SITUATION REPORT
This summer has been a very active time for pandemic influenza in other countries, especially in the southern hemisphere where winter (their normal seasonal flu season) is now wrapping up. While the pandemic is continuing its global spread as it was expected in these areas, the percentage of persons requiring hospitalization or dying has not dramatically changed. What has happened during winter in the southern half of the globe may be our best guide as to what may happen in the US. The most important observation from this global perspective is that most of those infected have fully recovered in a week or so with no medical interventions. This has quieted most of the fears that the pandemic strain would either mutate to become more lethal, or recombine with other types of influenza (such as H5N1 “avian influenza”) to become a more dangerous virus. Even without a progression in the pathogenicity of H1N1, there is still a great deal of concern that over the next few months the US will be challenged by a surge in the demand for some types of medical services, such as emergency and intensive care. There will also likely be a significantly higher number of severe cases and fatalities compared to a “normal” flu season since so little immunity exists in the population. This was most recently punctuated by the release of a report from the President’s Council of Advisors on Science and Technology (PCAST) (http://www.whitehouse.gov/assets/documents/PCAST_Recommendations_and_Administration_Progress.pdf) which provided a plausible “planning scenario” in which 30-50% of the US population could become infected with H1N1, resulting in 1.8 million hospital or doctor visits, and 300,000 requiring intensive care. The rationale behind this observation is that although the pandemic H1N1 strain seems to have a case-fatality rate similar to that of the seasonal flu, the overall number of individuals affected will be larger due to a lack of immunity in the population. While this scenario is certainly “plausible” it is nearly impossible to establish how likely it is that the situation will be this severe– a point emphasized by the CDC press release in response to the PCAST report and the observation that the media was inaccurately reporting the planning scenario as a “forecast.”
With the progression of the pandemic, changes have occurred in how the public health authorities are observing its progress. First, most countries have appropriately stopped reporting confirmed cases. This has posed a challenge to the media, which has focused much of their reporting on tracking the number of new cases (the “denominator”) in affected regions. While this information was very important in the beginning of the pandemic to better define the early spread, what is more important now is understanding what communities are affected in an effort to keep track of how widespread the disease is on the global map (check out: http://www.who.int/csr/don/GlobalSubnationalMasterGradcolour_20090813_20090819.png). Secondly, in the southern hemisphere where it is late “winter” (or monsoon season, depending on the latitude) now, an interesting phenomenon has been observed. The predominant circulating flu virus is pandemic strain H1N1, compared to the expected strains of seasonal influenza which circulate during the winter. Where it was originally thought that the two types of influenza (seasonal and pandemic) would co-exist, it would appear that one has largely replaced the other. There is some evidence to suggest that although seasonal flu viruses will likely be present in the US this fall and winter, pandemic strain H1N1 may be the predominant strain. Since we do not know how many people in the U.S. were actually infected this past year already and may have immunity, and since we do not know exactly when an H1N1 vaccine will be delivered, there are many outstanding variables that could greatly affect how this will play out.
H1N1 VACCINE
Great efforts are being taken to make available an H1N1 vaccine for this fall, and the CDC has developed a list of those who will have priority access to the vaccine as it’s produced. The pandemic H1N1 vaccine will complement, but not replace, the seasonal flu shot that is recommended annually. Since this is a new vaccine which requires extensive testing, there is still some good potential for surprises and delays in the projected schedule for release and with the vaccination strategy released by the CDC. Clinical trials are now ongoing in adults and children, with the first phase of delivery of vaccine expected in October. Some countries are reportedly taking delivery of H1N1 vaccine as soon as this month. Either way, the priority list is an important way to regulate who will get the initially limited supplies in the U.S. as they appear. A vaccine is the most effective way to stop the spread of a pandemic, and this is the keystone of the U.S. response to H1N1. More info on this at: http://www.cdc.gov/h1n1flu/vaccination/statelocal/qa.htm. It appears that the H1N1 vaccination will consist of a series of two injections, and this is in addition to the seasonal flu shot, which is given once. It remains to be seen how the public will respond to this need for multiple injections for related viruses, and if there will be either great interest or disdain for the shots this year. How this vaccine strategy is marketed will be of critical importance. Some experts and surveys project a moderate to high demand (see: http://www.washingtonpost.com/wp-dyn/content/article/2009/08/19/AR2009081901585.html), while others feel that unless something changes to increase the public’s fear of H1N1, vaccines may go largely underutilized. This report provides recommendations by CDC's Advisory Committee on Immunization Practices (ACIP) regarding the use of vaccine against infection with novel influenza A (H1N1) virus. http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5810a1.htm?s_cid=rr5810a1_e
ANTIVIRAL MEDICATIONS
Another rapidly evolving and controversial issue is the use of antiviral therapies such as oseltamivir and zanamivir (Tamiflu® and Relenza®). While these were very popular medications that saw widespread use and high demand in the initial outbreak, the climate around the use of these medications is changing some. Initially, there was a large emphasis on the use of antivirals to curb the spread of the outbreak and to reduce symptoms in the relatively small number of patients affected. This week the World Health Organization is recommending a revised strategy to both conserve supply and prevent the development of resistance to the drug. First, anyone who is presumed or confirmed to have pandemic influenza, who is in serious condition or is worsening, should immediately be given oseltamivir or zanamivir. Those who are pregnant or have a high-risk medical condition should take antiviral therapy at the sign of illness with presumed pandemic influenza. Otherwise healthy adults and children (and infants) should not be automatically given antiviral therapy unless their condition deteriorates. Full details at: http://www.who.int/csr/disease/swineflu/notes/h1n1_use_antivirals_20090820/en/index.html. There was also a recent article that suggests that oseltamivir use in pediatric patients for non-pandemic influenza, while it did result in a shortening of the duration of symptoms, was not associated with a reduction in antibiotic use or in the complications of asthma, one of the most common chronic illnesses in children. See the article at http://www.bmj.com/cgi/content/abstract/339/aug10_1/b3172/?breaknews. It is not clear how each of these reports will affect the current US recommendations on the use of antiviral medication in affected patients.
OTHER ISSUES
Unfortunately, we saw that many medical facilities were very crowded this Spring as the public sought testing and reassurance in doctors offices and emergency departments. The reality is that in the U.S., the health care and public health systems are not well equipped to handle large surges in demand during a crisis. This could become much more pronounced if the severity of the pandemic strain was to worsen to the level projected in the PCAST report. Many hospitals and organizations are taking steps to help mitigate this situation, but it is unclear what effect they will have- for example New York State has mandated that most health care workers receive vaccination if they are in a patient care environment– a step intended to protect the patient but one which brings up as many questions about ethics as it does resolve issues in public health (see: http://www.nytimes.com/2009/08/19/health/policy/19swine.html?_r=2) Other interventions are being developed to stretch the medical resources that may be needed this fall, such as intensive care unit beds, but they are largely untested. Additionally, there is a great deal of uncertainty about what percentage of the health care and public health workforce will report for duty during a serious pandemic, an issue being studied by our Center.
Each of these issues merits close following as the Fall flu season begins in the next few weeks. The challenge for planners will be how best to incorporate the rapidly changing landscape of information (a very dynamic situation) into a more static strategy that most benefits the public
NCDP Commentary: Children’s Issues in the H1N1 Outbreak
By Andrew Garrett MD MPH
&
Irwin Redlener, MD, FAAP Director, NCDP
As the H1N1 outbreak progresses, it is clear that children and children’s issues need to play an important part of the discussions. Information from previous experience with influenza suggests that the youngest children (under 5 years old) may have a disproportionately high risk of complications, even more so those infants who are less than 6 months of age. For reasons that are not yet understood, 81% of the current cases in the US are in children under 18 years old (Dr. Michael Osterholm).
The “bio-psycho-social” framework is a useful tool to explore the issue of child vulnerability in any disaster, since it encourages one to consider multiple angles simultaneously. We’ll discuss some of them in the context of a possible emerging pandemic.
BIOLOGICAL: -Children may present with different types of symptoms when sick with influenza, especially the very young. Respiratory symptoms, which are typically prominent in the adult population, may be diminished in lieu of apnea, lethargy, or poor feeding. This can make deciding when to have a sick child seen by a provider challenging- but a good rule of thumb would be if a child is exhibiting any difficulties with breathing or staying hydrated, or if in the impression of the caregiver the child seems more seriously ill than with previous episodes of viral illness. When in doubt contact the child’s primary care provider or contact EMS if the child is in distress.
-In a pandemic, antiviral therapy is an important consideration for children and infants as well as adults. This has been made possible through an Emergency Use Authorization (EUA) issued by the FDA which permits the “off label” use of Tamiflu in children under 1 year old, and provides dosing recommendations, and likewise provides modified antiviral dosing recommendations for children 1-5 years old. More information on the EUA at http://www.fda.gov/bbs/topics/NEWS/2009/NEW02002.html and the dosing recommendations can be viewed on the website for the NIH at http://dailymed.nlm.nih.gov/dailymed/drugInfo.cfm?id=8790 -Tamiflu suspension is available and may be provided in some of the large caches of emergency medications, but they are difficult to store and use for a variety of logistical reasons and this may affect their availability. However, the caplet form of the medication can be used directly when released from its caplet form and sprinkled into a vehicle such as chocolate syrup, being mindful of the dosages (see above). An additional option is to make a home oral suspension. A resource for this is provided here from the Illinois Department of Health www.idph.state.il.us/pandemic_flu/TamifluFlyer_7_2008.pdf
-Children and schools are important variables in the transmission of contagious viral illness. The first cluster of patients in the US was at a school in New York City. If the spread of H1N1 continues as it has, it is likely that more school closures will be implemented. It is worth a reminder that if schools are closed to promote social distancing to slow the spread of the virus, then children should not simply be allowed to congregate in other settings. Children also need to be encouraged (required) to practice hand washing and cough etiquette just like the rest of the population.
PSYCHOLOGICAL: -Just because this is not an act of terrorism or a sudden disaster, a pandemic will be a very frightening and even traumatic experience for many children. Evidence from 9/11 and Hurricane Katrina suggests that we can take important steps now by reducing the exposure of children to frightening media reports, and by allowing children to express their feelings to an empathetic adult in an environment in which they feel as safe as possible. Remember that children who watch the TV have seen that there has unfortunately already been a child victim in this outbreak in the US. Strategies for helping children cope with fear and anxiety are available through SAMHSA at http://mentalhealth.samhsa.gov/publications/allpubs/CA-BKMARKR02/default.asp -Children may experience stress related symptoms right away or at any time later. These may commonly include depression, interpersonal problems, or regressive behavior. Caregivers should monitor children for stress-related symptoms and seek help if they are behaving abnormally.
SOCIAL: -Children in families with low income as well as children in racial or ethnic minority populations are likely at a disproportionate risk for experiencing new and multiple psychological symptoms during and after a disaster.
-Millions of children have inadequate access to primary care or are without healthcare insurance in the US, and this is worsening with the current recession. Most of these children do not have the benefit of a medical home and a source of healthcare advocacy that can give them the attention that every child deserves. This will likely compound the surge of demand for services via emergency departments as the number of cases evolves.
-Preparedness for a disaster or emergency is consistently low in the US. This is an excellent opportunity to consider your family’s personal readiness to adapt to unexpected changes in the provision of services such as healthcare, transportation, and other goods and services. Please see http://www.ncdp.mailman.columbia.edu/files/prep_model.pdf for more information, and remember to engage your children in the process of preparedness- they are counting on you to do it for them.
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