Southeast Asia Is Not the Only Source of Seasonal Flu

It has always been assumed that most of the flu epidemics have their origins in the Eastern and Southeastern parts of Asia and that the flue spreads from Asia to all other parts of the world. In contrast to this assumption, it has come to light that the Asian regions are not the only areas where the virus of influenza originates. The research was conducted by scientists from Duke – NUS Graduate Medical School, located in Singapore. The team of researchers involved people from different countries. The study showed that the virus could originate in any part of the world and in any major urban city.

Gavin Smith, lead researcher and Associate Professor at Duke – NUS Program in emerging Infectious Diseases said that the urban networks that were studied were not necessarily the only centers where these viruses can originate. Further, cities that are connected by airways are can act as the vehicle for these viruses to spread across the globe.

For the study, researchers considered Influenza A virus owing to the fact that the other two types, influenza C and influenza B were not as common as influenza A. This disease is also a very common disease and one that causes up to 500,000 deaths every year all over the world. Out of these, around 49,000 people die only in the United States. RNA samples of Influenza A virus were acquired between the years 2003 and 2006 from various parts of the world such as Japan, Europe, New York, Australia, Southeast Asia, Hong Kong and New Zealand. It was found that in samples obtained from the Asian countries, the virus had not undergone major genetic mutation when compared to samples from other parts of the world which were found to be largely diverse. There was also a profound change in the genetic diversity of virus from temperate and tropical zones.

Migration of virus was measured in terms of space and time. It was found that the genetic variations in virus that moved from south ease Asia to Hong Kong were persistent. Interestingly, it was found that the samples that they analyzed from both tropical and temperate zones were not the cause for new strains of flu virus in any year.

Virus circulates and this fact has to be kept in mind when providing vaccinations against influenza. Future studies will be based on places that have not been analyzed in the present study. In a lot of such areas, there is a serious dearth of availability of virus information.