Background
On 11 June 2009, WHO raised its pandemic alert level from phase 5 to phase 6 and characterized the outbreak of pandemic (H1N1) 2009 as moderate. Since the first recorded cases in April 2009, the virus has spread rapidly across the globe resulting in sustained community transmission in numerous countries and at least two WHO regions.
Health-care facilities (HCF) face the challenge of providing care for patients infected with the pandemic (H1N1) 2009 virus. It is critical that health-care workers (HCW), patients, and visitors follow the appropriate infection control (IC) precautions in order to minimize the possibility of transmission associated with health care.
IC measures for pandemic (H1N1) 2009 should be in harmony with other IC measures and strategies in health care. It is particularly important to acknowledge and quickly identify other respiratory diseases that may require different IC measures (e.g. pulmonary tuberculosis) and that have the potential for being overlooked due to large numbers of patients with respiratory symptoms.
Human-to-human transmission of the pandemic (H1N1) 2009 virus appears to be primarily through droplets. Therefore, IC precautions for patients with suspected or confirmed pandemic (H1N1) 2009 virus infection, as well as those with influenza-like symptoms or illnesses, should ensure control of the spread of respiratory droplets. The document “Infection prevention and control of epidemic- and pandemic-prone acute respiratory diseases in health care - WHO Interim Guidelines”1 provides detailed information on infection prevention and control precautions for influenza virus with sustained human-to-human transmission applicable for the current pandemic (H1N1) 2009. This guidance note summarizes and highlights the main issues contained in the aforementioned document.
This document has been developed to meet the urgent need for guidance and the recommendations are only valid until new guidance becomes available, at the latest until the end of 2009.
Fundamentals of infection prevention strategies
Administrative controls are key components in infection prevention strategies and include implementation and facilitation of IC precautions; patient triage for early detection, patient placement and reporting; organization of services; policies on rational use of available supplies; policies on patient procedures; and strengthening of IC infrastructure.
Environmental/engineering controls, such as basic HCF infrastructure,2 adequate environmental ventilation, proper patient placement and adequate environmental cleaning can help reduce the spread of some pathogens during health care.
Rational use of available personal protective equipment (PPE) and appropriate hand hygiene also help reduce spread of infection.
1 Infection prevention and control of epidemic- and pandemic-prone acute respiratory diseases in health care WHO Interim Guidelines. WHO, 2007. Available at http://www.who.int/csr/resources/publications/WHO_CD_EPR_2007_6/en/index.html.
2 Essential environmental health standards in health care. WHO, 2008. Available at http://whqlibdoc.who.int/publications/2008/9789241547239_eng.pdf.
3 WHO Guidelines on Hand Hygiene in Health Care. WHO 2009. Available at http://whqlibdoc.who.int/publications/2009/9789241597906_eng.pdf.
4 Standard Precautions: Basic precautions designed to minimize direct, unprotected exposure to potentially infected blood, body fluids or secretions applicable to all patients. Available at www.who.int/csr/resources/publications/standardprecautions/en/index.html.
5 PPE for Droplet Precautions: Health-care workers to wear medical mask if working within approximately 1 meter of the patient.
6 Groups at high risk: Infants and young children <5>65 years), nursing home residents, pregnant women, and patients with co-morbid conditions such as cardiovascular, respiratory or liver disease, diabetes, and those with immunosuppression related to malignancy, HIV infection or other diseases.
7 Details on the correct use of PPE are available at: http://www.who.int/csr/resources/publications/WHO_CD_EPR_2007_6/en/index.html
Critical infection control measures
Several measures are recommended in the context of pandemic (H1N1) 2009 and other epidemics. First, avoid crowding patients together (maintain a minimum distance of >1 metre between patients). Second, promote respiratory etiquette and hand hygiene by providing necessary supplies and training individuals in the proper use of medical masks and hand hygiene immediately after contact with respiratory secretions. Third, apply Standard4 and Droplet5 Precautions. Last, consider special arrangements for vulnerable groups at high risk6 for complications from pandemic (H1N1) 2009 viral infection.
Summary of infection control precautions in specific situations
1. Caring for patients with suspected or confirmed infection
For staff providing care for patients with suspected or confirmed pandemic (H1N1) 2009 infection and for patients with influenza-like symptoms, the following precautions should be taken.
1.1 When working in direct contact with patients, Standard and Droplet Precautions should always be applied.
As per Droplet Precautions:
• wear a medical mask, if working within or <>12 air changes per hour);
• avoid permitting unnecessary individuals into the room; and
• perform hand hygiene before and after patient contact, and after PPE removal.
8WHO Information for Laboratory Diagnosis of New Influenza A (H1N1)Virus in Humans. WHO, 2009. Available at http://www.who.int/csr/resources/publications/swineflu/diagnostic_recommendations/en/index.html.
Aspiration of the respiratory track may be associated with increased risk for disease transmission. Nasopharyngeal swabbing and the vigorous swabbing of tonsils for sample collection may trigger intense cough at very close distance to the person doing the procedure.
Clinical management of human infection with avian influenza A (H5N1) virus. WHO, 2007. Available at http://www.who.int/csr/disease/avian_influenza/guidelines/clinicalmanage07/en/index.html
PPE for Contact Precautions: Health-care workers should wear gowns and clean gloves when providing direct care.
IC recommendations for avian influenza in health-care facilities is available at: http://www.who.int/csr/disease/avian_influenza/guidelines/aidememoireinfcont/en/index.html .
2. Collection of laboratory specimens
Upper respiratory tract specimens are the most appropriate samples for laboratory testing of pandemic (H1N1) 2009 virus in humans. Samples should be taken from the deep nostrils (nasal swab), nasopharynx (nasopharyngeal swab), nasopharyngeal aspirate, and/or throat or bronchial aspirate. Blood samples may be used for serologic purposes (either during the acute or convalescent phases). In addition to Standard Precautions, specific IC precautions should be taken when collecting patient specimens as follows.
2.1 Nasal swab and nasal wash:
• use face protection (either a medical mask and eye-visor or goggles, or a face shield);
• wear a gown and clean gloves; and
• perform hand hygiene before and after patient contact, and immediately after removal of PPE.
2.2 Collection of nasopharyngeal aspirate, nasopharyngeal swab, throat swab or bronchial aspirate:
• follow the same precautions as for Aerosol generating procedures (above).
2.3 For the collection of blood:
• use a medical mask (if performed during the acute infectious phase);
• use clean gloves;
• perform hand hygiene before and after patient contact, and immediately after removal of PPE.
3. Infection control precautions for patient care in regions where both avian influenza A (H5N1) and pandemic (H1N1) 2009 have been reported Patients presenting with influenza-like illness (ILI) might be infected with different types of influenza virus (e.g. avian influenza A (H5N1) or pandemic (H1N1) 2009), as well as other respiratory pathogens. Epidemiological and clinical10 clues should be used in triage areas to identify and apply the appropriate infection prevention and control measures in accordance with the most likely diagnosis. Laboratory diagnosis should be pursued for etiological clarification. A laboratory confirmed diagnosis is not always available or might be delayed, but clinical clues and epidemiological link(s), such as contact with infected patients or animal exposures, can aid in the presumptive diagnosis of avian influenza A (H5N1) and pandemic (H1N1) 2009. For laboratory confirmed or suspect cases of avian influenza A (H5N1) infection, Standard plus Droplet plus ontact11 Precautions and eye protection should be applied when providing routine care.
