A Winter Free of Cold Understanding the Common Cold and Flu. Camille Aizarani, MD Family Medicine Specialist

Transcription

1 A Winter Free of Cold Understanding the Common Cold and Flu Camille Aizarani, MD Family Medicine Specialist

2 Outline Introduction Is it a cold or flu? The Common Cold Symptoms of Common Cold Tansmission of Common Cold When to see a doctor? Evidence Based Treatment of Common Cold Product Overview Flu-Like Illness Different Types of Influenza Influenza Vaccine

3 Is it a cold or flu? Common cold and flu are illnesses of familiar symptoms caused by viral infection of the upper respiratory tract. It is difficult to define the syndromes exactly because of great variation in the severity, duration, and types of symptoms. Eccles, Ron. "Understanding the symptoms of the common cold and influenza." The Lancet infectious diseases 5.11 (2005):

4 Is it a cold or flu? 30% 50% of all colds are due to a rhinovirus 10% 15% of all colds are due to a coronavirus (2 nd most common agent) 5% 15% of colds are due to an influenza virus There is much overlap in etiology and symptomatology of common cold and flu syndromes. Eccles, Ron. "Understanding the symptoms of the common cold and influenza." The Lancet infectious diseases 5.11 (2005):

5 Common Cold (Le Rhume) Symptoms Common cold causes inflammation of the mucus membranes of the head and throat It is a short and mild illness characterized by headache, sneezing, chilliness, sore throat nasal discharge, nasal obstruction, cough, and malaise Affects persons of all ages Adults have an average of 2-4 episodes annually Young children may have as many as 6 8 episodes

6 Common Cold Symptoms Usually severity of symptoms increases rapidly, peaking 2 3 days after infection Mean duration of symptoms 7 10 days Some symptoms persisting for more than 2 weeks. Rarely a bacterial infection may complicate the illness

7 Infection does not always mean a cold Most viral infections produce no disease at all. They are 'subclinical' (i.e. no symptoms), despite extensive viral replication. The concept that the majority of viral infections pass unnoticed (no signs of disease) is known as the 'iceberg concept of infection.

8 Common Cold Transmission Transmission occurs through: Hands, objects, other surfaces in contact with viruses Air borne droplets while sneezing and/or coughing Incubation of 1-3 days.

9 Common Cold When to see a doctor For adults seek medical attention if you have: Fever of 39 C or higher lasting more than 2 days Fever accompanied by sweating, chills and a cough with colored phlegm Significantly swollen glands Severe sinus pain

10 Common Cold When to see a doctor For children seek medical attention if: Fever of (38 C) in newborns up to 12 weeks Fever that rises repeatedly above (40 C) in a child of any age Signs of dehydration, such as urinating less often than usual Not drinking adequate fluids Fever that lasts more than 24 hours in a child younger than 2 Fever that lasts more than 3 days in a child older than 2

11 Common Cold When to see a doctor For children seek medical attention if: Vomiting or abdominal pain Unusual sleepiness Severe headache Stiff neck Persistent crying Ear pain Persistent cough Difficulty breathing

12 Evidence Based Treatments of Common Cold

13 Overview of the Evidence for Cold Therapies in Adults

14 Overview of the Evidence for Cold Therapies in Adults

15 Overview of the Evidence for Cold Therapies in Children

16 Common Cold

17 Treatment of Common Cold H1 Anti-histamines Efficient on rhinorrhea reduce runny nose Sedative effect Induce dryness of the mouth and eyes, Contra-indicated in cases of glaucoma Examples : Doxylamine, Chlorphénamine, Phéniramine Medications available in the market Vasoconstrictors with anti H1 Vasoconstrictors + anti-histamine + antipyretic

18 Non Pharmacological treatment Patients and parents education Pharmacological treatment Diagnosis by history +/- SPT/specific IgE Allergen/ Irritant avoidance +/- nasal douching moderat e/severe Symptoms Topical nasal steroid* mild Oral/Topical nonsedating antihistamines a- H1 Rhinitis Treatment Algorithm Allergen avoidance Nasal douching and drops Rx failure Check use, compliance, increase dose +/or OC Rx failure *Spray or drops. OC, oral corticosteroids; a-h1, antihistamines; LTRA, leukotriene receptor antagonist; Sx, symptoms; Rx, treatment; SPT, skin prick test British Society for Allergy and Clinical Immunology (BSACI) guidlines, G.K. Scadding, clinical and experimental allergy, 2008, volume 38, pages Watery rhinorrhoea Add ipratropium Infection structural problem Surgical referral Itch/sneeze Add nonsedating α- H1 Rx failure Consider immunotherapy if Sx predominantly due to one allergen Catarrh Add LTRA if asthmatic Blockage Add (briefly) -decongestant -or OC -or longer term long-acting non-sedating α-h1 topical azelastine/ltr A)

19 Treatment of Common Cold Vasoconstrictors (15 years and above) Vasoconstriction effect decongestion of mucosa, better breathing Contra-indicated in case of : HTN, previous episode of stroke, coronary artery disease, glaucoma, prostatic disease Side effects: headache, palpitations, tachychardia, hypertensive crises, sweating, glaucoma by closure of the occular angle, urinary problems (retention, dysuria), anxiety, insomnia, dry mouth, nausea, vomitting Examples: Phénylephrine, Pseudoéphédrine Product either tablets or nasal spray

20 OTC Product against common cold Product/ Composition Day formulation Night formulation Paracetamol 500mg 500mg Pseudoephedrine 30 mg Doxylamine 7.5 mg

21 Indications: cold treatment congested nose, runny nose, headaches and/or fever. In the absence of improvement after four days of treatment, it is necessary to seek medical advice. Dosage and Administration: Reserved for adults and children over 15 years old. During the day: 1 oblong tablet to renew if necessary after a minimal dosing interval of 4 hours with a maximum daily dose of 3 tablets. In the evening: 1 round tablet if necessary. In severe renal failure: minimum dosing interval should be 8 hours, not exceed paracetamol daily dose of 3 g; Product Information

22 Objective: Evaluate the effectiveness of a combination of pseudoephedrine hydrochloride and acetaminophen in relieving sinus symptoms in patients with a cold.

23 Method: Randomized, blinded placebo controlled trial. 412 patients who were years of age (mean age 28y, 66% women) had cold symptoms of <48 hours in duration, Only those who reported sinus symptoms of at least moderate severity were selected. Patients were allocated to: Pseudoephedrine, 60 mg, and acetaminophen, 1000 mg (n = 216) Identical placebo tablets (n = 214). The drugs were given in 2 doses, 6 hours apart.

24 Results Analysis was by intention to treat. 2 hours after the second dose of medication: Patients who received PHA had a greater decrease in overall sinus assessment score than did patients who received placebo (p < 0.001), in the sinus weighted score (p < 0.001).

25 Objective: This study compared the efficacy of 1000 mg of paracetamol combined with 60 mg of pseudoephedrine, with that of either 1000 mg paracetamol or 60 mg pseudoephedrine alone and placebo for the treatment of symptomatic upper respiratory tract infection (URTI).

26 Research design and methods: A double-blind, parallel group study 305 patients with URTI (nasal airflow resistance [NAR] of > 0.25 and a global pain score of at least moderate intensity). NAR and pain relief/ intensity scores were measured over 4 h after initial dose. Patients then dosed up to three times daily for 3 days and recorded nasal congestion and pain intensity scores.

27 Results: A single dose of the combination was superior to paracetamol and placebo for NAR ( p = ) and was superior to pseudoephedrine and placebo for pain relief ( p 0.048). Multiple doses of the combination were also superior to paracetamol and placebo for decongestion ( p 0.021) and were superior to pseudoephedrine and placebo for pain reduction ( p ). All treatments were well tolerated.

28 What is the flu-like illness? (L état grippal) All symptoms suggestive of flu, but without the presence of the influenza virus. Caused by respiratory viruses, such as those responsible for the common cold, pharyngitis, bronchitis Symptoms are similar to those of influenza: fever, headache, runny nose Symptoms are worse than common cold but less than the flu.

29 How to treat flu-like illness It can be treated by the combination of nasal washing, antihistamines or vasoconstrictors, analgesics and antipyretics. In most cases, treatment of the flu-like illness is to alleviate symptoms for a faster relief

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32 Influenza Syndrome (La grippe) Typically of sudden onset Characterized by fever, headache, cough, sore throat, myalgia, nasal congestion, weakness, and loss of appetite. The early clinical diagnosis of influenza as opposed to common cold is very important! The best predictors for influenza are cough and fever This combination of symptoms has been shown to have a positive predictive value of around 80% in differentiating influenza from flu-like symptoms.

33 What Are the Different Types of Influenza? There are three types of flu viruses: A, B, and C. Type A and B cause the annual influenza epidemics Type C also causes flu; however, type C flu symptoms are much less severe. The flu is linked to between 3,000 and 49,000 deaths and 200,000 hospitalizations each year in the United States. The seasonal flu vaccine was created to try to avert these epidemics.

34 What Are the Different Types of Influenza? Wild birds commonly act as the hosts

35 Flu vaccines available Standard-dose trivalent shots that are manufactured using virus grown in eggs. They are approved for people of different ages. Some are approved for use in people as young as 6 months of age.

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37 When should I get vaccinated? Begin soon after vaccine becomes available, if possible by September. Since it takes about two weeks after vaccination for antibodies to develop, it is best that people get vaccinated so they are protected BEFORE influenza begins spreading in their community. While seasonal influenza outbreaks can happen as early as October, influenza activity peaks in January or later. As long as flu viruses are circulating, vaccination should continue to be offered throughout the flu season, even in January or later.

38 Ending Notes

39 Ending notes So why do patients continue to request antibiotics for common infections? Desire to get well better more quickly Better safe than sorry!

40 Ending notes So why do doctors give antibiotics for viral infections? They think you want an antibiotic It s easier than explaining why you don t need one! Patients have been trained to expect them Doctors think they antibiotics will prevent a secondary bacterial infection (Wrong Practice!) Misdiagnose a viral infection for a bacterial infection (common cold vs. sinusitis)