Typhoid vaccine: Salmonella bacteria with drug resistance a growing problem. Widespread. Parenteral: single dose IM, booster rec 2 years

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1 INTERNATIONAL TRAVEL General Health Concerns The incidence of VTE on long haul flights is ~0.5% (general population 0.1%). risk factors include flights >8h, older age, obesity, pregnancy, heart disease Prevention: ambulate, leg exercises, hydrate, compression hose, ASA, anticoagulants for high risk patients General Health Concerns Medical conditions: Asthma, Diabetes, etc. Be sure to have adequate medications (in original bottles), test strips, batteries, etc. in case the return home is delayed. Immunocompromised patients may need extra precautions Hepatitis B, Hepatitis C, and HIV/Aids are prevalent in many underdeveloped countries. Tattoos, piercings, sexual contact, etc. carry considerable risk.

2 Vaccinations for International Travel A good source for up to date information: cdc.gov travelers health destination CDC Yellow Book Oxford Press Routine vaccinations: Measles, Mumps, Rubella DPT, Varicella, Polio, Flu Vaccinations usually recommended: Typhoid Hepatitis A Other vaccinations: Hepatitis B, Rabies, Yellow fever, Japanese Encephalitis, Meningitis New vaccinations for Cholera and Malaria Immunization needs depend on prior immunizations, itinerary, duration of visit, likely exposures. Information sources: cdc.gov, WHO website, GlobalTravEpiNet (GTEN) with web based tools for providers and patients based on CDC recommendations. Hepatitis A vaccine: Recommended for all developing countries. One dose at any time prior to travel gives adequate protection but a booster at six months gives long term protection. For patients who refuse vaccination or are allergic, etc., a single dose of IG will give protection for 3 months. Typhoid vaccine: Salmonella bacteria with drug resistance a growing problem. Widespread. Two vaccines available: live oral and parenteral Parenteral: single dose IM, booster rec 2 years on Oral: 4 doses on days 1, 3, 5, 7. Booster in 5 years. Not for children <6 yrs, patients antibiotics, immunocompromised patients

3 Yellow fever vaccine Live virus vaccine One dose gives life long immunity. Repeat dose at 10 years is recommended for travel to high risk areas or for high risk exposure (medical workers, etc.) Serious side effects can occur from the vaccine but are uncommon. Yellow fever is a mosquito borne virus found mostly in Africa and South America. Usually a viral syndrome illness within 3-6 days of exposure. Most cases are mild but 15% can be severe. Countries with risk of yellow fever include Kenya, Congo, Ethiopia, Uganda, Nigeria, Peru, Brazil, Panama, Bolivia, and others. Many countries in Africa require yellow fever vaccination if you are travelling from another country known to have cases. Admission may be refused if you do not have an immunization card documenting yellow fever immunization. Hepatitis B vaccine: Recommended for high risk travelers including medical workers, missionaries, military, long duration visits, medical tourism, potential contact with blood or secretions. Three doses 0, 1 month, 6 months starting 6 months prior to departure. Partial immunity can be achieved with 2 doses but complete the last dose as soon as possible.

4 Rabies vaccination: Vaccine may be recommended if the traveler will be spending a lot of time camping or hiking, having prolonged contact with animals Children may have higher risk than adults Rabies is endemic in most of Asia, Africa, and Central and South America. Cholera vaccine is new (Vaxchora): A live attenuated oral vaccine, one dose at least 10 days prior to travel. Consider for high risk travelers to countries known to have cholera (medical or other mission workers) especially if they may not be able to get adequate treatment rapidly. Generally not needed for average travelers. Cholera is caused by the bacteria Vibrio cholerae. Patients who have had cholera and recover can get it again. Vaccinations Africa: Routine vaccinations Hepatitis A, Typhoid Malaria prophylaxis Hepatitis B, rabies, yellow fever for high risk areas Mexico, Central and South America: Routine, Hepatitis A, Typhoid Haiti, Dominican Republic: Routine, Hepatitis A, Typhoid, Cholera? India: Routine, Hepatitis A, Typhoid, Malaria? Hepatitis B?, Rabies?, Encephalitis? Cuba: Routine, Hepatitis A, Typhoid. Treatment of Cholera Aggressive fluid resuscitation Supportive care Antibiotics - Doxycycline 300mg single dose Tetracycline 500mg q6h Resistance to tetracyclines is increasing Flouroquinolones Cipro, etc. Azithromycin 1000mg single dose Good hygiene, water and food precautions

5 Malaria prophylaxis: Mostly African countries. Risk is increased by length of stay, rural areas, proximity to bodies of water, lower elevations, etc. Medications: Doxycycline: 100mg daily beginning when you enter the risk area. Continue daily while in the risk area and for 30 days after leaving. Adverse reactions include sun sensitivity Mefloquine: 250mg once weekly. Begin 2 weeks before exposure and continue 4 weeks after. Neuropsychiatric adverse reactions may be severe (seizures, psychosis). Malaria prophylaxis (continued) Atovaquone-proguanil (Malarone): 250/100 daily. Begin 1 day before exposure and continue 7 days after exposure Adverse effect of diarrhea, GI upset Malaria vaccination: Trials of the new malaria vaccine are currently underway in several African countries. Mosquito bite prevention: Use DEET, picardin. Other preparations are less effective. Mosquito repellent clothing. Craghoppers, ExOfficio, others Use mosquito nets if available. Sea to Summit sleep sack with Insect Shield? Avoid bodies of water at dusk Zika virus Discovered in 1949 in the Zika Forest of Uganda Usually asymptomatic but can cause severe birth defects (microcephaly) if a pregnant woman becomes infected. Infection can occur from a mosquito bite or sexual contact with an infected person who may be asymptomatic. High risk areas include the Caribbean, Mexico, Central and South America, the Pacific Islands, SE Asia

6 Zika virus recommendations Pregnant women should not travel to high risk areas. Women who travel to high risk areas or have been exposed to Zika (including contact with someone who has recently been to an endemic area) should wait at least 8 weeks before trying to conceive. Men should wait 6 months before trying to conceive Mosquito bite prevention should be used if travel to endemic areas is unavoidable. Strict use of protection for any sexual contact. Blood and urine tests are available Schistosomiasis (Bilharzia) Parasitic blood fluke (worm) which enters the body through skin exposed to infected fresh water. Fresh water snails carry the parasite. Symptoms include rash (swimmers itch), multiple organ system problems, fever, and hematuria with some strains. Diagnosis by serology, many have eosinophilia Importance: avoid swimming or wading in rivers or lakes in Africa. If you swim in a pool, be sure that it is well chlorinated. Trypanosomiasis (Sleeping sickness) Protozoan parasite transmitted by Tsetse flies. Symptoms include headache, progressive neurologic dysfunction, fever, malaise, rash, arthralgias Treatment is complicated and up to 5% die from complications of treatment. Most travel related cases occur in East African game parks. Infection rate is low. Importance: Use insect repellant, mosquito nets if necessary, mosquito repellent clothing also repels flies.

7 Food and Water related Illness Travelers Diarrhea Definition: During travel or within ten days of return from travel 3 or more stools/24hr plus any other symptoms (nausea, fever, vomiting, abdominal pain/cramps, blood in stools, etc.) Causes: Most common causes are Enterotoxigenic Ecoli, Campylobacter (esp SE Asia) Salmonella Immunocompromised hosts may be susceptible to unusual pathogens Treatment of travelers diarrhea May resolve in 3-5 days without specific Rx Fluids, rest, light diet,?imodium If diarrhea persists stool culture, O&P, lab Consider stool amoeba studies, C Difficile, other studies Empiric Rx travelers diarrhea (until culture results are known) Cipro 500 bid X 3 days (or other flouroquinolone) Azithromycin 1000mg single dose ( consider in travel to SE Asia, pregnant women, children) Rifaximin 200tid X 3 days Flagyl 500mg tid if Giardia is suspected Bismuth 2 chew qid X 3 days (stools may turn black) Probiotics?

8 Prophylactic antibiotics Should they be used? Not routinely recommended Contribute to resistant organisms May cause side effects, medication reactions, photosensitivity, yeast infections May interfere with normal flora which may be protective, may take a long time to recover Clinical judgment is necessary to determine when to use (honeymoon, mountain climbing) Bismuth 2 tablets chew 4X day Probiotics effectiveness is uncertain Ciprofloxacin Recently the FDA added a black box warning for Cipro concerning tendonitis and tendon rupture, peripheral neuropathy, CNS effects. Avoid in bronchitis, cystitis, and sinusitis Uptodate still recommends Cipro as the first line treatment for travelers diarrhea. Tendonitis/rupture can be related to flouroquinolone use beginning hours to up to 6 months after use. This is rare but can be debilitating. It is usually linked to other factors including prednisone use, renal failure, advanced age Flouroquinolones should be discontinued if tendonitis or other problems mentioned above occur.

9 Travel Recommendations Diet: If you cant boil it or peel it, don t eat it. Ice cubes can contain pathogens (giardia) Avoid street vendors, salads, sauces, etc. If illness is mild hydration, electrolytes? (Gatorade powder) Imodium, bismuth, rest, supportive care If bloody diarrhea, severe illness, fever, or high risk environment then empiric antibiotics, cultures if possible. May require more aggressive care. Lomotil may cause decrease colon motility which could make the severity of the illness worse. It can help diarrhea but use with caution, especially if significant inflammation is present (fever, WBC s in the stool, bloody diarrhea, significant abdominal pain) Salmonellosis and Typhoid Fever Pathogen and virulence factors Caused by Salmonella enterica serotypes Serotypes Typhi and Paratyphi cause typhoid fever Serotypes Enteritidis and Typhimurium cause salmonellosis Bacteria tolerate acidity of stomach and pass to the intestine Toxins disrupt numerous cellular activities Pathogenesis and epidemiology Typhoid fever is acquired by contaminated food or water. 21 million cases yearly worldwide. 10% fatal Salmonellosis is often acquired by consuming contaminated eggs, poultry, or milk. Salmonellosis and Typhoid Fever Diagnosis, treatment, and prevention Diagnosis made by finding Salmonella in stool Salmonellosis is usually self-limiting. Antibiotics are usually not necessary in uncomplicated illness. Patients may shed the bacteria for weeks after symptoms resolve. Typhoid fever should be treated with antibiotics. Cipro 500mg bid for 7-10 days Cefixime 200mg bid for days Azithromycin 1g po once then 500mg po 7days Prevented with proper hygiene and good food choices

10 Shigellosis Pathogen and virulence factors Caused by four species of Shigella Virulence factors include type III secretion systems and enterotoxins Pathogenesis and epidemiology Pathogen colonizes cells of the small, then large intestine Diagnosis, treatment, and prevention Diagnose by symptoms and presence of Shigella in stool Supportive treatment and administration of antibiotics Cipro 500mg bid X 3 days Azithromycin 500mg qd X 3 days Trimethoprim-sulfamethoxazole DS bid X 5 days Campylobacter Diarrhea Pathogen and virulence factors Caused by Campylobacter jejuni Virulence factors include adhesins, cytotoxins, endotoxin Pathogenesis and epidemiology Virulence factors cause bleeding lesions and inflammation Diagnosis, treatment, and prevention Diagnosis based on signs and symptoms, culture Some cases resolve without treatment Antibiotics of choice: Cipro or Levoquin 750mg qd 3-7 days Azithromycin 500mg qd X 3 days Erythromycin may be an option Prevent with proper hygiene. Poultry, water are sources May resemble ulcerative colitis on sigmoidoscopy Food Poisoning History of acute onset Note: Not everyone eating the same etc.) food will become ill. Factors include size of the inoculum, sensitivity of the GI tract, underlying GI disorders (IBS,

11 Vomiting as presenting symptom Norovirus infects small bowel lining Infectious dose as small as 10 virus particles Passed by fecal oral contact or aerosolized vomitus Good hygiene: Wash hands in warm water and soap then use alcohol based hand cleaners. Don t share food or bathrooms,?quarantine temporarily during outbreaks Oysters may harbor the virus Staphylococcal food poisoning staph toxin builds up in poorly refrigerated food, often potato salad, whipped cream, etc Onset 4 hours after ingestion, lasts <12 hours Diarrhea as the presenting symptom Usually bacteria (toxigenic Ecoli, Salmonella, Shigella, Campylobacter, etc.). Giardia, Amoeba, Cryptosporidia, etc., also present with diarrhea. Norovirus may present with diarrhea but usually vomiting is the primary symptom Bloody diarrhea is a sign of colonic inflammation and a more serious problem, especially if the patient has fever and abdominal pain. Protozoan Diseases Cryptosporidiosis Signs and symptoms Self limited, mild infection in normal hosts Severe watery diarrhea with potentially serious complications in compromised hosts and children Pathogen and pathogenesis Caused by Cryptosporidium parvum Pathogenicity of C. parvum unclear Epidemiology Infection results from drinking contaminated water Diagnosis, treatment, and prevention Treated with fluid and electrolyte replacement Prevented with proper hygiene

12 Oocysts Amebiasis Epidemiology Transmitted by contaminated food or water, contaminated hands, oral/anal intercourse Worldwide distribution, esp underdeveloped countries Most cases are asymptomatic (luminal disease) Invasive disease may occur - factors include E histolytica strain, age, genetic factors, immunocompromised host (steroids, etc.) May infect the liver (abscess), rarely other organs (brain, lung, skin, etc.) Amebiasis (continued) Symptoms Diarrhea (may be bloody, severe), fever, abdominal pain, colitis Diagnosis Stool antigen test serum antigen test usefulness is limited by long term seropositivity from previous amoeba infections Stool O&P exam diagnostic but requires a skilled technician Prevention Good hygiene, safe eating practices, safe sex practices

13 Treatment of amebiasis Hydration, supportive care All cases should be treated, including asymptomatic cases Metronidazole (or similar) followed by a course of paromomycin to eradicate cysts Giardiasis Epidemiology Infection results from ingesting cysts in contaminated water Hikers and campers are at particular risk Diagnosis, treatment, and prevention Diagnosed by microscopic observation of Giardia in stool Treat with metronidazole (adults) or furazolidone (children) May cause diarrhea, gas, bloating, weight loss, malabsorbtion. May cause chronic disease or be asymptomatic. Intestinal villi Ventral adhesive disk Mark left by adhesive disk Dorsal surface

14 Advice to patients Have adequate supplies of medications and medical supplies, including enough to last if the trip is delayed or the medications are lost. Determine if vaccinations are necessary and have enough time to complete them if needed. Use good judgment for food choices. If you cant peel it or cook it there is some risk. Use sun screen, mosquito bite prevention Use bottled water exclusively (including brushing your teeth). Avoid ice cubes unless made with bottled water or deep well water. General Approach Food poisoning Vomiting supportive care Diarrhea supportive care, Imodium If persists or worsens then culture, O&P,?antibiotics,?refer Travelers diarrhea see algorithms Bloody diarrhea culture, O&P,?antibiotics, refer? Immigrants may have multiple gi tract pathogens and some or all may be relatively asymptomatic. This complicates evaluations. We need to be aware that special testing may be needed and hygiene at home is important to prevent spread of disease. Food poisoning (continued) Good hand washing warm water and soap. Alcohol based hand cleaners may not be enough Inflammatory diarrhea should be investigated and may require antibiotics Note: antibiotics are not recommended for Enterohemorhagic Ecoli (shiga toxin producing) since hemolytic uremic syndrome may occur (esp in children) Note that IBD may present as an acute illness and mimic infectious diarrhea Some cases of infectious diarrhea are reportable

15 Algorithm for deciding whether empirical treatment of infectious diarrhea is required.3,5,12 *For nonbloody diarrhea with a history of travel, antibiotic use only reduces symptoms by 1 2 days and is associated with side effects; such treatment may not be ju by Canadian Medical Association Algorithm for deciding when testing is required in patients who present with infectious diarrhea.3 5 Note: C. difficile = Clostridium difficile, EIA = enzyme immunoassay.