11. Vaccine Preventable Diseases.pdf

7/8/2023 Vaccine Preventable Diseases • Tuberculosis • Hepatitis B • Diphtheria • Tetanus • Pertussis • Poliomyelitis • Haemophilus influenzae type b Vaccine Preventable Infections 1 • Pneumococcus • Measles • Mumps • Rubella • Human papilloma virus • Japanese B encephalitis 2 Tuberculosis Tu...

7/8/2023 Vaccine Preventable Diseases • Tuberculosis • Hepatitis B • Diphtheria • Tetanus • Pertussis • Poliomyelitis • Haemophilus influenzae type b Vaccine Preventable Infections 1 • Pneumococcus • Measles • Mumps • Rubella • Human papilloma virus • Japanese B encephalitis 2 Tuberculosis Tuberculosis • Transmission: respiratory droplets • Incubation period: 2–10 weeks TB disease Latent TB infection Acid Fast bacilli Asymptomatic Pulmonary TB Lymphadenopathy Meningitis Mycobacterium tuberculosis Ziehl-Neelsen stain Miliary disease Pleural disease Skeletal infection 3 5 Pulmonary Tuberculosis Bacille Calmette-Guérin (BCG) • Attenuated strain of Mycobacterium bovis • Duration of immunity 10-15 years • Intradermal in deltoid area of left arm Tuberculous Pleural Effusion 6 Miliary TB 8 1 7/8/2023 Normal Reaction after BCG BCG Efficacy Active TB disease 2-4 weeks Disseminated TB & meningitis ~50% (range 0 to 80%) 6-8 weeks Bump softens, oozes pus, then crust 2-4 months 70 to 80% Painless red, raised bump Sore heals & leaves a scar 9 11 Diphtheria BCG Adverse Reactions • Transmission: respiratory droplets; contact with resp secretions or infected skin lesions • Exotoxin inhibits protein synthesis in cells Keloid Toxigenic strains of Corynebacterium diphtheriae Gram positive pleomorphic bacilli Suppurative Lymphadenitis Non-suppurative Lymphadenitis • Osteitis • Disseminated BCG infection 14 20 Diphtheria: Pathogenesis Pharyngeal diphtheria (Pharyngitis, Pseudomembrane, Fever, Lymphadenitis) Diphtheria: Clinical Manifestations Respiratory droplets Initial symptoms resemble viral URTI: malaise, sore throat and nasal discharge Toxin disseminate in blood URTI Neuropathy Myocarditis Touching infected open sores or ulcers Symptom Progression Severe Cases Cutaneous diphtheria 21 Bloody nasal discharge, hoarse voice, cough, and/or pain with swallowing Gross neck swelling, noisy breathing (inspiratory stridor) and shortness of breath, lethargy, shock 23 2 7/8/2023 Diphtheria Pseudomembrane Swollen neck or “bull neck” Dense, gray debris layer composed of a mixture of dead cells, fibrin, RBCs, WBCs, and organisms. Due to swollen cervical lymph nodes, soft tissue edema and mucosal edema 24 26 Pertussis Pertussis • Bordetella pertussis • Transmission: respiratory droplets Antigenic components: • Pertussis toxin (PT) Normal ciliary movement Ciliary Stasis • Filamentous hemagglutinin (FHA) • Aagglutinogens • Adenylate cyclase • Pertactin • Tracheal cytotoxin Ciliated Epithelium Bordetella pertussis Fastidious gram-negative bacilli 35 Bordetella pertussis bacterium Filamentous hemagglutinin Pertussis toxin 38 Pertussis: Stages of disease Catarrhal stage Duration 1 - 2 wk Paroxysmal stage Duration 1 - 6 wk Rhinorrhea Sneezing Low-grade fever Mild cough Paroxysmal cough Inspiratory whoop Post-tussive emesis 42 Pertussis Convalescent stage Cough subside over next 2 - 3 wks Paroxysmal cough recur with URI months after the initial infection 43 3 7/8/2023 Pertussis: Complications • Pneumonia Tetanus • Spores found in soil, animal feces • Transmission: direct contamination (wound, umbilical • Seizures • Apnoea/Bradycardia cord in newborn) • Produce exotoxins Clostridium tetani • Tetanolysin gram-positive, drumstick-shaped bacilli • Rib fracture (local tissue necrosis) • Encephalopathy • Tetanospasmin (neurotoxin) • Otitis media 44 50 Tetanus Tetanus: Manifestations Trimus (Risus sardonicus) • Generalized tetanus • Spasm of the muscles of jaw (lockjaw) • Painful spasms in other muscle neck, trunk, and extremities • Generalized, seizure-like activity or convulsions Opisthotonus (backward arching of the head, neck, & spine) • Localized tetanus: muscle spasms in a confined area close to the site of the injury • Cephalic tetanus: flaccid cranial nerve palsies • Autonomic instability: hypertension, tachycardia 51 53 Hepatitis B Tetanus: Complications • Laryngospasms • Fractures • Hypertension • Nosocomial infections • Pulmonary embolism • Aspiration pneumonia • Death Transmission: • Sexual contact • Sharing needles • Exposure to infected blood • Mother to newborn HBsAg HBcAg DNA Polymerase HBeAg HBV 40–42-nm enveloped DNA virus Virus enters liver via bloodstream 54 62 4 7/8/2023 Perinatal Transmission in Pregnant Women Hepatitis B: Clinical Manifestations Perinatal Transmission • Asymptomatic HBsAg +ve mother 0-72% • Acute hepatitis • Fulminant Hepatitis HBsAg & HBeAg +ve mother 70-90% • Chronic hepatitis: HBsAg in blood >6 months Progression to severe liver disease (cirrhosis, liver failure, liver cancer) Highest for infection in the first year of life Give HBIG and HB vaccine within 12 hours after birth for infants born to HBsAg positive mothers 67 71 Hib Infections Haemophilus influenzae type b Infections • Transmission: respiratory droplets or direct contact with respiratory secretions • Pharyngeal colonization common Pleomorphic gramnegative coccobacillus in CSF Pneumonia Meningitis with subdural empyema 77 78 Hib Infections Acute epiglottitis Foot Cellulitis Peripheral gangrene Erythema & swelling of the epiglottis 79 Periorbital cellulitis 80 5 7/8/2023 Clinical Features of Poliovirus Infection Polio Virus • Asymptomatic (72%) • RNA virus • Serotypes: type 1, type 2, type 3 • Transmission: fecal-oral route (person-to-person) • Risk factors: Suboptimal hygiene, sanitation & poor water quality • Mainly affects children <5 years • Replicates in GI tract & motor neurons of the spinal cord (Paralysis) • Minor illness (24%): Fever and flu-like symptoms (malaise, drowsiness, headache, nausea, vomiting, sore throat) • Nonparalytic poliomyelitis (4%) Headaches, stiffness and pain in neck, back, limbs (Meningitis) • Paralytic poliomyelitis ( <1%) Flaccid-paralysis 87 88 Paralytic polio Paralytic Polio Iron Lung Rancho Los Amigos Hospital, California, 1952 89 90 Measles virus OPV versus IPV Attribute Occurrence of VAPP Systemic immunity Gastrointestinal Immunity Contact immunity from viruses shed by vaccine Ease of administration, storage & transport Compliance with immunization OPV IPV Yes No High (95%) High (>99%) High Yes Low No Easy Difficult High Reduced Combination vaccines No Yes Cost Low Higher 96 • RNA virus with 1 serotype • Transmission: respiratory droplets (person to person) • Highly transmissible: >95% immunity in population needed to stop transmission • Incubation period 10-14 days 106 6 Temperature C 7/8/2023 Fever Measles: Koplik Spots Measles 40 39 38 37 Rash Koplik Spots Conjunctivitis Coryza Cough 1 2 3 4 5 Incubation Prodrome Phase (8-12 d) 6 7 8 Rash 9 10 Convalescence 114 115 Measles Rash Measles: Complications • Otitis media • Pneumonia • Keratoconjunctivitis • Stomatitis • Croup • Central nervous system • Encephalitis • Subacute sclerosing panencephalitis (SSPE) 116 121 Mumps Virus Mumps • RNA virus • Transmission: respiratory droplets, direct contact, or contaminated fomites • Incubation period: 12 to 25 days • Replicate in parotid gland ductal epithelium, causing interstitial oedema, local inflammation, and painful swelling of the gland 124 125 7 7/8/2023 Rubella Virus Mumps: Extra-salivary gland manifestation • RNA virus • Epididymo-orchitis • Oophoritis • Pancreatitis • Arthritis and arthralgias • Myocarditis • Aseptic meningitis • Encephalitis • Transmission: respiratory droplets (person-to-person) • Incubation period: 14 days • Replicates in the nasopharynx and local lymph nodes and then spreads hematogenously throughout the body 126 128 Rubella: Clinical Manifestations Rubella: Clinical manifestations • Lymphadenopathy: • Usually a mild, selflimited illness • Prodromal illness: low fever (< 39C), malaise and mild conjunctivitis Postauricular, occipital & posterior cervical • Maculopapular, itchy rash Photo: CDC • Arthritis, arthralgia • Post-infectious encephalitis Photo: CDC (rare) 130 131 Congenital Rubella Syndrome Cataracts Pneumococcal Infection • Transmission: respiratory • Infection during 1st trimester in pregnant woman (embryogenesis) droplets (person to person) • Nasopharyngeal carriage • Clinical features • • • • 133 Microcephaly Congenital heart defects Sensorineural deafness Developmental delay rates in children 21% to 90% • 10–15 serotypes cause majority of invasive disease Streptococcus pneumoniae Gram-positive diplococci Hepatosplenomegaly & 'blueberry muffin' skin 151 8 7/8/2023 Pneumococcal disease Noninvasive • Otitis media • Sinusitis • Periorbital cellulitis • Mastoiditis • Conjunctivitis Pneumococcal Infection Invasive • Meningitis • Pneumonia • Septicaemia • Osteomyelitis/Septic Arthritis Acute mastoiditis 154 Perionychial abscess 159 Pneumococcal Infection Human Papillomavirus • Double-stranded DNA virus • Transmission: skin-to-skin contact, facilitated by minor skin trauma • Incubation period: 3 months to several years • About 14 high-risk HPV types • HPV16 & HPV18 responsible for most HPV-related Left upper lobe pneumonia Pneumococcal pneumonia with right pleural effusion 160 cancers 165 HPV: Clinical Manifestations Natural Outcome of HPV Genital Infection Transient infection Resolved infection 1-2 yrs HPV Infection Cutaneous Wart Perianal Wart 167 Genital Wart (Condyloma acuminata) >2 yrs Low High Persistent Invasive grade grade infection 0-1 yr Cancer 0-5 yrs Dysplasia Dysplasia 1-20 yrs 170 9 7/8/2023 JEV Transmission Cycle Japanese Encephalitis (JE) Vertebrate hosts Migratory birds & bats Pigs • Japanese encephalitis virus (JEV) RNA flavivirus • Incubation period: 5–15 days Vector Vector Culex mosquitoes Culex mosquitoes • Occurs mainly among children <15 years • <1% of people infected with JEV develop disease Vertebrate hosts Adults Pupae Larvae 182 Birds Deadend hosts Humans & Horses Eggs 184 Clinical Manifestations of JEV Infection • Undifferentiated febrile illness • Acute encephalitis • Aseptic meningitis 186 10