immunisation and prophylaxis Flashcards
5 in 1 vaccine
D-purified diphtheria toxoid T- purified tetanus toxoid aP = purified boardetella pertussis IPV= inactivated polio virus Hib= purified
UK childhood immunisation schedule
2 months,3 months 4 months: 5in 1 vaccine+ pneumococcal conjugate +men B
- 1 year: Hib/Men C+ MMR + pneumococcal conjugate + men B
- 2, 3 and 4 years: influenza
- 3 - 5 years: 4-in-1 booster (DTaP/IPV) + MMR
- Girls, 12-13 yrs: Human papilloma virus
- 14 years: 3-in-1 booster (dT/IPV) + Men ACWY
influenza vaccine
• Indications: o o Age >65 years o Nursing home residents o Some health care workers o Immunodeficiency o Immunosuppression o Asplenia/hyposplenism o Chronic liver disease o Chronic renal disease o Chronic cardiac disease o Chronic lung disease o Diabetes mellitus o Coeliac disease o Pregnant women o Heath care workers •
pneumococcal vaccine
o Part of childhood immunisation schedule
o 3 doses
Hep B
Hep B vaccination:
• Children at high risk of exposure to HBV, and babies born to infected mothers
• Health care workers, PWID, MSM, prisoners, ch. liver disease, ch. kidney disease,
• Given at 0, 1 month,2 months and 1 year
varicella zoster
suppresed immune system
• Health case workers (if sero-neg and in contact with patients)
• Live attenuated virus
• 2 doses, 4-8 weeks apart
Adults who get chicken pox tend to develop pneumonitis which can be fatal
herpes zoster vaccine
all elderly patients
passive immunisation
• Human normal immunoglobulin
o contains antibodies against hepatitis A, rubella, measles
o used in immunoglobulin deficiencies
o treatment of some autoimmune disorders, e.g. myasthenia gravis
• Disease specific immunoglobulin
o hepatitis B Ig
o rabies Ig
o tetanus anti-toxin Ig
o varicella (chickenpox) Ig – can be used in pregnant women to provide instant protection
o diphtheria anti-toxin Ig (horse)
o botulinum anti-toxin Ig
common immunisations for travellers
tetanus polio tyhphoid hepatitis A yellow fever cholera
antimicrobial prophylaxis
o Chemoprophylaxis against Malaria
o Post-exposure prophylaxis
♣ e.g. ciprofloxacin for meningococcal disease
o HIV post-exposure prophylaxis
♣ “needle stick” (PEP), sexual intercourse (PEPSI)
Surgical antibiotic prophylaxis – perioperative
UK guidelines for malaria
Awareness of risk Bite prevention Chemoprophylaxis o Malarone ® (atovaquone & proquanil) daily o doxycycline daily ♣ Not for children <12 years ♣ photosensivity o mefloquine weekly ♣ Side effects: psychosis, nightmares (1:10,000) ♣ Avoid if history of psychosis, epilepsy o chloroquine weekly + proquanil daily ♣ For vivax/ovale/malariae only o Choice depends on country. • Diagnosis and treatment • Advice on return: Any illness occurring within 1 year and especially within 3 months of return might be malaria
symptoms of malaria
o fever o rigors o aching bones o abdo pain o headache o dysuria o sore throat o cough o hepatomegaly o Splenomegaly o Mild jaundice
complications
cerebral malaria o Blackwater fever severe intravascular haemolysis, high parasitaemia, profound anaemia, haemoglobinuria (black urine), acute renal failure (or pH < 7.3) o Pulmonary oedema or ARDS o Jaundice o Severe anaemia
diagnosis
high clinical suspicion thick & thin blood films- giemsa, field's stain quantitative buffy coat -centrifugation, UV microscopy rapid antigen tests
treatment
o Uncomplicated P. falciparum malaria
♣ Riamet ® (artemether-lumefantrine) 3 days
• First line
♣ Eurartesim ® (dihydroartemisinin-piperaquine) 3 days
♣ Malarone ® (atovaquone-proguanil) 3 days
♣ Quinine 7 days (plus oral doxycycline or clindamycin)
• S/E nausea, tinnitus, deafness (cinchonism), rash, hypoglycaemia
Quinine is generally difficult to tolerate
o Severe or complicated P. falciparum malaria
♣ IV artesunate (unlicensed in UK)
♣ IV quinine (plus oral doxycycline or clindamycin)
• (S/E cardiac depression, cerebral irritation, N&V)
♣ When patient is stable & able to swallow, switch to oral treatments
o Treatment of P. vivax, P. ovale, P. malariae, P. knowlesi
♣ chloroquine 3 days
♣ Riamet ® (artemether-lumefantrine) 3 days
♣ Add primaquine (14 days) in vivax and ovale, to eradicate liver hypnozoites
• Prevent recurrence by latent malaria in liver
• Check for G6PD deficiency
G6PD deficiency leads to haemolysis in patients whenever they are exposed to oxidative stress in the form of drugs
typhoid (enteric)
• Caused by: Salmonella typhi, salmonella paratyphi
o poor sanitation, unclean drinking water
• Clinical features:
o Incubation period: 7 days - 4 week
o 1st week:
♣ fever, headache, abdo. discomfort, constipation, dry cough, relative bradycardia, neutrophilia, confusion
o 2nd week:
♣ fever peaks at 7-10 days, Rose spots, diarrhoea begins, tachycardia, neutropenia
o 3rd week (Complications):
♣ intestinal bleeding, perforation, peritonism, metastatic infections
o 4th week (Recovery):
♣ 10 - 15% relapse
Diagnoses
clinical: evolution of features
lab tests: blood culture, urine, stool
bone marrow culture
treatment
o Oral Azithromycin
♣ now drug of choice for Asian-acquired, uncomplicated enteric fever
o IV Ceftriaxone
if complicated
Dengue fever
• Classic dengue fever symptoms o Sudden fever o Severe headache, retro-orbital pain o Severe myalgia and arthralgia o Macular/ maculopapular rash o Haemorrhagic signs: petechiae, purpura, positive tourniquet test (due to fragile skin and vessels)
diagnosis
clinical ♣ Thrombocytopenia ♣ Leucopenia ♣ Elevated transaminases ♣ Positive tourniquet test o Laboratory: ♣ PCR, serology
Management
no specific therapeutic agents
shistosomiasis
spread via fresh water snails
• Clinical features:
o Swimmers Itch (1st few hrs)
♣ clears 24-48hrs
o Invasive stage (after 24hrs)
♣ cough, abdo discomfort, splenomegaly, eosinophilia
o Katayama Fever (after 15-20 days)
♣ prostrate, fever, urticaria, lymphadenopathy, splenomegaly, diarrhoea, eosinophilia
o Acute disease (6-8 weeks)
♣ eggs deposited in bowel (dysentery) or bladder (haematuria)
Chronic disease
diagnosis
o Clinical diagnosis
o Antibody tests
♣ It usually takes 4-8 weeks for seroconversion to occur, although it can be up to 22 weeks and serology remains positive for two years after eradication. (not useful to differentiate past illness)
o Microscopy for ova in stools and urine
o Rectal snip - When it is necessary to obtain a rapid diagnosis of schistosomiasis, or if screening tests have been inconclusive.
treatment
o PRAZIQUANTEL
o Prednisolone if severe
rickettsiosis
group of dieases species of Rickettsia classified into two main groups: 1. the spotted fever group, transmitted by ticks or mites 2. typhus group, mainly transmitted by lice or fleas. Examples: • Tick typhus (R. conorii, R. africae) o Maculopapular rash o Commonest, imported to UK • Rocky Mountain Spotted Fever (R. rickettsii) • Epidemic typhus (R. prowazekii) o Vector: lice o Mortality up to 40%
clinical features
abrupt onset of swinging fever, headache, confusion,endovasculitis, rash (macular, petechial)
diagnosis and management
• Diagnosis: o Clinical diagnosis & response to treatment o Serology or PCR • Management: o Tetracycline or doxycycline
Viral haemorrhagic fevers
• Serious infections (but rare in UK): o Ebola o Congo-Crimea haemorrhagic fever o Lassa fever o Marburg disease • Maximum incubation period 3 weeks • Isolation: High Security Infection Unit Treatment: supportive
Zika
• sexual contact, blood transfusion
• Related to dengue, yellow fever, Jap B encephalitis and West Nile viruses
• Clinical features:
o None or mild symptoms - headache, rash, fever, malaise, conjunctivitis, joint pains (like dengue)
o In pregnancy, can cause microcephaly and other neurological problems
o Can cause Guillain-Barre syndrome
Approach to returning traveler
History: is it tropical travel history precautions taken risks symptoms incubation period
examination
rash-typhoid, tyhus, dengue
jaundice- hepatitis, malaria, yellow fever
lymph nodes-leishmania, schistosomiasis, trypanosomiasis
liver- malaria, typhoid, amoebic abscess
spleen- visceral leishmaniasis, typhoid, malaria
Investigation
• FBC • malaria films • liver function tests • stool microscopy & culture • urine analysis & culture • blood culture(s) • CXR • Special tests as indicated o dengue o respiratory viral/atypical o hepatitis A, B, C o tick typhus (Rickettsia) o schistosomiasis o amoebic o leptospirosis/hantavirus o viral haemorrhagic fevers
Treatment • Isolation o personal protective equipment • Supportive measures (resuscitation) • Empirical treatment if patient unwell o Antimicrobial therapy based on likely diagnosis o aim to treat life-threatening conditions e.g. typhoid, septicaemia Specific treatment once diagnosis
