[Short Communication] Measles: 1963-2023, Immunology of a Morbillivirus

Abstract

Measles is a virus, abbreviated to MeV, that has long been known to be causal in infant disease and affect infant mortality, remaining a public health issue of priority. The causal virion is defined biologically within the Family _Paraxmyxoviridae_, Genus _Morbillivirus_ and Species _MeaslesMorbillivirus. _Similar to other viral infections, MeV is an airborne infection with the virion particle composed of a negative (-ve) sense single-stranded (ss) ribonucleic acid (RNA) genome code, around 15-16kb in size, encoding for eight predominant proteins. The first isolation of MeV occurred in 1954, known as the “Edmonston strain”. A team at Boston Children’s Hospital comprised of John Franklin Enders and others who isolated MeV from a 13-year-old serum sample. Alongside Samuel Katz and notably Maurice Hilleman, this led to the development of the first live attenuated vaccine, when in 1971, the first trivalent mumps, measles and rubella (MMR) vaccine was licensed for use in immunisation programmes in the United States of America (USA). Shortly after, in 1980, the eradication of Smallpox was confirmed by the World Health Organisation (WHO), which had been the predominant debilitating pathogen of the 20th century. Measles was then considered to be the cause of 2.6 million deaths each year. Around 1986, the MeV haemagglutinin (H) protein was crystallised _in vitro_. The introduction of MMR immunisation previously and after reduced mortality to around 110,000 annually. The rates of MeV disease since 2017 have been rising of a pathogen that is largely preventable through immunisation programs that evoke immune system responses. Smallpox (VARV) and the Rinderpest virus (RPV), a member of the same Morbillivirus genus as MeV, remain the only other animal pathogens eradicated. The lack of antigenic variation of the MeV is suggestive that MeV remains the third pathogen to potentially be eradicated. Here is a discussion of contextual Measles immunological characteristics to elucidate this further.