H1N1 (Swine Flu) Updated Key Points

H1N1 (Swine Flu)
Updated Key Points
April 31, 2008: 10:47 AM ET

CLEARED FOR TODAY; NUMBERS ARE EMBARGOED FOR PUBLIC RELEASE AT 11 AM ET ON THE WEB.

Situation Update

• CDC is reporting 141 human infections with H1N1 (swine flu) in the United States. (Yesterday, CDC reported 109 cases reported.)
• The list of states with the numbers of people who are confirmed cases is updated daily at 11am at www.cdc.gov/swineflu.
• Human infections with this new virus have been confirmed in 19 states at this time.
• The nation experienced its first death from this outbreak in the state of Texas in a 22-month-old child on Wednesday, April 29.
• There are additional reports of ill and hospitalized patients.
• But at this point, we need to move away from the focus on numbers.
• As I have been saying, we do expect that we will see more cases, more hospitalizations and more deaths from this outbreak over the coming days and weeks.
• Influenza is always serious – each year, in the United States, seasonal influenza results, on average, in an estimated 36,000 deaths from flu-related causes.
• This outbreak certainly poses the potential to be at least as serious as seasonal flu, if not more so.
• Because this is a new virus, most people will not have immunity to it and illness may be more severe and widespread as a result.
• The picture on the world stage is more somber too.
• On Wednesday, April 29, the World Health Organization raised the worldwide pandemic alert level to Phase 5.
• A Phase 5 alert is a “strong signal that a pandemic is imminent and that the time to finalize the organization, communication, and implementation of the planned mitigation measures is short.”
• This change, and any subsequent increase in the WHO alert phase, would not change the U.S. response to this emergency. We are fully engaged in implementing the national pandemic response plan.

This is indeed sobering, but it’s important to keep in mind that we are not helpless.
What we are doing:

The Federal Government is mounting an aggressive response to this outbreak.

• CDC’s goals during this public health emergency are to reduce transmission and illness severity, and provide information to assist health care providers, public health officials and the public in addressing the challenges posed by this newly identified influenza virus.
• To this end, CDC continues to update guidance continuously.
• Yesterday, we issued guidance for HIV-infected adults and adolescents, for pregnant women, interim guidance for airlines regarding flight crews arriving from domestic and international areas affected by swine influenza.
• And early this morning we issued interim guidance on school closures.
• This guidance includes recommendations on school dismissal for K – 12 schools and closure of child care programs and facilities.

• School dismissal and childcare closures are an important part of a comprehensive, layered mitigation approach aimed at reducing disease transmission and associated morbidity and mortality during the 2009 H1N1 virus outbreak in the US.
• I urge to you visit the CDC website at http://www.cdc.gov/swineflu/ for more information or call 1-800-CDC-INFO.
• This is a rapidly evolving situation and guidance should be considered interim and will be updated frequently. 
• In addition, yesterday, we issued two MMWR Dispatches.
• One describing the initial outbreak of H1N1 in Mexico that is available at http://www.cdc.gov/mmwr/preview/mmwrhtml/mm58d0430a2.htm?s_cid=mm58d0430a2_
• Findings indicated that transmission in Mexico involves person-to-person spread with multiple generations of transmission. The clinical spectrum of illness is not yet well characterized in Mexico.
• The second MMWR Dispatch was on an outbreak of H1N1 infections is a school in New York City – so far the largest reported cluster of H1N1 cases in the United States.
• This report suggests that these high school age students have similar respiratory and fever symptoms as seasonal flu, but , in addition, about half had diarrhea, which is more than expected in seasonal fllu.
• This report is available on the MMWR website at http://www.cdc.gov/mmwr/preview/mmwrhtml/mm58d0430a1.htm?s_cid=mm58d0430a1_e
• Everyday, we learn more about this virus and what we learn will continue to inform the actions that we take in response.
• CDC has developed a real-time RT-PCR Detection Panel to expand and maintain the operational capabilities of public health or other qualified laboratories by providing a detection tool for the presumptive presence of this new influenza A /H1N1 virus.
• Nationwide distribution of this diagnostic test begins today.
• This will enable states to increase their capacity to test at the state level.
• In addition, distribution of antiviral drugs, personal protective equipment, and respiratory protection devices from CDC’s Division of the Strategic National Stockpile (SNS) to all 50 states and U.S. territories continues.
• The Strategic National Stockpile has 49.9 million regimens of antiviral drugs. Six million of this total quantity is designated for specific purposes (i.e., containment) and the remaining 44 million are allocated to the public health emergency preparedness project areas, based on their population.
• The SNS deployment includes approximately 11 million antiviral regimens, masks, N95 respirators, Gowns, Gloves and face shields.
• Deployment to 20 states or project areas has been completed.  This total includes: including the following states in the last 11 hours:
• Chicago
• Maryland
• Utah
• Oklahoma
• Florida
• LA County
• California
• Arkansas

Deployment to 28 states or project areas is ongoing. SNS estimates completion by May 3.
There are currently 50 CDC staff persons deployed in the field to support the outbreak response.

H1N1 (Swine Flu) Virus Laboratory Testing

• The hallmark of influenza viruses is their ability to undergo constant and dramatic change. 
• Many different animals and, of course, humans get infected with influenza viruses, but the viruses generally stick with one species or another. 
• However, some times flu viruses jump from one species to another and, sometimes viruses from different species can infect the same host and result in a new combination of virus genes. 
• This last scenario is what happened and resulted in this new H1N1 virus. 
• I want to tell you a little bit about what the laboratory has found from exploring this new swine influenza A (H1N1) virus.
• This is a very unusual virus. This particular genetic combination of influenza virus segments has not been recognized before in the U.S. or elsewhere.
• This virus is a quadruple-reassortant virus, meaning that it contains genetic pieces from four different virus sources.
• We have some gene segments that are North American swine influenza viruses (that we call North American lineage);
• Some gene segments are North American avian influenza viruses (these are avian influenza viruses that circulate in birds in North America and we call North American lineage);
• One gene segment is from a human influenza virus; and
• Two gene segments that are normally found from swine influenza viruses in Asia and in Europe. 
• Testing of a number of the virus samples submitted to CDC show that they are very similar, which mean that they likely originated from the same source.
• The good news is that our laboratory testing has found no 1918-like markers for that are associated with increased risk of severe disease and death in this H1N1 (swine flu) virus.
• This is an important finding because it means that this H1N1 (swine flu) virus does not have similar characteristics to the 1918 pandemic virus that resulted in millions of deaths worldwide.
• Additionally, in this H1N1 (swine flu) virus our laboratory has not found the high pathogen markers that were previously identified in the avian influenza A (H5N1) virus that has caused human infections and deaths in people in other countries. 
• Vaccine
• We are aggressively taking those early steps in the vaccine manufacturing process, working closely with manufacturing and the rest of the government.
• Vaccines are a very important part of a response to influenza, including novel influenza that may become pandemic.
• CDC has isolated the new H1N1 virus and is working to make a vaccine virus that can be put into industry's hands to scale up for production of a vaccine.
• There are many steps involved with producing a vaccine and we are committed to going forward with the NIH, and FDA, BARDA, and the manufacturing community, to see about developing a full scale vaccine production.
• The first step in developing a vaccine is getting a good “seed” virus.
• A high-yield “seed” virus is a sample of the virus that is used to grow the virus in mass quantities. Parts of the virus particles important for the immune response to a vaccine (called the virus antigens) are then purified to make the vaccine.
• CDC is working to develop a vaccine virus specific to the recent human cases of H1N1 (swine flu).
• Making a vaccine virus is accomplished by combining genes from a virus that grows very well in eggs with genes that carry the immunizing antigens from the H1N1 (swine flu) virus.
• Without a high-yield vaccine virus, it can be very difficult to manufacture vaccine to protect against the particular virus.
• We are taking two approaches to creating the vaccine virus:
• We have grown the viruses in eggs and sent them to the New York Medical College and other WHO Collaborating Centers for production of the high-yield seed in eggs.
• We have used molecular genetic techniques to make a DNA copy of the genes encoding immunizing antigens from the influenza A (H1N1) swine origin virus. We are currently combining these genes with those of the high-yield virus to obtain seed virus for vaccine production. This process is known as reverse genetics. Parallel work is being conducted by FDA and WHO Collaborating Centers.
• We estimate that it will take about two more weeks to create a high-yield vaccine virus, depending on its ability to grow in eggs.
• Once we have a vaccine virus it will be sent to the vaccine manufacturing companies.

• The companies need 8 to 11 weeks to make small lots of vaccine for testing to see whether the vaccine virus works well in the manufacturing process.

• These lots are studied through NIH-sponsored trials that look at the best dosing; whether we need something called an adjuvant that can help with the immune response will also be evaluated.
• CDC also has provided the H1N1 virus to a private vaccine manufacturer for development of a live attenuated vaccine virus for use as an intranasal spray vaccine.
• But influenza vaccine production is pretty unpredictable.
• And we really need to be patient, and make sure that we're taking the careful steps to produce vaccine the way it's supposed to be.
• If things go well, and we develop a full scale production, it would be several months until the vaccine is available.
• By traditional methods, it takes about six months to produce large quantities of influenza vaccine.
• So the vaccine is an important tool for the future.
• But a vaccine won’t be available for some time yet, so it’s important to remember that we have other weapons in our arsenal in the fight against influenza in the meantime.

Public:

• We do have antiviral medications in our arsenal against flu.
• The prioirity use for influenza antiviral drugs  during this outbreak is to treat severe influenza illness.
• Influenza antiviral drugs are prescription medicines (pills, liquid or an inhaler) with activity against influenza viruses, including swine influenza viruses.
• Antivirals work differently than vaccines or antibiotics and need to be taken according to your doctor’s directions.
• Vaccines prepare the body’s own immune system to fight the virus, and can keep you from becoming sick.
• Antiviral drugs are prescription medications which work by decreasing the spread of flu viruses in the respiratory tract. 
• In addition to being in our national stockpile, these drugs are available in drugstores by prescription. They are routinely used in the treatment of seasonal influenza.
• There are two influenza antiviral medications that are recommended for use against swine influenza. These are oseltamivir (trade name Tamiflu ® and zanamivir (Relenza ®).
• Influenza antiviral drugs work best when stated soon after illness onset (within two 2 days), but treatment with antiviral drugs should still be considered after 48 hours of symptom onset, particularly for hospitalized patients or people at high risk for influenza-related complications.
• Here in the United States, we have invested in our strategic national stockpile and we do have on hand quite a bit of antiviral drugs.
• You have a role in protecting yourself and your family.
• Stay informed. Health officials will provide additional information as it becomes available. Visit www.cdc.gov
• Everyone should take these everyday steps to protect your health and lessen the spread of this new virus:
• Cover your nose and mouth with a tissue when you cough or sneeze. Throw the tissue in the trash after you use it.
• Wash your hands often with soap and water, especially after you cough or sneeze. Alcohol-based hand cleaners are also effective.
• Avoid touching your eyes, nose or mouth. Germs spread this way.
• Try to avoid close contact with sick people.
• If you are sick, do not go to work or school for 7 days or until your symptoms go away (whichever is long). This is to keep from infecting others and spreading the virus further.
• Follow public health advice regarding school closures, avoiding crowds and other social distancing measures.
• If you don’t have one yet, consider developing a family emergency plan as a precaution. This should include storing a supply of extra food, medicines, facemasks and other essential supplies.

What Communities Can Do:

• At the local level, we are hearing reports that some schools are being closed in various states.
• Community-level social distancing efforts to slow the spread of disease will be in an important tool at our disposal against this swine influenza outbreak.
• Simply put ‘social distancing’ is a way of ‘keeping our distance’ from each other to lessen the spread of flu.
• So communities may want to consider plans for and measures that can promote social distancing like school closures, teleworking, shift work and other social distancing measures.
•  

Recommendation re: Mexico Travel

• On April 27, CDC issued a travel health warning recommending that travelers postpone all non-essential travel to Mexico until further notice. That remains in place.
• We are recommending that people avoid non-essential travel to Mexico at this time.
• If you must travel to Mexico, there are steps you should take to reduce your risk of infection.
• Visit http://wwwn.cdc.gov/travel for the latest information on travel.

Clinicians:

• Laboratory testing on these viruses so far indicate that they are susceptible (sensitive) to oseltamivir and zanamivir. (This virus is resistant to amantadine and rimantadine so these drugs will not work against these swine influenza documents.)
• Clinicians should continue to consider H1N1 infection in the differential diagnosis of patients with acute febrile respiratory illness who have either been in contact with persons with confirmed swine flu, or who were in one of the U.S. states that have reported H1N1 cases or in Mexico during the 7 days preceding their illness onset.
• Patients who meet these criteria should be tested for influenza. At this point, specimens should be sent through the public health laboratory systems to conduct testing specific for H1N1 virus.  
• Influenza antiviral drugs work best when started soon after illness onset (within two 2 days), but treatment with antiviral drugs should still be considered after 48 hours of symptom onset, particularly for hospitalized patients or people at high risk for influenza-related complications.
• CDC continues to issue and update interim guidance daily on the website and through health alert network notices as information becomes available.
• Clinicians should visit http://www.cdc.gov/swineflu/guidance

Other Key Points
Virus Name

• This is a rapidly evolving situation and current guidance and other web content may contain variations in how this new H1N1 virus is referred to. Over the coming days and weeks, these inconsistencies will be addressed, but in the interests of meeting the agency's response goals, all guidance will remain posted and new guidance will continue to be issued. CDC’s highest priority is on providing guidance to save lives and limit the impact of this outbreak on public health.

Pork

• Swine influenza viruses are not transmitted by food.  You cannot get swine influenza from eating pork products.

Seasonal Flu Vaccine
Production of the seasonal flu vaccine for next season is nearly complete and will be completed. Seasonal flu is responsible causes an estimated 36,000 flu-related deaths and 200,000 flu-related hospitalizations in the U.S. each year. Seasonal flu vaccine is always a public health priority.