During the 20th week of 2017, the Republic of Macedonia registered 26 influenza cases/flu-like diseases ( I=1.3 /100.000). Compared with the registered cases in the last week (21), the number has increased by 23.8%. The total number of reported cases this week, exceed below the limit of very low activity, according to MEM model to determine the intensity of the activity of seasonal flu (chart 1).
Chart 1. Intensity level and weekly distribution of influenza / influenza like illness, by the expected epidemic curve of 2010-2016, the season 2015/2016 and 2016/2017
The highest number of patients was registered this week in Gostivar-(n = 10, Kumanovo-9, Tetovo-3, sveti nikole-3, Stip-1. The highest incidence of 14.6 / 100,000, was registered on the territory of Sveti Nikole, There was detected low activity of the influenza virus.
This week, the highest number of cases (n = 13) were reported in the age group of 15-64 years, and the highest incidence (I = 4,3 / 100.000) is registered among the children aged 0-4 years.
This season, from 35079 influenza cases that have been reported on the territory, there is a MB of 1695.3/100.000.
Compared to the same period last year (n = 29.094), the cumulative number of reported cases this year was increased by 20.6% and in terms of the model for the last 6 seasons (n = 25.638)was registered an increase of 36, 8%. During this season, all Public Health Centers and Regional Units have reported cases of influenza / flu-like disease.
This season, from the influenza cases that have been reported on the territory, most of them are registered in Skopje (n=4566; 13.0%), Strumica (n=3.283; 9.4%) , Gostivar n=3020, 8.6%, Kavadarci n=2998, 8,5%, Bitola n=2828, 8.1%, Prilep (n=2448; 7.0 %, Tetovo (n=2319; 6.6 %, Veles (n=2138; 6.1%) (chart 2).
The highest cumulative incidence of 6966.6/ 100,000, is registered in Kavadarciu n=2998, Sveti Nikole (I=5.913,6/100.000), Strumica (I=3.466,1/100.000), Ohrid (I=3.395,2/100.000) and Veles (I=3.226,8/100.000)(chart2,map)
During this season were registered 2 deaths associated with influenza, children aged 3 and 4 years from Kicevo and Gostivar, who were hospitalized in the Pediatric Clinic – Skopje at the Intensive Care Unit. In terms of vaccination status against seasonal influenza, the two chidren have not been vaccinated.
Chart 2. Distribution of cases and morbidity from seasonal flu by CPH / RO, season 2015/16
Picture 1. Activity level of flu by the incidence of 100,000, season 2016- 2017
Regarding the distribution of patients by age groups, the largest number of cases this season have been reported in the age group of 15-64 years –n=24217 or 69.0% and the highest incidence (2006.9 / 100,000, n=4645) is registered in the age groups 5-14 and in the age group of 0-4. (1959.7/100.000, n=2277). 3940 cases and incidence of (1503.0/ 100,000) is registered in the age group over 65. (Chart 3 and 4)
Chart 3. Distribution of cases and incidence per 100,000 from seasonal flu by age, season 2016/2017
Chart 4. Weekly distribution of seasonal flu cases by age group – incidence per 100,000 inhabitants, season 2016/2017
From the total number of cases of flu/flu-like illnesses,
- 5%.(171) in October.
- 5%(532) in November and
- in December were reported 15073 or 43.0 %,
- 17158, or 49.1% are reported in January,
- 1396 or 4.0% in February, and
- in March- 519 cases or 1.5%,
- in April- 165 cases or 0.5%,
- in May-65 cases or 0.1%. ,
or 15776 cases in 2016 and 19303 cases in 2017 (55,0%)
Chart 5. Distribution of seasonal flu by months, season 2016/2017
During the week 20 of 2017, the laboratory for virology of IPH has received 2 samples (material for laboratory diagnostics), of which 1 is Influenza B-Victoria.
During the season 2016/2017, the laboratory for virology of IPH has received 172 samples, materials for laboratory diagnostics, of which 64 (37.2%) are positive, from routine surveillance(90/40/44.4 % are positive), and 82 are from sentinel (24 or 29.3%)
62 were positive for the presence of influenza A virus (96,9%), 2 are influenza B (3.1%). From the influenza A, 60 (or 96.8%) are conformed as Influenza A/H3, аnd 2 (3,2%) are non-typed.
From the routine surveillance, n=90, 4 (44.4%) are positive to influenza, 38 are A (36 are A/H3, 2 non typed), 2 are B (1 is Influenza B Victoria lineage, 1 – Influenza B)
From the sentinels (n=82), 29.3% are positive to influenza. А/H3 (Chart 6).
Chart 6. Weekly distribution of number and percentage of positive samples of influenza 2016/2017
Table 1 presents the number of recipients per week (grouped), where 90.4% received the vaccine during the first three weeks of the commencement of the vaccination. Table 2 presents the number of recipients for weeks throughout the season 2016/2017.
Table 1. Number of vaccinated against influenza weeks, season 2016-2017
According to reports received by CPH / RO, 99.9% of total purchased vaccines 26900) are used, or.( 26670 in CPH/RO, and 230 doses from CPH Veles are given to the Special Hospital Demir Kapija. The majority of the vaccinated are aged over 64 years – 15326 cases or 57.5%, 30-64 years – 10001 cases or 37,5%, and 5-29 – 720 cases or 2.7%. In the age group 0-4 years- 10 cases, and 613 health workers (2,3%). There are no vaccinated pregnant women. From the total number of the vaccinated, 17909 persons or 67.2% have a history of chronic diseases. The vaccination has finished in every CPH/RO
Institute of Public Health does not have data to recipients in private health institutions (PHI), licensed by the Ministry of Health about the vaccination against influenza.
According to records presented in Flu News Europe (week 19/2017), the activity of influenza virus in Europe is with low activity, and the countries reported detection of 6% positive samples. The pandemic reached its peak in week 46 in the season 2009/2010, and week 48-51, in the previous 5 seasons. So far, this year, most of the viruses are subtyped as A (H3N2) with 99%, while last year, the subtype A(H1N1)pdm09 was predominant
Circulating A (H3N2) virus is antigenically similar to the class that is included in the vaccine, although two thirds of the isolated strains this season belong to a different subclass.
It is recommended that trivalent vaccines for use in the 2017-2018 northern hemisphere influenza season contain the following:
- an A/Michigan/45/2015 (H1N1)pdm09-like virus;
- an A/Hong Kong/4801/2014 (H3N2)-like virus; and
- a B/Brisbane/60/2008-like virus.
It is recommended that quadrivalent vaccines containing two influenza B viruses contain the above three viruses and a B/Phuket/3073/2013-like virus.