Science and the Swine Flu

You’ve likely heard news reports this week about the swine flu virus outbreak in Mexico. The swine flu or swine influenza produces regular outbreaks of respiratory disease in pigs and is caused by influenza type A viruses. Transmission of swine flu viruses between people has been reported in the past, but was limited to three people. Today, the World Health Organization (WHO) raised its pandemic alert to "phase 5", which means that people in at least two countries in one WHO region are spreading the disease [1]. This was done following an increase to "phase 4" several days ago because the virus was already widespread in differnet locations, with confirmations in Mexico, the United States, Spain and Scotland.

While the Centers for Disease Control and Prevention (CDC) has determined that the swine flu is contagious and is spreading from human to human [2], the WHO has indicated that most people infected with swine flu make a full recovery without the need for medical attention or antiviral drugs [3].

New Common Cold Virus Variant Deadly

Last week, the Centers for Disease Control and Prevention (CDC) reported that a new virulent strain of the common cold virus, adenovirus, has caused 10 deaths over the last 18 months [1]. The virus, identified as adenovirus serotype 14 (Ad14), is a rarely reported strain of adenovirus that can cause severe and even fatal respiratory illness. It’s unusual since adenoviruses typically cause non-lethal infections. According the the CDC report:

The cases described in this report are unusual because they suggest the emergence of a new and virulent Ad14 variant that has spread within the United States.

sneezing

Indeed, between the months of March-June 2007, Ad14 caused at least 140 respiratory illnesses in three states; Oregon, Texas and Washington [1]. More than 50 of those patients were hospitalized, including 24 who were admitted to intensive care units. Nine of those patients died, most from severe pneumonia. People of all ages have been affected, including healthy young adults, typically the group least susceptible.