11. Travel Medicine Flashcards
Travel assessment
- 6-8 weeks prior to departure
- Purpose of travel
- Underlying health & vaccination status
Itinerary:
- Destinations
- Accommodation
- Planned activities
- Duration of travel
- Prior travel experience
Medical recommendations:
- Vaccines
- Prophylaxis
- Self-treatment
- Follow up (if required)
Risk factors
- Young
- Elderly
- Disabilities
- Pregnancy
- Immunocompromised
- Long term medical conditions
- High risk destinations
Managing medications
- Medical certificate
- Insurance
- Storage
- Managing time zones
High risk medications:
- Insulin
- Warfarin
- Contraception
- Controlled drugs
3 R’s
- Routine
- Required
- Recommended
Vector borne diseases: Insect avoidance
Personal protection:
- Wear light coloured clothing
- Use clothing that covers most of the body – long sleeves & pants
- Use insect repellent
- Use insecticide vaporisers
- Minimise use of perfumes, aftershave, soaps & body lotions
- Avoid outdoor activity during peak biting times
- Use bed net & clothing impregnated with insecticide
Vector borne diseases: Insect repellent
- DEET: \+ Most studied & long term use \+ Minimal ADRs \+ Concentration 20 – 50% \+ Effective for 4 – 8 hours - Picaridin - Oil of lemon eucalyptus
Application: - As per manufacturer instructions - Reapplication may be required more when often \+ Swimming \+ Concurrent use of sunscreen
Malaria
- Infection due to parasites
- Incubation 7 – 30 days
Risk factors:
- Children < 5 years old
- Pregnant women
- HIV/AIDS
- Non-immune migrants
- Travellers
Malaria transmission
Plasmodium parasite:
- P. falciparum – common & can cause severe disease
- P. vivax – common
- P. ovale
- P. malariae
- P. knowlesi
- Parasite lives in anopheles’ mosquito
- Spread to humans by bite of infected mosquito
- Bites at night from dusk to dawn
- No human-to-human transmission UNLESS
+ Through mother to foetus during pregnancy
+ Transfusion of infected blood
Malaria clinical presentation
Early symptoms:
- Head & body aches
- Fatigue & malaise
Later symptoms:
- Fever
- Sweating
- Rigors
- Chills
- Nausea
- Vomiting
- Diarrhoea
- Jaundice
Severe symptoms:
- Caused by P. falciparum
- Anaemia
- Seizures
- Mental confusion
- Renal failure
- Coma & death
Malaria prevention
- No vaccine available
- Insect avoidance
Chemoprophylaxis: - Not 100% effective - Takes into account patient factors: \+ Area being visited & duration of stay \+ Risk of exposure to malaria \+ Extent of drug resistance \+ Efficacy of the recommended drugs \+ Adverse effects \+ Patient-specific considerations
Malaria chemoprophylaxis
Medications:
- Malarone (atovaquone & proguanil) – 1 tab once daily & initiate 1-2 days prior to departure
- Doxycycline – 100 mg once daily & initiate 1-2 days prior to departure
- Mefloquine – 250 mg once weekly & initiate 2-3 weeks prior to departure
Duration:
- Continue prophylaxis up to 4 weeks after leaving endemic area
- EXCEPT Malarone – can be stopped 1 week after leaving
Malaria treatment
- Assess severity
- Identify source
- Identify drug resistance
- Allow for any patient related considerations
Treatment options:
+ Riamet (artemether & lumefantrine)
+ Malarone (atovaquone & proguanil)
Vector borne diseases: Dengue fever
Flavivirus:
- 4 serological types - DENV 1, 2, 3 & 4
Transmission - Aedes mosquito
- 2 species - A aegypti & A albopictus
- Bite during the day
- Prefer human dwellings
Dengue presentation
Symptoms:
- ~75% asymptomatic
- Sudden onset
- High fever
- Severe headaches
- Joint & muscle pain
- Eye pain
- Rash
- Minor haemorrhagic manifestations
- Serious complications uncommon
Duration:
- Incubation 4 – 10 days
- Illness typically occurs for 2 – 7 days
- Complete recovery can take 2 – 4 weeks
Dengue hemorrhagic fever
- Serious manifestation of dengue virus
- Can be associated with circulatory failure & shock
Characterised by 4 cardinal features
- Increased vascular permeability (plasma leakage syndrome)
- Marked thrombocytopenia
- Fever lasting 2 – 7 days
- Haemorrhagic symptoms
- Dengue shock syndrome (DSS) is cases where shock is also present
Dengue fever prevention
- Insect avoidance
- Vaccine not available to travellers at present
Dengvaxia:
- Live attenuated viral vaccine
- Schedule of 3 injections at 6 month intervals
- Available to individuals 9-45 years old living in endemic areas
Dengue fever management - treatment
Symptomatic:
- Best rest
- Fluids
- Paracetamol
Bleeding complications:
- Avoid aspirin & NSAIDs
- Blood transfusions
Vector borne diseases: Zika virus - flavivirus
Transmission:
- Bite of an infected Andes mosquito (A. aegypti & A. albopictus)
- Sexual contact – semen & vaginal fluids
- Transplacental, perinatal, breastfeeding
- Saliva
- Blood transfusion
- Haemodialysis
- Organ transplantation
Zika clinical presentation
Symptoms:
- ~80% asymptomatic
- Mild fever
- Headache
- Rash
- Joint & muscle pain
- Conjunctivitis
- Severe cases are rare
Duration:
- Incubation 2 – 14 days
- Symptoms resolve within 2 – 7 days
- Immunity develops after primary infection
Zika virus management
Prevention: - Insect bite avoidance - No vaccine or chemoprophylaxis currently available - Avoid zika in Pregnancy \+ Congenital Zika Syndrome \+ Precautions for both women & men
Treatment:
- Bed rest
- Paracetamol
- Fluids
Vector borne diseases: Yellow fever
- Viral haemorrhagic disease
Transmission:
- Bite of an infected mosquito – Aedes or Haemagogus spp.
3 transmission cycles:
- Jungle/Sylvatic – monkey-mosquito-monkey/human in the forest canopy
- Savannah/intermediate – monkey-mosquito-human or human-mosquito-human in jungle border areas
+ Most common type of outbreak in Africa
- Urban – human-mosquito-human with A. aegypti mosquitoes
Yellow fever presentation
Symptoms:
- Asymptomatic in many cases
Classical illness is classified by 3 stages:
- Period of infection (1st phase)
- Period of remission (2nd phase)
- Period of intoxication (3rd phase)
Duration:
- Incubation 3 – 6 days
- Acute phase illness 3 – 4 days
- Fatality rate of 50% within 7 – 10 days of toxic phase
Yellow fever management
Prevention: - Insect bite avoidance - Immunoprophylaxis Vaccination: \+ Live attenuated viral vaccine \+ Stamaril IM/SC \+ Single dose
Treatment:
- Supportive
- Bed rest
- Analgesia & antipyretic
- Fluids
- Prevent further transmission – mosquito avoidance
Food & water borne illnesses - Travellers diarrhoea
- 80 -90% of cases caused by bacteria
- Faecal – oral transmission
Prevention:
- Food precautions
- Water precautions
- Hygiene
Treatment:
- Oral rehydration
- Loperamide
- +/-Antibiotic
Food & water borne illnesses: Hepatitis A
Viral liver disease:
- Self limiting
- Range from mild to severe illness
Transmission:
- Contaminated food or water
- Human to human
- Faecal-oral route
Occurrence is in LIC (mostly)
Hepatitis A presentation
Symptoms:
- Fever
- Malaise
- Loss of appetite
- Diarrhoea
- Nausea
- Abdominal pain
- Dark coloured urine
- Jaundice
Duration:
- Incubation period 14 to 28 days
- Infection confers lifelong immunity
- Symptoms can last weeks to months
Hepatits A management
Prevention: - Food and water precautions - Hygiene - Immunoprophylaxis: Vaccination \+ Havrix \+ Inactivated vaccine \+ 2 doses, 6 – 12 months apart, IM
No treatment available
Food & water borne illnesses: Typhoid fever
- Notifiable disease NZ
- cute life-threatening illness
Bacterial
- Salmonella Typhi
- Salmonella paratyphi A, B or C
Transmission:
- Contaminated food or water
- Human to human
- Faecal-oral route
- Rarely through sexual contact
Typhoid presentation
Symptoms:
- Persistent high fevers
- Diarrhoea or constipation
- Malaise
- Abdominal pain
- Headache
- Loss of appetite
- Transient rash
Severe complications:
- Occur after 2 to 3 weeks
- Life threatening
- Intestinal haemorrhage
- Intestinal perforation
Duration:
- Incubation period 6 to 30 days
- Symptoms can last for 1 month if left untreated
Typhoid management
Prevention - Food & water precautions - Hygiene - Immunoprophylaxis: Vaccination \+ Efficacy 50-80% - Oral -> Vivotif 3 doses on alternate days \+ Injection -> Typherix IM single dose \+ Booster after 3 years if ongoing exposure
Treatment: - Fluids - Antibiotics \+ Drug resistance \+ Fluoroquinolones, azithromycin
Activity & injury: Hepatitis B
Acute viral infection of the liver
Transmission: - Blood - Bodily fluids \+ Saliva, menstrual, vagina & semen - Horizontal transmission - Mother to child during birth
Duration:
- Incubation period 30 – 180 days
- Acute phase -> several weeks
- Chronic infection -> complications
Hepatitis B presentation
Symptoms - Acute phase:
- Minimal symptoms
- Jaundice
- Dark urine
- Fatigue
- Abdominal pain
- Nausea & vomiting
Prevention: - Immunoprophylaxis: Vaccination \+ Energix – B IM \+ Usual schedule 0, 1, 6 months \+ Rapid schedule 0, 7, 21 days & booster at 12 months
Activity & injury: Rabies
Fatal viral disease
Transmission:
- Saliva from the bite of a rabid animal
- Aerosolised virus
- Organ transplantation
Symptoms:
- Fever
- Tingling, prickling or burning sensation at wound site
- Hydrophobia (fear of water)
- Paralysis
- Delirium
- Convulsions
Rabies management
Prevention: - Travellers should be aware of risks - Avoid handling wild animals - Immunoprophylaxis: Vaccination \+ Merieux IM on day 0, 7, 28
Post exposure: - Immediate wound cleansing - No pre exposure vaccination \+ Rabies immunoglobin (RIG) \+ Merieux IM 4-5 doses on day 0, 3, 7, 14 +/- 28 - Had pre exposure vaccination \+ Merieux IM 2 doses on day 0, 3 \+ Rabies immunoglobin not required
COVID-19
Caused by SARS-CoV-2 virus – 1st identified in Wuhan, China 2019
Transmission:
- Human – human direct/indirect contact
+ Direct: Saliva/secretion through mouth/nose/eyes
+ Indirect: Contaminated objects or surfaces (fomites)
- Other potential routes: fomite, faecal-oral, bloodborne, mother-to-child, & animal-to-human transmission
Incubation period:
- 5-6 days but can be up to 14 days
- Asymptomatic transmission
Symptoms:
- Fever, cough, fatigue, loss of smell, SOB
- Complication: Pneumonia, acute respiratory distress syndrome, cytokine storm
Prevention:
- Identify, test, isolate
- Face covering – fabric mask/surgical mask
- Contact/droplet precaution – PPE
- Hand hygiene / social distancing
COVID-19 impact
Global pandemic:
- Spanish flu
- Global recession
- Travel restrictions
Where can a pharmacist?
- Essential worker
- Bridge the gaps where GPs cannot
- Ensure continuity of care to patients
