Hospitalized H1N1 New Yorkers Had Underlying Risk Factors
Illness from H1N1 influenza continues to occur throughout New York City, with most people experiencing only mild illness. Emergency room visits have declined somewhat after spiking dramatically during the third week of May. As anticipated, however, the infections have caused hospitalizations and deaths.
More than 300 New Yorkers have been hospitalized with H1N1 flu since late April, and the Health Department today provided the first detailed breakdown of risk factors among those hospitalized. A preliminary analysis of 152 hospitalized patients shows that at least 82% have belonged to one or more groups at higher risk of severe illness or complications from influenza. Those at higher risk of flu complications include:
* People who are over 65, under age 2, or pregnant
* People with chronic lung problems, such as asthma or emphysema
* People with chronic heart, kidney, liver or blood disorders
* People with neurological disorders that can cause breathing problems
* People with diabetes
* People whose immune systems are weakened due to illness or medication
* People under 18 years who are on long-term aspirin therapy
So far, the most common risk factor in New York City has been asthma – an underlying risk factor among 41% of the New Yorkers hospitalized for H1N1 flu. Other important risk factors include being less than 2 years of age (18% of hospitalized patients), having a compromised immune system (13%), having heart disease (12%), or being pregnant. The Health Department recommends that people with asthma, or any of the other conditions listed here, to call a doctor right away if they develop flu-like illness. Antiviral medicines such as Tamiflu® or Relenza®, if taken early (within the first two days of symptoms), can help reduce the risk of severe illness and complications. A diagnosis of flu-like illness does not require medical testing. Anyone feeling ill can take his or her temperature with a home thermometer. A temperature of 100.4 degrees is a fever. If the fever is accompanied by cough or sore throat, the condition qualifies as flu-like illness.
The Health Department is continuing a more detailed analysis of hospitalized patients’ health histories, which may identify other underlying health conditions. The agency will report these findings when the analysis is complete.
Additional H1N1-related deaths identified
The Health Department today linked two more deaths to H1N1 influenza. The latest fatalities – both in adults in their early and mid 40s – bring the total number of deaths to seven. All deaths to date have occurred in people under 65 years of age (the median age is 43). Six of the seven deaths have occurred in people with underlying conditions (including obesity) that can interfere with normal breathing, and one death is still under investigation. To safeguard patient privacy, the Health Department does not report on the clinical details of individual cases.
Other Health Department H1N1 monitoring activities
The City’s syndromic surveillance system shows that flu-related emergency department visits declined last week from their peak on May 25. Flu-related visits, which can reflect factors other than actual illness, were 15 times the expected level for this time of year. The number has since declined but is still far higher than the usual level.
Hospitals report that many of the patients seeking care at emergency rooms have been mildly ill or “worried but well.” Others have reportedly come seeking tests for H1N1 infection, or seeking notes certifying that they are free of H1N1 infection when returning to work or school after an illness. The Health Department urges people not to go to the emergency department for these reasons. Anyone with flu-like illness should stay home until fully recovered and free of symptoms for 24 hours. H1N1 testing is not widely available – or necessary – for people with mild flu-like illness. Testing is not available or needed before returning to work or school. For more information see H1N1 ‘Swine Flu’ What You Need to Know (Basic FAQ) (PDF).
People in the risk groups mentioned above should call their doctor or clinic if they develop symptoms, but only people with severe symptoms, such as difficulty breathing, should visit emergency departments.
The Health Department continues to survey New Yorkers to better understand what proportion of the city’s population has experienced flu-like illness since late April, and what types of symptoms people have experienced. The agency recently completed a random-digit-dial telephone survey of 1,000 New York City residents and will soon conduct a voluntary online survey of several thousand New York City employees. Results from both surveys will be made public when the analysis is complete.