. The man's infection is listed as Active.

July 2, 2021 - The ECDC reported from January 2021 to 29 June 2021, 10 MERS-CoV cases have been reported in Saudi Arabia (9) and the United Arab Emirates (1), including five deaths. In Saudi Arabia, all were primary cases, of whom six reported contact with camels. These nine cases were reported in Riyadh (4), Makkah (3), and the Eastern Province (2).

June 8, 2021 - The Kingdom of Saudi Arabia Ministry of Health (MOH) confirmed one new MERS-CoV case, a 63-year-old man in Taif who had contact with camels.

May 7, 2021 - The ECDC reported eight MERS-CoV cases had been reported in Saudi Arabia (7) and the United Arab Emirates (1), including four deaths. In Saudi Arabia, all were primary cases, of whom four reported contact with camels. These seven cases were reported in Riyadh (4), Makkah (2), and Eastern Province (1).

May 5, 2021 - The Kingdom of Saudi Arabia's Ministry of Health reported a new MERS-CoV case, which involves a 36-year-old man who died from his infection. The man was from Hafr Al-Batin in the country's northeast. The case marks Saudi Arabia's eighth of 2021.

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 six years after postinfection. Choe et al. showed that patients with severe disease had robust MERS-CoV neutralizing antibody titers for one year. Patients with mild disease had waning antibody responses over time (5). We assessed antibody responses in 48 MERS survivors with 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 entry points 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 essential addition to the medical knowledge as it showed the interaction of the coinfection of SARS-CoV-2 and MERS-CoV, said these researchers.


It is believed that MERS may have originated in bats and transmitted to camels. So far, MERS-CoV has been identified in the Middle East, South Korea, and Africa. Multiple MERS cases of animal-to-animal transmission among camelids and camel-to-human spillover cases. Approximately 35% of reported patients with MERS-CoV have died, but this may be an overestimate of the actual mortality rate, as mild cases of MERS-CoV may be missed by existing surveillance systems.

Since the beginning of 2022, and as of 8 June 2022, three MERS-CoV cases have been reported in Qatar (2) and Oman (1), including one death. All three cases were primary cases, having reported contact with camels. 

A report issued by the WHO Meditrian Region on May 17, 2022, confirmed the total number of laboratory-confirmed MERS-CoV infection cases reported globally is 2,591, including 894 associated deaths. The majority of the reported cases have occurred in countries in the Arabian Peninsula. Outside of this region, there was one large outbreak in the Republic of Korea in May 2015, during which 186 laboratory-confirmed cases (185 in the Republic of Korea and 1 in China) and 38 deaths were reported.

The U.S. FDA recently Authorized MERS-related diagnostic tests.

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