Infectious Diseases Flashcards
measles
Notify department of health
– Take blood for measles serology-in Australia measles vaccine is given at the age of 12 months.
– Discuss the nasal swab PCR for measles with the department of health.
– Isolate her in the community from other contacts.
– There is no need to send the patient to the emergency department as it would risk the spread of measles to other susceptible patients in the hospital.
Zostavax
vaccine used to prevent herpes zoster infection
live attenuated vaccine
Zostavax contraindications
– Severely immunocompromised patients such as this patient who is on long term
steroids for his rheumatoid arthritis.
– Hematological malignancy.
– Recipients of haemopoietic stem cell transplantation.
-HIV infection and immunosuppression (below 15% CD4 lymphocytes).
Zostavax is a vaccine used to prevent shingles (herpes zoster) in older adults. However, it’s a live attenuated vaccine, meaning it contains a weakened form of the virus. Because it’s a live vaccine, there are certain groups of people for whom Zostavax is contraindicated, meaning they should not receive it.
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Severely Immunocompromised Patients:
- Why: These patients have weakened immune systems that can’t effectively control even the weakened virus in the vaccine. This includes people on long-term steroids (like the patient with rheumatoid arthritis), which suppress the immune system and make it risky to receive live vaccines. The weakened virus could potentially cause serious illness in these individuals.
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Hematological Malignancy (e.g., leukemia, lymphoma):
- Why: These cancers affect the blood and immune system, significantly impairing the body’s ability to fight infections. Receiving a live vaccine like Zostavax could lead to the reactivation of the virus, causing illness rather than preventing it.
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Recipients of Hematopoietic Stem Cell Transplantation:
- Why: After a stem cell transplant, the immune system is often extremely weakened and rebuilding. During this period, the body may not be able to handle a live vaccine, increasing the risk of complications from the vaccine itself.
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HIV Infection with Severe Immunosuppression (CD4 Count Below 15%):
- Why: In patients with HIV, especially when their CD4 count (a type of immune cell) is very low, their immune system is compromised. A CD4 count below 15% indicates severe immunosuppression, meaning the patient’s body would struggle to control the weakened virus in the vaccine. This could lead to an actual shingles infection, rather than protecting against it.
Zostavax is contraindicated in these groups because their weakened immune systems may not be able to handle the live virus in the vaccine. Instead of providing protection, it could potentially cause a serious infection.
Genital chlamydial infection
sexually transmitted
is commonly asymptomatic until severe salpingitis or urethritis occurs
common cause of infertility due to
tubal obstruction
cat scratch disease
- B.henselae from cats to humans through a contaminated
cat scratch wound or across a mucosal surface - Symptoms occurs 3 to 10 days after initial injury.
- papulopustular lesions at the bite site
- enlarged tender regional lymph nodes.
Axillary vein thrombosis
sportsmen
after strenuous exercise like wrestling.
oedema and redness
No tender lymphadenopathy
JE vaccination for shorter-term travellers, particularly if:
travel is during the wet season
travel may be repeated
the person will spend a lot of time outdoors
the person’s accommodation has no air-conditioning, screens or bed nets
Typhoid vaccine may be recommended for travellers ≥2 years of age travelling to
endemic regions, including:
the Indian subcontinent
most Southeast Asian countries
several South Pacific nations, including Papua New Guinea
cholera vaccine
Most travellers do not need
not officially recommended by WHO
if the traveller has never received a dose of traveller has never received a dose of dTpa.
offer dTpa vaccine
if the last dose was more than 10 years ago
Tetanus
Adults are recommended to receive a booster dose of tetanus-containing vaccine
Fever with rigors and chills
Biliary sepsis, lymphoma, pyelonephritis and pneumococcal pneumonia
Thailand + fever + rash + joint pain + low platelets + low WBC
Dengue fever
Dengue fever treatment
Suppurative treatment
Zika virus
microcephaly
- SEEN IN BABIES
Symptoms: • Many people infected with Zika virus are asymptomatic. • When symptoms do occur, they are generally mild and include fever, rash, conjunctivitis, muscle and joint pain, headache, and malaise. • Symptoms typically last for 2-7 days. 3. Complications: • Microcephaly: Zika virus infection during pregnancy can cause severe birth defects, including microcephaly, where babies are born with smaller heads due to abnormal brain development. • Guillain-Barré Syndrome: There is also an association between Zika virus and Guillain-Barré syndrome, a rare condition where the immune system attacks the nerves. 4. Diagnosis: • Diagnosed through laboratory tests like RT-PCR (Reverse Transcriptase Polymerase Chain Reaction) or serological tests to detect Zika virus RNA or antibodies.
shingles (herpes zoster infection)
- within 72 hours= famciclovir or acyclovir for
7-10 days after taking the viral swab.
after 72 hours since the onset of rash= no
benefit with antiviral treatment.
key serological feature of hepatitis D
Anti-LKM3 (liver, kidney microsomes)
autoimmune hepatitis.
anti-LKM1
outcome of liver transplantation
chronic hepatitis D is better than that for
chronic hepatitis B
When comparing the outcomes of liver transplantation for chronic hepatitis D versus chronic hepatitis B, the key point is:
- Hepatitis D: Patients with chronic hepatitis D generally have better outcomes after liver transplantation compared to those with chronic hepatitis B. This means they tend to have fewer complications and a higher chance of long-term survival.
- Hepatitis B: Although liver transplantation can be life-saving, patients with chronic hepatitis B are more likely to experience complications after the transplant, such as a recurrence of the virus in the new liver, which can affect their overall outcome.
In simple terms, liver transplant patients with chronic hepatitis D usually do better in the long run than those with chronic hepatitis B.
Chronic hepatitis D infection
increases the severity and progression of chronic hepatitis
if HDV infection occurs in acute hepatitis B
Chronic hepatitis D infection is unlikely
malaria incubation period
malaria prevention
- Doxycycline 100mg daily one day before the trip and continuing for four
weeks after leaving malaria zone. - Atovaquone/proguanil 250mg/100mg tablet started 1-2 days before travel and continued for
seven days after leaving malaria area
clinical diagnosis of herpes zoster infection
- maxillary nerve of the trigeminal nerve in this patient with a rash without an eruption.
Severe unilateral facial pain may be the first symptom of acute herpes zoster (shingles) and precedes the skin rash by a few days
Trigeminal neuralgia
sudden, brief and very severe paroxysms of
pain on one side of the face, in the distribution of one or more branches of the
trigeminal) nerve.
Definitive diagnosis of N. gonorrhoea infection
nucleic-acid amplification testing of a urethral or urine sample
Appropriate therapy for gonococcal urethritis
single dose of ceftriaxone 250 mg
intramuscularly plus a single dose of azithromycin 1 gram orally
Treatment of Chlamydia
- Single dose of 1-gram Azithromycin or Doxycycline for
seven days. - Should not have sex until at least a week has passed after the treatment.
- notifiable disease
Post-exposure prophylaxis for hepatitis B (hepatitis B vaccine and immunoglobulins)
recommended
– The exposed person has been vaccinated in the past and the post-vaccination antiHBs level is below 10 mIU/ml.
– Un-vaccinated exposed individuals.
– Unknown vaccination status of the exposed person.
previously vaccinated persons exposed + response to previous vaccination is unknown
the anti-HBs level should be
determined as quickly as possible
previously vaccinated persons exposed+
protective response anti-HBs level =10
mIU/mL at any time after previous vaccination
post-exposure prophylaxis is
not necessary
Live attenuated zoster vaccine is contraindicated in persons
– Chemotherapy.
– Radiation therapy.
– Oral corticosteroids (asthma, COPD, etc)
– Disease-modifying anti-rheumatic drugs (DMARDs).
– Malignant conditions of the reticuloendothelial system (such as lymphoma, leukaemia, Hodgkin’s disease).
– AIDS or symptomatic HIV infection.
positive HBsAg
positive HBcAb (IgM)
Acute infection
HBeAg positive
high infectivity in recent infection
influenza vaccine
- Protection for the mother and the
newborn baby for the first six months after birth - free to all pregnant woman in Australia.
- recommended for all pregnant women regardless of
gestation. - recommended for a woman planning a pregnancy.
- An unvaccinated pregnant woman should be immunised at any time during influenza season
unsafe sex + for HIV checkup
wait for 12 weeks before a test can
reliably confirm or rule out HIV infection
Contraindications for administering
pertussis-containing vaccinations
- severe allergic reaction to the vaccine (or
to one of its components) - encephalopathy not due to any other cause within 7
days of a prior vaccination. - Uncontrolled neurological disorders should prompt a
delay of the vaccination until the condition has been sufficiently assessed
Post sexual assault victim + STI prophylaxis
ceftriaxone 250 mg intramuscular as a single dose,
azithromycin 1 gram as a single dose and metronidazole 2 gram as a single
dose
to cover gonorrhoea, chlamydia species
and trichomonas vaginalis
most commonly seen symptom in botulism
Dysarthria
needle stick injury + exposure to an HIV positive person
PEP is recommended. ASAP
PEP should not be offered more than 72
hours after exposure.
health care worker should have
follow-up HIV-antibody testing at baseline, 6 weeks,
3months up to 6 months
