flu and respiratory tract infections Flashcards
what are the clinical presentations of influenza?
- fever
- malaise (generally unwell)
- myalgia (muscle pain)
- headache
- cough
- prostration (weakness)
what are the types of ‘flu’?
- classical; influenza A and B
- flu-like illnesses; parainfluenza viruses and many others
- haemophilus influenza; bacterium, not a primary cause of flu, may be secondary invader
how is influenza transmitted?
-droplets or through direct contact with respiratory secretions
when are infection control precautions used?
Intubation, extubation and related procedures, for example manual ventilation and open suctioning.
Cardiopulmonary resuscitation.
Bronchoscopy.
Surgery and post mortem procedures in which high-speed devices are used.
Dental procedures.
Non Invasive Ventilation (NIV) e.g. Bilevel Positive Airway Pressure Ventilation (BiPAP) and Continuous Positive Airway Pressure Ventilation (CPAP).
High Frequency Oscillatory Ventilation (HFOV).
Induction of sputum.
what are complications of ‘flu’?
- primary influenza pneumonia (pandemics, can be of young people, high mortality)
- secondary bacterial pneumonia (infants, elderly and debilitated, pre-existing disease and pregnant women)
- bronchitis
- otitis media (?)
- influenza during pregnancy may be associated with perinatal mortality, prematurity, smaller neonatal size and lower birth rate
what is the therapy for flu?
- treating symptoms e.g. bed rest, fluids, paracetemol
- antivirals - oseltamivir, zanamivir
- monitor for complications
why might pandemics occur?
-influenza A only
-antigenic shift
segmented genome
-animal reservoir/mixing vessel
how do we confirm influenza?
-PCR is done on; nasopharyngeal swabs, throat swabs or other respiratory samples
what are the types of flu vaccines?
- killed vaccine = grown in hens eggs or cell culture then inactivated and combine with an adjuvant, contains 2 influenza A viruses and one or two influenza B viruses, given annually to at risk groups.
- live attenuated vaccine = more effective in children aged 2-17, administered intra-nasally.
can antivirals be used as prophylaxis?
- yes but rarely done
- see NICE guidelines
which flu like virus is prevalent in the summer?
parainfluenza virus 1
what are common causes of community acquired pneumonia?
(microbiological causes)
- mycoplasma pneumonia
- coxiella burnetii
- chlamydia
Describe mycoplasma, coxiella and chlamydia psittaci
- all respond to tetracycline and macrolides (clarithromycin)
- generally lower mortality than classical bacterial pneumonia
- often referred to as atypical pneumonia
- confirmed by serology (sputum), and virus detection by PCR
Describe mycoplasma pneumonia.
- often community acquired
- children and young adults have highest incidences
- person to person spread
Describe coxiella burnetti.
- cause diseases such as pneumonia and pyrexia of unknown origin (Q fever)
- uncommon, sporadic zoonosis (?)
- from sheep and goats
- complications include culture negative endocarditis
Describe chlamydia and respiratory disease.
- chlamydophilia psittaci causes psittacosis (chlamydia psittaci)
- uncoomon, sporadic zoonosis
- caught from pet birds (parrots, budgies and cockatiels)
- usually presents as pneumonia
what are the clinical presentations of bronchiolitis?
- 1st or 2nd year of life
- fever, coryza (inflammation of mucus membrane in nose), cough, wheeze
- severe cases; grunting, decreased Pa02, intercostal/sternal indrawing
what complications can come form bronchiolitis and how is it controlled?
- respiratory and cardiac failure (due to prematurity or pre existing conditions)
- NICE and SIGN guidelines on treatment
- up to 80% caused by respiratory syncytial virus (RSV)
- epidemics every winter
- stop spread in hospital wards by cohort nursing, handwashing, gowns, gloves etc.
Describe metapneumonovirus.
- most children antibody positive by 5
- highest incidence in winter
- may be second only to RSV in bronchiolitis
- similar symptoms to RSV
- range of severity from mild to requiring ventilation
- confirmed by PCR
what are alternative types of chlamydia?
- chlamydia trachomatis = STI which can produce infantile pneumonia when carried in mother
- chlamydophilia pneumonia = person to person, mostly mild respiratory infections, may be picked up by psittascosis tests