1. Epidemiology and Prevention of Airborne Diseases
Dr. MUSTAQUE AHMED
MBBS,MD(COMM MEDICINE),FELLOWSHIP

2. Learning objectives Discuss about upper respiratory infections
Discuss about the influenza and SARS.
Describe the prevention of respiratory tract infections and SARS.

3. Anatomy of Respiratory Tract
The upper respiratory tract includes the sinuses, nasal passages, pharynx, and larynx.
An upper respiratory tract infection, is an infectious process of any of the components of the upper airway.

4. Terminology for Upper Respiratory Tract Infection
Infection of the specific areas of the upper respiratory tract can be named specifically.
Rhinitis -inflammation of the nasal cavity mucosa.
Sinusitis or rhinosinusitis - inflammation of the paranasal sinuses
Common cold (nasopharyngitis) - inflammation of the nares, pharynx,
Pharyngitis -inflammation of the pharynx, uvula, and tonsils,
Epiglottitis -inflammation of the epiglottis,
Laryngitis-inflammation of the larynx.

5. AGENT FACTORS VIRUS Rhino viruses (30-80%) All ages Common cold
Corona virus (15%)
Influenza – A ,B,C
Fever, aching, malaise
Para influenza - 1 ,2,3
Young children
Croup, mildURTI
Adeno viruses
Young children,  Adults
Influenza like illness
R.S.V (respiratory syncytial virus)
Infants+Children
Severe broncholitis and pneumonia
MEASLES
Fever, coryza, cough&rash
Ebstein-Barr virus
children
Pharyngitis ,tonsilitis
AGENT
Age group
CLINICAL FEATURE
BACTERIA
Strepto cocus pyogenes (Group.A)
All ages
Acute pharyngitis and Tonsillitis
Hemophilus influenzae
Adults + children
Acute epiglottitis,
Coryne bacterium diphtheriae
Children.
Nasal/Tonsilar/pharyngeal membranous exudate
Bordetella pertusis
Infants, young children
Paroxysmal cough

6. RISK FACTORS Many risk factors of RTI have been identified.
Housing-close contact with children in a group setting, schools or daycare centers;
Over crowding - such as, traveling, tours.
Indoor smoke pollution -cigarette smoking (impair mucosal resistance and destroy the cilia);
Climate -COLD
Level of industrialization
Nutrition – more in malnourished children.
Health care facilities.
Anatomical abnormalities as in nasal polyps.

7. TRANSMISSION OF RESPIRATORY TRACT INFECTIONS
Through the air. can spread from person to person by inhaling respiratory droplets from coughing or sneezing.
Direct contact. The transmission can also occur by touching the nose or mouth by hand or other object exposed to the virus. such as toys, any surface that have been previously touched by someone with a cold.

8. What is influenza (“the flu”)?
Respiratory Disease caused by a virus.More severe than a cold
10%-20% of US residents will get the flu each year (CDC)
Types of influenza virus
Causative agent: Orthomyxovirus, 3 types:A,B C.
Influenza A
Most common of outbreaks /most serious
Can lead to most serious forms of epidemics/pandemics
Currently circulating influenza virus in world
H1N1(TypeA)-cause of swineflu
H5N1(TypeA)- cause of avian flu(bird flu)
Influenza B
Symptoms are milder
Influenza C
Never connected with large epidemics

9. URI, influenza: symptom comparison
Symptoms
URI
Influenza
Itchy, watery eyes
Rare (conjunctivitis may occur with adenovirus)
Soreness behind eyes, sometimes conjunctivitis
Nasal discharge
Common
Nasal congestion
Sometimes
Sneezing
Very common
Sore throat
Cough
Common (mild to moderate, hacking)
Common (dry cough, can be severe)
Headache
Rare
Fever
Rare in adults, possible in children
Very common (  °F (or higher in young children), lasting 3–4 days; may have chills)
Malaise
Fatigue, weakness
Very common, can last for weeks, extreme exhaustion early in course
Muscle pain
Slight
Very common, often severe

10. Vaccine- The Flu Shot Protecting yourself
Inactivated(killed) influenza vaccines and recombinant influenza vaccines
Administered yearly
Injection or nasal spray (FluMist)
Can prevent types A and B
Protecting yourself
Get flu shot
Use proper PPE around patients suspected of having the flu
Clean and Disinfect surfaces regularly
Get enough rest
Eat well

11. Avian Influenza Symptoms
February 2004: 72,000 chickens were slaughtered in Delaware after two cases of Avian Influenza were found at a poultry farm under contract for Perdue Farms, Inc.
Symptoms
Same as typical flu-like symptoms
Conjunctivitis
Pneumonia
Severe respiratory distress

12. Incidents of H5 Avian Influenza
1997: Hong Kong- First documented transmission of birds to humans
18 people hospitalized
6 died
1.5 million chickens slaughtered to prevent further spread of disease
Transmission
Contact with infected poultry or contaminated surfaces
No documented cases of sustained human to human transmission
Monitoring is important
Influenza viruses have the ability to change
May gain the ability to spread from person to person
PREVENTION- USE OF PPE

13. SARS- Severe Acute Respiratory Syndrome
Severe acute respiratory syndrome (SARS) is a respiratory disease in humans, in which the lungs inflamate and there is difficulty in breathing, which is caused by the coronavirus.
Declared as a “worldwide health threat.”
1st new disease of 21st century

14. Epidemiology of SARS-1st CASE
The 1st case was traced to a health care worker in China, in NOV 2002.
SARS known only from February 2003.
Spread from China to North America, South America, Europe and other parts of Asia. By August 2003, about 8422 cases were reported to the WHO from 30 countries with 916 fatalities.
Dr.Carlo Urbani(Italian physician) identified this epidemic and carried out initial steps to prevent this epidemic.

16. Causes of SARS-Pathogen(CORONA VIRUS)
Infectious Agent = Severe Acute Respiratory Virus
Newly discovered coronavirus
Coronavirus = group of viruses that have a halo/crown-like appearance 
Causes mild to moderate upper respiratory illness in humans or respiratory, gastrointestinal, liver, and neurologic diseases in animals 
Can usually survive in an environment upto 6hours.

17. Clinical Symptoms Fever, chills Malaise Dry cough Sore throat Myalagia
Headache
Running nose
Travel within 10 days to an area with suspected community transmission OR
Close contact within 10 days with a person with a respiratory illness or someone sick from SARS
Incubation period
The incubation period has been estimated to be 2 to 7 days, commonly 3 to 5 days

18. Complications MORTALITY RATE OF PATIENTS
Most people with SARS develop pneumonia. Breathing problems can become so severe that a mechanical respirator is required. SARS is fatal in some cases, often due to respiratory failure. Other possible complications include heart and liver failure.
People older than the age of 60 — especially those with underlying conditions such as diabetes or hepatitis — are at highest risk of serious complications.
MORTALITY RATE OF PATIENTS
Ages 24 and under: less than 1%
Ages 25-44: 6%
Ages 45-64: 15%
Over 65: 50%

19. Treatment No uniform treatment for SARS-CoV
Can easily be confused with other lung related illnesses so patients are usually given:
Broadspectrum antibiotics
Antiviral agents
Immunomodulatory therapy
Supportive care
Requires intensive care and observation

20. Why a Respirator Is Necessary-The N95 Respirator
Healthcare providers work in an environment where there is a risk of disease transmission through airborne infectious particulates.
The most common respirator used is the disposable particulate type N95.
The “N” stands for respirator filters that can be used when no oil is present in the contaminants.
The“95” means that the product has been tested and certified to have a filter efficiency level of 95% or greater against particulate aerosols.

21. PREVENTION OF UPPER RESPIRATORY TRACT INFECTIONS AND AIR BORNE DISEASES
Primary Measures- measures that can reduce the risk of infections in general.
stop Smoking, reducing stress, adequate and balanced diet, and regular exercise are all measures that can improve the immune system and reduce the overall risk of infections.
Secondary Measures- preventive measures to diminish the risk of spread of upper respiratory infections are:
Regular hand washing/hand hygiene is encouraged .
covering mouth and noise when coughing or sneezing;
reducing contact with people who may have the infection .
cleaning and disinfection of surface
THANK YOU