Measles virus: Improving natural oncolytic properties by genetic engineering

Measles is a highly contagious disease with a characteristic erythematous, nonpruritic, maculopapular rash that is preceded by an unspecific prodromal illness of malaise, cough, coryza, and fever [1,2]. Although an effective live vaccine has been available for more than 30years, measles is still a significant cause of morbidity and mortality in countries with poor or no vaccination coverage. Thirty to forty million cases of measles, resulting in 777,000 deaths, have been estimated for the year 2000 [3]. Mortality is associated with extreme ages, underlying illness, low socioeconomic status, lack of access to medical care, and malnutrition. Fatalities can be caused by secondary infections such as bacterial pneumonia, which are facilitated by an immunosuppression typical for measles. About one in 1000 children develops postinfectious encephalitis that is fatal in about 10% of the patients and frequently leads to sequelae in the surviving patients. An extremely rare (1 in 105 infections) fatal complication of measles, subacute sclerosing panencephalitis, can occur several years after wildtype measles virus (MV) infection and is caused by a persisting brain infection with defective virus mutants [4].