Re: Michigan 2011-12 Flu Season: Weeks 40-3 (Local)
Re: Michigan 2011-12 Flu Season: Weeks 40-3 (Local)
Week 3: Local
1 new hospitalization; total 7
ILI: 0.7%
During January 15-21, 26 influenza A/H3 (8SE, 1 SW, 14C and 3N) results and 1 positive influenza B (1SE) result were reported by the MDCH Bureau of Laboratories. One positive influenza B result (SW) from January 8-14 was also reported.
No deaths have been reported
In Mexico, in contrast to Canada and the USA, 90% of all laboratory-confirmed cases of influenza since late December 2011 were influenza A(H1N1)pdm09. Localized outbreaks of A(H1N1)pdm09 have also been detected in parts of the country.
In Europe, overall influenza activity remains low though respiratory disease activity and influenza virus detections have started to increase in some areas. The European Centre for Disease Prevention and Control has reported that the influenza season has begun on the continent and is currently dominated by vaccine type A(H3N2), though ILI consultations and admissions for severe acute respiratory infections (SARI) remain at inter-seasonal levels overall. Of the 44 countries reporting on the geographical distribution of influenza activity, 16 reported no activity, 21 reported sporadic activity, 4 reported local activity and 3 (Turkey, Italy and Malta) reported regional activity in recent weeks. Notable increasing trends in virus detections have been observed to be persisting over several weeks in Spain, Turkey, Sweden, Norway and Italy;
only Turkey is reporting cases numbers that are higher than at this time last season. Turkey and Malta reported medium intensity of activity and moderate impact on their health care services. All-cause mortality remains low for this time of the season. Sixteen percent of the European sentinel samples tested for influenza in the first week of 2012 were positive, a continued increase from previous weeks.
A(H3N2) was the most common virus identified in the first week of 2012. Ninety-two percent of influenza viruses detected since early October have been influenza A; of those, 93% have been A(H3N2). In the first week of 2012, all 130 subtyped influenza A samples were of the H3N2 subtype.
The northern Africa and Eastern Mediterranean regions have been reporting increasing numbers of positive influenza specimens since October, particularly in Algeria, Tunisia and the Islamic Republic of Iran. Increased virus detection is widespread but not universal. As in Europe, influenza
A(H3N2) was the predominant subtype detected, accounting for nearly all of the viruses that have been subtyped.
In northern China, both the percentage of outpatient visits that were due to ILI and the proportion of specimens testing positive for influenza increased since the last report. In contrast to other reporting regions,
influenza type B virus is the predominant type in China. The Republic of Korea and Japan have reported a persistent increase in numbers of influenza positive specimens in recent weeks, predominantly A(H3N2), and
Japan also reported increasing rates of ILI.
No notable active influenza transmission has been reported in the majority of the Caribbean and Central American countries with the exception of Costa Rica which has a decreasing trend of influenza A(H3N2) detections since transmission there peaked in late 2011.
In sub-Saharan Africa, only sporadic detections or low level transmission were reported. Transmission of influenza A(H3N2) in Cameroon appears to be decreasing after peaking in mid-December 2011, although there has been a recent increase in the detection of influenza B. Kenya has reported continuous influenza transmission for the last year; however, the number of positive specimens has been decreasing in the past 4 weeks and is now at a very low level.
Overall, activity in tropical Asia remained low. Since September, India has continued to report low level influenza B circulation.
Southern China is reporting increasing numbers of influenza B and the percentage of hospital visits for ILI has increased to 3.7%, higher than in recent weeks and higher than at the same time last year. Other countries in tropical Asia continue to report small numbers of both A(H3N2) and B.
In temperate countries of the southern hemisphere, influenza activity is at inter-seasonal levels; however, Chile, Paraguay, and Australia all report low levels persistent influenza A(H3N2). Similar out-of-season low level transmission was observed earlier in South Africa but has not persisted.
International: China, Cambodia, Egypt, Indonesia and Vietnam all report new human cases of avian influenza A/H5N1
http://www.michigan.gov/mdch/0,1607,7-132-2940_2955_22779_40563-143382--,00.html#2011-2012_MIFF
