What is swine flu?
The World Health Organisation (WHO) says the H1N1 influenza virus, or swine flu, is a highly contagious acute respiratory disease of pigs, caused by one of several swine influenza A viruses.
The virus is spread among pigs by aerosols, direct and indirect contact, and asymptomatic carrier pigs. Death rates from the virus are relatively low – between one and four per cent, according to the WHO. Outbreaks in pigs occur year round, with an increased incidence in the fall and winter in temperate zones. Many countries routinely vaccinate swine populations against swine influenza.
Although swine influenza viruses are normally species specific and only infect pigs, they do sometimes cross the species barrier to cause disease in humans.
How do people become infected?
People usually get swine influenza from infected pigs, however, some human cases lack contact history with pigs or environments where pigs have been located. Human-to-human transmission has occurred in some instances but was limited to close contacts and closed groups of people.
What are the symptoms of swine flu?
Symptoms are similar the normal human strains of the flu virus, including fever, cough sore throat and body aches. However those symptoms can worsen to include severe pneumonia that can result in death, the WHO says.
Why is the H1N1 virus called swine flu?
This virus was originally referred to as swine flu because laboratory testing showed that many of the genes in this new virus were very similar to influenza viruses that normally occur in pigs in North America. But further study has shown that this new virus is very different from what normally circulates in North American pigs. It has two genes from flu viruses that normally circulate in pigs in Europe and Asia and avian genes and human genes. Scientists call this a “quadruple reassortant” virus.”
Is it safe to eat pork meat and pork products?
Yes. Swine influenza has not been shown to be transmissible to people through eating properly handled and prepared pork (pig meat) or other products derived from pigs. The swine influenza virus is killed by cooking temperatures of 160°F/70°C, corresponding to the general guidance for the preparation of pork and other meat.
Which countries have been affected by outbreaks in pigs?
The disease is considered endemic in the United States. Outbreaks in pigs are also known to have occurred in North America, South America, Europe (including the UK, Sweden, and Italy), Africa (Kenya), and in parts of eastern Asia including China and Japan.
Is there a risk of a pandemic?
It is likely that most of people, especially those who do not have regular contact with pigs, do not have immunity to swine influenza viruses that can prevent the virus infection. If a swine virus establishes efficient human-to human transmission, it can cause an influenza pandemic.
Is there a human vaccine?
The WHO says there is no vaccine to contain the current swine influenza virus causing illness in humans. It is not known whether current human seasonal influenza vaccines can provide any protection.
What drugs are available for treatment?
Antiviral drugs for the normal flu virus have been effective in preventing and treat
the illness. There are two classes of such medicines:
1. Adamantanes (amantadine and remantadine)
2. Inhibitors of influenza neuraminidase (oseltamivir and zanamivir).
Most of the previously reported swine influenza cases recovered fully from the disease without requiring medical attention and without antiviral medicines.
However the WHO says so viruses develop resistance to the antiviral medicines, limiting the effectiveness of treatment. The viruses obtained from the recent human cases with swine
Flu in the United States were sensitive to oselatmivir and zanamivir but resistant to amantadine and remantadine.