Epidemiologists in Bulgaria Predict a Severe Flu Season

Health | November 25, 2021, Thursday // 16:08|  views


1. What flu strains will attack us this year?

It is assumed that in the 2021/2022 season, influenza viruses will be circulating, which are similar to the viruses included in the influenza vaccines recommended by the WHO for the countries of the Northern Hemisphere, namely:

∙ A / Victoria / 2570/2019 (H1N1) pdm09;

∙ A / Cambodia / e0826360 / 2020 (H3N2);

∙ B / Washington / 02/2019 (B / Victoria lineage);

∙ B / Phuket / 3073/2013 (B / Yamagata lineage).

It is not yet possible to predict which of these viruses will dominate.


2. To what extent does the flu vaccine protect us?

The effectiveness of influenza vaccines is not 100%, but they provide protection against severe forms of influenza and complications, especially in high-risk individuals. According to scientific publications, with influenza vaccines:

∙ The outpatient examinations due to influenza in the general population are reduced by 50-60%.

∙ Influenza hospitalizations for people over 50 is decreased by 57%.

∙ There is a reduction of the number of children admitted to intensive care units by 74%.

∙ Reduction is observed by 52% and 79% hospitalizations in people with chronic lung disease and diabetes, respectively.

The effectiveness of influenza vaccines depends on the age and immune status of the vaccinated person, but mostly on the antigenic proximity between vaccine and epidemic influenza viruses. Vaccines have the highest efficacy against influenza B viruses, as they are the most genetically stable, and the lowest against influenza A (H3N2) viruses, which are the most variable. So it is important for the effectiveness of vaccines which influenza virus predominates during a given epidemic season.


3. Is it too late if we now decide to get a flu vaccine?

It is recommended that the flu vaccine be given at least 14-21 days before the start of the circulation of influenza viruses in the country in order to have time to develop immunity. No circulation of influenza viruses has been detected so far, so an influenza vaccine can be given. It is believed that even at a time when influenza viruses are circulating in the country, a vaccine can be given, provided the person is healthy and has no acute illness.


4. For which groups of the population is the flu vaccine recommended?

Influenza vaccines are recommended for people who are at increased risk of severe flu and complications. According to the WHO, annual influenza vaccination is recommended for people with:

High risk of complications:

∙ Pregnant women (high priority);

∙ Children aged 6 months. up to 5 years;

∙ Adults ≥ 65 years;

∙ Persons over 6 months of age with chronic diseases (diabetes, chronic heart and lung diseases, congenital or acquired immune suppression, HIV / AIDS, etc.);

Increased risk of infection or transmission:

∙ Medical staff.

According to ORDINANCE № 15 of 12.05.2005 on immunizations in the Republic of Bulgaria (SG, issue 45 of 31.05.2005, Supplemented - SG, issue 77 of 2012, in force from 9.10.2012) Annual influenza vaccination is recommended for the following groups of people:

All persons over 65 years of age.

All adults and children over 6 months of age suffering from the following diseases:

· Chronic lung diseases, incl. asthma;

· Chronic diseases of the cardiovascular system;

· Metabolic diseases, especially diabetes;

· Chronic renal failure and hemodialysis patients;

· Congenital and acquired immunosuppression, including medication; HIV carriers and patients with clinically manifested HIV infection;

· Hemoglobinopathies;

· Organ transplantation.

Persons living in organized groups (homes for medical and social care, military units, dormitories, etc.);

Persons at increased risk of infection in connection with their profession (transport workers, army and police officers, medical staff, etc.);

All who are in contact with people at increased risk of complications (family members, including children; staff of medical, health and social institutions).


5. What should we say to people who are hesitant to get vaccinated against the flu?

During the COVID-19 pandemic, recommendations for influenza vaccination are particularly important because of the likelihood of contracting SARS CoV-2 and influenza virus, which would aggravate the patient's condition. This is particularly important for people at increased risk of severe COVID-19 and influenza (people ≥ 65 years of age, people with chronic illnesses and weakened immunity). Priority groups for influenza vaccination should also be medical workers, as well as residents and staff of social institutions.


6. When is the flu wave expected this year?

In Bulgaria, the circulation of influenza viruses usually begins in December, with the influenza epidemic unfolding in January-February.


7. Can we expect a weaker flu wave this year as well?

In the past season 2020/2021, the circulation of influenza viruses in the European Union was unusually weak, and in Bulgaria for the first year no influenza viruses were detected. This is explained by the applied anti-epidemic measures, which have an effect not only on the pandemic coronavirus, but also on influenza viruses. If the anti-epidemic measures are strictly observed this season as well, it is possible that there will not be a severe flu epidemic, as was observed in the seasons before the pandemic. However, early detection of influenza A (H3N2) virus in Europe suggests that the current flu season may be more severe than the previous one, especially for the elderly and immunocompromised.

/Press Center Ministry of Health

We need your support so Novinite.com can keep delivering news and information about Bulgaria! Thank you!

Tags: flu, influenza, virus, Bulgaria


» Related Articles: