Travel and biologic therapy: travel-related infection risk, vaccine response and recommendations

Infection prevention in the immunocompromised traveler due to conditions other than transplantation: a review

This narrative review explores the risks related to infection in immunocompromised travelers due to conditions other than transplantation, and evaluates the evidence behind current prophylactic strategies, including immunizations, antimicrobials, and non-pharmacological interventions, to prevent various infection and how the current evidence applies to this special patient population, from the perspective of a US-based traveler.

Advising the immunocompromised traveller: a review of immunocompromise at The London Hospital for Tropical Diseases Travel Clinic between 1st April 2019 and 30th April 2020

BACKGROUND

Immunocompromised travellers (ICTs) face greater infectious and non-infectious travel-associated risks than their immunocompetent counterparts. Increasing travel and emergence of novel immunosuppressants poses great challenges for travel medicine practitioners to confidently provide up-to-date evidence-based risk management advice and pre-travel care for ICTs.

METHODS

We reviewed the records of ICTs attending the London Hospital for Tropical Diseases (HTD) Travel Clinic between 1st April 2019 and 30th April 2020 with the aim to describe demographic and travel characteristics, type, and severity of immunocompromise, the degree of risk associated with intended travel and evaluate travel advice.

RESULTS

Of the 193 ICTs identified, immunocompromise was due to physiological reasons (42%), chronic infection (17.1%) and immunosuppressive therapy (16.6%). Median age was 38 (range 9 months to 84 years) and male to female ratio 0.75 (83:110). Travel was intended to 80 countries for a median of 16 days (range 2 to 3167), predominantly for leisure (53%), non-medical work (17%) and visiting friends and relatives (12%). Live vaccine safety dominated discussion in the pre-travel consultation. Existing guidelines arguably fell short in dealing with travel risks associated with hyper-specific conditions, targeted immunosuppressants and non-vaccine preventable infections.

CONCLUSIONS

Our cohort represents a wide spectrum of immunocompromise, for whom we arguably need more measurable ways to approach travel-associated risks. We propose prospective qualitative participatory research to inform our unit of the priorities of ICTs in the pre-travel consultation. We further recommend the formation of a repository of specialists and formulary of complex cases to direct subsequent informative systematic review and prospective risk studies.

Leishmania infantum infection after visiting southern Spain in patients on biological treatment; an observational, longitudinal, cohort study

BACKGROUND

Reports of leishmaniasis in immunosuppressed patients after visiting the Mediterranean Basin are becoming increasingly common. Still, awareness of the risk of infection and its clinical manifestations may be insufficient among healthcare professionals in the travellers' home countries.

METHODS

This observational, longitudinal study included 47 patients from Sweden with rheumatic disease and ongoing immunomodulatory treatment, who visited a rehabilitation centre in southern Spain where leishmaniasis is endemic. Patients were evaluated for clinical signs of leishmaniasis at baseline and after three years. Patients with leishmaniasis were followed for 4-5 years. The treatment outcome was assessed by clinical evaluation and determination of the cell-mediated immunological response to Leishmania by a whole blood cytokine release assay.

RESULTS

Seven patients (15%) were diagnosed with leishmaniasis. The median time from exposure to the onset of symptoms was 3 [1-17] months. The median delay between the onset of symptoms and treatment start was 9 [1-12] months. All patients with leishmaniasis responded well to treatment. Only one patient had a relapse, which occurred within the first year.

CONCLUSION

Healthcare professionals need to be aware of the increased risk of leishmaniasis for travellers who are immunosuppressed. Knowledge of the symptoms is crucial for a timely diagnosis and early treatment.

Infections in immunosuppressed travellers with autoimmune inflammatory diseases-a narrative review and advice for clinical practice

The management of autoimmune, inflammatory diseases has been revolutionized by biologic therapies. A beneficial consequence of better disease control is that more patients are well enough to travel the world. There is now a class of traveller, the significantly immunosuppressed person with autoimmune disease, with specific risks and requirements. This review introduces the concept of the pre-travel risk assessment and discusses the major vaccine-preventable and non-vaccine-preventable travel-associated infections. The challenges and controversies around vaccination and immunosuppression are reviewed with advice for clinical practice.

[Travelling with children and adolescents with rheumatic diseases]

Due to the underlying disease and immunosuppressive treatment, pediatric patients with rheumatic diseases are at increased risk for (long distance) travel-related health problems. A pretravel comprehensive consultation is therefore strongly recommended. Whether a child with rheumatic disease is sufficiently fit for travel essentially depends on the disease activity, the age of the child and the intended travel destination. Depending on the level of immunosuppression, the risks for this patient group include (travel-related) infections and the possibility of disease activity flares. Of particular importance is adequate exposure prevention: standard vaccinations should be updated and indications for travel vaccinations evaluated in advance of travelling. In this context, potential contraindications, especially for live vaccines, in the case of specific immunosuppressive treatment should be considered. In the event of travel to malaria endemic areas, the necessity for chemoprophylaxis or stand-by medication must be evaluated but caution is needed regarding potential drug interactions. Detailed education about careful hand, food and contact hygiene is critical. Because photosensitivity may be increased in some rheumatic diseases and/or medications, UV protection is crucial. Barriers (clothes and mosquito nets) and age-appropriate chemical insect repellents should be used to prevent insect-borne diseases. Before start of travel, possibilities for on-site medical help in the event of disease deterioration and/or infection should be evaluated. This should be included in the assessment of the patient's ability to travel. Travelers with rheumatic disease should carry a first aid kit that includes both a sufficient supply of regular antirheumatic medication and supplemental medication in case of a disease flare. Storage conditions must be taken ínto account for some medications. Ultimately, the success of a journey depends on the planning from the perspective of the child with its specific needs.

[Medications when travelling with underlying inflammatory rheumatic disease]

Travelling poses particular challenges for patients with rheumatic diseases. This article provides specific guidance on how best to manage medication while away from home. Besides outlining advice on basic logistic issues, such as the transportation, importation and storage of drugs, the article concentrates on travelling while receiving immunosuppressive therapy and carrying narcotics. Especially when transporting narcotics, travel requires careful planning in advance in close collaboration with physicians on account of the strict and internationally diverse import restrictions on controlled substances. While travelling, all drugs should be kept in the original packaging, including the package insert and stored in carry-on luggage. A specific medical passport may be needed. Immunosuppressive and narcotic drugs require medical certificates issued by the prescribing physician, which may need to be certified by the responsible national agencies. Patients receiving glucocorticoid treatment who travel in or across multiple time zones should also be aware of how the medication impacts and interacts with circadian rhythms so as to optimize the anti-inflammatory effects of the drugs and to avoid unnecessary complications. Given the significant discrepancies in medical care and availability of medication worldwide, the article further stresses the importance of a comprehensive medical kit tailored to the patient's individual medicinal needs. Finally, as immunocompromised travellers are at increased risk of infections, advice is given on the use of anti-infective drugs and chemoprophylaxis for patients travelling to areas in which malaria is endemic as well as on their possible interactions with immunosuppressive treatment.

SARS-CoV-2 vaccination in patients with inflammatory bowel disease

BACKGROUND

The current COVID-19 pandemic, caused by Severe Acute Respiratory Syndrome-Coronavirus-2 (SARS-CoV-2), has drastically impacted societies worldwide. Vaccination against SARS-CoV-2 is expected to play a key role in the management of this pandemic. Inflammatory conditions such as inflammatory bowel disease (IBD) often require chronic immunosuppression, which can influence vaccination decisions.

AIM

This review article aims to describe the most commonly available SARS-CoV-2 vaccination vectors globally, assess the potential benefits and concerns of vaccination in the setting of immunosuppression and provide medical practitioners with guidance regarding SARS-CoV-2 vaccination in patients with IBD.

METHODS

All published Phase 1/2 and/or Phase 3 and 4 studies of SARS-CoV-2 vaccinations were reviewed. IBD international society position papers, safety registry data and media releases from pharmaceutical companies as well as administrative and medicines regulatory bodies were included. General vaccine evidence and recommendations in immunosuppressed patients were reviewed for context. Society position papers regarding special populations, including immunosuppressed, pregnant and breast-feeding individuals were also evaluated. Literature was critically analysed and summarised.

RESULTS

Vaccination against SARS-CoV-2 is supported in all adult, non-pregnant individuals with IBD without contraindication. There is the potential that vaccine efficacy may be reduced in those who are immunosuppressed; however, medical therapies should not be withheld in order to undertake vaccination. SARS-CoV-2 vaccines are safe, but data specific to immunosuppressed patients remain limited.

CONCLUSIONS

SARS-CoV-2 vaccination is essential from both an individual patient and community perspective and should be encouraged in patients with IBD. Recommendations must be continually updated as real-world and trial-based evidence emerges.

Tolerance and humoral immune response to the yellow fever vaccine in sickle cell disease children treated with hydroxyurea: a multicentre prospective study

BACKGROUND

Sickle cell disease (SCD) children are frequent travellers to countries where yellow fever (YF) is endemic, but there are no data regarding the safety and immunogenicity of the vaccine in such children treated with hydroxyurea (HU). The main objective of this study was to compare the tolerance and immune response to YF vaccination in SCD children treated or not with HU.

METHOD

SCD children < 18 years attending the international travel clinics of three large paediatric centres and requiring a first YF vaccination were included in a prospective study. Adverse events were collected 2 weeks after vaccination. YF vaccine antibody titres were measured ~6 months after vaccination.

RESULTS

Among the 52 SCD children vaccinated against YF, 17 (33%) were treated with HU. Only mild adverse events, mainly fever and local reaction, were observed in the HU group with a similar frequency in the non-HU group (57 and 35%, respectively, P = 0.30). YF antibody titres were measured in 15/17 patients in the HU group and 23/35 patients in the non-HU group after a median of 6.0 months (3.5-8.5) following vaccination. The geometric mean of YF antibody titre was similar in both groups. A protective antibody level was observed in 85% of the children in the HU group vs 100% in the non-HU group (P = 0.14), suggesting a lower effectiveness of the vaccine in patients on HU similarly to what has been described in patients on immune suppressive therapy for other vaccines.

CONCLUSION

YF vaccination seems to be safe and efficient in SCD children treated with HU. Considering the potential risk of severe complications in cases of YF while travelling in Africa for those patients, the benefit-to-risk ratio argues for YF vaccination in all SCD children. Control of a protective antibody titre may also be useful to ascertain an adequate response in those treated with HU.

[Travel vaccinations in rheumatic diseases : Specific considerations in children and adults]

Children and adults with rheumatic diseases (RD) have a higher risk to contract infections due to the underlying disease and the frequently necessary immunosuppressive treatment (IT). The quality of life of the majority of patients with RD has remarkably improved due to IT-related reduction of inflammation. Therefore, RD patients usually have an international travel behavior similar to healthy individuals. An investigation indicated that patients with RD and IT have lower travel vaccination rates and are often less well-prepared for their trip in comparison to healthy travelers, even when visiting high risk destinations. As the risk for general and travel-acquired infections is increased for patients with RD with and without IT, pretravel consultations are important. These pretravel consultations should include recommendations addressing travel cancellation, travel modification and travel vaccinations depending on the patient's risk. Travel vaccinations include vaccinations against hepatitis A, typhoid fever, rabies, cholera, meningococcal diseases, tick-bone encephalitis, Japanese encephalitis, seasonal influenza, poliomyelitis and yellow fever. In patients with RD the indications for vaccination depend on the exposure risks, disease severity, individual travel behavior, and possible complications associated with vaccination. In the further evaluation process it is crucial to include the general health condition of the patient, the underlying RD (type and activity), duration and intensity of the IT. In general, live-attenuated vaccines are contraindicated under IT. In contrast, inactivated vaccines may be administered although reduced immunogenicity with the need for antibody measurement, special vaccine schedules or additional booster vaccinations should be considered under IT.

Biological therapy and international travel: A questionnaire survey among Danish patients with rheumatic disease

OBJECTIVE

To describe travel activities, preparations, and health problems encountered by patients with arthritis receiving biological therapy.

METHODS

A travel survey was conducted in a Danish rheumatology outpatient clinic by distribution of a semistructured questionnaire to 300 consecutive patients with arthritis.

RESULTS

Among the 273 (91%) patients returning the questionnaire, a history of traveling outside Denmark was reported by 203 (74%) respondents and outside Europe by 92 (34%). In 81% of the patients, travel activities had not decreased after the initiation of biological treatment. However, 24% reported that they had become more cautious regarding the choice of travel destination. Pre-travel advice was sought by less than one-third of the patients, whereas travel insurance was taken out by 86%, but only half of them had disclosed information about the biological treatment. Treatment was discontinued temporarily while traveling in 26% of patients on subcutaneous biologics. The main reason for discontinuation was concern about transport and storage of medicine. Only 6% of the travelers had experienced health problems, which were of only minor importance.

CONCLUSION

Treatment with biologics seems not to have any major influence on international travel activity among Danish patients with arthritis. Health problems when traveling were of minor importance. However, pre-travel advice issues, including treatment compliance, transport of medicine, and insurance coverage, need to be addressed proactively by the outpatient clinic staff as part of patient consultation.

The immunosuppressed traveler: infection risks with autoimmunity and immunosuppression, vaccinations, and general travel advice

The travel-related infection risks in the significantly immunocompromised traveler are complex and comprise vaccine preventable, vector-borne, and other nonvaccine preventable infections. A thorough risk assessment should be performed before travel and advice sought from relevant specialists. Immunosuppression used to treat autoimmune diseases and their mechanisms of action need particular consideration.This risk assessment needs to take the patient's beliefs and preferences into account. It is also important not to neglect noninfectious travel considerations.

[Travel vaccinations for certain groups of persons]

The number of international travelers has been continuously increasing in recent decades. Among travelers, there are more and more people at an increased risk for acquiring diseases that could be prevented by vaccines or for the development of a severe course of disease. Risk groups in travel medicine are senior travelers, children, pregnant and breast-feeding women, persons with pre-existing medical conditions, and persons who visit their friends and relatives abroad (VFR). Individuals in these groups require attention during pretravel advice consultations, particularly with regards to recommended vaccinations. On the other hand, for some risk groups, particular vaccines cannot be given for safety reasons or because the response to vaccines is reduced. Not all risk groups or each vaccine have sufficient evidence available, so each patient's risks and benefits must be weighed during pretravel consultation. In this article, the particularities for each risk group with respect to pretravel immunization are highlighted.

Vaccines for International Travel

The pretravel management of the international traveler should be based on risk management principles. Prevention strategies and medical interventions should be based on the itinerary, preexisting health factors, and behaviors that are unique to the traveler. A structured approach to the patient interaction provides a general framework for an efficient consultation. Vaccine-preventable diseases play an important role in travel-related illnesses, and their impact is not restricted to exotic diseases in developing countries. Therefore, an immunization encounter before travel is an ideal time to update all age-appropriate immunizations as well as providing protection against diseases that pose additional risk to travelers that may be delineated by their destinations or activities. This review focuses on indications for each travel-related vaccine together with a structured synthesis and graphics that show the geographic distribution of major travel-related diseases and highlight particularly high-risk destinations and behaviors. Dosing, route of administration, need for boosters, and possible accelerated regimens for vaccines administered prior to travel are presented. Different underlying illnesses and medications produce different levels of immunocompromise, and there is much unknown in this discipline. Recommendations regarding vaccination of immunocompromised travelers have less of an evidence base than for other categories of travelers. The review presents a structured synthesis of issues pertinent to considerations for 5 special populations of traveler: child traveler, pregnant traveler, severely immunocompromised traveler, HIV-infected traveler, and traveler with other chronic underlying disease including asplenia, diabetes, and chronic liver disease.

Traveler's diarrhea in children: New insights and existing gaps

The number of children accompanying their parents in international travel is increasing steadily, and with the rising global migration, children more frequently accompany their parents or caregivers for visiting friends or relatives (VFR). As compared to travel for tourism, VFR children are at higher risk of acquiring local diseases, as they more often stay in rural areas in resource-poor locations, have longer periods of visit, are less likely to attend pre-travel consultations, and less frequently adhere to recommended precautions. Travelers's diarrhea (TD) is the most common travel-associated illnesses in children. This review updates the existing knowledge on TD in children, regarding its distinctive epidemiology, risk factors, preventive measures, clinical manifestations, complications, causative microorganisms and management. Despite the limited focused research on pediatric TD, which challenges the formulation of children-oriented evidence-based guidelines, practical recommendations are suggested.

[Traveling with immunodeficiency-Problems and prevention]

Advances in medical care have led to an increasing number of immunocompromised travellers. Travellers with immunodeficiencies have a higher risk of infections and can acquire infectious diseases that are rare in immunocompetent travellers. Of central interest are travellers' diarrhea, diseases of the respiratory tract, tuberculosis and inhalative mycoses as well as diseases transmitted by vectors such as malaria. For every such journey a timely consultation in travel medicine is indicated. First the individual risk must be assessed according to the degree of immunodeficiency. An individual counselling is then related to the itinerary, the travel destination and any activities planned. This information is the basis for an individual set of prophylactic measures with respect to infections and other risks through certain modes of behavior, medication, and vaccinations. Post-travel counselling and evaluation are equally important. This requires physicians experienced in both immunosuppression and travel medicine.

Characteristics and preparation of the last-minute traveler: analysis of vaccine usage in the Global TravEpiNet Consortium

BACKGROUND

Last-minute travellers (LMTs) present challenges for health care providers because they may have insufficient time for recommended vaccinations or pre-travel preparation. Our objective was to obtain a better understanding of LMTs in order to help travel medicine providers develop improved strategies to decrease the number of LMTs and potentially reduce travel-related morbidity.

METHODS

We defined LMTs as travellers with a departure date of 7 days or fewer from the medical encounter. We analysed the characteristics and health preparation of 12 494 LMTs who presented to a network of US clinical practices for pre-travel health advice between January 2009 and December 2015.

RESULTS

LMTs comprised 16% of all travellers. More LMTs than non-LMTs travelled for business or to visit friends and relatives (VFR) (26% vs 16% and 15% vs 8%, respectively; P < 0.0001). More LMTs also travelled for longer than 1 month (27% vs 21%; P < 0.0001) and visited only urban areas (40% vs 29%; P < 0.0001). At least one travel vaccine was deferred by 18% of LMTs because of insufficient time before departure. Vaccines that required multiple vaccinations, such as Japanese encephalitis and rabies, were the most likely to be deferred because of time constraints.

CONCLUSION

Interventions to improve the timing of pre-travel health consultations should be developed, particularly for business and VFR travellers. Recently endorsed accelerated vaccine schedules for Japanese encephalitis and rabies may help some LMTs receive protection against these infections despite late presentation for pre-travel health care.

2018 in review: five hot topics in tropical medicine

The year 2018 heralded many new developments in the field of tropical medicine, including licensure of novel drugs for novel indications, licensure of existing drugs for existing indications but in novel settings, and globalized outbreaks of both vector-borne and zoonotic diseases. We herein describe five top stories in tropical medicine that occurred during 2018, and illuminate the practice-changing development within each story.

S. typhi Vi capsular polysaccharide vaccine-induced humoral immunity in travellers with immunosuppressive therapy for rheumatoid disease

INTRODUCTION

Typhoid fever is a global health problem, causing significant morbidity and mortality. Currently, the most widely used vaccine is the typhoid Vi capsular polysaccharide (Vi-PS) vaccine. While epidemiological studies on its efficacy have been performed in children in endemic countries, there are no efficacy studies evaluating its use in travel medicine. Response to vaccination may differ in travellers receiving immunosuppressive therapy. This study investigates the humoral response to Vi-PS vaccination in travellers receiving immunosuppressive therapy for rheumatoid disease.

METHODS

We recruited patients from the LUMC rheumatology outpatient clinic and travellers from the travel clinic who had previously received Vi-PS vaccination and also immunosuppressive therapy for rheumatoid disease. We analysed blood samples acquired from 42 patients over a period of 3 years. We estimated the length of persistence of protective titres using the survival analysis using multiple cut-off values for protection and measured titre half-life and the influence of immunosuppressive medication on titre half-life using mixed models.

RESULTS

Anti-Vi-PS antibody levels stayed above 10 EU/ml for a mean of 13.3 years, above 15 EU/ml for a mean of 10.1 years and above 20 EU/ml for a mean of 8.6 years after Vi-PS vaccination. Titre half-life was 7.5 years (95% CI 5.0-14.7 years, P < 0.001). No significant influence of medication on titre half-life was found.

CONCLUSION

Both persistence of protective antibody titres and titre half-life are longer than expected based on other studies. This warrants further study in adult volunteers, both in healthy individuals and patients suffering from rheumatoid disease.