Middle East Respiratory Syndrome (MERS) is a viral disease of the lungs that was first reported in Saudi Arabia in 2012 and has now spread to several other countries, including South Korea and the United States. Genetic material isolated from an individual that died of MERS was identical to genetic material found in one of his own camels. The infected camel possibly infected the owner and is responsible for the death of the man.
People infected with the virus initially report mild symptoms of a cold, chills, body aches, sore throat, fever, difficulty in breathing, and a cough. Some individuals report gastrointestinal issues such as diarrhea, nausea, and vomiting. When symptoms become severe, death may follow failure of the lungs and kidneys.
Most of individuals that have succumbed to infection with MERS suffered with other medical conditions, such as diabetes, cancer, chronic lung conditions, heart, or kidney disease.
MERS and SARS
There is limited scientific information on MERS. However, the MERS virus is in the same family of viruses as SARS, the virus that causes severe acute respiratory syndrome. Infection with this virus results in severe breathing difficulties which too frequently results in death. (Both the traveling businessman and his World Health Organization physician, Dr. Carlo Urbani who identified the infection as a new disease in the business person, died of the virus.)
Although there are similarities in symptoms, two major differences between MERS and SARS are: a) MERS progresses to lung failure more rapidly than SARS and b) MERS affects older individuals more than it does younger people. [The high numbers of fatalities from MERS may be related to the older age of infected persons and the fact that individuals with other conditions are more susceptible to respiratory failure].
Since so little is understood about the disease, people with diabetes, lung, kidney, and immune disorders should take precautions if they are exposed to infected individuals.
The Immune System and Infections
The only part of the body that protects us from infection is our immune system. The role of the immune system is to recognize threats from pathogens, stop, and then up regulate inflammatory responses to destroy the pathogens before they can multiply.
When the immune system is recognizes invasion by pathogens, immune cells are triggered to produce antibodies and other immune factors, such as cytokines. Cytokines are proteins that help recruit immune cells into an area to help fight the battle, and orchestrate the protective immune responses.In SARS, an over-response of the immune system, a “cytokine storm” occurs that too often results in the deaths of infected persons. It is likely that infection with MERS triggers the production of high levels of cytokines, resulting in excessive inflammation and death.
Summary:
People with unbalanced immune systems are at higher risk of having severe symptoms when infected with pathogens. It is essential that the immune system always be in balance, in homeostasis for optimal protection from disease.
The inflammatory response to infection has to be a controlled, limited response. There must be enough of an immune response to defend the body against disease, but not so great an inflammatory response that the body is harmed.
www.cdc.gov/coronavirus/mers/
www.nejm.org/doi/full/10.1056/NEJMoa1401505
www.nlm.nih.gov/medlineplus/ency/article/007192
www.cdc.gov/coronavirus/mers/
www.nejm.org/doi/full/10.1056/NEJMoa1401505
