Update on H1N1 vaccine

Dipali Pathak
713-798-4710
loriw@bcm.edu

Dr. Paul Glezen answers questions about the H1N1 vaccine and the virus. The questions fall into six categories: general, symptoms and care, high risk factors, the virus itself, prevention, and the vaccine.

General

What is the situation right now?

Right now, the influenza activity is increasing at a high rate every week, and more and more people are infected. That means that we're going to see an increasing number of people with complications and even death over the next few weeks. Therefore, people should keep alert to availability of vaccine and get vaccine as soon as possible. And if they develop a flu-like illness, it might be important to seek medical care and get an antiviral to shorten course of the illness and reduce the chance that you'll spread it to your contacts.

Can you get the seasonal flu and the H1N1 virus?

It would be possible to get sequential infections. We're already seeing the novel H1N1, so it's likely going to precede the seasonal influenza this year. So I think they'll be sequential, but you could get both and that's why it's important to get both vaccines.

Symptoms and Care

What symptoms are we seeing with the H1N1 virus?

Typical symptoms of influenza with fever, general aches, headaches, sore throat and dry hacking cough.

What should you do if you have these symptoms?

Well, number one try to avoid contact with as many people as possible. So stay home from work and school. If you seek medical care it's important to get Tamiflu or some antiviral treatment because that will not only shorten the course of illness but reduce the chance you'll spread it to your contacts.

When should you worry about your fever?

Well, after a couple of days if the fever does not respond to the usual anti peretics like Tylenol or Ibuprofen-like drugs, then you should seek medical care or advice from your doctor.

When should you go to the hospital?

If you have any shortness of breath or, you know, chest pain it would be important to go to the emergency room and get checked up.

When should you go back to school or work?

If you've been treated with antivirals like Tamiflu, you can go back after three days if you are well. That is, you know, no fever and no cough, etc. If not treated, then it may take at least five days and even up to seven days. Probably best to be fever free for at least 48 hours.

High Risk Factors

Who is susceptible to getting the virus? Who is susceptible to having complications from the virus?

Well, in general, children have the highest attack rate, and this depends on two things. One, on your previous experience with that virus, whether it's vaccine or natural infection. And, your likelihood of having contact with somebody who's infected. So that means young children in daycare or school have a high risk of infection because of their susceptibility and their contacts. Older people don't have the same contacts, so their risk for infection is not as great, but if they have a chronic underlying condition, their risk of complications if they get infected might be very high.

What are the different types of underlying conditions that put you at a higher risk?

Almost any chronic underlying condition like diabetes or heart disease or chronic lung problems like asthma or chronic bronchitis or emphysema will put you at increased risk.

What should you do if you have an underlying condition and you think you have the H1N1 virus?

You should seek medical care.

The Virus Itself

How long does the virus live on a surface?

Depends on the surface and the conditions, but it may remain viable for a couple of hours or more. But that doesn't mean it's necessarily transmissible from that surface even though you can isolate the virus.

How long does the virus live in the air?

Again, it's a matter of just a few hours, but that may be long enough to transmit it since when you breathe in the virus it takes a very small dose to produce an infection. In contrast, if it's a direct contact it takes a fairly large dose. So there's a big difference in susceptibility depending on how the virus is transmitted.

Prevention

What can you do to keep from getting the virus?

Well, number one is to get vaccine as soon as it's available, that's the most important thing. But if you can, you know, avoid contact with people who have symptoms of the flu, which means avoiding crowds that you don't necessarily have to join.

Is a mask helpful? If so, when should you use one?

A mask can be helpful both for a person who has symptoms who has to have contact with people, say in a clinic, or for people who are attending them it may give some protection. It also sort of alters behavior, so that you're not as likely to touch the face, etc.

The Vaccine

Could you still get the H1N1 virus even with the vaccine?

It's possible. The vaccine's not 100 percent, but it should be about 80 percent effective in healthy people.

Does the vaccine take effect immediately?

The live attenuated vaccine, which is given by nasal spray, gives almost immediate protection. But the shot requires twelve to fourteen days to build up the antibodies that would give you protection.

Do you have additional questions? Let us hear from you.