Influenzas: Avian Flu, H1N1 (Swine flu) and other upper respiratory viral illnesses
Almost annually, there is a warning about a new flu strain that could impact on travelers. Often people forget that the seasonal influenza kills tens of thousands of people each year in North America. So every year it is wise to get an influenza vaccine.
The vaccine used changes yearly based on the changes in the virus at the end of the previous flu season. There are typically two attenuated (i.e.,dead) influenza viruses that are used in each vaccine. The vaccine is an educated guess about the nature of the upcoming flu season.
Viruses mutate rapidly, so the vaccine effective for one year isn’t for the next. And the flu viruses that infect people often trade genetic material with avian flu viruses and swine flu viruses. Sometimes the mutations make the flu more serious either because so few people have any immunity so it sweeps through the population or because it is more severe and produces more serious secondary infections, such as pneumonia.
Contagion and prevention: Getting an annual flu vaccine can reduce your chances of catching the seasonal flu. Influenzas are spread through person-to-person contact, most often via airborne droplets or touch. While coughing and sneezing get the most attention, the virus is easily spread via the hands. Thus, careful and frequent hand washing is an important preventive measure. Be careful not to touch your eyes, nose or mouth, as all can be an entry point for viruses on your hands. Remember that touching surfaces touched by someone who is ill is a direct transmission route. Carry antiseptic hand wipes with you, but take time to wash your hands with soap and water frequently, especially before eating.
Airplanes, due to the dryness of the air and the fact that the air is re-circulated can make an airplane a prime environment for the transmission of viral illnesses. There is little evidence that facemasks protect from airborne viruses. However, if one has a cold or influenza, a facemask can help protect others.
So what can you do on an airplane to minimize your risk of contracting influenza? Take along antiseptic hand wipes. You may wish to clean the armrests, tray table and other surfaces by your seat. Do use the hand wipes to clean your own hands especially before eating. Stay well-hydrated.
So what about the avian flu, H1N1 (swine flu), etc? What makes them different? Why is the media inciting so much panic about them?
Influenza viruses vary in many ways, some are easy to transmit from one person to another, and some are very difficult to transmit. Some are quite virulent, causing more severe symptoms and more severe complications. So, for instance, the Avian flu is quite difficult to transmit person to person, the vast majority of cases have been transmitted via direct contact with sick or dead birds or their droppings.
But Avian flu is quite virulent, and most of the people we know of who contracted it died. There may be more who lived, but the cases may not have been reported. The Avian flu has been mostly confined to areas of southern China and parts of Vietnam. There have not recently been reported cases of the Avian flu, but since we know that the virus is still active in various bird populations, it is expected that it or a variation of it will return.
The latest flu to worry people is a strain that was first detected in Mexico where it caused a number of deaths. It was initially titled “swine flu” as it carries some genes from swine flu viruses, some avian flu genes and some human flu genes. This flu has been of concern because it appears to be easily passed from person to person and there have been deaths among the young and healthy.
Seasonal influenzas, while causing deaths, mostly cause deaths among the elderly, infants and those who are already ill or have weakened immune systems. Influenza that kills young and healthy people has the potential to cause pandemics.
The pandemic cited as the type that public health officials worry about is the 1917-18 influenza. Millions died. Indeed, more people died of the flu than died in combat in World War I, which was raging at the time. This flu killed the young and healthy, and at times it killed within hours of the person falling ill. Some researchers believe that the rapid deaths among the young and healthy were caused by an overwhelming response by the immune system that then caused collapse of the person’s immune system. Usually flu deaths are related to complications such as pneumonia.
At present, it appears that the H1N1 flu is quite contagious but it does not appear to be very virulent. So the Center for Disease Control and World Health Organization are both keeping a close eye on the spread of the virus and any changes in virulence.
The CDC website is an excellent source of information about the influenza outbreak. It is updated frequently and it has links to the WHO pages on the outbreak.
