Posts Tagged ‘virus’

SARS déjà vu?

May 11th, 2013

Last month the World Health Organization (WHO) began to receive reports of human cases with SARS-like infections caused by a new coronavirus. According to WHO, 30 cases of this new illness have been found and 60% of the infections have been fatal. So far, the cases have been limited to Saudi Arabia, Qatar, Jordan, the United Arab Emirates, the UK and France. Symptoms are pretty serious and include fever, cough and shortness of breath. Most of the people infected have required hospitalization. It looks like the virus spreads person to person, but scientists don’t yet know enough to say for sure.

CDC, WHO, and other public health organizations are looking into all severe acute respiratory cases, especially those with recent travel to the Arabian Peninsula to identify any new cases of the virus and learn more about how it might be spreading. No cases have been found in the US.  Here’s some up to date information if you’re interested in learning more.

Yesterday I blogged about what we’ve learned since we first discovered SARS. 

 

SARS… A 10-Year Retrospective

May 10th, 2013

This Spring marks 10 years since Severe Acute Respiratory Syndrome (SARS) arrived on the global public health scene.  It started as a mystery illness in SE Asia- without name, origin, or cure in February of 2003.  The CDC immediately began working with the World Health Organization to investigate the outbreak.  Public health scientists across the globe scrambled to understand and contain this health threat… which ultimately infected more than 8,000 people- killing about 10% of them. 

By March of 2003, the CDC had confirmed that the disease wasn’t caused by an influenza virus, but they didn’t know the culprit…  so they named it after the symptoms (Severe Acute Respiratory Syndrome) rather than the causative agent (it turned out to be a new Coronavirus).  March of ’03 also marked the time when the CDC figured out that the virus was spread via face-to-face human contact.  That’s also when the CDC and WHO recommended strict infection control measures including hand washing, gloves, avoiding sharing household items, and limiting interaction between ill patients and others. 

Exactly 10 years ago today CDC figured out that there were some “super-spreaders” that were a particular problem with the growing epidemic.  May ’03 also marked the month in which the investigation and public health and clinical interventions matured- bringing the full weight of the global public health and clinical management system to bear on the virus.  Interventions like concise case definitions and reporting standards, laboratory diagnostic tests, travel restrictions, and clear clinical management and infection control guidelines all worked together to eradicate the virus by the Summer of 2003. 

The forensic investigation continued for a few months after the virus was eradicated.  The investigation kept pointing toward an animal called a Civet as the source of the new Coronavirus.  A SARS-like virus had been isolated from civets captured in areas of China where the SARS outbreak originated and sold in live animal markets.  It’s a mammal with a catlike body, long legs, a long tail, and a masked face resembling a raccoon or weasel.  By January of ’04 it was pretty clear that a Civet was the probable source, and the CDC issued a  “Notice of Embargo of Civets”, which banned the importation of civets into the US. The ban is currently still in effect.  China also implemented some control measures on them. 

Interested in the whole story?  Check out “Remembering SARS: 10 Years Later” on the CDC’s website.

H7N9 Influenza

April 5th, 2013

This week the WHO announced that several people in eastern China are infected with a newly mutated bird influenza virus called H7N9. All are in critical condition and some have died… but importantly the cases don’t appear to be linked- meaning it’s probably not from human to human transmission (that’s good). The World Health Organization website has more detail including answers to some Frequently Asked Questions

Global Influenza surveillance is a key public health tool… because early warning gives the global public health system an opportunity to squelch the outbreak before it breaks loose and causes a pandemic. It also gives us a head start on interventions and planning.   BTW… in case you were wondering, the H stands for hemagglutinin and N stands for neuraminidase- which are proteins on the virus’s surface. The numbers stand for the kind of protein for each letter.

The Coronavirus

March 21st, 2013

There’s never a dull day in public health! Things are changing all the time– from new interventions to help folks stay or be more healthy to the discovery of a new virus. Recently, folks on the other side of the world documented a new Coronavirus that can be transmitted person to person. It was first discovered last September when doctors were looking into the death of a man in Saudi Arabia – since then, 15 cases have been laboratory confirmed. All the cases of this virus have ties to the Middle East – either through travel or contact with someone who travelled there. The CDC updated its treatment protocol to include questions about travel to the Mid-East for people who develop a severe, acute lower respiratory infection.

This Coronavirus causes a lower respiratory infection and is pretty strong, 9 of the 15 people who contracted it – died… but in general the Coronavirus is pretty fragile and many of us catch and defeat the virus in our lifetime. It only lives outside of a body for about 24 hours. Human Coronaviruses were first discovered in the 1960’s and they have their name because of the crown like spikes on the surface. One of the most notable Coronaviruses is SARS which hit the world with a splash when it first appeared in 2003. No documented SARS cases have been seen since 2004.

Influenza Still Increasing in AZ

January 25th, 2013

Yesterday afternoon’s weekly flu report shows that influenza is still circulating widely in AZ…  with a steep increase in the last couple of weeks.  The strain that’s circulating is mostly Type A - H3N2 which can be more severe than the 2009 H1N1, especially for seniors. There are plenty of B strains going around too.  But you can still find a vaccine through Stop the Spread AZ – just be sure to call the place first to make sure they still have it and if you need an appointment.  By the way- this year’s vaccine is still a perfect match for the circulating strains.  The best prevention besides getting vaccinated is to wash your hands and make sure you cough or sneeze into your sleeve instead of your hand.  Most importantly…  don’t send your kids to school sick and don’t go to work sick either.

RSV on the Upswing in AZ

December 12th, 2012

We’re off to an early start with the flu and RSV season this year with more cases reported in November than in previous seasons. Respiratory syncytial virus (or RSV) is a respiratory virus that mainly affects little kids and circulates during the winter. There’s no vaccine for RSV- but for those babies that are at highest risk (premature infants), doctors can give a preventive treatment throughout the season. The number of cases is still pretty small (about 100 so far this year), but we’ve had a 40% increase in cases over last year. That doesn’t always mean that there will be more cases this season, but it may just be a sign that our cases will happen earlier. 

Once RSV infections begin to increase we usually have high levels for a few months. Doctors who give RSV antibody to high-risk infants might want to start incorporate this info into their treatment plans soon- and it’s time for hospitals to start thinking about implementing their RSV prevention plans. Our flu numbers have also been high for this season (cases this week double from last week), so now is the perfect time to go out and get your flu shot. If you want to keep a watch on the numbers, our flu and RSV website has a host of useful information including periodic reports.

 

We Nailed Smallpox- Why Not Polio?

October 24th, 2012

Today is World Polio Day so I thought I’d throw together this post to give you an update on where we are in the global eradication effort.  2012 has been a good year so far- as the global public health system has made some real progress.  This year we’re down to only 3 countries with cases (Afghanistan, Nigeria and Pakistan) and only 200 cases.  We’re closer than ever to global eradication of this nasty disease.  The world was about this close to eliminating polio in the 2000′s, but political strife and other issues in West Africa turned the tide and set the eradication clock back.  

A couple billion kids around the world have been vaccinated against polio in the last decades - resulting in a 99% decrease in global polio cases.  The Bill and Melinda Gates Foundation has been adding support to the new push to eradicate by working with the Global Polio Eradication Initiative.  

You might wonder why public health was able to get rid of Smallpox but not Polio (yet).  It’s basically because Polio is spread through via the “fecal-oral” route.  That means that folks shed the virus in feces…  and other people catch the disease through contaminated water (or food).  That means that we need to use mass vaccination efforts to prevent more cases rather than the more cost effective and efficient “ring vaccination”  approach that we used to eradicate Smallpox.  With Smallpox…  we could track down cases quickly and vaccinate contacts and villages to prevent the spread- since it went person to person. 

Looking for a book to read about one of public health’s biggest achievements?  You’ll enjoy a new book written by Dr. Bill Foege called House on Fire: The Fight to Eradicate Smallpox.

Flu Down Under- 2012

August 24th, 2012

The Southern Hemisphere has its flu season during our Summer- so every year around now we watch influenza activity “down under” to get an idea of what we might expect for our upcoming flu season.   Here’s the scoop right now.  Flu south of the equator has already peaked and continues to decline.  There’s been a lot of variation in the dominant viruses in each country this season.  Many South American countries have mostly had the H1N1 “pandemic strain” while others like Southern Africa, Australia and New Zealand all had a lot of influenza A (H3N2), with co-circulation of influenza B.  You can check out more on the World Health Organization’s main influenza website and the Australian Health Ministry’s surveillance website.  

The formula in this year’s US vaccine is a good match for what’s been circulating in the Southern Hemisphere so far this year (Influenza A H3N2 and H1N1, and influenza B).   Some of the manufacturers of the vaccine have already delivered some doses- and you’ll no doubt start seeing those “flu shots here” signs at a pharmacy near you shortly.

That Stubborn Whooping Cough

July 31st, 2012

Whooping Cough is making headlines again – with more than 18,000 cases in the U.S. and 600 cases so far this year in AZ.  You might wonder why we continue to have lots of whooping cough cases in the US and AZ when the other vaccine preventable diseases are real rare (e.g. measles, mumps etc.). 

Creating a vaccine for whooping cough is different than a vaccine for measles.  Whooping cough is a bacteria and measles is a virus – and that’s a big difference when it comes to making a vaccine that lasts.  That’s partly because virus generally have a pretty specific and predictable protein coat on their surface that makes it easier to create a vaccine that generates antibodies specific to the virus coat- like a lock and key.  Bacteria, on the other hand, are much larger and pose a bigger challenge when making a vaccine because the cell wall is way more complicated than a simple virus protein coat.  As a result- vaccines against viruses are generally more protective and last longer.  Likewise, when you get sick from whooping cough you’ll have temporary natural immunity- but you can still get it again (unlike some viruses such as measles). 

Anyway- it’s important to keep up the battle against whooping cough because of the danger it poses to babies.  We had one baby die earlier this year in Arizona.  Babies are just too young to fight the disease – they don’t have the immunity and they don’t have the ability to cough like children and adults do.  So it’s important for us to make sure that everyone around them has been vaccinated.  I talked about the importance of “cocooning” and our cocooning intervention strategies last summer in my Whooping it Up blog post.

H7N3

June 29th, 2012

Remember the 2009 H1N1 influenza pandemic?  That brand new virus that caused the pandemic was a combination of RNA from four different flu viruses – North American swine influenza, North American avian influenza, human influenza, and swine influenza virus typically found in Asia and Europe.  The natural laboratories for new influenza viruses that end up causing pandemics (like the ’09 pandemic) are birds and pigs- so it’s important to pay attention to new viruses that emerge in these species so interventions can be implemented to manage outbreaks and potentially prevent human outbreaks or even pandemics. 

Last week Mexican veterinary authorities found a new strain of influenza virus called H7N3 that has been infecting and killing large numbers of poultry at several large commercial farms.  This is the first major outbreak in Mexican flocks since the country battled H5N2 influenza virus in the mid 1990s.  Luckily, there are no human cases and no suggestion yet that it is a kind of virus that can infect humans- but it’s still important to follow up on  Follow-up report No. 1 (25/06/2012)

By the way- the Influenza virus strains get their names from compounds called hemagglutinin and neuraminidase.  The H in the name refers to the kind Hemagglutinin on the virus and the N stands for the strain of Neuraminidase on the virus.