New research published in the journal Current Issues in Molecular Biology examines why measles continues to be one of the most contagious viral diseases worldwide, despite decades of vaccination efforts. The review analyzes scientific findings on the biology of the measles virus, how it affects the immune system, complications from infection, available treatments, and prevention strategies.
Measles is known for its high transmission rate. A single case can result in 12 to 18 secondary cases among people who are not immune. This number varies depending on population density and levels of immunity or vaccine coverage.
Globally, millions continue to contract measles each year. In 2024 alone, there were an estimated 11 million infections worldwide, including cases in countries where measles was previously thought to be eliminated. The persistence of outbreaks has been linked to gaps in immunity, hesitancy about vaccines, interruptions in routine immunization programs, and weak health systems.
The review explains that measles is caused by a negative-sense single-stranded RNA virus from the Paramyxoviridae family. It spreads mainly through airborne respiratory droplets and aerosols. Once inhaled, the virus attaches to specific receptors on immune and epithelial cells—SLAM/CD150 and nectin-4—which allows it to enter cells and replicate quickly.
After entering the body, the virus moves through lymphatic tissue and immune cells before spreading throughout various organs. People with measles are most contagious from four days before until four days after their rash appears due to high levels of virus in respiratory secretions.
The report notes that any decline in vaccination rates can lead rapidly to new outbreaks because of how easily measles spreads. Widespread use of vaccines had previously led to dramatic reductions in global cases; however, lapses allow for resurgence within vulnerable groups.
A key finding highlighted is how measles infection suppresses the immune system. Normally during infection, inflammatory molecules help activate defenses against viruses. However, proteins made by the measles virus interfere with these pathways—including interferon signaling—weakening antiviral responses.
This disruption leads to a loss of important immune cells such as CD4+ T cells, CD8+ T cells, and B lymphocytes—a condition called lymphopenia. The virus also destroys memory immune cells that had encountered other pathogens before infection. As a result of this “immune amnesia,” people recovering from measles may lose protection against other diseases for months or years afterward.
Recent molecular studies have shown that genes regulating antiviral responses are activated during infection as part of the body’s effort to fight off the virus; however, these defenses are often too late due to viral evasion strategies.
The ability of measles to disrupt immune memory has major public health implications since it increases vulnerability not only during illness but long after recovery.
While fever and rash are common symptoms associated with measles, serious complications can occur such as pneumonia (a leading cause of death related to measles), middle ear infections (otitis media), diarrhea, encephalitis (brain inflammation), acute disseminated encephalomyelitis (a rare neurological disorder), and subacute sclerosing panencephalitis (SSPE)—a fatal condition developing years after initial infection.
Children under five years old, adults over twenty years old, pregnant women or those with poor nutrition face higher risks for severe outcomes; vitamin A deficiency worsens disease severity according to World Health Organization recommendations.
There is no approved antiviral treatment specifically for measles at present; care focuses on hydration management and treating complications when they arise. Vitamin A supplements given twice during illness reduce morbidity and mortality among children according to WHO guidelines; further doses may be recommended if signs indicate deficiency persists later on.
Other supplements like antioxidants or vitamin D have been studied but lack conclusive evidence supporting their use against severe disease outcomes from measles infections.
Prevention remains critical: two doses of the combined MMR vaccine produce strong immunity against infection while protecting those unable medically receive vaccinations themselves if community coverage reaches about 95%. If exposure occurs within seventy-two hours among eligible individuals—or six days using immune globulin for infants/pregnant/immunocompromised patients—disease risk/severity can be reduced significantly.
Efforts such as improved public education campaigns about vaccination benefits alongside better surveillance systems are needed globally so communities close immunity gaps effectively prevent future outbreaks.
“The reviewed evidence highlights measles as a highly transmissible viral disease capable of causing profound immune suppression and serious complications,” states one section from researchers involved in compiling current knowledge on this subject.
“Beyond acute illness,” they add “measles virus infection can weaken immune memory increasing susceptibility other infections extended periods…prevention through widespread vaccination remains most effective strategy controlling.”
They conclude: “High vaccination awareness strengthened surveillance systems efforts address vaccine hesitancy paramount factors preventing future outbreaks protecting vulnerable populations globally.”
