April 24, 2009

UPDATE #4:
Swine Flu Outbreak Declared a Public Health Emergency

This is the influenza update as of Monday afternoon. It is appended to yesterday's report.

The number of confirmed cases of swine influenza in the United States has risen to 40.

The European Union has urged travelers to avoid unnecessary travel to the United States and Mexico due to concerns about possible exposure to the virus, but the Acting Director of the U.S. Centers for Disease Control, Richard Besser, countered that the travel restrictions were unwarranted.

No surprises have occurred today as the new influenza virus begins to move through the human population. The rest of the world has identified the U.S. and Mexico as places to avoid to try to slow the spread of swine flu, and they are correct to do so.

Please note, although U.S. health officials are not yet confronting the public with outright declarations to this effect, their statements are unanimous in confirming that the virus has already advanced too far to be contained. It may possibly be slowed in its advance by utilizing travel restrictions and infectious disease prevention measures, but swine flu's spreading throughout the general population is considered now to be all but inevitable.

We have been dealing with many questions from our corporate clients, and we will share this one as an example:

A woman who is employed by a Manhattan company presented this situation. Her mother lives with her, and works as a school aide at St. Francis Prep in Queens, the epicenter of the local outbreak. Mom had developed a runny nose, and with news reports was concerned that she may have been exposed to swine flu. She went to her doctor this weekend, and was told she just had seasonal allergies, and was sent home. But within five hours of returning home she had developed high fevers, aches, and a bad cough. She returned to her doctor who diagnosed probable swine flu, put her on Tamiflu, and sent her home to rest. She is not one of the 40 official cases on the swine flu list.

Already her mother is feeling better, but the woman has asked: Should I come in to work? Am I contagious?

No, she should not come to work, and yes, she is a contagious risk.

The incubation period for the virus is 24-48 hours. If the woman is symptom-free 2-3 days after her last exposure to her mother, she probably has escaped illness. However, her mother will continue to shed virus for up to 7 days after clinical improvement in her symptoms. If the woman is still living with her mother, she may need to wait a week after her mother is better before she can with confidence judge that she has escaped illness, and is not at risk of spreading the virus.

Part of the reason influenza cannot completely be contained is that we are contagious and spreading virus before we know we have been exposed. Common sense isolation measures should take into account the two-day incubation period, and also the shedding of virus for one week in adults and up to three weeks in children after influenza illness has resolved.