1. The document provides guidelines for the clinical case management of outbreaks of influenza-like illness (ILI), including definitions, assessment, and treatment recommendations. 2. It defines ILI and outlines criteria for classifying patients into mild, mild but high-risk, or severe ILI. Patients are assessed for symptoms, risk factors, and disease progression over 72 hours. 3. Treatment recommendations include symptomatic care for mild ILI, antivirals for mild ILI in high-risk groups, and antivirals in a hospital for severe ILI. Laboratory testing and hospital admission are based on illness severity and risk status.

1. 1 | P a g e
Clinical Case Management
of Outbreaks of Influenza-
Like Illness
By
Dr. Ashraf El-Adawy
Consultant Chest Physcian
TB TEAM Expert – WHO
Mansoura-Egypt

2. 2 | P a g e
Clinical Case Management of Outbreaks of Influenza-Like Illness
Rapid Guide To Assessment and Management Of ILI
Case Definition
Influenza-like-illness (ILI)
A person with sudden onset of fever of ≥ 38°C and cough or sore
throat, within the last seven days, in the absence of other known
causes other than influenza.
 Even though influenza can be caused by many different strains of influenza
virus, the signs and symptoms are similar for all types.
 In addition to the influenza viruses, other respiratory viruses can also cause ILI
symptoms, such as human respiratory syncytial virus , human parainfluenza
viruses , rhinovirus, adenovirus, human coronaviruses and human
metapneumovirus .
 The range of symptoms observed with influenza virus infections is nonspecific
and resembles the clinical picture of a variety of other pathogens. There is no
single symptom or group of symptoms that is exclusive only to influenza.
 Patients who meet ILI criteria should be reported even in the absence of
confirmatory lab tests.
 Although this clinical definition by itself is very general, when combined with
information on circulating viruses, the information on ILI activity provides an
excellent picture of influenza activity in the community.
 Please report only those patients that meet the ILI case definition. For
example, a patient with fever, chills, body aches, and nasal congestion but no
cough or sore throat is not considered a case of ILI.
Guide to assessment and management of ILI
 Since a wide range of pathogens can cause influenza‐like illness (ILI), a clinical
diagnosis of influenza should be guided by clinical and epidemiologic data and
can be confirmed by laboratory tests.
 However, on an individual patient basis, initial treatment decisions should be
based on clinical presentation and epidemiological data and should not be

3. 3 | P a g e
delayed pending laboratory confirmation , a decision to treat will depend
upon clinical judgment.
 The clinical presentation of influenza can vary from asymptomatic infection to
a serious fatal illness that may include exacerbation of other underlying
conditions and severe viral pneumonia ,ARDS ,with multi‐organ failure.
 The clinical management of influenza‐like illnesses will follow a protocolized
step in both the primary and secondary or tertiary level health care facilities.
 The clinical assessment should ideally begin in the triage area whenever a
patient is suspected of ILI.
 The assessment will lead to screening out of patients for treatment from those
without having any visible signs or symptoms of ILI requiring no treatment.
Assessment of suspected cases with ILI at the primary health care level
 Influenza can be diagnosed based on clinical presentation in the context of
known or suspected influenza activity in your community and should be part
of a broader differential diagnosis in patients with severe ARI.
 Assess general state
 Assess hydration
 Measure the body temperature (fever ≥ 38°C)
 Measure the respiratory rate
 Observe sub‐costal recession or nasal flaring
 Observe the colour of the skin, nails and mucosa
 Perform pulmonary auscultation to detect crepitations
Triage and emergency care
 Triage all patients with acute respiratory illnesses immediately upon
arrival to the hospital. Triage means to sort patients into priority
categories:

4. 4 | P a g e
1) Mild or non-severe influenza-like illness (ILI)
 The basic definition of influenza-like (ILI) illness includes: Presence of some or
all of the following signs and symptoms: Fever, cough, sore throat, rhinorrhea,
headache, muscle pain, or malaise.
 Gastrointestinal illness such as diarrhoea or vomiting may also be present.
 There should be NO shortness of breath or evidence of dehydration in patients
with uncomplicated ILI.
 The general condition of these patients will be good without any signs of
hypotension or mental confusion.
 Patients presenting only with mild influenza like illness but excluding
those at‐risk groups for complications and without any clinical signs of
progression to severe illness can be treated at home with symptomatic
treatment . These group of patients need not be treated with antiviral
medication.
2) Mild or non-severe influenza-like illness (ILI) in high risk groups:
 In Patients who meet ILI clinical case definition and in high risk group for
serious or life-threatening influenza complication (with stable medical
condition) for example :
• Pregnant women (up to two weeks post partum)
•age <2 years or ≥65 years
• Persons with the following underlying conditions at any age:
- Chronic Broncho‐pulmonary disease (Including asthma & COPD& OSA )
- Chronic cardiovascular diseases (Including CHF& MI , except hypertension)
- Metabolic disorder (specially Diabetes mellitus)
- Chronic liver or renal failure
- Chronic neurologic disorder (Cerebral palsy, stroke, multiple sclerosis,
muscular dystrophy, seizure disorders etc)
- Immune suppressed patients (HIV, immunosuppressive medications,
malignancy , long term steroids)
- Haemoglobinopathies
- Morbid obesity(i.e., body-mass index ≥40)

5. 5 | P a g e
 For Mild or non-severe influenza-like illness (ILI) in high risk groups , treat
with antivirals at home, and close home observation with instruction to
return to care if they fail to improve in 72 hours or deteriorate. If this occurs,
hospitalization should be considered.
Prescribing oseltamivir
 Oseltamivir is active against all currently circulating human influenza
viruses.
 The usual dose is 75 mg taken orally twice a day for adults and children
>40 kg for 5 days , In smaller children use weight based dosing.
Management of patients at home
 The principles of treatment at home for these categories of patients include
the followings:
 Applying home isolation and advising rest till the patient becomes afebrile.
 Administering appropriate infection control measures at home.
 Using analgesics or antipyretics, however Acetylsalicylic acid should be
avoided specially in children (The drug of choice should be Acetaminophen).
 Aspirin‐containing products should not be administered to patients aged
18 years old and younger due to the risk of Reye syndrome.
 Hydrating patients with abundant liquids in accordance with the need and
patient’s condition.
 Following‐up clinical evolution of the patient by health care worker or by
family members checking for signs and symptoms of progression to severe
illness & Recognize patients that fail to improve within 72 hrs or deteriorate.
Worsening signs and symptoms signifying rapid progression to severe
Illness
 Shortness of breath , difficulty in breathing, cyanosis, bloody or
colored sputum, chest pain, low blood pressure.
 Fast or laboured breathing in children less than 5 years of age

6. 6 | P a g e
 Altered mental status, unconscious, drowsiness, or difficult to
awaken; recurring or persistent convulsions (seizures), confusion,
severe weakness .
 Persistent or recurrent high fever and other symptoms beyond three
days.
 Decreased activity, dizziness, decreased urine output, lethargy.
 Children can also present with stridor, poor feeding, and excessive
diarrhea and vomiting.
 If the patient fail to improve or deteriorate ,develops severe symptoms
within 72 hours , admit patient to hospital for screening &treatment.
 Regading decision making algorithm for the patient presenting with
Mild , uncomplicated influenza-like illness (ILI) , It takes into account the
presence or absence of risk factors for severe disease and on the
progression & deterioration of the disease over 72 hours.
3) Recognize patients with severe infection “Diagnosis of severe influenza
-like illness (ILI)infection”:
 First and foremost is the recognition of the critically ill patient, When influenza
is known or suspected to be circulating widely in the community, patients with
severe forms of influenza infection can present with critical illness (severe
pneumonia and severe acute respiratory distress , severe sepsis, septic shock,
or any end-organ dysfunction (shock, encephalitis, myocarditis).
Importance of early recognition
− Routine screening & early recognition of clinical syndromes (i.e. severe sepsis,
severe pneumonia, and ARDS) and implementation of appropriate therapies,
improves outcomes and reduce morality .
− Following clinical assessment of cases, decisions to hospitalize those patients with
suspected ILI symptoms will be taken whenever the following clinical criteria are met:

7. 7 | P a g e
Criteria for hospitalization (Signs of severe like illness (ILI) or signs of rapid
progression of illness, such as :
 Presence of fever ≥ 38°C
 Dyspnoea or difficult breathing
 Cyanosis, bloody or colored sputum, chest pain
 Hypoxia as indicated by pulse oximetry ( Oxygen saturation < 92% despite full
oxygen saturation)
 Alteration of vital sign : Arterial hypotension (Systolic blood pressure <90 mm Hg
and diastolic blood pressure < 60 mm Hg) ,Respiratory frequency increased
(over 30 breaths per minute) , Cardiac frequency increased (Heart rate > 120bpm)
 Altered level of consciousness: New confusion, striking agitation or seizures
 Severe Dehydration (Loss of more than 10 % of body weight as evidenced by
absent or low peripheral pulse, poor skin turgor, undetectable blood pressure
and sunken eyes)
 Abnormal chest‐x ray (Chest x‐ray showing pulmonary infiltrates)
 Patient that return for a second consultation with recurrent or persistent fever
( fever not subsiding beyond 3 days despite under treatment with analgesics)
Criteria for admission in the Intensive Care Unit :
Patient showing no signs of improvement and remain non‐responsive to antiviral
treatment as evidenced by the followings:
 Signs of progressive infiltrates on chest x‐ray
 Persistent hypoxia ( SpO2 < 92%) or respiratory exhaustion despite maximum
oxygen saturation
 Progressive hypercapnoea
 Presence of compromised haemodynamics
 Signs of sepsis and imminent shock
 Antiviral Treatment using oseltamivir is recommended for all
hospitalized Patients & should be initiated empirically as early as
possible (i.e. within 48 hours of illness onset) .
 When the decision is made to treat patients in the hospitals who have
illnesses that are clinically compatible with influenza, Treatment should
not await laboratory confirmation.
 Clinical judgment is an important factor in antiviral treatment decisions.

8. 8 | P a g e
 When secondary bacterial pneumonia is suspected, treatment with
antibiotics should follow recommendations from national guidelines for
community‐acquired pneumonia.
Diagnostic tests:
 When influenza viruses are known to be circulating in a community, patients
presenting with features of uncomplicated influenza( Mild ILI with or without
high risk factors of developing severe or complicated illness ) can be
diagnosed on clinical and epidemiological grounds, will not rquire influenza
laboratory confirmation.
 Respiratory tract specimens for influenza testing should be collected as
soon as possible after onset of illness in patients in whom treatment may be
affected by making the diagnosis, such as those with progressive or severe
illness (severe ILI) .
 Collect respiratory specimens for laboratory testing before antiviral therapy is
initiated:
 Upper respiratory tract specimens (nasopharyngeal and nasal specimens
generally have higher yields than throat swab specimens).
 lower respiratory tract specimens, in addition to upper respiratory tract
sampling, In patients with lower respiratory-tract symptoms (i.e. endotracheal
aspirate, bronchoalveolar lavage) .
 Collect Sputum sample (if evidence of Pneumonia)
 Collect pretreatment blood cultures (before antimicrobial therapy is initiated,
If this does not significantly delay (>45 minutes) the start of antimicrobial
therapy) .
 Specimens should be taken as early as possible in the course of illness as the
ability to detect virus declines with increasing delays.
 Reverse transcriptase polymerase chain reaction or RT-PCR are diagnostic
tests of choice for accurate and timely diagnosis of influenza virus infection.
 These tests detect the presence of the virus ribonucleic acid or RNA (a
fragment of the virus) and they can identify the influenza virus (A,B) and
subtypes.
 RT-PCR can be used to detect viral RNA in upper and lower respiratory tract
specimens.
 RT-PCR has both a high sensitivity (86%-100%) and high specificity and
distinguishes specific influenza virus from others.

9. 9 | P a g e
 The test requires a special laboratory and takes about 6-8 hours to perform in
the laboratory but delays may occur during transport to laboratory and
laboratory batching.
 Specimen collection should be always performed with appropriate infection
prevention precautions.
 Under no circumstances should influenza diagnostic testing delay
initiation of infection control practices or antiviral treatment,
if influenza is suspected clinically and epidemiologically.
 Influenza can be diagnosed based on clinical presentation in the context
of known or suspected influenza activity in your community and should
be part of a broader differential diagnosis in patients with severe ARI.
General laboratory investigations for hospitalized patients:
If facilities are available, the following laboratory investigations could be considered
with a view to monitoring the clinical condition of the hospitalized patients:

10. 10 | P a g e
Guide to assessment and management of ILI
(Policy of Laboratory testing and hospital admission for ILI Cases) :
 The following case classification is intended in assisting clinicians on the best
approach to decide on referral decisions & Lab tests. This is not intended on
any way to replace the clinical sense of clinicians.
 Patients should be clinically assessed for hospital admission and treatment
decisions which should be based mainly on the severity of the illness.
STEP 1 Confirm Patient Presents With Influenza-like Illness
STEP 2 Conduct Illness-Severity Assessment
STEP 3 Assess for Co-morbid Conditions
Accordingly cases can be classified into:
1. Mild ILI (Group 1) :
Patients with ILI clinical case definition in low risk people in the absence of other
diagnoses. They will not require laboratory confirmation, or admission to
hospital.
2. Mild ILI in high risk group (Group 2) :
Patients with ILI clinical case definition in high risk people (for serious influenza
complications), with stable medical condition and no serious or life-threatening
influenza complication, and in the absence of other diagnoses. Patients of this
group Do not require laboratory confirmation, or admission to hospital.
3. Severe ILI (Group 3) :
Patients with ILI clinical case definition (whether in high risk people or not) ,with
Unstable medical condition and vulnerable to serious or life-threatening
influenza complication, and in the absence of other diagnoses.. Those Patients
are considered vulnerable to severe outcomes should be the focus of early
identification. They will require laboratory confirmation, and hospital admission.

11. 11 | P a g e
Treatment Flow Chart
Antiviral treatment guidelines for (ILI) can be classified according to the
following groups :
1. Mild ILI : Patients in this group should have only symptomatic treatment
at home.
2. Mild ILI in high risk group : Patients in this group should have antiviral
treatment at home.
3. Severe ILI : Patients in this group should have antiviral treatment in the
hospital .

12. 12 | P a g e
Guide to assessment and management of ILI
ILI: Fever ≥ 38º C AND Cough or sore throat, with onset within
the last seven days, in the absence of other known causes other
than influenza
Q 1: Does the patient has any symptoms & signs of severe illness ?
Q 2 :Does the patient at high risk for severe influenza complications ?
Mild ILL Mild ILL Severe ILL
In high risk groups
ILI clinical case ILI clinical case case ILI clinical case
Stable condition Stable condition Unstable condition
Not in high risk group In high risk group Complicated OR progressive i
NO influenza laboratory test NO influenza laboratory test Influenza laboratory test
NO hospital admission NO hospital admission Hospital admission
Symptomatic treatment Use antiviral treatment Use antiviral treatment
Treated at home Treated at home Treated in hospital
Close home observation with instruction to return for care,
If the patient fail to improve or deteriorate and develops severe
symptoms, within 72 hours ,admit patient to hospital for
screening &treatment

13. 13 | P a g e
Summary of influenza antiviral treatment recommendations:
1. Patients who have Mild ILI (uncomplicated illness), and are not in a group
known to be at higher risk of developing severe or complicated illness, may
not need to be treated with antivirals, only symptomatic treatment, applying
isolation and management of these patients at home.
2. Patients who have Mild ILI (uncomplicated illness) and are in a group known
to be at higher risk of developing severe or complicated illness, should be
treated with a neuraminidase inhibitor such as oseltamivir , applying isolation
and management of these patients at home:
 Treatment should be started as soon as possible ,The usual dose
is 75 mg taken orally twice a day for adults and children >40 kg
for 5 days, In smaller children use weight based dosing.
 Amantadine and Rimantadine should not be used because of the
high levels of resistance to these drugs among circulating
influenza viruses.
 Laboratory confirmation of influenza virus infection is not
necessary for the initiation of Treatment.
 Evidence indicates that the greatest benefit is derived from early
oseltamivir treatment. Therefore, suitable preparations of
oseltamivir need to be available at the point of care.
 All Patients who have uncomplicated illness ,should be instructed to return for
follow-up, when they develop any signs or symptoms of progressive disease or
fail to improve within 72 hours of the onset of symptoms. If this occurs,
hospitalization should be considered.
3. Patients who have severe or progressive clinical illness should be hospitalized
and treated with oseltamivir as soon as possible. Consideration should be
given to the use of higher doses (up to 150 mg twice daily in adults and

14. 14 | P a g e
double the daily dose in children), and longer duration of treatment depending
on clinical response.
Notes:
1. When indicated, antiviral treatment should be started for hospitalized
patients, as soon as possible, ideally within 48 hours of symptom onset,
However, antiviral treatment might still be beneficial in patients with
severe, complicated, or progressive illness when administered >48 hours
from illness onset.
2. Early antiviral treatment can reduce the risk of complications from
influenza (e.g. pneumonia, respiratory failure, and death).
3. The recommended duration of treatment is 5 days, use of increased
(doubled) doses of oseltamivir for severely ill patients
4. Longer treatment regimens might be necessary in severely ill , hospitalized
patients or persons with immunosuppression, if the clinical course remains
severe or progressive, despite ≥5 days of antiviral treatment, treatment
should be continued without a break until virus infection is resolved or
there is a satisfactory clinical improvement (for up to 10 days) .
5. Clinical judgment should be the guide regarding the need to extend
treatment regimens longer than 5 days for patients whose illness is
prolonged.
6. Respiratory tract specimens for influenza testing should be collected as
soon as possible after onset of illness in patients in whom treatment may
be affected by making the diagnosis, such as those with progressive or
severe disease.
7. Don not delay commencement of empiric antiviral treatment plus empiric
antibiotics for community-acquired pathogens, while awaiting
confirmatory diagnostic test results In Patients who have severe or
progressive clinical illness.
8. If microbiologic results identify pathogen, therapy should be tailored
towards this pathogen.
9. Patients with suspected influenza should complete antiviral treatment for a
full treatment course regardless of negative initial test results unless an
alternative diagnosis can be established and clinical judgement suggests
that influenza is an unlikely diagnosis.

15. 15 | P a g e
10. Patients may have co-infection with bacterial pathogens or other
respiratory viruses; therefore, investigations and/or empiric therapy for
other pathogens should also be considered.
Oseltamivir Treatment Dosage (Tamiflu®)
Agent, group Treatment usually for 5 days
Oseltamivir
Adults 75-mg capsule twice per day
Children
≥ 12
months
15 kg or less 60 mg per day divided into 2 doses
16-23 kg 90 mg per day divided into 2 doses
24-40 kg 120 mg per day divided into 2 doses
>40 kg 150 mg per day divided into 2 doses
Oseltamivir Dosage for Children under one Year
Age Recommended treatment of Oseltamivir for
5 days
<3 months 12 mg twice daily usually for 5 days
3-5 months 20 mg twice daily usually for 5 days
6-11 months 25 g twice daily usually for 5 days
 The treatment dosing is the same for pregnant women as other adults:
oseltamivir (Tamiflu) : 75 mg capsule twice/day for 5 days

16. 16 | P a g e
In Persons with Impaired Renal Function
 Serum concentrations of oseltamivir carboxylate, the active metabolite
of oseltamivir, increase with declining renal function .
 For patients with creatinine clearance of 10--30 mL per minute, a
reduction of the treatment dosage of oseltamivir to 75 mg once daily is
recommended.
Points to remember:
 Clinical judgment, on the basis of the patient’s disease severity & progression,
age, underlying medical conditions, likelihood of influenza, , is important to
consider when making antiviral treatment decisions.
 Clinicians should consider influenza virus infection as a possible cause of any
febrile respiratory illness requiring hospitalization during influenza season and
consider testing for influenza and starting empiric antiviral therapy & Do not
wait for laboratory confirmation of diagnosis.
 During an influenza outbreak, cases of pneumonia both from influenza and
from secondary bacterial pneumonia may be expected to increase, adding to
the high burden of pneumonia already seen in community settings.
 Treatment of respiratory infections caused by a primary viral infection with
influenza should follow national and WHO clinical treatment guidelines for the
use of antiviral medications.
 Also recommended antibiotics will depend on the type of bacteria causing the
pneumonia, local resistance patterns, the individual patient contraindications
or allergies, and the national protocol for CAP.
 Persons with influenza like illness who present with an uncomplicated febrile
illness typically do not require antiviral treatment unless they are at higher risk
for serious influenza complications.

17. 17 | P a g e
Discharge criteria for hospitalized patients :
Patient showing clinical signs of improvement and proof of responding to antiviral
treatment as evidenced by the followings:
 Patient becomes afebrile
 Absence of dyspnoea
 Satisfactory oral fluid tolerance
 No signs of dehydration
 Respiratory rate ≤30 bpm
 Oxygen saturation ≥ 92%
 Underlying chronic health conditions not exacerbated in patients in
high‐risk group for complication.

18. 18 | P a g e

19. 19 | P a g e

20. 20 | P a g e