Influenza monthly update, May 2018

7 June 2018 – In the WHO Eastern Mediterranean Region, influenza activity continue to decrease in the month of May in many countries reporting data to FluNet and EMFLU namely, Afghanistan, Bahrain, Egypt, Iran (Islamic Republic of), Iraq, Jordan, Kuwait, Lebanon, Morocco, occupied Palestinian territory, Oman, Pakistan, Qatar, Saudi Arabia, and Tunisia (Fig. 1).

Fig. 1. Influenza geographic spread  in Eastern Mediterranean Region, May 2018

Fig. 1. Influenza geographic spread  in Eastern Mediterranean Region, May 2018

Influenza activity by subtype

  • In May 2018, no new cases of human influenza A(H5N1) were reported in Egypt.
  • In the northern Africa influenza transmission zone, Tunisia reported sporadic circulation of A(H1N1)pdm09 and influenza B, while Egypt reported co-circulation of all seasonal influenza viruses.
  • In the Western Asia influenza transmission zone, influenza A(H1N1)pdm09 was detected with influenza B virus in Bahrain, Kuwait, Lebanon, Oman, Qatar and Saudi Arabia. Jordan reported influenza A(H1N1)pdm09 and influenza B, while Iraq reported circulation of influenza A(H1N1)pdm09, and oPt reported circulation of influenza A(H1N1)pdm09 and influenza A(H3N2). 
  • In southern Asia transmission zone, Afghanistan reported sporadic circulation of influenza B; Iran (Islamic Republic of) reported sporadic detection of seasonal influenza A, and Pakistan reported co-circulation of all seasonal influenza viruses.

Source of transmission zones

Fig. 2 shows the weekly distribution of influenza subtypes.

Fig_2

Fig. 2. Weekly positive cases of influenza by subtype, Epi week 21/2017–2018

Source: FluNet and EMFLU

Circulating influenza viruses by subtype 

  • During May 2018, national influenza centres and influenza laboratories in the Region tested a total of 3901 specimens for influenza viruses of which 366 tested positive (9%).
  • The average percentage of positivity rates is 9%, with highest positivity rate recorded in Bahrain and Pakistan.
  • Of the viruses tested; 245 (67%) were influenza A viruses, including 184 (50%) influenza A(H1N1)pdm09 virus and 47 (13%) were influenza A(H3) virus. Influenza B virus accounted for 121 (33%) including 93 (25%) influenza B (lineage not determined) and 25 (7%) B (Yamagata lineage) (Fig. 3).

Fig_3

Fig. 3. Circulating influenza viruses in the Region by subtype, Epi week 18-21, 2018

Related link

Influenza monthly update, May 2018