Anaesthesiology Intensive Therapy, 2010,XLII,1; 38-42

Pandemic influenza A/H1N1v – guidelines for infection control from the perspective of Polish ITUs

*Robert Becler, Paweł Andruszkiewicz, Andrzej Kański

2nd Department of Anaesthesiology and Intensive Therapy, Warsaw Medical University

  • Fig. 1. Preparation of a mask
  • Fig. 2. Placement of a mask
  • Fig. 3. Sealing of a mask around the nose
  • Fig. 4. Fit testing. A mask covered with the hand should sink in slightly during inspiration and be tight around the edges during expiration

In some countries, the influenza A/H1N1v pandemic, recently announced by WHO, was severe. Up to 10-30% of patients required ITU therapy due to rapidly increasing respiratory failure. In Poland, recommendations concerning the management of A/H1N1v infections, including those during ITU hospitalization, are vague and scattered. The WHO guidelines stress that the spread of infections should be limited by observance of personal hygiene rules, use of appropriate preventive measures and suitable administrative and technical actions.

Only 30-60% of medical staff cleans their hands. Hand washing practices are inaccurate and too rare. Likewise, protective clothes and face masks are worn too rarely.  FFP3 is believed to be the best mask in such cases, if properly used. Such masks should be individually adjusted, placed tightly over the face, without leaks around the edges. After use, masks and protective clothes should be considered as medical waste.

Moreover, the guidelines for management of ITU patients diagnosed with A/H1N1v infections are extremely relevant in cases of other infections.

The A/H1N1 virus was first reported in North America in March 2009; since there was no residual resistance, the virus spread quickly beyond the continent and made WHO announce the pandemic alert. The pandemic influenza virus, which is a hybrid of human and animal viruses, multiplies in the airway epithelial cells. It does not induce viraemia. The general manifestations result from the action of inflammatory cytokines. The virus reservoirs are humans, pigs, domestic and wild birds. The infection is spread by droplets, direct contact with infected individuals and with contaminated surfaces. In the majority of cases, the infection is mild, without complications and resolves spontaneously; however, infection-related severe complications and deaths have also been described. The 2009 pandemic influenza differs from the seasonal one as its severe course requiring hospitalization affects 80% of children and adults aged 24-64 years and not those above the age of 65, as is the case in seasonal influenza. The A/H1N1 virus attacks the upper (as in seasonal influenza) and lower airways. Therefore, in some countries up to 10-30% of the infected patients required ITU treatment due to rapidly progressing respiratory failure leading to therapy-resistant hypoxaemia [1, 2].

In Poland, the first case of A/H1N1v influenza was noted on May 7th 2009. The National Institute of Public Health (NIPH) in its report of December 30th 2009 informed about 2301 documented cases of pandemic influenza and 135 infection-related deaths in Poland [3]. According to the Central Statistical Office and NIPH, the number of influenza-related deaths in November 2009 equalled the number in the entire 2007 and outnumbered that in 2008; yet it is anticipated that the mean mortality rates in the years 2009/2010 should not be higher than those for seasonal influenza [4, 5].

There is a risk of higher virulence of A/H1N1v associated with its rapid mutations. Therefore, the information regarding interspecies transmission of infections are alarming; such infections favour the exchange of RNA genome segments with animal viruses, which may lead to the “antigenic shift” resulting in the emergence of highly virulent viruses [5].  Despite optimistic estimates of December 2009 about a rapid decrease in the incidence of pandemic influenza, predictions for 2010 are not clear. The dying out A/H1N1v pandemic should be considered a warning and a test of preparations (administrative, technical, educational, etc.) before the next wave of cases and an attack of a new, unknown virus in the future. Proper preparations to limit the droplet- or aerosol-borne infections and appropriate use of personal protective measures may be invaluable in the context of potential threats of terrorist attacks with biological weapons.

According to the European Centre for Disease Control and Prevention estimates, 1/1000 European citizens will be hospitalized due to pandemic influenza in 2009-2010, including 25% in ITUs. Based on these rates, it could be assumed that in Poland more than 9000 patients with respiratory failure would be hospitalized in ITUs [1]. In our 476 ITUs ( in 1st and 2nd care hospitals) with 2480 beds for adults and 155 for children, about 75% of beds are constantly occupied [6]. The disproportion between capacities and needs is apparent. A low number of paediatric ITU beds is particularly alarming as the risk of severe influenza in the group of small children (<2 years of age) is extremely high.

The effectiveness of pandemic influenza control depends on several factors: availability of vaccines, virulence of the virus, financial capacities and organizational efficiency of health care in a given country.  It is assumed that in the initial phase of pandemic with low incidence rates, patients are isolated in infectious diseases hospitals; simultaneously actions are undertaken to produce a specific vaccine. Once produced, protective vaccination, being the most effective method to reduce the incidence, is started.  Despite clear recommendations of WHO [7], in 2009, in Poland the decision about vaccinations was not made, even in high risk groups where infections are likely to be associated with severe complications, e.g. pregnant women (ten times higher risk of ITU hospitalization) or medical professionals, whose infections are highly likely due to direct contact with infected patients [7, 8].  Mass infections amongst health care workers may lead to destabilization of the system due to absences and uncontrolled spread of infections.

Recommendations concerning the control of A/H1N1v infections in Polish health institutions, including ITUs, are extremely general, incomplete and scattered [9]. The websites of the Ministry of Health, National Institute of Hygiene (NIH) and the Chief Sanitary Inspector lack suitable guidelines. Therefore, for designing the ITU management strategies the information featured on websites of the World Health Organization (WHO), National Health Service (NHS), European Centre for Disease Prevention and Control (ECDC), Centers for Disease Control and Prevention (CDC), and Occupational Safety and Health Administration (OSHA) could be used  [10, 11, 12, 13, 14].

On December 16, 2009, WHO published the document containing the guidelines for actions to limit the spread of A/H1N1v infections, which include hygiene-related rules to follow, administrative and technical preparations and use of personal protective measures [15]. Meticulous observance of hygiene rules and isolation of the affected patients are the key preventive actions enabling to limit the risk of transmission of infections from the patient to medical personnel or other patients.  The problem is topical as the Polish studies performed in 2009 showed that the medical staff significantly infringed hygiene-related patterns. The authors state that only 30-60% of the personnel remember about hand washing [16]. Hands are washed too rarely and carelessly. Negative hygienic patterns are strengthened and become routine behaviour. During medical procedures, the personnel wear rings, watches, clothes with long sleeves. Additional protective clothes, masks and caps are worn too rarely and the way of putting them on and removing is improper.

According to the WHO experts, organizational-administrative strategies are decisive for effective control of infection spread. They include the “road map” for actions to prevent, detect and control the influenza during the therapeutic process starting from the moment of first contact of the infected patient with the hospital. The relevance of trainings for medical staff is highlighted. In Poland, the key role in administrative actions during influenza pandemic should be in the hands of Hospital Infection Control Teams, which are obligated to prepare and update the programmes of prevention and elimination of hospital infections [17].

The recent literature data concerning the use of protective and filtrating masks are conflicting; therefore, optimal recommendations are difficult to put forward.  It is assumed that surgical masks successfully protect the airways against penetration of viruses, which escaped from the patient`s organism with large droplets of the respiratory secretion, blood or other body fluids. However, controlled clinical studies regarding this issue are lacking [18]. When the virus-infected secretions form the aerosol, FFP/ N95 masks should be used [15] – e.g. during endotracheal intubation, airway suction in the open system, resuscitation, bronchoscopy. There are no explicit recommendations regarding airway protection of the personnel during nebulization or non-invasive lung ventilation in patients infected with A/H1N1 virus.

In December 2009, the results of the prospective, randomized clinical study evaluating the efficacy of two types of masks protecting against influenza infections in the hospital setting were published. The study was carried out amongst 478 nurses who used surgical or N95 masks while taking care of patients with seasonal influenza. It was demonstrated that the incidence of serologically confirmed influenza infections was similar in both groups, which proves that surgical masks were not less effective than N95 masks. The authors make it clear that the study was conducted in the routine hospital care setting while under conditions of increased risk of infections - strong contamination with aerosol containing influenza viruses- the use of N95 masks is well-grounded [19].

Different results were obtained in the study involving 1936 medical professionals of Beijing hospitals, who are inclined to wear protective masks continuously. The aim of the study was to compare surgical and N95 masks as to their effectiveness to protect against influenza infections. The findings showed that surgical masks were completely ineffective; N95 masks protected 60% of workers [20].

Since there are no Polish recommendations concerning the use of preventive masks in the current influenza pandemic, the guidelines prepared by the Central Institute of Labour Protection – National Research Institute (CILP-NRI) should be considered binding. The guidelines recommend the use of filtrating FFP3 masks when there is a risk of inhalation of aerosol infected with A/H1N1 virus ( in accordance with the norm PN-EN 149:2004). Such guidelines are in agreement with the directive of the Minister of Health of April 22nd 2005 on biological factors harmful for health at work and protection of workers professionally exposed to those factors [21], which enables to categorize the pandemic influenza virus of 2009/2010 into risk category 3, requiring the use of FFP3 masks. 

FFP3 masks are characterized by extremely high effectiveness of filtration and smaller leaks between the edges and face (the higher the class of protection, the smaller the leak). CILP-NRI underlies the necessity for individual mask-face adjustments according to the directive of the Minister of Labour and Social Policy of September 26th 1997 on general health and safety regulations [22]. Proper adjustments limit the risk of infection decreasing the leak of unfiltered air to the airways. On our market, the models of filtrating masks are available in one, universal size yet their design and shape differ markedly. Therefore, to achieve full protection, individual adjustments of a particular model to the face are necessary. In some cases, two or three attempts are needed to provide the satisfactory tightness. In Poland, the procedure of fit test is supervised by the special unit of CILP-NRI. Thanks to obligatory trainings, the employer should learn the rules of proper mask usage and know how to perform the sealing test (Fig. 1-4). Masks should not be used by individuals with facial hair or facial scars (e.g. burns) as in such cases tightness of the mask is hampered.

Another important element reducing the risk of influenza virus spread is the knowledge of proper use of the remaining measures of personal protection, including the proper order of removing the protective clothes. Before leaving the isolation room, the protective clothes should be taken off in the following order: gloves, a gown, goggles or a face shield; the clothes removed are considered medical waste (or decontaminated if reusable). The last element to be removed after leaving the patient`s room is the protective mask, which should be immediately followed by hand washing [23].

In ITUs, the rules of protection against infections should be followed even when the pandemic is over and should apply not only to the medical personnel but also to patients and visitors. The existing guidelines should be referred to [24] and adapted to current knowledge and recommendations of international organizations.



1.    Gajewski P, Mrukowicz J:  Grypa - epidemiologia, rozpoznanie, leczenie, profilaktyka. Medycyna Praktyczna on-line

2.    Mrukowicz J: Czym się różni budowa wirusa grypy pandemicznej A/H1N1v od klasycznych wirusów grypy sezonowej? Medycyna Praktyczna on-line

3.    NIZP: Wirus grypy A(H1N1)v – aktualne raporty światowe,

4.    Szymborski J: Opinia w sprawie sytuacji epidemiologicznej grypy A/H1N1 w Polsce. Medycyna Praktyczna on-line 

5.    Wywiad Redakcji z dr med. Pawłem Grzesiowskim.  Medycyna Praktyczna on-line

6.    Paulo M, Kaczmarczyk A: Gdzie szukać respiratorów? Medycyna Praktyczna on-line   

7.    WHO Strategic Advisory Group of Experts on Immunization – report of the extraordinary meeting on the influenza A (H1N1) 2009 pandemic, on-line

8.    WHO: Clinical management of human infection with pandemic influenza (H1N1) 2009: revised guidance, on-line

9.    Kuchar E: Czy są w Polsce jakieś zalecenia dotyczące metod profilaktyki zakażenia A/H1N1v personelu medycznego od pacjenta w ciężkim stanie (oczywiście poza podstawowymi zasadami higieny)? Medycyna Praktyczna on-line

10.    WHO: Pandemic (H1N1) 2009, on-line 

11.    NHS: Important information about swine flu, on-line

12.    ECDC: 2009 influenza A9H1N1 pandemic, on-line

13.    CDC:  H1N1 flu, on-line

14.    OSHA:  Safety and health topics pandemic influenza, on-line

15.    WHO: Updated guidance 16 December 2009: infection prevention and control during care for confirmed, probable, or suspected cases of pandemic (H1N1) 2009 virus infection and influenza – like illnesses, on-line  

16.    Garus A, Szatko F: Przestrzeganie wzorców zachowań higienicznych przez personel medyczny w szpitalach.  Probl Hig Epidemiol 2006; 87: 176-181.

17.    Ustawa z dnia 5 grudnia 2008 o zapobieganiu oraz zwalczaniu zakażeń i chorób zakaźnych u ludzi.   Dz. U. Nr 234 poz. 1570, art. 14 i art. 15.

18.    Jefferson T, Del Mar C, Dooley L, Ferroni E, Al-Ansary A, Bawazeer GA, van Driel ML, Foxlee R, Rivetti A: Physical interventions to interrupt or reduce the spread of respiratory viruses: systematic review.  BMJ 2009; 339: b3675.

19.    Loeb M, Dafoe N, Mahony J, John M, Sarabia A, Glavin V, Webby R, Smieja M, Earn DJD, Chong S, Webb A, Walter SD: Surgical mask vs N95 respirator for preventing influenza among health care workers: a randomized  trial.  JAMA  2009; 302: 1865-1871.

20.    Macintyre C, Wang Q, Cauchemez S, Seale H, Dwyer D, Peng Y, Weixian S, Ferguson N Refguson M: The first randomized, controlled clinical trial of surgical masks compared to fit-tested and non-fit tested N95 masks in the prevention of respiratory virus infection in hospital health care workers in Beijing, China. Interscience Conference on Antimicrobials and Chemotherapy, 

21.    Rozporządzenie Ministra Zdrowia z dnia 22 kwietnia 2005 r. w sprawie szkodliwych czynników biologicznych dla zdrowia w środowisku pracy oraz ochrony zdrowia pracowników zawodowo narażonych  na te czynniki. Dz. U. 2005 nr 81 poz.716.

22.    Obwieszczenie Ministra Gospodarki, Pracy i Polityki Społecznej z dnia 28 sierpnia 2003 r. w sprawie ogłoszenia jednolitego tekstu rozporządzenia  Ministra Pracy i Polityki Socjalnej w sprawie ogólnych przepisów bezpieczeństwa  i higieny pracy. Dz. U. Nr 169, poz 1650 z późn. zm.

23.    Department of Health and the Health Protection Agency  NHS.  Pandemic influenza: guidance for infection control in critical care,

24.    Fleischer M: Izolacja – materiały szkoleniowe dla pielęgniarek epidemiologicznych, zeszyt III; Polskie Stowarzyszenie Pielęgniarek Epidemiologicznych, Wrocław 2005.



*Robert Becler

II Klinika Anestezjologii
i Intensywnej Terapii
Warszawskiego Uniwersytetu Medycznego
ul. Banacha 1A, 02-097 Warszawa
tel.: 0-22 599 20 32

Received: 15.12.2009
Accepted: 06.01.2010