Respiratory Infections

1. Respiratory Infections Mrs. AmanyNiazy

2. Respiratory Infections Worldwide , an estimated 3 to 5 million children die annually as a result of acute respiratory disease. Upper respiratory tract infectionsaremore common than the lower respiratory tract infections.

3. Respiratory Tract

4. Respiratory Infections • Respiratory tract can be divided into: • Upper Respiratory Tract (URT): • Sinuses • Nasopharynx,. • Oropharynx. • Epiglottis • Larynx (voice cord) • Lower Respiratory Tract (LRT): • Trachea. • Bronchial tubes. • Alveoli. • Lungs.

5. Upper Respiratory Tract InfectionDefinitions • Sinusitis: Inflammation of the lining of the sinuses. • Pharyngitis: Inflammation of the mucous membrane and underlying tissue of the pharynx. Commonly referred to as “sore throat”. • Epiglottitis: Inflammation of the epiglottis, may cause respiratory obstruction, especially in children. • Laryngitis: Inflammation of the mucous membrane of the larynx “voicebox”.

6. Viral Infections of the URT • It is called common cold or acuteviral rhinitis. • Most of upper respiratory infections are caused by viruses (about 80%). • Although hundreds of kinds of viruses can cause common cold , the range of symptoms they produce is similar. • Most common in fall, winter and spring. • On average, most people have one to six colds annually. • They generally subside without any treatment. • Their major importance to health is that they damage respiratory tract defenses and thus give way to more serious bacterial disease.

7. Viral Infections of the URT • Symptoms: • Colds generally begin with malaise, sore throat, rhinitis, cough and hoarseness. • Symptoms are mostly gone within a week, but a mild cough sometimes continues for longer periods of time. • Secondary bacterial infection may follow (eg. Sinusitis & otitismedia) Rhinitis Most common symptom of common cold. Characterized inflammatory edema of the nasal mucosa, and in increase in mucous secretions with result in various degrees of nasal obstruction.

8. Viral Infections of the URT • Etiologic Agent: • Most common Rhinoviruses ( > 100 different types) • Coronaviruses. • Parainfluenza viruses. • Influenza viruses. • Adenoviruses. • Transmission: • Inhalation of airborne droplets containing the virus. • Virus-containing secretions are rubbed into eyes or nose by contaminated hands. A person with severe symptoms is more likely to transmit the viruses than those with mild or who is in the late stage of the cold.

9. Bacterial Infections of the URT • A number of different species of bacteria can cause URT, but generally do not require treatment cause the bacteria are eliminated by the immune system. • Some bacteria are not easily eliminated by the immune system and can cause serious complications like: • Corynebacteriumdiphtheriae Diphtheria • Strptococcuspyogenes.  Streptococcus pharyngitis or strep throat.

10. Bacterial Infections of the URTDiphtheria • Etiologic Agent: • Corynebacteriumdiphtheriae. • The bacteria release diphtheria toxin. • Symptoms: • Clotted blood, dead epithelial cells of host mucous membrane and white blood cells form a white-gray psudomembrane on the throat. • This membrane may come loose and obstruct the airways, causing the patient to suffocate. • Entry of toxin in blood stream can result in damage to heart, nerves, and kidneys.

11. Bacterial Infections of the URTDiphtheria • Transmission: • Typically organism is acquired by inhalation. • Disease is effectively controlled by immunization with the toxoid (DPT vaccine). • Unfortunately, Diphtheria continues to be a major killer of children in developing countries where the vaccine is not given.

12. Bacterial Infections of the URTStreptococcal Pharyngitis (=Strep Throat) • Etiologic Agent: • Streptococcus pygeneswhich is commonly referred to as group A streptococcus.

13. Bacterial Infections of the URTStreptococcal Pharyngitis (=Strep Throat) • Symptoms: • Pain (sore throat), difficulty swallowing, and fever. • Throat is red with white patches of pus. • Enlarged tonsils • Enlarged lymph nodes in the neck. • Most patients recover spontaneously after about a week.

14. White pus patches on pharynx; enlarged tonsils

15. Enlarged Lymph Node

17. Bacterial Infections of the URTStreptococcal Pharyngitis (=Strep Throat) • Transmission: • It spread readily by respiratory droplets by yelling, coughing, and sneezing (range of 0.5 – 1.5m). • A person maybe asymptomatic carrier and spread the infection.

18. Bacterial Infections of the URTStreptococcal Pharyngitis (=Strep Throat) • Group A Streptococcus or Streptococcus paygenesinfections may have serious complications. • These complications are uncommon but they are serious and can be deadly when overlooked. • Scarlet fever. • Acute glomerulonephritis. • Acute rheumatic fever.

19. Bacterial Infections of the URTStreptococcal Pharyngitis (=Strep Throat) • Scarlet Fever: • Most common in children age 4 to 8 • Red rash • Tongue look like surface of a ripe strawberry.

20. Bacterial Infections of the URTStreptococcal Pharyngitis (=Strep Throat) • Acute glomerulonephritis: • Usually began 10 days after the infection. • Many immune complexes deposit in the glomeruli and provoke an inflammatory reaction. • It starts with fever, fluid retention, high blood pressure, and protein in urine. • Only some strains of the bacteria can cause this condition.

21. Bacterial Infections of the URTStreptococcal Pharyngitis (=Strep Throat) • Acute rheumatic fever: • Begins about 3 weeks after recovery. • Fever, joint pain, chest pain , rash. • Acute behavioral changes and uncontrollable movement of different parts of the body. • Symptoms due to inflammatory process in different tissues especially joint, heart, skin and brain. • Heart failure and death may occur. • The risk of developing acute rheumatic fever after severe, untreated streptococcal pharyngitis is 3% or less.

22. Some strains of S.pyogenes: • Have strong exotoxin that cause necrosis to tissue, and it is called “flesh-eating bacteria”. • It can cause necrotizing fasciitis (destruction of flesh and muscle) • usually the bacteria inter skin through cut or wound. • doctors often must remove skin, large groups of muscle, or entire limbs to save a person’s life. • Afflicts 1 in every 489,000 people • >200,000 cases/year in the US

23. Lower Respiratory Tract InfectionDefinitions • Bronchitis: • Inflammation of the mucous membrane lining of the bronchial tubes. • Pneumonia: • Inflammation of one or both lungs. alveolar sacs become filled with exudate, inflammatory cells, and fibrin. • Bronchopneumonia: • Combination of bronchitis and pneumonia.

24. Lower Respiratory Tract (LRT) Infection • Viral Infections of the LRT: • Viral Respiratory Disease. • Avian Influenza (Bird Flu) • Influenza (Flu) • Sever Acute Respiratory Syndrome (SARS) • Hantavirus Pulmonary Syndrome (HPS)

25. Lower Respiratory Tract (LRT) Infection • Bacterial Infections of the LRT: • Legionnaire’s Disease (Pontiac Fever) • Pneumonia. • Tuberculosis (TB). • Whopping Cough. • Fungal Infections of the LRT: • Pneumocystis pneumonia (PCP).

26. Lower Respiratory Tract (LRT) InfectionPneumonia • Pneumonia: • It is inflammatory disease of the lung in which fluid fills the alveoli. • It can be typical or atypical • It can be community acquired or hospital acquired (nosocomial). • Can be caused by different microorganisms. • It is often a secondary infection that follows a primary viral respiratory infection. • It is common , around 40,000 to 70,000 people die every year in the USA

27. Lower Respiratory Tract (LRT) InfectionPneumonia • Symptoms: • Productive cough (=with sputum). • Acute chest pain. • Chills. • Fever. • Shortness of breath. • Clinically patient present with abnormal chest sounds and X-ray. • Etiologic Agent: • Gram-positive organisms (e.g. S.pneumoniae, Staphylococcus) • Gram-negative organisms (eg. Haemophilusinfluenzae, Klebsiellapneumoniae) • Legionella • Mycoplasma • Chlamydia.

28. Lower Respiratory Tract (LRT) InfectionPneumonia • Transmission: • Transmission depends on the pathogen involved. • It is by droplet inhalation. • Direct oral contact. • Contact with contaminated hands. • Inhalation of yeasts or fungal spores.

29. Lower Respiratory Tract (LRT) InfectionTypical VS Atypical Pneumonia • Typical pneumonia: • Etiologic agent is virulent bacteria (eg. S.pneumoniae). • Sudden onset. • Productive cough with purulent sputum. • Pleuritic chest pain. • Leukocytosis (high no. of WBC’s) or leukopenia (low no. of WBC’s) • Atypical pneumonia: • Etiologic agent is viruses or Mycoplasma pneumonia. • Gradual onset • Nonproductive cough.

30. Lower Respiratory Tract (LRT) InfectionCommunity Acquired Pneumonia Most common etiologic agent of community pneumonia is Streptococcus pneumoniae. It is a gram positive diplococci. The thick polysaccharide capsule is responsible for the organism’s virulence.

31. Lower Respiratory Tract (LRT) InfectionHospital Acquired Pneumonia It account for 15% of hospital acquired infections. It is the most common fatal hospital acquired infection (mortality rate 20-50%). People at risk are the immunocompromised patients. Most often caused by a resistant gram negative organism such as: Klebsiella, Pseudomonas aeruginosa, Enterobacger sp.

32. Lower Respiratory Tract (LRT) InfectionInfluenza (Flu) Influenza is an acute viral respiratory infection. • Symptoms: • Average 2 days incubation period. • Headache. • Fever. • Muscle pain. • Dry cough that can last for long time. • Nausea, vomiting, and diarrhea especially in children.

33. Lower Respiratory Tract (LRT) InfectionInfluenza (Flu) • Etiologic Agent: • Influenza virus A,B, and C. • Influenza A viruses: • Cause the most sever disease • It’s epidemics are the most widespread. • Have a great tendency to undergo significant antigenic changes. • Infect wide variety of species including mammals and birds. • Influenza B viruses: • Less sever disease. • More localized epidemics (=outbreaks). • More antigenically stable • Influenza C viruses: • Relatively with little importance.

34. Lower Respiratory Tract (LRT) InfectionInfluenza (Flu) • Carriers: • Human is the main carrier of virus but it also might be carried by birds and pigs. Pigs serve as “mixing bowls” for both avian and human strain resulting in new strains. • Transmission: • Airborne spread or direct contact.

35. Lower Respiratory Tract (LRT) InfectionFlu Vaccine • It is killed virus vaccine. • The best available method of control of influenza. • It is formulated each year to match the viral subtypes that is currently causing infections. • It is indicated for high-risk individuals: • Travelers. • Children 6 months – 5 years. • Elderly > 65. • Residents of nursing homes. • People with long term-illnesses (e.g. heart/lung) • People with depressed immunity. • Pregnant women in 2nd-3rd trimester. • Healthcare workers. • EVERYONE in the face of a Pandemic-threat.

36. Structure of Influenza A Virus Haemaglutinin (H) Neuraminidase (N) Viral RNA Antigenic DRIFT causes yearly epidemics. Antigenic SHIFT causes influenza pandemic (every 10-40 years).

37. Flu Pandemics • 1918-1919 Spanish flu: also known as the swine flu epidemic which killed 20-50 million people worldwide. • 1957-1958 Asian flu killed about 1 million people. • 1968-1969 Hong Kong flu killed about 0.7 million people.

38. Swine Flu H1N1 Outbreak- 2009 • April 4: 1st case in Mexico. • April 12: First death. • April 21-23: US confirms first 4 cases. • April 26: Canada confirms first cases. • April 27: Europe, Spain & Britain. WHO raises pandemic alert status to phase 4. • April 28: New Zealand & Israel. • April 29-30: Germany, Austria, Switzerland, Netherlands. • May 1: Hong Kong, Denmark, France. • May 2: South Korea, Italy.

41. Routes of Exposure to Spread the Infection • Primary Exposure Route: Person to Person • Inhalation of Airborne Droplets from Infected Person Coughing or Sneezing. • Secondary Route of Exposure: Viruses on Surfaces • Can Live on Surfaces for 2 Hours or More. • Person Touching Contaminated Tables, Doorknobs, Desks, Then Touching Face, Eyes, Nose, or Mouth.

43. Does Influenza Vaccine Protect from H1N1?? In the PAST: It does NOT protect against H1N1. NOW: It protect against H1N1 as they integrated it in the Influenza vaccine.

44. Treatment for Influenza H1N1

45. Prevention • Cough/Sneeze - Cover Nose/Mouth with Tissue or Sneeze into the Sleeve. “Dispose Used Tissues in the Trash”. • Wash Hand with Soap & Water (At Least 20 Seconds) or Use Alcohol-Based Hand Sanitizers. • Avoid Touching Eyes, Nose, or Mouth. • Avoid Contact with Sick People. “If Sick, Stay at Home Away from Work or School and Limit Contact with Others”.