301 Travel Health Flashcards

1
Q

What is travel health?

A

(Emporiatrics) a new medical specialty developed to meet health, safety and welfare needs of travellers

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2
Q

What is travel medicine?

A

Seeks to prevent illnesses and injuries occurring to travellers going abroad and manages problems arising travellers coming back

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3
Q

Common causes of mortality in travellers

A

Most: malaria
Drowning
In UK pop. overseas is ischaemic heart disease (35%) and trauma (25%)
Fatal accidents are MVAs

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4
Q

Contributory factors of MVAs abroad

A

Driving on opposite side of road (2.5x more likely to have MVA)
Tourists take greater risks overseas
Alcohol/drugs are often involved

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5
Q

Common causes of morbidity in travellers

A

Traveller’s diarrhoea (25-90% have symptoms in 1st 2 weeks), symptoms last 3-5 days and 25% alter travel plans, mostly due to E.Coli
Respiratory tract infections (13% report cold symptoms)
Malaria (incidence low but severe)

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6
Q

Most common vaccine-preventable conditions

A

Influenza and hepatitis A

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7
Q

Why has travel health become a thing?

A
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8
Q

Important trends in travellers are

A
  1. Number of travellers are increasing rapidly
  2. Changing trends in destination choice
  3. Changes in traveller type
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9
Q

What are VFRs?

A

Visiting friends and family

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10
Q

Why are VFRs important?

A

Spend close proximity with local population
Often complacent
Have poor perception of health risks at destination
Do not always accept travel health recommendations
Often wrongly assume immunity to tropical conditions
Only accept vaccinations are legally required

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11
Q

Briefly describe the UNWTO trends and discuss implications of trends on significance of travel health issues, compared to other public health concerns

A
  1. Health and safety protocols: increased hygiene & COVID-19 protocols integrate travel health with public health goals
  2. Wellness tourism: rising demand for health-focused trips connects travel health to mental and physical wellbeing
  3. Digital health: use of apps for health monitoring & vaccine verification
  4. Environmental health: climate impact awareness highlights disease risks, aligning travel health with global health
  5. Resilient policies: adaptable travel health policies enhance public health emergency preparedness
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12
Q

What do travel health services do?

A

36-52% international travellers obtain travel health advice before journey
Information sources accessed (GPs 57-75%, travel clinics 35-35%, pharmacists 0-24%)

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13
Q

Do pharmacists have a role in travel health?

A

Collect meds. and vaccines or OTC and 1st aid remedies
To check with pharmacist whether to visit GP/travel clinic
Take advantage of opening hours, location, free advice and/or purchase other travel supplies

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14
Q

Examples of novel pharmacy-run models

A
  1. Clinical Pharmacy International Travel Clinic (CPITC) operated by KP in Denver, USA
  2. Grampian Community Pharmacy Service, UK
  3. USC Clinic, USA
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15
Q

Human gut:
Mucosal length
How many diverse symbionts?
How many bacterial species?

A

200-300m^2 of mucosa
Ten trillion
100-1000

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16
Q

What is a microbiome?
How much larger than human genome?

A

Collective genes of microbiota
150x

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17
Q

When is an individual’s microbiome established?

A

2 years of age but subtle changes occur in certain life circumstances

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18
Q

Species of GI biofilm

A

Pepto streptococcus
E.coli
Klebsiella Spp.
Clostridium
Lactobacillus
Proteus Spp.
Bacteroidetes
Bifidobacterium
Enterococcus Spp.

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19
Q

Development of human GI microbiota after birth

A

GI tract is rapidly colonised, with life events such as illness, antibiotic treatment & changes in diet causing chaotic shifts in microbiota

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20
Q

What affects human GI microbiota composition?
Mother and foetus composition: vaginal vs C-section delivery

A

Mode of delivery
Whilst faecal microbiota of 72% of vaginally delivered infants resembles that of their mothers’ faecal microbiota, in babies delivered by C-section, this percentage is reduced to only 41%

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21
Q

By 2.5 years of age, what do infant microbiota resemble?

A

The composition, diversity and functional capabilities resemble those of adult microbiota

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22
Q

What do gut microbiota provide?

A

Range of beneficial properties to host
Produce enzymes that aid in dietary compound breakdown (lactose, vitamins) or compounds from liver (bilirubin) & allow re-absorption
Lactic acid bacteria are key organisms in production of vitamin B12
Produce bacteriocins that kill other bacteria
Bacterial competition to inhibit growth of pathogenic bacteria (inhibit attachment)

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23
Q

What are bacteriocins?

A

Anti-microbial peptides

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24
Q

What organisms cannot synthesise B12?

A

Animals
Plants
Fungi

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25
Bacterial competition: Interference competition Exploitative competition
1. Invokes antagonistic factor produced to impede competitors (bacteriocins) 2. Passive in sense that one organism depletes its surrounding of nutrients, thereby preventing competitors from gaining access to those resources
26
What effects can microflora destruction have on an individual's health?
1. Caused by antibiotics, infection, chemotherapy 2. Can lead to higher risk of infection by pathogenic bacteria 3. Increased risk of allergy 4. Carriage of certain strains can lead to IBD
27
Effect of antibiotics on microflora and pathogens: Before antibiotic treatment After antibiotic treatment
1. Microflora dominate, creating a barrier over epithelial cells and limiting pathogen presence 2. Microflora are significantly reduced, making room for pathogens to invade, potentially harming the epithelial cells
28
Bacterial relationships: Antagonistic Biofilms Symbiotic Synergistic
1. Harms other organism 2. Complex relationships among numerous microorganisms, often different species 3. Organisms are interdependent & rarely live outside relationship 4. Organisms cooperate to gain equal advantages
29
GI diseases
Crohn's Coeliac Antibiotic associated diarrhoea (C.difficile) Food poisoning Food allergy reactions IBS
30
Causation of IBD
Stress & physical inactivity Environmental factors Medications (antibiotics) Diet Smoking Hygiene Genetic susceptibility Gut microbiome Appendectomy Sleep
31
How does antibiotic associated diarrhoea mean an infection may occur?
By ingestion of spores released by another infected person Spores can survive on surfaces for long time
32
Antibiotics, dysbiosis and restoration of gut health: Antibiotic exposure Infection Treatment Options (antibiotics and faecal microbiota transplantation (FMT))
1. Leads to dysbiosis (imbalance of gut microbes) and increased susceptibility to infections like C. difficile 2. Causes toxin-mediated disruption of the gut lining 3. Used to treat C. difficile infection but may worsen dysbiosis 4.Restores microbial diversity & promotes long-term gut health (homeostasis)
33
What can glucosyltransferases cause damage to antibiotic associated diarrhoea?
Damage cytoskeleton of target cells
34
Symptoms of IBS
Constipation/diarrhoea, bloating, flatulence, stomach cramps
35
What is IBS caused by?
Over sensitisation of whole gut
36
What are probiotics?
Live non-pathogenic microorganisms administered to improve microbial balance Bacteria found in GI tract that aid digestion
37
What are probiotics available as?
Capsules, tablet Packets or powders Common in yoghurt or diary drinks
38
Examples of good bacteria
Lactococcus Lactobacillus Lactobacillus bifidus
39
Examples of bad bacteria
Clostridium perfringens Staphylococcus Escherichia coli
40
Mechanisms of gut microbiota in supporting intestinal health: epithelial barrier enhancement
1. Produces mucus and antimicrobial substances 2. Promotes adhesion complex formation, increasing mucosal binding
41
Mechanisms of gut microbiota in supporting intestinal health: colonisation resistance
1. Competes against pathogens for nutrients & adhesion sites 2. Immunomodulatory effects
42
Mechanisms of gut microbiota in supporting intestinal health: organic acids and bacteriocins
1. Produce acetic & lactic acids 2. Have antimicrobial properties
43
Mechanisms of gut microbiota in supporting intestinal health: immune system modulation
Involves dendritic cells, epithelial cells and T lymphocytes (T killer cells and B cells)
44
Mechanisms of gut microbiota in supporting intestinal health: mucosal binding proteins
Support adhesion and stability through sortase-dependent proteins
45
How can bacterial species express certain genes?
Genetically manipulated
46
Carriage of bacteriocins in probiotic strains
Carry enzymes to break down lactose for lactose intolerant people (in research)
47
Probiotics and antibiotic associated diarrhoea
Thought to prevent AAD onset or C.difficile while taking antibiotics Strain specific - need to express proteases that break down toxins No use for treatment yet
48
Other potential uses for probiotics
1. May protect against infection with H.Pylori 2. Reduce symptoms of IBS sufferers 3. Prevent food allergies/intolerances 4. Prevent against other infections - candidiasis
49
Disadvantages of probiotics
1. Cause septicaemia & bacteraemia if patient has bowel lesions 2. Cause septicaemia & bacteraemia in critically ill patients 3. May cause fungemia (Saccharomyces) 4. Can increase sensitivity to allergens 5. May add to obesity trends - high fat/sugar content in yoghurts 6. Bacteria may be killed with stomach acid - how much actually survives
50
Key elements of a quality travel health service
1. Formal/thorough pre-travel health risk assessment 2. Individualised, risk management strategy 3. Process of risk communication 4. Formal/thorough assessment system for returning travellers Care and advice given to traveller as documented
51
What should be involved in pre and post-travel health services?
Utilisation of risk management approach is considered integral and essential component
52
Aims of a quality travel health service
1. Prevent and/or minimise risks with travel for individuals 2. Manage problems that occur during & as result of journey
53
Aims of pre-travel risk assessment
1. Prepare traveller for journey 2. Minimise and manage health risks with education, vaccines and/or meds May require multiple visits, perform 4-8 weeks before travel A systematic approach recommended using standardised questionnaires, interview schedules and/or data collection tools
54
NaTHNaC/CDC/WHO suggests pre-travel risk assessment consisting of...
1. Assessment of traveller's baseline health 2. Review of risks associated with destination 3. Decide which vaccines (and medical interventions) are required 4. Educate traveller about disease prevention & health maintenance
55
Key points to consider with traveller: itinerary-related data
Countries & regions being visited (+ stop overs) Region (capital, rural) Date & length of stay in each area Purpose of travel (tourism, business, VFR) Modes of transport Planned activities (high risk) Type/standard of accommodation Potential disease exposure at each destination
56
Key points to consider with traveller: traveller-related data
Age and gender Vaccination Hx Full medical, allergy & medication Hx Pregnant/breastfeeding? Planned medical care or surgery close to travel Attitudes/traits of traveller i.e. likelihood of accepting advice Budget
57
Travel vaccinations: required vaccines
Legally required for certain destinations Yellow fever - all travellers returning from endemic areas for yellow fever would be quarantined on arrival if they had not been vaccinated prior to departure
58
Travel vaccinations: routine vaccines
Standard 'childhood' vaccines (e.g. Australian NIPS) Problem - increasingly children not vaccinated and/or adults have not had recent boosters
59
Travel vaccinations: recommended vaccines
i.e. those vaccines recommended by bodies such as CDC and NaTHNaC for particular destination - Cholera, typhoid, Japanese encephalitis, Rabies
60
What needs to be planned before travel in adequate time?
Appropriate vaccination program
61
Educational interventions: obligatory counselling
Insect precautions, malaria chemoprophylaxis, food & water, traveller's diarrhoea, current disease outbreaks, water-borne disease, vector-borne, climate, jet lag, trauma, sexual activity, 1st aid kits, health insurance, crime & safety
62
Educational interventions: optional counselling
Evironmental risks: altitude, diving, adventure, motion sickness, heat & cold, pregnant women, elderly, immunocompromised, parasites, pathogens, zoonoses
63
Traveller's Diarrhoea
3 loose watery stools in 24 hour period with/without abdominal pain, nausea, vomiting, fever, cramps, blood or mucus in stools, faecal urgency 50% of stool samples are negative for pathological organisms But 95% of cases respond to antibiotics, therefore now thought most are infective in origin
64
Enterotoxigenic E.coli (ETEC) causes, usual incubation period and average duration of illness
10-45% of TD 12 hrs to 3 days 5 days
65
Noroviruses causes, usual incubation period and average duration of illness
0-10% 18-48 hrs 24-48 hrs
66
Parasites: giardia intestinalis causes, usual incubation period and average duration of illness
0-5% 12-15 days Weeks to months
67
Risk factors for Traveller's Diarrhoea
Adventurous behaviour Particular destinations Season Length of stay Lack of travel experience Consumption of unclean water or food Medication with H2 receptor blockers or PPIs
68
General principles of food hygiene
Initially, may be best for traveller to stick with usual diet Prepare food personally rather than eating in hotels and restaurants Avoid raw foods or food that has to be reheated
69
Food hygiene preventative measures
Dry foods are generally safer than moist Raw fruit an veg must be washed thoroughly and soaked, avoid fruit and veg that cannot be peeled Consider risk of infection from contaminated cutlery or crockery Maintain good personal hygiene such as regular handwashing (use alcohol hand rub) Local foods may be safer in restaurant than westernised foods
70
Water treatment
1. Boiling for 3-5 mins 2. Use of chlorine or iodine 3. Filtration 4. Vaccination 5. Chemoprophylaxis
71
Goals of Traveller's Diarrhoea treatment
Avoid dehydration Reduce severity and duration of symptoms Prevent interruption of planned activities
72
Traveller's Diarrhoea treatment: hydration and diet
Use of ORS well established in children and elderly but less evidence in healthy adults
73
Traveller's Diarrhoea treatment: symptomatic treatment - loperamide and antibiotics
1. Antimotility agent of choice, not to be given in young children or those with diarrhoea & fever or if there is gross blood in stools 2. Improve condition within 20-36 hrs & shorten course of disease by 1-2 days Fluoroquinolones effective unless resistant Campylobacter present Current guidelines = stat dose of azithromycin or norfloxacin If no improvement or fever or blood present then use 2-3 days course
74
Traveller's Diarrhoea: combination therapy
UK/AUS do not carry Abx so follow diarrhoea management guidance Mild: rehydration Moderate: add loperamide Severe: seek medical advice
75
Traveller's Diarrhoea: travelling to a remote location
Carry ciprofloxacin & metronidazole - if severe symptoms, start ciprofloxacin for 3-5 days plus metronidazole (if persistent >14 days)
76
Diarrhoea in returning traveller
13% of travellers return home ill have diarrhoea If fever or gross blood present in stools is NOT present: symptomatic treatment Serology may help for amoebiasis, schistosomiasis or strongyloidiasis No clear diagnosis treat for giardia Check for non-invasive causes (IBD)
77
Factors implicated in malaria prevalence
Global warming Drug resistance of Plasmodium parasite Insecticide resistance of vector and population movements
78
5 Plasmodium species that affect humans
1. Plasmodium falciparum 2. P.vivax (more temperatre climate) 3. P.ovale (sub-Saharan Africa, SE Asia) 4. P.malariae (endemic areas) 5. (P.knowlesii) P.falciparum (severe fatal form, resistant to chloroquine - sub-Saharan Africa & south America & Asia)
79
Clinical features of malaria
Early symptoms in 3 phases: coldness with rigors, feeling hot & flushed & intense sweating as attack resolves With falciparum malaria, the fevers are irregular with coma and death occurring within as little as 24 hours after the development of initial symptoms In falciparum malaria, the surface of the RBCs is altered & adhere to the walls of blood vessels which can lead to cerebral malaria
80
Benign clinical feature of malaria
With the benign forms of malaria, fevers are experienced in a synchronised way as the schizonts rupture within the same time period each time, – every 48 hours for P.vivax and every 72 hours for P.malariae (Cannot be used to distinguish between forms)
81
Other complications of malaria
Thrombocytopenia, renal insufficiency , hypoglycaemia and splenomegaly
82
Other symptoms of malaria
Myalgia and arthralgia, diarrhoea, headache, nausea, vomiting and malaise
83
Malaria chemoprophylaxis regimen is based on?
The destination Country & area to be visited Time of year Rural or urban Activities at destination Accommodation & style of travel Presence of contraindications Age, pregnancy, previous experience with antimalarials, medical history (neuropsychiatric illness, seizures etc)
84
When should malaria chemoprophylaxis be started?
Start chemoprophylaxis 1 week before entering endemic area and continue for 4 weeks post return Ideally, Mefloquine should be started 2-3 weeks before leaving (to check tolerance) Atovoaquone/Proguanil (Malarone) may be started 1-2 days before & 7 days after leaving an endemic area Doxycycline may be started 2 days before entering an endemic area (if insufficient time)
85
Malaria standby treatment (SBT)
Prescribed to take with them, if malaria expected & over 24 hours from medical care, they start treatment
86
Why are H2 receptor blockers and PPIs a risk factor for Traveller's Diarrhoea?
Reduce gastric acid secretion which kill bacteria
87
Why should we avoid buying antimalarials overseas?
Many counterfeit preparations are distributed in developing countries
88
Malaria standby treatment (SBT) - counselling points
They must still seek medical advice as soon as possible Routine prophylaxis should be continued during & after the attack Mefloquine or atovaquone/proguanil cannot be used as SBT if it was being used as the prophylactic agent Co-artemether (Artemether 20mg & lumefantrine 120mg (Riamet)) is a useful agent for SBT Dose for adult (>12 years/>35kg) = 4 tablets at time 0, 8, 24, 36, 48 & 60 hours Patient must be trained to recognise symptoms (can be trained to use a test kit)
89
Malaria - returning traveller
Consider malaria as a possibility in anyone presenting with a febrile illness who has visited an endemic area in the last 12 months
90
Malaria - bite avoidance
Chemoprophylaxis is not 100% effective (75-95% effective) Apply insect repellents to the skin (Use at least 20% (50% recommended by UK services) DEET (Diethyltoluamide), avoid large amounts of DEET on young children (risk of toxic encephalopathy)) Apply insecticides (Permethrin) to clothing Use knockdown sprays, insecticide-impregnated mats or mosquito coils to clear rooms of mosquitoes Avoid night time exposure for Anopheles mosquitoes & daytime exposure for Aedes mosquitoes Cover up arms & legs, wear light colours & thicker materials Sleep under insecticide-impregnated mosquito nets Sleep away from stagnant water that could harbour mosquitoes Be extra cautious during the wet season Do not use perfumes or aftershave lotion
91
Malaria in pregnancy
Malaria is more likely to be severe in pregnancy: Acidosis, hypoglycaemia & pulmonary oedema are more common Also risk to the foetus: low birth weight & foetal death
92
Pregnant women and endemic areas
Ideally should not travel to areas Chloroquine & proguanil have been used in pregnancy Doxycycline avoided after the first 18 weeks Mefloquine should be avoided throughout pregnancy if possible Artesunate, quinine, clindamycin & proguanil may be used to treat malaria
93
Common/important vaccines to consider
Typhoid Cholera Polio Hep A Hep B Meningitis Rabies
94
Rabies: causes and transmission
Caused by rhabdovirus of genus Lyssavirus Zoonotic disease affecting range of animals Virus present in saliva of infected animal and transferred to humans via bites & scratches Unless treated, rabies is invariably a fatal disease causing severe acute viral encephalomyelitis
95
Rabies: risk to travellers
Prevalent in rural areas of Africa, Asia, Europe, North & South America, 90% deaths reported in Asia AUS, UK, NZ rabies-free Conundrum - rabies vaccine expensive & for most travellers risk quite low
96
Travellers at high risk
1. Travelling on bicycles as they are more likely to be chased and bitten by local dogs 2. Small children likely to be attracted to animals 3. People working with animals 4. Adventure travellers who explore caves with often frequented by bats
97
Rabies: Clinical features
Initial symptoms: apprehension, headache, fever & sensory changes Excitability, hallucinations & aerophobia common Few days, progress to hydrophobia, delirium, convulsions & death
98
Rabies: travellers needs to consider
1. Cost of pre-exposure vaccine vs risk 2. Rabies exposure - what is the availability of rabies Ig & vaccine for post-exposure treatment & ability to treat rabies in local hospitals
99
DVT/VTE: "Economy Class Syndrome"
Claimed travellers who take long-haul flights at risk of DVTs lead to PE (life-threatening) Lack mobility for long periods combined with cramped conditions in cabin cause major causative factors
100
DVT/VTE: Contributory factors for air travellers
1. Lower partial pressure of oxygen in cabin at altitude during flight and effect on coagulation 2. Consumption of alcohol & caffeine may contribute towards dehydration & sluggish circulation
101
Risk factors for DVT in travellers
Previous Hx, flights >12 hrs, elderly, overweight, smoking, reduced motility, dehydration, pregnancy, hypercoagulability
102
Jet lag
Psychological & physiological symptoms of desynchronisation crossing time zones Shift 3-4 hrs in time zone upsets body's circadian rhythm
103
Jet lag symptoms
Difficulty sleeping, fatigue, confusion, irritability, digestive disorders, joint stiffness & headache
104
Jet lag factors that aggravate
1. Direction if travel (worse eastwards) 2. Age (elderly) 3. No. time zones crossed - (greater no.) 4. Napping (slows adjustment) 5. Previous bad travel experiences 6. Sleep deprivation (prior to journey) 7. Dehydration 8. Stress 9. Poor diet
105
Melatonin in jet lag
Reduce effects of jet lag (studies show benefits but not consistent) Melatonin should be avoided in epileptics & those taking warfarin
106
Measures taken before, during and after flight for jet lag
1. Well rested, choose flight times, rest after flight & no activities 2. Avoid sleep deprivation, set watches of time back home, drink fluids, avoid alcohol & caffeine, use temazepam for sleep deprivation 3. Eat & sleep pattern of local time, sleeping tablets for 1st few nights
107
Cruise ship risks
Diverse locations in crowded, semi-enclosed environment Outbreaks sustained for multiple voyages Port visits expose vector-borne disease Remote location = need to use ship medical facilities
108
Illness on-board cruise ship include
Respiratory illness (19-29%) Seasickness (1-25%) Slips/falls (12-18%) GI illness (9-10%) Deaths (usually CV events) - 0.6-9.8 deaths per million passenger nights
109
Specific illness on cruise ships: GI illness
>90% GI outbreaks with confirmed cause Reasons: - Low infection dose - Easy person-person transmission - Prolonged viral shedding - No long-term immunity - Virus's ability to survive routine cleaning procedures Advise on hand hygiene & follow isolation & infection control measures
110
Specific illnesses on cruise ships: respiratory illness
Influenza Legionnaires' disease (20% cases reported Legionnaires' disease causes in US are travel related) Covid-19 (Ruby Princess Outbreak)
111
Travelling with medicines
Keep away from children Carry written instructions & letter of authorisation Keep in packaging Legal issues Quantities (adequate supply)
112
Potential risks in purchasing medicines overseas
1. Attempt to save space in luggage 2. Save money (assume cheaper overseas) 3. Lost/forgotten regular meds 4. Treat unexpected travel-related condition 5. Usurp pricing arrangement of pharmaceuticals in own country (Communication issues, identification, availability, quality)
113
Medical kits for travellers: factors
Itinerary Size of group Size of kit & amount of available space Chronic diseases & regular meds Packaging Stability of meds Legal & ethical issues
114
Life cycle of malaria parasites: Transmission Hepatic stage Blood stage Gametocyte formation Prophylaxis
1. Anopheles mosquito bite injects sporozoites into the bloodstream 2. Sporozoites enter liver cells, forming schizonts; they multiply & release merozoites Some (in Plasmodium vivax and P. ovale) become dormant hypnozoites, causing relapses 3. Merozoites infect RBCs, forming schizonts, which rupture, releasing more merozoites & continuing the cycle, some develop into gametocytes 4. Taken up by another mosquito, continuing the cycle in the mosquito's gut 5. Chloroquine target blood stage, while others like primaquine prevent relapse by targeting liver stages
115
Key chemoprophylactic agents in malaria: chloroquine Usual regimen MOA Major S/Es Current Use Cautions
1. 300mg base per week 2. Suppresses blood parasites 3. Fatal cardiac arrhythmia in overdose, N + V, chronic retinopathy, itching, tinnitus, dizziness 4. Malaria suppression & treatment, resistance widepsread with P.falciparum but useful with P.vivax (no longer available in AUS) 5. Do not use in epileptic, caution in warfarin, appears safe in pregnancy & breastfeeding
116
Key chemoprophylactic agents in malaria: doxycycline Usual regimen MOA Major S/Es Current Use Cautions
1. 100mg daily 2. Suppresses blood parasites & has variable effects against liver stages of P.falciparum 3. GI upset, sun sensitisation, thrush 4. Prophylaxis in areas with chloroquine and/or mefloquine resistance 5. Do not use in pregnancy, children U8, women with recurrent vaginal thrush, caution in contraceptives & patients known or believed to have oesophagitis
117
Key chemoprophylactic agents in malaria: mefloquine Usual regimen MOA Major S/Es Current Use Cautions
1. 250mg once weekly 2. Suppresses blood parasites 3. Dizziness, dysphoria, psychosis, seizures 4. Prophylaxis for most travellers to malarial areas, except some SE Asia where resistance present 5. Use extreme care with beta blockers & CCBs, avoid use with similar antimalarials, do not use in neurological or psychiatric disease or certain occupational groups
118
Key chemoprophylactic agents in malaria: Malarone - atovaquone (250mg) & proguanil (100mg) Usual regimen MOA Major S/Es Current Use Cautions
1. One tablet daily 2. Acts against blood schizonts & liver stages, synergistic effect 3. Generally mild & limited duration, rash, abdominal pain, N + V, diarrhoea, anorexia, headache, dizziness, myalgia, insomnia 4. Prophylaxis of malaria, treatment of uncomplicated falciparum malaria 5. Watch for resistance
119
Key chemoprophylactic agents in malaria: proguanil Usual regimen MOA Major S/Es Current Use Cautions
1. 200mg daily for prophylaxis 2. Kills blood and liver parasites 3. Mouth ulcers 4. Prophylaxis of malaria usually with chloroquine 5. Combo with chloroquine used with extreme caution in renal failure patients, appears safe in pregnancy, do not use combo in people with heart block