We tend to hear so many warnings from government and the media that there is a tendency towards skepticism among many people. In some cases this turns into outright denialism, such as with the number of conservatives who outright deny the scientific consensus on climate change. While comments here are hardly representative of the population at large, noting two different comments to the previous post (from different parts of the political spectrum) questioning the attention paid to swine flu I have decided to briefly explain why this story really is a big deal.
One commenter writes, “I remember the bird flu and the outbreaks of normal flu before and after, too. At certain times of the year, people get the flu. Is this really news anymore?” The potential of a pandemic is far more significant than a normal influenza outbreak. Infectious disease and pubic health experts have been concerned for years about the dangers of an influenza pandemic comparable to the 1918 pandemic which cost a tremendous number of lives worldwide. The current swine flu outbreak may or may not turn into a pandemic, but there is reasonable concern for the potential of this happening. The World Health Organization ranks the risk of pandemic on a scale of one to six, with six being a full-scale pandemic. Currently the swine flu outbreak is rated at four, but it looks like the WHO is getting close to moving this up to a five.
During a normal seasonal influenza outbreak there’s a tremendous number of people who are immunized against the expected influenza strains for that year. Even those who have not received the influenza vaccine are partially protected by herd immunity. Having less people in the community who are susceptible to the infection makes it harder to spread, reducing the risk for those who have not been vaccinated. In contrast to normal influenza outbreaks, we do not have large numbers of people immunized against the swine flu. (I have seen some speculation that those who have received influenza vaccines on a regular basis have received immunizations against a large number of influenza strains and might have some partial immunity, but we certainly cannot count on this).
One feature of this infection might also make it potentially more serious than other influenza epidemics. Many of the more serious cases have occurred among young adults, as opposed to among the higher risk individuals who often suffer the most in influenza outbreaks. There is speculation that the more serious consequences of this strain come not from the initial infection but from the response of one’s immune system. Paradoxically this might make young healthy people with strong immune systems the ones at greatest risk.
Another consequence of influenza is the development of secondary bacterial infections when people are weakened by the flu. Overuse of antibiotics has increased the risk of the selection of bacterial strains which are resistant to conventional antibiotics.
Our patterns of travel make it more difficult to control a potential pandemic. The ideal way to contain an epidemic is to identify the outbreak in its first location and contain it there. It is far too late for that. The amount of air traffic from Mexico and around the world has spread the virus around the world, with confirmed cases in seven countries, with this number expected to rise quickly. As of 11:00 a.m. today the Center for Disease Control reports ninety-one laboratory confirmed cases in the United States. These are in ten states (Arizona, California, Indiana, Kansas, Massachusetts, Michigan, Nevada, New York, Ohio, and Texas). The largest number of cases are in New York City (51). The first death has been reported in Texas.
There might be some tendency to see an increase to only ninety-one confirmed cases as trivial, but we have no idea how much this will increase. The incubation period is two to seven days, meaning that there can still be many people who will turn out to have the disease from contact which occurred even before news broke of this infection last Friday. The bigger question is how much it will spread in different communities.
At this point we do not know how severe an illness we will be seeing. Initial reports out of Mexico suggested that the virus might be more deadly than it now appears to be. Even when there were reports of over one hundred deaths it was difficult to interpret this as we had no accurate count of overall cases. It now appears that these reports were exaggerated, with the WHO officially reporting only seven deaths in Mexico.
The considerable amount of media attention might actually be helpful in reducing the risk of pandemic. Simple precautions such as washing hands (including use of products such as Purell when hand washing is not practical) can greatly reduce spread. Knowledge of the existence of the virus could increase the chances that those infected do remain at home and avoid contact with others. Besides taking prudent action to avoid infection, it would also be advisable to be prepared with supplies such as food in one’s home should there be a serious outbreak in one’s community. The more people avoid public places in case of such an outbreak, the more likely it will remain limited.
At this point we do not know how serious a problem there will be. It is important not to panic, but also not to write this off as a meaningless scare should this not turn out to be a serious problem this year. The same concerns which cause infections disease specialists to be concerned about the risk of a pandemic exist, and we can still face such problems in the future. It also must be kept in mind that we are at the end of the usual influenza season and we might stop seeing this strain as we stop seeing other types of flu this time of year. It remains possible that the swine flu will return during next year’s influenza season, but that would leave plenty of time to develop vaccinations.
