Swine
influenza
Updated 2009 Apr 28 04:50 PM: reported cases of swine influenza A (H1N1)
in humans in 2009 (WHO Press Briefing 2009 Apr 28)
update
General
Information (including ICD-9/-10 Codes)
· respiratory disease of pigs caused by influenza type A virus, usually does not infect humans(1)
· Director-General of WHO has declared "Public Health Emergency of International Concern" regarding outbreak in 2009 (WHO Disease Outbreak News 2009 Apr 26)
· swine flu
· 487.0 influenza with pneumonia
· 487.1 influenza with other respiratory manifestations
· 487.8 influenza with other manifestations
· J10 influenza due to other identified influenza virus
o J10.0 influenza with pneumonia, other influenza virus identified
o J10.1 influenza with other respiratory manifestations, other influenza virus identified
o J10.8 influenza with other manifestations, other influenza virus identified
· J11 influenza, virus not identified
o J11.0 influenza with pneumonia, virus not identified
o J11.1 influenza with other respiratory manifestations, virus not identified
o J11.8 influenza with other manifestations, virus not identified
· additional codes for complications
o G05.1 encephalitis, myelitis and encephalomyelitis in viral diseases classified elsewhere
o H67.1 otitis media in viral diseases classified elsewhere
o I41.1 myocarditis in viral diseases classified elsewhere
· CDC definitions(2)
o confirmed case - person with acute respiratory illness with swine influenza A (H1N1) virus infection laboratory confirmed at CDC by e 1 of
§ real-time reverse transcriptase polymerase chain reaction (RT-PCR)
§ viral culture
o probable case - person with acute febrile respiratory illness who is
§ positive for influenza A, but negative for H1 and H3 by influenza RT-PCR
§ positive for influenza A by influenza rapid test or influenza immunofluorescence assay (IFA) plus meets criteria for suspected case
o suspected case - person with acute respiratory illness (defined as recent onset of e 2 of rhinorrhea or nasal congestion, sore throat, or cough) plus either of
§ close contact to confirmed case of swine influenza A (H1N1) virus infection during case’s infectious period
§ close contact defined as within about 6 feet of ill person
§ infectious period defined as 1 day prior to illness onset to 7 days after onset
§ travel to or residence in area with confirmed cases of swine influenza A (H1N1) virus infection
· WHO definitions
o confirmed case - person with swine influenza A (H1N1) virus infection laboratory confirmed by e 1 of
§ real-time RT-PCR
§ viral culture
§ 4-fold rise in swine influenza A(H1N1) virus specific neutralizing antibodies
o probable case - either of
§ person with influenza test positive for influenza A, but unsubtypable by reagents used to detect seasonal influenza virus infection
§ person with clinically compatible illness or who died of unexplained acute respiratory illness who is considered to be epidemiologically linked to probable or confirmed case
o Reference - WHO interim guidance for surveillance of human infection with swine influenza A (H1N1) virus (WHO 2009 Apr 27 PDF)
· many variations of swine flu viruses exist(1)
· 4 main influenza type A virus subtypes isolated in pigs(1)
o H1N1
o H1N2
o H3N2
o H3N1
· respiratory tract
· persons with direct exposure to infected pigs, such as(1)
o workers in swine industry
o children near pigs at livestock exhibit or fair
·
most cases reported in
· characteristics of 50 cases identified in literature review (search date 2006 Apr)(3)
o
13 cases involved military personnel in outbreak
at
o among 37 civilian cases
§ 20 cases described as healthy
§ 22 cases reported recent exposure to pigs, 14 had no known swine exposure
· reported cases of swine influenza A (H1N1) in humans in 2009
o
§ 45 in New York City, 10 in California, 6 in Texas, 2 in Kansas, 1 in Ohio
§ Reference - CDC Swine Flu website
§ all mild cases with similar genetic pattern based on earlier report
§ all confirmed cases had mild influenza-like illness, only 1 required brief hospitalization
§ all 20 viruses have same genetic pattern on preliminary testing, being described as new subtype of influenza A (H1N1)
§ Reference - WHO Disease Outbreak News 2009 Apr 26
§
initial report of previously unidentified
swine influenza A (H1N1) reported in 2 children in
o
§
12 cases are genetically identical to swine
influenza A (H1N1) viruses from
§ suspect clinical cases have been reported in 19 of 32 states
§ 3 separate outbreaks of influenza-like illness reported (not all cases necessarily represent swine influenza activity)
§
Federal District of
§
§
§ Reference - WHO Disease Outbreak News 2009 Apr 27, WHO Disease Outbreak News 2009 Apr 26, WHO Disease Outbreak News 2009 Apr 24
§
Health Secretary of
o
§ 4 students in Nova Scotia (1 of whom had recent travel to Mexico)
§ 2 people in British Columbia with recent travel to Mexico
§ Reference - WHO Disease Outbreak News 2009 Apr 27, CBCnew.ca 2009 Apr 27
o New Zealand - 3 confirmed cases (all students with recent travel to Mexico)(WHO Press Briefing 2009 Apr 28)
o Spain - 2 confirmed cases (WHO Press Briefing 2009 Apr 28)
o Scotland - 2 confirmed cases in patients with recent travel to Mexico (WHO Press Briefing 2009 Apr 28, BBC News 2009 Apr 27)
o Israel - 2 confirmed cases based on news reports (Jerusalem Post.com 2009 Apr 28) (not noted on CDC or WHO websites as of 2009 Apr 28)
· 12 cases were reported to CDC in United States from 2005 Dec through 2009 Feb, prior estimate of about 1 human swine influenza infection every 1-2 years in United States(1)
· 50 cases identified in literature review (search date 2006 Apr)(3)
o 13 cases involved military personnel in outbreak at Fort Dix, New Jersey
o geographic location of civilian cases
§ United States (19 cases)
§ Czechoslovakia (6 cases
§ The Netherlands (4 cases)
§ Russia (3 cases)
§ Switzerland (3 cases)
§ Canada (1 case)
§ Hong Kong (1 case)
· influenza type A H1N1 virus from pigs(1)
· 2009 Apr outbreak due to newly identified swine influenza virus A/California/04/2009 A(H1N1) (WHO viral gene sequences to assist update diagnostics for swine influenza A(H1N1) 2009 Apr 25 PDF)
· among 50 cases identified in literature review (search date 2006 Apr)(3)
o H3N2 viruses isolated in 4 cases
o H1N1 viruses isolated in all other cases
· pigs are main virus reservoir(1)
· viral transmission(1)
o pigs to humans
o humans to pigs
o human to human through same mechanisms as seasonal flu (such as coughing, sneezing or touching something flu virus and then touching mouth or nose)
· infectious period for confirmed case of swine influenza A (H1N1) virus infection - 1 day prior to illness onset to 7 days after onset(2)
· incubation period 2-7 days (CDC Briefing on Public Health Investigation of Human Cases of Swine Influenza 2009 Apr 28)
· 20 cases in United States in 2009 have same genetic pattern on preliminary testing, being described as new subtype of influenza A (H1N1) (WHO Disease Outbreak News 2009 Apr 26)
· direct exposure to infected pigs, such as(1)
o workers in swine industry
o children near pigs at livestock exhibit or fair
· geographic proximity or close contact to confirmed human cases of swine influenza A (H1N1)(2)
o specific areas in United States (for 2009 outbreak)
o recent travel to Mexico (for 2009 outbreak)
· virus transmission between persons with close personal contact (such as from patient to healthcare provider)(1)
Factors not associated
with increased risk:
· swine influenza viruses not transmitted by eating pork or pork products(1)
o swine influenza viruses not transmitted by food
o cooking pork to internal temperature of 160 degrees F (71.1 degrees C) kills swine flu virus
Complications
and Associated Conditions
· high-risk patient for complications of swine influenza defined as patient who is at high-risk for complications of seasonal influenza(2)
o chronic medical conditions
o aged e 65 years
o aged d 5 years
o pregnant women
· symptoms expected to be similar to human seasonal influenza, including(1)
o fever
o lethargy
o lack of appetite
o cough
· additional symptoms that have been reported(1)
o runny nose
o sore throat
o nausea
o vomiting
o diarrhea
· relevant history specific to 2009 outbreak(2)
o ask about recent travel to Mexico
o ask about contact with patients who had febrile respiratory illness who were in Mexico or areas of United States with confirmed swine influenza cases in 7 days preceding onset of illness
· ask about direct exposure to infected pigs, such as(1)
o workers in swine industry
o children near pigs at livestock exhibit or fair
· fever(1)
· no specific signs rule in or rule out influenza
· CDC definitions(2)
o confirmed case - person with acute respiratory illness with swine influenza A (H1N1) virus infection laboratory confirmed at CDC by e 1 of
§ real-time reverse transcriptase polymerase chain reaction (RT-PCR)
§ viral culture
o probable case - person with acute febrile respiratory illness who is
§ positive for influenza A, but negative for H1 and H3 by influenza RT-PCR
§ positive for influenza A by influenza rapid test or influenza immunofluorescence assay (IFA) plus meets criteria for suspected case
o suspected case - person with acute respiratory illness (defined as recent onset of e 2 of rhinorrhea or nasal congestion, sore throat, or cough) plus either of
§ close contact to confirmed case of swine influenza A (H1N1) virus infection during case’s infectious period
§ close contact defined as within about 6 feet of ill person
§ infectious period defined as 1 day prior to illness onset to 7 days after onset
§ travel to or residence in area with confirmed cases of swine influenza A (H1N1) virus infection
· WHO definitions
o confirmed case - person with swine influenza A (H1N1) virus infection laboratory confirmed by e 1 of
§ real-time RT-PCR
§ viral culture
§ 4-fold rise in swine influenza A(H1N1) virus specific neutralizing antibodies
o probable case - either of
§ person with influenza test positive for influenza A, but unsubtypable by reagents used to detect seasonal influenza virus infection
§ person with clinically compatible illness or who died of unexplained acute respiratory illness who is considered to be epidemiologically linked to probable or confirmed case
o Reference - WHO interim guidance for surveillance of human infection with swine influenza A (H1N1) virus (WHO 2009 Apr 27 PDF)
· influenza (non-avian, non-swine)
· severe acute respiratory syndrome (SARS)
· RSV flu-like syndrome - difficult to distinguish clinically
· carbon monoxide poisoning - consider if entire family has "flu" in winter
· bacterial respiratory infection
· collect specimen (nasopharyngeal swab/aspirate or nasal wash/aspirate) and send to appropriate public health laboratory for real-time PCR testing for influenza A, B, H1 and H3
o swab should have synthetic tip on plastic or aluminum shaft
o place in sterile viral transport media
o maintain at 4°C (39.2°F) until shipped on dry ice in appropriate packaging
· rapid antigen tests and immunofluorescence tests to detect influenza A viruses may have false negative tests due to low sensitivity (WHO Guidance to Influenza Laboratories 2009 Apr 25 PDF, CDC Interim Guidance on Specimen Collection and Processing for Patients with Suspected Swine Influenza A (H1N1) Virus Infection 2009 Apr 28)
· respiratory swab generally needed in first 4-5 days of illness for viral detection, but some persons (especially children) may shed virus for > 10 days(1)
· all unsubtypable influenza A specimens are strongly recommended to be sent immediately to 1 of 5 WHO Collaborating Centres for influenza diagnosis and further characterization (WHO Guidance to Influenza Laboratories 2009 Apr 25 PDF)
· among 64 confirmed cases in United States in 2009
o most had mild influenza-like illness, 5 required hospitalization
o no deaths have been reported
o Reference - CDC Briefing on Public Health Investigation of Human Cases of Swine Influenza 2009 Apr 28
· among 26 cases confirmed in Mexico, 7 deaths reported (WHO Disease Outbreak News 2009 Apr 27)
· 7 deaths reported among 50 cases identified in literature review (search date 2006 Apr), including 1 soldier from outbreak in Fort Dix, New Jersey(3)
· case reports of fatal swine influenza
o 32-year-old pregnant woman hospitalized for pneumonia caused by swine influenza (Arch Intern Med 1990 Jan;150(1):213)
o immunocompetent women who developed adult respiratory distress syndrome caused by swine influenza (Mayo Clin Proc 1998 Mar;73(3):243)
· recommendations may change as data on antiviral susceptibilities become available
o antiviral resistance testing for cases of swine influenza A (H1N1) virus infection detected in United States as of 2009 Apr 25 finds 100% susceptibility to oseltamivir (Tamiflu) or zanamivir (Relenza) and 100% resistance to adamantanes (amantadine or rimantadine)
o seasonal influenza virus antiviral sensitivities vary with subtype
· antiviral treatment for 5 days
o oseltamivir 75 mg orally twice daily (modified dosing for children < 13 years old)
o zanamivir 10 mg via inhaler twice daily
· avoid aspirin in children d 18 years old due to risk of Reye syndrome
· oseltamivir and zanamivir are Pregnancy Category C medications
· preventive measures
o consider antiviral chemoprophylaxis for close contacts
o consider non-pharmaceutical public health interventions (social distancing, respiratory etiquette, facemasks and respirator use) for patients, caregivers, close contacts, healthcare professionals and community
Confirmed, probable, or suspected cases of swine
influenza A (H1N1) virus infection:
· recommendations may change as data on antiviral susceptibilities become available(2)
· initiate treatment as soon as possible after development of symptoms
· treat with 1 of following regimens for 5 days(2)
o oseltamivir orally
§ adults and children e 13 years old - 75 mg twice daily
§ children aged 1-12 years - dosing based on weight
§ d 15 kg - 30 mg twice daily
§ 15-23 kg - 45 mg twice daily
§ 23-40 kg - 60 mg twice daily
§ > 40 kg - 75 mg twice daily
§ children < 1 year old
§ < 3 months old - 12 mg twice daily
§ 3-5 months - 20 mg twice daily
§ 6-11 months - 25 mg twice daily
o zanamivir - 10 mg (2 inhalations) twice daily for adults and children e 7 years old
Special considerations:
· children d 18 years old(2)
o do not give aspirin or aspirin-containing products (such as bismuth subsalicylate [Pepto Bismol]) to any confirmed or suspected case of swine influenza A (H1N1) virus infection due to risk of Reye syndrome
o other antipyretic medications recommended (such as acetaminophen or non-steroidal anti-inflammatory drugs [NSAIDs]) for relief of fever
· pregnancy(2)
o oseltamivir and zanamivir are Pregnancy Category C medications
o use during pregnancy recommended only if potential benefit justifies potential risk to embryo or fetus
o some experts prefer zanamivir for pregnant women because inhaled medication reduces amount of systemic absorption and fetal exposure
· FDA issued Emergency Use Authorizations allowing
o use of Tamiflu to treat and prevent influenza in children < 1 year old, and to provide alternate dosing recommendations for children > 1 year old
o distribution of Tamiflu and Relenza to large segments of population without complying with label requirements
o Reference - FDA Press Release 2009 Apr 27
· different antiviral susceptibilities for seasonal influenza and swine influenza(2)
o swine influenza A (H1N1)
§ antiviral resistance testing results for cases of swine influenza A (H1N1) virus infection detected in United States as of 2009 Apr 25
§ none of 7 isolates tested were resistant to oseltamivir or zanamivir
§ 15 of 15 isolates tested were resistant to adamantanes
§ Reference - CDC 2009 Apr 25; accessed 2009 Apr 26
o seasonal human influenza A and B viruses circulating at low levels in United States and Mexico
§ currently circulating human influenza A (H1N1) viruses
§ sensitive to zanamivir, amantadine and rimantadine
§ resistant to oseltamivir
§ currently circulating human influenza A (H3N2) viruses resistant to amantadine and rimantadine
§ sensitive to zanamivir and oseltamivir
§ resistant to amantadine and rimantadine
· CDC in United States (800-232-4636)
Travel precautions:
· CDC recommends avoiding nonessential travel to Mexico due to swine influenza and severe respiratory illness reported in 19 of Mexico's 32 states (CDC Travel Health Warning 2009 Apr 27)
· information on risk of swine flu in travelers to affected areas can be found at CDC Traveler's Health Announcement 2009 Apr 26
Vaccination:
· no vaccine available to protect humans from swine flu(1)
o vaccine for human seasonal influenza does not protect against H1N1 swine flu viruses due to antigenic differences
o seasonal influenza vaccine may provide partial protection against swine H3N2 virus
·
Centers for Disease Control (CDC) interim
guidance on antiviral
chemoprophylaxis(2)
o
indications for antiviral chemoprophylaxis
with either
oseltamivir
or
zanamivir
§
antiviral chemoprophylaxis, pre- or post-exposure,
recommended for
§
household close contacts (of confirmed, probable,
or suspected case) at high-risk for complications of influenza
§
chronic medical conditions
§
aged e 65 years
§
aged d 5 years
§
pregnant women
§
school children at high-risk for complications
of influenza (certain chronic medical conditions) who had close contact
(face-to-face) with confirmed, probable, or suspected case
§
travelers to Mexico at high-risk for complications
of influenza
§
healthcare workers or public health workers
who had unprotected close contact with ill confirmed, probable, or suspected
case of swine influenza A (H1N1) virus infection during the case’s
infectious period
§
consider pre-exposure antiviral chemoprophylaxis
for
§
any healthcare worker at high-risk for
complications of influenza (persons with certain chronic medical conditions,
elderly) working in area with confirmed swine influenza A (H1N1) cases, or
who is caring for patients with any acute febrile respiratory illness
§
non-high risk travelers to Mexico, first
responders, or border workers who are working in areas with confirmed cases
of swine influenza A (H1N1) virus infection
o
chemoprophylaxis treatment
§
pre-exposure - treat during exposure period
and for 10 days after last known exposure to ill confirmed case of swine
influenza A (H1N1) virus infection
§
post-exposure - treat for 10 days after last
known exposure to ill confirmed case of swine influenza A (H1N1) virus infection
§
dosing
§
zanamivir
- 10 mg (2 inhalations) once daily for adults and children e 5 years old
§
oseltamivir
orally
§
adults and children e 13 years old - 75 mg
once daily
§
children aged 1-12 years - dose based on weight
§
< 15 kg - 30 mg once daily
§
15-23 kg - 45 mg once daily
§
23-40 kg - 60 mg once daily
§
> 40 kg - 75 mg once daily
§
children < 1 year old
§
< 3 months old - not recommended unless
situation critical
§
3-5 months - 20 mg once daily
§
6-11 months - 25 mg once daily
Non-pharmaceutical public health
interventions:
General precautions:
·
frequent handwashing
·
covering coughs and sneezes
·
advising ill persons to stay home (except
to seek medical care) and minimize contact with others in household
·
additional measures that can limit transmission
of new influenza strain
o
voluntary home quarantine of members of households
with confirmed or probable swine influenza cases
o
reduction of unnecessary social contacts
o
avoidance of crowded settings when possible
CDC Interim Recommendations for Facemask and Respirator
Use:
·
avoiding close contacts and crowded settings
preferable to facemask and respirator use whenever possible
·
in areas where transmission of swine influenza
A (H1N1) has been confirmed
o
consider facemasks (disposable masks) for
persons who enter crowded settings
o
consider respirators (N95 or higher filtering
facepiece respirator) for persons who have unavoidable close contact with
infectious person
CDC Interim Guidance for infection control for care of infected patients
in healthcare setting:
·
place patients with suspected or confirmed
case in single-patient room with door kept closed
·
airborne infection isolation room with negative
pressure air handling can be used if available
o
6-12 air changes per hour
o
air can be exhausted directly outside or
recirculated after filtration by high efficiency particulate air (HEPA) filter
·
use procedure room with negative pressure
air handling for suctioning, bronchoscopy or intubation
·
ill patient should wear surgical mask when
outside of patient room, wash hands frequently and follow respiratory hygiene
practices
·
precautions for healthcare providers
o
use standard, droplet and contact precautions
for all patient care activities for 7 days after illness onset or until symptoms
resolved
o
maintain adherence to hand hygiene by washing
with soap and water or using hand sanitizer immediately after removing gloves
and other equipment and after any contact with respiratory secretions
o
wear disposable non-sterile gloves, gowns
and eye protection when providing care or collecting clinical specimens
o
fit-tested disposable N95 respirator should
be worn by
§
personnel providing direct patient care for
suspected or confirmed swine influenza A (H1N1) cases when entering patient
room
§
personnel involved in aerosol-generating
activities (such as collection of clinical specimens, endotracheal intubation,
nebulizer treatment, bronchoscopy)
CDC Interim Guidance for Nonpharmaceutical Community Mitigation in Response
to Human Infections with Swine Influenza (H1N1) Virus:
·
recommendations if confirmed human infection
with swine influenza A (H1N1) in a community
o
home isolation of cases strongly recommended
§
self-isolation recommended for 7 days after
onset of illness or e 24 hours after symptoms resolved (whichever is longer)
§
persons who experience influenza-like illness
should contact healthcare provider by telephone or other remote option before
leaving house to seek care
§
seek immediate medical attention for persons
who have difficulty breathing or shortness of breath or are believed to be
severely ill
o
household contacts who are well should
§
remain home at earliest sign of illness
§
minimize contact in community
§
designate single household family member as
ill person's caregiver to minimize interactions with asymptomatic persons
o
schools and childcare facilities should consider
dismissing students in schools with confirmed or suspected case
§
cancel all school or childcare related gatherings
if school dismisses students or childcare facility closes, encourage parents
and students to avoid congregating outside of school
§
local authorities should make decision regarding
broader school dismissal within community
§
evaluate time period for dismissal on ongoing
basis
§
consult with local or state health departments
for guidance on reopening (consider reopening if no additional confirmed
or suspected cases identified among students or personnel for 7 days)
o
other social distancing interventions
§
large gatherings linked to settings or
institutions with laboratory-confirmed cases shoudl be cancelled
§
additional social distancing measures not
recommended
·
schools and childcare facilities in unaffected
areas should prepare for possibility of school dismissal or childcare facility
closure
Systematic review:
·
non-pharmaceutical public health interventions
for pandemic influenza
(grade
C recommendation [lacking direct evidence]) based on systematic review
with lack of evidence so based on expert opinion
o
hand hygiene
o
respiratory etiquette (covering mouth and
nose with tissue or into upper sleeve when coughing or sneezing, refraining
from spitting)
o
surveillance and case reporting
o
rapid viral diagnosis
o
patient and provider use of masks and other
personal protective equipment
o
voluntary self-isolation of patients
o
interventions rejected as likely to be ineffective
or unacceptable
§
mask use and other personal protective equipment
for general public
§
school and workplace closures early in epidemic
§
mandatory travel restrictions
o
Reference -
BMC Public Health 2007 Aug 15;7:208
full-text
·
1. Centers for Disease Control and Prevention.
Key Facts about Swine Influenza (Swine Flu).
CDC
2009 Apr 24; accessed 2009 Apr 24.
·
2. Centers for Disease Control and Prevention
interim guidance on antiviral recommendations for patients with confirmed
or suspected swine influenza A (H1N1) virus infection and close contacts
can be found at
CDC
2009 Apr 28; accessed 2009 Apr 28.
·
3. Myers KP, Olsen CW, Gray GC. Cases of swine
influenza in humans: a review of the literature.
Clin Infect Dis. 2007 Apr 15;44(8):1084-8.
full-text
·
MEDLINE search 2009 Apr 26 using PubMed Clinical
Queries (therapy [broad, sensitive search]) for "H1N1 AND ("swine flu" OR
"swine influenza")" Click for
Details
o
Click here to repeat MEDLINE search
o
0 studies included in this summary
o
25 studies not included in this summary
§
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§
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·
Public Health Agency of Canada Human Swine Influenza
website
·
Ministry
of Health of Mexico (Spanish)
·
review can be found in
J Infect Dis 2008 Feb 15;197 Suppl 1:S19
·
CDC interim guidance documents can be found
at CDC Swine
Flu Guidance
o
CDC interim guidance on antiviral recommendations
for patients with confirmed or suspected swine influenza A (H1N1) virus infection
and close contacts can be found at
CDC
2009 Apr 28
o
interim CDC guidance on nonpharmaceutical
community mitigation in response to human infections with swine influenza
(H1N1) virus can be found at
CDC
2009 Apr 26
·
WHO interim guidance for surveillance of human
infection with swine influenza A (H1N1) virus can be found at
WHO 2009 Apr 27 PDF
·
WHO Guidance Document on Pandemic Influenza Preparedness
and Response
PDF
·
information from CDC
o
key facts from
CDC
or in
Spanish
o
swine influenza and you (questions and answers)
from
CDC
or in
Spanish
o
general information on swine influenza in
pigs and people from
CDC
PDF
o
taking care of sick person at home
CDC
·
frequently asked questions from
World
Health Organization PDF
·
fact sheet from
Public Health Agency of Canada
·
frequently asked questions from
Public Health Agency of Canada
·
handout from
Massachusetts Department of Public Health PDF
·
handout from
EBSCO Publishing Health Library
PDF
·
DynaMed topics are created and maintained
by the
DynaMed
Editorial Team.
References
including Reviews and Guidelines
EBSCOhost
Full Text
EBSCOhost
Full Text