Can you get SARS more than once?

Answer 1

The short answer:

If you are exposed to an identical version of the H1N1 flu that you had previously after you have recovered fully from it the first time, then your body should have developed immunity to all genetically identical H1N1 flu and you would not get it a second time. However, the flu can change by mutations and if it does change enough that the immune system no longer sees it as identical, then you would not have immunity to the mutated strain. This is a similar concept to why we need different seasonal flu vaccine every year.

The more detailed answer:

Not if it is the same strain or a very similar strain of the virus to which you were originally exposed. Once you have been infected, if you have a healthy immune system, your body has produced antibodies for the first infection, you will not get sick a second time because of the way our immune system in our bodies works.

This is a simplified explanation of that immunity process. Our body has the ability to determine when some organism has invaded and, if it has a match to that organism stored from a prior invasion, the immune system quickly makes up a lot of the attack cells that worked in the past and destroys the invading cells or virus particles. If it is a new invading virus, usually our body can make cells that can match just right to destroy the new invader in a week to ten days. It can sometimes do this even more quickly for bacteria and other microbes.

It is during the time period, when our body is matching and making the attack cells to "kill" the invader, that we feel sick until our body finds the key pattern of cells that will match and destroy that specific germ. Our body "remembers" the pattern each time it makes cells that work to kill germs, so any time that same germ comes along again, or even sometimes a similar one, our immune system wastes no time in getting rid of the invading organism, because it knows already what will work. That is why once we have had a flu virus like Swine Flu before, we won't get sick from it again. Our body will already know what cells to make and will send them out to destroy the invader even before it can make us feel sick.

This is also how vaccines help our bodies build up immunity or resistance to germs. The vaccine contains a dead or weakened form of the expected invader organism for our bodies to use as a template to create the right pattern of cells that will know how to neutralize or destroy the normal strength organism in the future if it tries to get in to make us sick after that.

However, if you are immuno-suppressed from transplant medications, chemotherapy, or diseases like HIV/AIDS, then the ability of the immune system to do its work to protect your body is weakened, and repeat infections by the same organisms could potentially occur since your body's ability to make and send the correct cells to your defense is impaired.

Because flu and cold viruses mutate readily, it is possible to catch different forms of swine flu after you have had one before that is not the same exact strain. If you contract a mutated strain, after already having had swine flu, your body may be able to fight it off easier through 'cross protection', i.e., already having dealt with a similar virus.

But even if your body can recognize it as very similar, and make the same cells as before, if the pattern of cells that your body remembers and sends to the defense does not fit the new strain of the swine flu well enough to destroy it, you may feel sick until the body figures out the perfect new pattern.

Your body remembers each new pattern to protect you again from that specific strain or strains that are very similar. It is believed that the current population aged 65 and older have some residual resistance to the A-H1N1/09 Swine Flu from having been exposed to a similar strain in the past (perhaps the 1930 strain). They are unusually unaffected by this influenza, when typically they are the most at risk with seasonal influenza strains.

While the immune system's ability to store patterns for previously encountered germs explains why older people do not get sick as often, or have as severe an illness as very young children and babies do, from most common colds and viral infections, if a brand new germ attacks them, then the elderly often have more trouble and can be very ill or even die from the more severe viral attacks, such as those caused by new or mutated seasonal influenza strains. Because of many older people's frailty, multi-system chronic diseases, and less robust immune systems, they can have more trouble creating new patterns.

Similarly, because infants and very young children have not had any prior exposure to the common germs, this is also why it is highly recommended that newborns be breast fed. If they are given mother's milk, at least for a short period after birth, it provides a safe way for their developing immune systems to learn the patterns for the kinds of infections that are around in their immediate environment. The antibodies are passed from the mother to the infant in the milk.

Information from the CDC about breast feeding your baby if you have swine flu:

"Because mothers make antibodies to fight diseases they come in contact with, their milk is custom-made to fight the diseases their babies are exposed to as well. This is really important in young babies when their immune system is still developing. It is OK to take medicines to prevent the flu while you are breastfeeding. You should make sure you wash your hands often and take everyday precautions... However, if you develop symptoms of the flu such as fever, cough, or sore throat, you should ask someone who is not sick to care for your baby. If you become sick, someone who is not sick can give your baby your expressed milk." (Infants 6 mo old or less can not be vaccinated yet.)

We can thank our amazing immune systems for our ability to avoid getting the same exact swine flu more than once.

According to the CDC:

Getting infected with any influenza virus, including 2009 H1N1, should cause your body to develop immune resistance to that virus so it's not likely that a person would be infected with the identical influenza virus more than once. (However, people with weakened immune systems might not develop full immunity after infection and might be more likely to get infected with the same influenza virus more than once.) However, it's also possible that a person could have a positive test result for flu infection more than once in an influenza season. This can occur for two reasons:

1. A person may be infected with different influenza viruses (for example, the first time with 2009 H1N1 and the second time with a regular seasonal flu virus. Most rapid tests cannot distinguish which influenza virus is responsible for the illness. And,

2. Influenza tests can occasionally give false positive and false negative results so it's possible that one of the test results were incorrect. This is more likely to happen when the diagnosis is made with the rapid flu tests.

Answer 2

According to InteliHealth - yes, scarlet fever can recurr. Check out this link...

http://www.intelihealth.com/IH/ihtIH/WSIHW000/35263/8477/579510.html

Answer 3

Yes, you can get SARS more than once. This is a viral respiratory disease caused by the SARS coronavirus and the only treatment for the disease are antibiotics.

Answer 4

yes