23 / 2020
Despite the availability of safe and effective vaccines, measles outbreaks still occur time and again due to insufficient vaccination rates. This also applies to Germany and can concur with serious, and in rare cases fatal disease courses. Researches of the Paul-Ehrlich-Institut have found out in the animal model that the C-protein of a virus, which is very closely related to the measles virus, is of key significance for the effectiveness of the infection and the severity of the disease course. These findings may be of use for preventing serious courses of measles infections. The Journal of Virology reports on the results in its online version of 25 November 2020.
In line with the aim of the World Health Organisation (WHO), measles should have been eradicated by 2020. Such an eradication is possible, since safe and effective vaccines against measles have been available for decades. This aim has also been pursued in the German "National Action Plan 2015 – 2020 for the Elimination of Measles and Rubella in Germany". Neither of the aims have been accomplished. Thus, in November 2020, the WHO reported that the number of deaths caused by measles increased by 50 percent world-wide between 2016 und 2019. In 2019, 514 measles cases in Germany were reported to the Robert Koch-Institut (RKI).
The exact processes and actors involved in the infection with measles virus are still not fully understood. As part of the basic research serving as pre-regulatory research at the Paul-Ehrlich-Institut, an animal model was developed to study measles infections. The latter served to find approaches for a possible viral therapy of measles virus infection. Ferrets were used for this purpose, which react highly sensitively to an infection with a virus very closely related to measles virus: canine distemper virus (CDV). Like measles virus, CDV belongs to the family of morbilliviruses.
Now, researchers in the team of Dr Christian Pfaller, head of the research group "Pathogenesis of Respiratory Viruses, Animal Models" of Division Veterinary Medicine at the Paul-Ehrlich-Institut have established that the C-protein of the morbillivirus CDV is essential for the strength of the infection (virulence) and the severity of the disease course (pathogenicity). They were able to show that viruses which are unable to express C-protein trigger a greatly weakened disease in ferrets, from which all animals recover. If the viruses express C-protein, the animals die of the infectious disease. Besides, the researchers were able to prove that if C-protein was missing, enhanced innate immune responses were triggered . The researchers presume that this is the reason for the clearly weaker course of the disease.
These findings may offer new approaches to the therapeutic treatment of morbillivirus diseases such as measles which aim at inhibiting the function of the C-protein, thus weakening the disease.
Updated: 27.11.2020
