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Page Last updated  on 23.05.2017

National Influenza Centre, Medical Research Institute

Virological surveillance (Influenza like illness - ILI from OPD patients and Severe Acute Respiratory Infection-SARI from in-ward patients) data are summarized below
  • Total number of samples= 100
  • Positivity rate of Virological surveillance is 16%
  • Influenza A (08) ,
  • Influenza B (09) were detected.       NB one sample was positive for both influenza A and B.
  • Total samples received to NIC (surveillance and clinical samples from hospitals) = 245
                    Total Positivity rate is 18% (17 % % in August 2016-Fig 01)
  • of total samples received, 53.3% were Influenza(trend is increasing)  Fig 02
  •                                             H3N2 =  20 (83.3%)
                                                HiN1 pdm 2009 = 01 ( 4.2%)           (Fig 03)
                                                    46.7 % were Influenza(trend is decreasing)
                                                                  Fig 02
  • Two deaths due to influenza A (H3N2) and  B  were reported.
There were small clusters of Infleunza A (H3N2) who have traveled to India from three hospitals in Sri Lanka,namely Chilaw (Western coast town), Balapitya and Elpitiya (both Southern towns) which grabbed media attention.


Influenza types and subtypes

  • Influenza A (13), predominant  subtype, H1N1
  • Influenza B (38) were detected. (Please see Fig 02). It is worth to note that number of positives of Influenza B are more than influenza A for this month as well.  This is similar to global trend (see below- A predominance of influenza B virus activity continued to be reported in parts of North America, in Northern Temperate Asia, South-East Asia and in parts of Euro)

  • 03 deaths were reported due to Influenza A H1N1 (in three provinces)

Figure 2


PS :Influenza B transmission, treatment with oseltamivir and prevention methods are same as influenza A type.

 Figure 3






Sub types of Influenza A in 2015

subtype of Infl A






Weekly Distribution of influenza types and sub types in srilanka 2016-2017

 Global influenza update - 285 based on data up to 05 March February, 2017 ( influenza activity continued to increase in India, the Maldives and Sri Lanka, with mainly influenza A(H1N1)pdm09 virus reported followed by influenza B virus)





Monthly summary report of National Influenza 2017



Summary 2014

summary of Year Distribution of Influenza( NIC)  in Sri Lanka during 2014  Click to download

Month 2014 Percentage of Influenza POSITIVES (A and B) 
JAN   7.07 %
FEB 11.29 %
MAR 14.88 %
APR 18.12 %
May 15 %
June 11 %
July 11   %     
Aug            03  %     all are H3N2
September 06 %    (Influenza A 5      H1 =2, H3 =2 untyped =1   Inf B 2)



  •      Weekly Influenza Viral type Activity - Week 50 National Influenza Centre , Sri Lanka

For the month of December, the predominate type was Influenza A and the subtype was H3N2. It is noteworthy to mention that Influenza A H1N1 pdm stain has emerged in the latter weeks of December.
There was an increase trend in number of samples received in December (300 when compared to 234 in November 2016) along with total number of positives.



influenza weekly





  • Weekly distrubution of Influenza 2014 uptodate Table
  • NIC Sri Lanka Virological Surveillance data 2014
  • Weekly distrubution of Influenza 2013 Table and
  • Month Click to download
    Aug Click
    Septe Click
    Octo Click
    Nov Click
    Dec Click



 Open map in new window

  jpg, 458kb

Influenza A H3N2 was the predominant strain March while influenza(2017 )



Influenza activity in the temperate zone of the northern hemisphere appeared to decrease. Influenza activity in many countries especially in East Asia and Europe already peaked. Worldwide, influenza A(H3N2) virus was predominant. In South Asia influenza activity with mainly H1N1 has been increasing. The majority of influenza viruses characterized so far were similar antigenically to the reference viruses contained in vaccines for use in the 2016-2017 northern hemisphere influenza season. Nearly all tested viruses collected recently for antiviral sensitivity were susceptible to the neuraminidase inhibitor antiviral medications.
  • In North America, overall influenza and other respiratory virus activity decreased in Canada and United States of America. Influenza activity slightly increased in Mexico with influenza A(H1N1)pdm09 virus predominating.
  • In Europe, influenza activity appeared to decrease with influenza A (H3N2) and influenza B viruses predominant in the region. Detections of influenza B virus increased in the recent weeks. Persons aged over 65 years continued to be reported as most frequently associated with severe disease from influenza infection.
  • In East Asia, influenza activity continued to decrease with influenza A(H3N2) virus predominant.
  • In Western Asia, influenza activity continued to decrease with influenza A(H3N2) and B viruses co-circulating in the region.
  • In Southern Asia, influenza activity continued to increase in India, the Maldives and Sri Lanka, with mainly influenza A(H1N1)pdm09 virus reported followed by influenza B virus.
  • In South East Asia, influenza activity remained low.
  • In Northern Africa, low influenza activity was reported in Tunisia, with influenza A(H3N2) and influenza B virus co-circulating.
  • In West Africa, influenza activity continued to be reported in Ghana and Mali, with influenza B being the main virus detected. In Eastern Africa, influenza activity was reported in Ethiopia and Mauritius with influenza A(H3N2) virus predominant.
  • In the Caribbean countries and Central America, influenza and other respiratory virus activity remained low in general.
  • In tropical South America, influenza and other respiratory virus activity remained low, although RSV activity remained elevated in Colombia.
  • In the temperate zone of the Southern Hemisphere, influenza activity was at inter-seasonal levels. National Influenza Centres (NICs) and other national influenza laboratories from 94 countries, areas or territories reported data to FluNet for the time period from 20 February 2017 to 05 March 2017 (data as of 2017-03-17 09:50:51 UTC).The WHO GISRS laboratories tested more than 156226 specimens during that time period. 34376 were positive for influenza viruses, of which 26581 (77.3%) were typed as influenza A and 7795 (22.7%) as influenza B. Of the sub-typed influenza A viruses, 651 (8.1%) were influenza A(H1N1)pdm09 and 7392 (91.9%) were influenza A(H3N2). Of the characterized B viruses, 614 (71.4%) belonged to the B-Yamagata lineage and 246 (28.6%) to the B-Victoria lineage.
  • The vaccine recommendation for the 2017-2018 northern hemisphere influenza season was made and can be consulted at this link below:


    • Report on 2nd wave of Pandemic Influenza A (H1N1) in Sri Lanka 2010

             (From 19th September to 31st December 2010)

      No of confirmed cases: 457
      No of laboratory confirmed deaths: 25



Sri Lankan Vs Global Influenza Updates 2014