Week 50 ILI activity – Source CDC FluView
# 6801
Regardless of your preferred type of celebration (Christmas, Hanukah, Kwanzaa, the Winter Solstice, Festivus . . .) the winter holiday season often finds us gathered together in relatively closed quarters to share presents, good times, and far too often . . . germs.
All of which makes this week’s FluView from the CDC, Canada’s FluWatch, and World Health Organization bi-weekly Influenza Summary of particular interest.
The early start to this year’s flu season continues across much of the United States, with A/H3N2 by far the predominate strain being reported. While it is a bit early to talk about the severity of this year’s flu season, historically H3N2 dominated seasons have typically produced more severe illness.
First stop, the CDC’s FluView Report for week 50.
2012-2013 Influenza Season Week 50 ending December 15, 2012
All data are preliminary and may change as more reports are received.
Synopsis:
During week 50 (December 9-15), influenza activity increased in the U.S.
- Viral Surveillance: Of 9,562 specimens tested and reported by U.S. World Health Organization (WHO) and National Respiratory and Enteric Virus Surveillance System (NREVSS) collaborating laboratories in week 50, 2,709 (28.3%) were positive for influenza.
- Pneumonia and Influenza Mortality: The proportion of deaths attributed to pneumonia and influenza (P&I) was below the epidemic threshold.
- Influenza-Associated Pediatric Deaths: Two influenza-associated pediatric deaths were reported. One was associated with an influenza A (H3) virus and one was associated with an influenza A virus for which the subtype was not determined.
- Outpatient Illness Surveillance: The proportion of outpatient visits for influenza-like illness (ILI) was 3.2%; above the national baseline of 2.2%. Nine of ten regions reported ILI above region-specific baseline levels. Twelve states experienced high ILI activity, New York City and 5 states experienced moderate ILI activity; 11 states experienced low ILI activity; 22 states experienced minimal ILI activity, and the District of Columbia had insufficient data.
- Geographic Spread of Influenza: Twenty-nine states reported widespread geographic influenza activity; 12 states reported regional activity; the District of Columbia and 5 states reported local activity; 3 states reported sporadic activity; Guam reported no influenza activity, and Puerto Rico, the U.S. Virgin Islands, and 1 state did not report.
A description of surveillance methods is available at: http://www.cdc.gov/flu/weekly/overview.htm
The following graphic shows just how early detection of influenza has been this year (red line), compared to previous years.
Meanwhile, Canada’s FluWatch report indicates that influenza is beginning to ramp up in several provinces as well.
- Influenza activity in Canada continued to increase in week 50; four regions reported widespread activity, and the majority of regions reported influenza circulation.
- A total of 1502 laboratory detections of influenza were reported, of which 96.7% were for influenza A viruses, predominantly A(H3N2).
- Thirty-one influenza outbreaks were reported: 24 in long-term-care facilities, 4 in hospitals and 3 in other facilities.
- Thirty-three paediatric influenza-associated hospitalizations were reported through the IMPACT network, all but one with influenza A
- Seventy-three hospitalizations with three deaths in adults ≥20 years of age were reported through Aggregate surveillance, all with influenza A.
- The ILI consultation rate increased compared to the previous week and is within the expected range for this time of year.
Virus characterization from Canada shows, like the United States, that A/H3N2 makes up the bulk of identified samples.
And globally, influenza rates in the Northern Hemisphere are beginning to rise, although many areas are lagging somewhat behind the numbers seen in North America.
This from the World Health Organization.
Influenza update
21 December 2012 - Update number 175
Summary
• Many countries in the temperate regions of the northern hemisphere are now reporting elevated detections of influenza, particularly in north America.
• Influenza activity was still low in Europe, with co-circulating of both influenza A and B viruses. However increased influenza-like illnesses were reported in more countries than previous weeks.
• There was low, but increasing influenza activity in northern Africa and the Eastern Mediterranean regions, and sporadic detections in eastern Asia.• Influenza in central America, the Caribbean and tropical south America continued to decline, with low levels of circulation of mainly influenza A(H3N2) and some influenza B viruses, except for Cuba and Peru, where influenza A(H1N1)pdm09 was predominant.
• Influenza activity in Sub-Saharan Africa declined to low levels, with mainly influenza B, except in Ghana, where influenza A(H1N1)pdm09 was reported.
• Influenza in most South East Asian countries was declining, except in Sri Lanka and Viet Nam.
• Influenza activity in the temperate countries of the southern hemisphere continued at inter-seasonal levels.
The CDC recommends a flu shot for just about everyone each year, but regardless of whether you received one, this Holiday season is a good time to hone your basic flu hygiene skills.
The CDC recommends:
Take everyday preventive actions to stop the spread of germs.
- 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. If soap and water are not available, use an alcohol-based hand rub.*
- Avoid touching your eyes, nose and mouth. Germs spread this way.
- Try to avoid close contact with sick people.
- If you are sick with flu–like illness, CDC recommends that you stay home for at least 24 hours after your fever is gone except to get medical care or for other necessities. (Your fever should be gone without the use of a fever-reducing medicine.)
- While sick, limit contact with others as much as possible to keep from infecting them.
As an added bonus, these healthy hygiene habits can also help protect you against the other winter time scourge, Norovirus – which, like influenza, can wreck a family holiday gathering in record time.
