Measles Victim – Vulnerable to Other Infections
It is said that around 140,000 people are affected by measles every year all over the world though millions of kids who tend to survive the disease are not out of danger. Latest research indicated that they tend to be vulnerable to other infections for over two years much longer than what the researcher anticipated. The outcome strengthen a hypothesis that measles virus weakens the immune system’s memory, indicating that the measles vaccine protects against other dangerous diseases also.
Researchers have known for long that measles constraint the immune system though they usually believe this would wear off after a few months. Nevertheless where most of the cases occur, studies in children in the developing countries have indicated that measles vaccination has reduced the overall death rate from infection for up to 5 years signifying that preventing of the disease could provide protection against other ailments. A possibility of this benefit is that the vaccine for measles spurs the immune system in producing defences against the other disorders. Rik de Swart of Erasmus MC in Rotterdam, Netherlands, together with his colleagues, revealed in 2012, that the measles virus tend to kill a huge number of memory cells, white blood cells which prevent the subsequent infection by the same pathogen.
Measles Virus Impair Immune System
According to what the scientist called immunological amnesia, the measles virus impaired the immune system’s capability to remember and quickly eradicate other microbes which has already been beaten resulting in making the person vulnerable to diseases they should not be according to Michael Mina, lead author of the new paper and medical student at Emory University School of Medicine in Atlanta. To check this explanation out a team including De Swart and Mina, postdoc at Princeton University at that time, achieved data on the numbers of measles cases and death from various other infections in the U.S.; Denmark and other part of the United Kingdom.
The researchers had statistics from before and after the introduction of measles vaccination which started in 1960s in the United Kingdom and United States and in the 1980s in Denmark. Their mathematical analysis attempted to define if there was a connection between the number of measles cases and the number of kids who had died from other disorders. If the virus tends to prevent immunity for a short time for instance, the number of deaths from other infections in a certain year could correlate to the number of measles cases during that year. However, if the virus activates a prolonged immune amnesia, the total number of deaths in a particular year could correlate to the total number of cases during that and the previous year or two.
Analysed Statistics for Whooping Cough
With the use of this approach, the researchers then calculated that children who survived the measles disease became susceptible to the other diseases for an average of 2.5 years. The team had recently reported online in Science, that the result was the same for all three countries. Mina has commented that `their results suggest that the adverse effects of measles are much more lasting’. Moreover, in order to test that the immune impairment was caused due to measles, the researchers analysed statistics for whooping cough that does not suppress the immune system.
They discovered no link between the number of whooping cough cases and mortality from the other infections conditions. Mina and his team determined that the length of vulnerable period did not make any changes in any of the three countries following the introduction of the vaccination. This result supported the idea that the measles vaccine benefits children not only because it tends to prevent them from being affected with measles but also due to the fact that it provides protection against the other disorders. Prior to the days of vaccination, this disease was responsible for around half of children deaths from other illnesses according to the team.
Possibility of Immunosuppression
Many have presumed that measles’ impact on the immune system, faded quickly and Mina states that `when a kid tends to get pneumonia 6 months later, no one would link that to measles’. Other studies of children in West Africa did not show a lasting measles shadow. Mina together with his team observed that half of the kids in these studies died from other diseases within 2 months after they had been affected by measles that would have made it tough to detect a long term effect.
Vaccine immunologist Katie Flanagan of Monash University in Melbourne, Australia, states that `there could have been a possibility of immunosuppression. However, the study `is a long way from really proving it’. For instance, researchers need to show that the kids who had measles are the ones dying from other illnesses’, she added. William Moss, an epidemiologist at the Johns Hopkins Bloomberg School of Public Health in Baltimore, Maryland comments that `it is indirect evidence’ and that the results are `highly suggestive’ that measles is contributing to this longer period of immune suppression. Should the researcher be right, he states that the benefits of measles vaccination are far greater than simply the reduction in measles death.
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