TRAVEL IMMUNISATION UPDATE 2017 V 2.0. Dr Nick Kimpton MBBS FRACGP CTH MPHTM Ballarat Medical Centre 10 Drummond St South Ballarat 3350 Ph

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2 TRAVEL IMMUNISATION UPDATE 2017 V 2.0 Dr Nick Kimpton MBBS FRACGP CTH MPHTM Ballarat Medical Centre 10 Drummond St South Ballarat 3350 Ph

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8 ROUTINE VACCINATIONS [NOT SPECIFIC TO TRAVEL] DTP MMR Polio Hep B HiB Influenza Pneumococcal Varicella Meningococcal C /ACWY HPV

9 ITINERARIES WITH COMPULSORY/REQUIRED VACCINATIONS International Certificate of Vaccination or Prophylaxis [ICVP] currently only Yellow Fever but may be altered under International Health Regulations at any time The Haj and Umra, currently for Australian citizens only Men ACWY is compulsory, influenza vaccine strongly recommended Employment /schooling requirements Outside of these itineraries, immunisations, antimalarials and other health precautions are the decision of the traveller with our input and guidance The concept of the VFR as a high risk traveller [Visiting Friends and Relatives] Children, immunocompromised, pregnant women etc all have unique considerations

10 TRAVEL SPECIFIC RECOMMENDED VACCINES Hepatitis A Typhoid Cholera Meningococcal ACWY Yellow Fever Japanese Encephalitis Rabies Tuberculosis Tick Borne Encephalitis

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12 INFLUENZA The commonest vaccine preventable disease of travel Only Southern Hemisphere formulation currently available in Australia Despite this year s poor protection I would offer this for all tropical travel and for appropriate seasonal risk in temperate zones

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14 MEASLES Frequently forgotten in the context of a travel consultation Approximately 260,000 cases [2014] and 146,000 deaths [2013] worldwide One of the most infectious agents known to humans Complications 1/3 infections, Deaths 1/500 in Western population More than 50% of infections in Australians are contracted overseas during travel Remember d.o.b or later and especially Older than that 95% immune BUT yo only 60-80% ie around 1/3 do not have protective levels of antibodies? Immunisation does not induce as good a long term memory as infection Look for evidence of 2 doses of vaccine or serology to be protected No evidence give 2 doses [ I would even discuss a booster dose around 50] Remember is a live vaccine so must give with other live vaccines or separated by a minimum of 4 weeks

15 MUMPS Ditto for measles but less lethal and less infectious Remember d.o.b or later and especially Look for evidence of 2 doses of vaccine or serology to be protected Recently an outbreak in Auckland NZ [mainly in Maori and Pacific Islander communities] Mumps is a highly infectious disease. Parotitis is a painful and common symptom. Orchitis, meningitis, and encephalitis are less common complications, but potentially serious. Recommendations for inclusion of a third dose of mumps vaccine in routine vaccination schedules are under consideration in several countries, including the U.S. Meanwhile, travel health advisors may wish to offer a third dose of mumps vaccine to young adult and adult travellers at specific high-risk of mumps as two-dose immunity clearly wanes.

16 MENINGOCOCCAL VACCINES Men C given routinely in Australia at 12 months, Men B now available and recommended for 1-5 yo and yo Men ACWY [conjugate] currently available free in Vic for 15-19yo Men A has been especially important in sub-saharan Africa [meningitis belt] but is waning with C and W becoming the predominant strains MenB is uncommon in Africa but important for Europe, North America, Australia and New Zealand Quadrivalent vaccines for travel to protect against ACWY strains Conjugate vaccines, newer longer lasting and prevent nasal carriage [? boost after 5 years in adults if increased risk or immunosupressed ] Polysaccharide vaccines cheaper, should no longer be available [only use if not anticipating further travel to risk area,booster appears less effective than initial dose]

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18 MENINGOCOCCAL VACCINATION FOR TRAVELLERS Men cacwy required within last 5 years for travellers to Haj and Umra Consider for all people especially yo who travel and live in close contact eg Residential colleges, youth hostels or doing military service Consider for younger children especially VFRs or anyone who is immunocompromised For travellers to regions in the meningitis belt depending on the time and duration of travel [there are biannual peaks of incidence that vary across the region] look at each country for specific recommendations

19 YELLOW FEVER Currently the only mandated vaccine needing an ICVP A flavivirus with a large wild animal [non human primates] reservoir through tropical Central and South America, and sub-saharan Africa endemic infection with intermittent epidemics Causes intermittent epidemics when aedes mosquitoes in urban settings cause human to human transmission, but also occasional cases where people come into contact with infected mosquitoes in jungles and savannah Highest risk at the end of the wet season July October for Africa and January May for South America

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22 YELLOW FEVER 2017 epidemic of yellow fever in Brazil that has spread beyond the usual boundaries on the map above to reach the Atlantic coast and affect urban areas of Rio de Janeiro, Sao Paulo and Salvador and the surrounding states Historically there have been outbreaks of Yellow Fever in the th century in Europe and North America following infected people moving into those countries and establishing local transmission

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25 YELLOW FEVER Currently people entering Australia require a valid ICVP for Yellow Fever if coming from a country listed as having endemic YF [ 47 in Africa and 13 in S America] within the last 6 days, in accordance with the International Health Regulations

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27 YELLOW FEVER From June 2016, international yellow fever vaccination certificates presented at Australia s border will be accepted even if the vaccination was given more than ten years ago. Individuals who cannot provide a yellow fever vaccination certificate at the border will still be required to go through border control processes when entering Australia. As is current practice, entry to Australia will not be refused on the basis of non-compliance with yellow fever monitoring and control requirements. f/content/health-pubhlth-strateg-communicfactsheets-yellow.htm

28 YELLOW FEVER VACCINATION A live attenuated vaccine that provides lifelong protection beginning 10 days after vaccination Exclude from vaccination Severe allergy to egg protein Immune compromise [steroids and other immune suppressants eg methotrexate,many monoclonal antibodies, HIV with CD4 counts below certain levels Previous thymus surgery or radiation Pregnant women [unless risk of disease outweighs risks to patient and fetus] Children < 9 months of age [consider for 6-9 months old if risk of disease outweighs risks to patient of vaccine]

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30 YELLOW FEVER VACCINATION Certificates issued from June 2016 should read valid for the life of the person vaccinated A letter of exemption can by provided by a YF approved medical practitioner where risks of vaccination are too great Sometimes this is easy, often a more complex decision and requires consideration of risks to the traveller and the community of importation of YF and the risks of doing harm through vaccination I will normally do an exemption letter specific to a particular time and itinerary to prevent its ongoing or indefinite use if the exemption is not for an absolute contraindication

31 JAPANESE ENCEPHALITIS [LOW RISK HIGH IMPACT] Another mosquito borne flavivirus closely related to Murray Valley Encephalitis, the commonest cause of encephalitis in SE Asia Carried by migratory water birds eg herons and egrets Commonest where there is flood irrigation and pig farming [ humans and most other domestic animals are dead end hosts] Absolute risk per traveller is very low [ 1/250,000-1,000,000 per 2 week trip?] Risk increased by duration of travel, time in rural locations and season Worldwide estimated to be 68,000 cases/yr and 13-21,000 deaths mostly in children, with epidemics occurring every 2-15 years

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33 JAPANESE ENCEPHALITIS Risk of significant illness estimated at only 1/250 infections [vast majority are asymptomatic or non specific viral illness] But with severe disease 1/3 die, 1/3 have permanent neurologic sequelae cases in Australians, all acquired overseas. But a death in a 60 yo Australian who spent 10 days North of Phuket in June 2017 In subtropical regions monsoonal illness, in tropical regions all year round Because of vaccination local infection rates in humans do not reflect risk to travellers

34 JE VACCINATION Two vaccines available in Aus Imojev, live chimeric vaccine of JE spliced into YF single dose, boost after 1-2 years if given between 9 mo and 18yrs, no booster needed for adults Jespect [Ixiaro], inactivated JE virus 2 doses 4 weeks apart no booster needed if given 9 mo to 18yrs but boost after 1-2 yrs in adults

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36 MOSQUITO BITE AVOIDANCE No bites, no malaria, Dengue, Zika,Chikungunyah, JE etc. Nets/ AC/ Screened rooms Repellent[DEET/Picardin] Cover up /Permethrin Insecticide /Knockdown/Coils

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38 RABIES [LYSSAVIRUS] Includes all the classic rabies strains and several others including Australian Bat Lyssavirus Estimated to cause 80,000 deaths/year predominantly in Asia and Africa Wound from terrestrial mammal, a bite a scratch or a lick on broken skin [or mucous membrane] Tell patients any animal with fur All wounds regardless of vaccination status are managed the same initially ie wash vigorously and seek urgent medical attention

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40 RABIES Pre Exposure Prophylaxis [PreP] Post Exposure Prophylaxis [PEP] 2 Vaccines, Merieux Inactivated Rabies Vaccine [cell culture derived] and Rabipur Inactivated Rabies Vaccine [ chick embryo derived] very similar but cant use Rabipur if egg protein allergy Imogam Rabies Immunoglobulin [HRIG] human derived is the only Immunoglobulin used in Aus [many other countries especially in Asia use a horse derived immunoglobulin] PreP is 3 doses IM on days 0,7, 21-28, for dog bite rabies in normal population considered to be lifelong cover PEP if previously vaccinated is 2 doses on days 0 and 3 PEP if not vaccinated is HRIG into the wound [calculated on body weight] and 4 doses of vaccine days 0,3,7,14 but if immunocompromised add a fifth dose on day 28

41 RABIES, SOME PRINCIPLES Awareness is at least as important as vaccination The principle of PrEP is to create boostable immunity Tell patients that any bite or scratch or a lick on broken skin from a furry animal is a risk Do not give incomplete vaccine series as HRIG cannot be used if a person has ever been vaccinated [ any dose more than 7 days previously] and it is not protective Travel clinics can offer ID rabies vaccination [off label]as it is less expensive.it is not recommended by the Australian Immunisation Guidelines [requires significant experience to administer] but is widely used in Australian Travel Clinics and overseas If you see returned travellers who have had a potential rabies exposure either untreated [at any time in the past] or who have started PEP overseas contact the health dept to get access to HRIG and further doses of vaccine[or immediately refer to a clinic that is experienced in handling rabies PEP]

42 RABIES PEP In Victoria if you are contacted by someone after a potential rabies exposure you need to know; Animal contact date and bite site/type of contact Commencement date of vaccination and regime given Patient s weight Any immunocompromise in the bitten person Then ring the health dept

43 QUESTIONS? Good Reference Sites WHO The Australian Immunisation Handbook Content/Handbook10-home CDC Smartraveller [Aus Govt]

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45 HEPATITIS A What a great vaccine! Single dose of age appropriate vaccine good for 1-3 years 2 doses 6 or more months apart for lifelong cover Can be given from 1 year of age Serology if unsure of vaccination history, adult with history of hepatitis, immigrant, or over 65 and may have had wild disease Worthwhile for anyone travelling outside of low risk Developed Countries No contraindication to administering with any other vaccines Available in combination with typhoid and Hepatitis B

46 TYPHOID Injectable Polysaccharide vaccine for 2yo and above, contraindications only allergy to vaccine or components Oral live attenuated [days 1,3,5 ] for 6yo and above, precautions, must swallow whole and cannot be given with antibiotics, separate by at least 8 hours from cholera vaccine Both provide 3 years of protection then revaccinate if ongoing risk [ 4 dose oral is good for 5 years], may get some partial protection against paratyphoid from oral vaccine too Important disease in Indian subcontinent but anywhere outside of first world countries

47 CHOLERA Oral killed vaccine of 4 of the 01 strains and recombinant B subunit Children 2-6yo, 3 doses 1-6 weeks apart, over 6yo 2 doses 1-6 weeks apart Contraindications only allergy to vaccine or components Not advised for pregnant or breastfeeding Don t give during acute GI illness or within 8 hours of oral typhoid Good short term efficacy but rapidly wanes [no protection against 0139] Probable cross protection against ETEC [enterotoxigenic e coli] for 3 months giving approximately a 10% reduction in bacterial gastroenteritis, although there is significant dispute regarding this Main indication is high risk high exposure eg aid workers in refugee or disaster relief Consider for ETEC cross protection if person is at much greater risk of gastroenteritis or serious outcomes Booster doses if ongoing exposure at 6 months for 2-6yo and 1-2 years for over 6yo. If outside of these periods a new primary course is advised

48 TUBERCULOSIS Vaccination is BCG, increasingly hard to access in Aus Widely used throughout the developing world Tb testing is often required for health workers and travellers to some destinations eg Nursing and Medical students in Aus prior to placement, Physiotherapists going to work in UK, many exchange students Testing either with mantoux test or quantiferon gold test BCG available through some travel clinics, RCH and Monash in Melbourne Consider especially for young children with prolonged [3 months] exposure eg VFRs to high risk countries and consider cumulative risk eg 4 weeks every year, not just a single journey. Ideally give 3 months pre travel

49 TRAVELLERS DIARRHOEA The concept of the microbiome, 100 trillion bacteria in the gut [ 10 times the number of human cells in the body] At least distinct species in a mutualistic relationship with the human host We don t tolerate them, we depend on them!

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51 TRAVELLERS DIARRHOEA CLASSIFICATION Mild [tolerable not too interfering with activity] Moderate [distressing and preventing some activity] Severe [incapacitating and includes all dysentery]

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53 TRAVELLERS DIARRHOEA TREATMENT Don't jump straight to antibiotics for all cases Mild cases should be managed expectantly with Oral Rehydration Salts and possibly antidiarrhoeal medication Moderate cases depends on situation, eg other medical illness, isolation and itinerary Travel to some destinations is associated with a heightened risk of acquiring multi drug resistant bacteria and altering your microbiome [15-30%] Antibiotic use doubles that risk [ up to 80%] For South and SE Asia consider azithromycin as the standby antibiotic for severe bacterial gastro, bring from Australia [ up to 80% of medication in some destinations is counterfeit] BUT Use of antibiotics may not prevent the development of Post Infectious Irritable Bowel Syndrome and may increase the risk in some circumstances

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56 PERSISTENT DIARRHOEA POST TRAVEL Persistent and ongoing infection Unmasking previously undiagnosed GI disease eg coeliac disease Post infectious sequelae of the enteric infection Around 10 % of people with travellers diarrhoea develop a persistent illness