WHO Pandemic Warning Phases.Source [pdf].
What is a pandemic?
The World Health Organization (WHO) Emergency Committee declared on August 10 that we left the pandemic phase of the H1N1 virus. “The world is no longer in phase 6 of influenza pandemic alert. We are now moving into the post-pandemic period. The new H1N1 virus has largely run [...]
After more than a year of the Influenza A H1N1 episode, the virus is still being monitored all over the world, both the flu cases and genetics diversity of the virus. Following up the genetic diversity helps to understand if the vaccine is still efficient and helps identifying the possible appearance of new strains.
In Hong [...]
A year has passed since the first cases of Influenza A H1N1 in Mexico, we had over 18000 deaths confirmed by lab diagnosis and reported to WHO. Surely an underestimate of the total number of cases.
The average mortality was of 0.5% of the confirmed cases, close to the seasonal flu. The mortality values varied a [...]
Why were the older people less affected by the new flu?
The elderly, especially those older than 65 years, that is, born before 1944, constitute the part of the population less affected by H1N1. It was suggested and later confirmed by CDC that it is about the prior immunity to the virus. These people probably have [...]
In the last text, it was discussed the capacity of H5N1 of infecting a number of hosts and causing very harsh symptoms, causing deaths in over 50% of the recorded human cases. Despite this, its transmission from person to person seems to be well limited. Now we will see its characteristics that contribute to this.
Never in history of mankind have we reared as many pigs and chickens as now. The growing demand for meat, especially in developing countries like China, exerts a great pressure in the increase of the quantity of meat in commerce. Therefore, more wild birds are being caught and more domestic birds are being bred. The [...]
Although H1N1 is circulating around us at least a little bit before 1918, we passed almost 20 years free of it. In 1957, a line of influenza virus received three genes of an avian virus, among them new HA and NA, and started to be called H2N2. With these new proteins, it did not meet [...]
Birds are important in the natural history of Influenza and flu, but there is another character besides us humans. The pigs.
Our knowledge of Influenza in pig dates back to at least 1918 when it was observed that they could also catch the flu during a time when the human flu caused an uneven pandemic. In [...]
One of the most important characteristics to be considered about the Influenza, in the preparation for pandemics, is the reassortment. A mixture of genes of two or more different viruses is able to generate a new variety. Such as the new Influenza A (H1N1).
Although the mutations have an important role in the diversity of the [...]
If measles is caused by a virus and it can only be caught once in a life time, why do we catch the flu every year?
When we have the flu, in a few days the body seems to get rid of the virus. The symptoms rarely last for two weeks and, in a higher period; [...]
There are e-mails in circulation stating that some magazines had surprisingly predicted the epidemic of Influenza A (H1N1) years in advance. I immediately remembered an excellent book, The Coming Plague by Laurie Garrett, a journalist who won the Pulitzer Award for his work in epidemics.
In this book, besides discussing a number of very dangerous epidemics, [...]
In 1997, a lineage of H5N1 bird flu was transmitted to a child in Hong Kong who died of respiratory problems. This was the first of a number of recorded cases of transmission of this virus from poultry to humans.
Since then, the world follows the circulation of this virus with concern. Although we associate it [...]
Although we are acquainted with the influenza A (H1N1) and types such as H5N1 or H3N2, there are other influenza variants that infect humans and cause us concern.
The influenza H7 comprises various lineages, H7N7, H7N3 and H7N2 are those who knowingly infect humans. Some lineages are not very pathogenic (LPAI) and others highly pathogenic (HPAI), [...]
The impression that the flu appears during winter is very common but does it have any real basis?
In a broad way and with many exceptions, infectious diseases may be divided into acute and chronic. The acute infection occurs when the virus quickly infects the host, causes symptoms, is or is not transmitted and the disease [...]
If you think that all problems are solved after you have read all about the long vaccine production, you’re wrong. There is still the issue of distribution:
As the vaccine manufacturing process is slow and continuous, it is not possible to produce enough doses for everyone. Nowadays, our yearly vaccine production is of 700 to 900 [...]