Fever in returned travelers: review of hospital admissions for a 3-year period

Travel-related respiratory symptoms and infections in travellers (2000-22): a systematic review and meta-analysis

BACKGROUND

Respiratory tract infections (RTIs) are common in travellers due to the year-round or seasonal presence of respiratory pathogen and exposure to crowded environments during the itinerary. No study has systematically examined the burden of RTI infections among travellers. The aim of this systematic review and meta-analysis is to evaluate the prevalence of RTIs and symptoms suggestive of RTIs among travellers according to risk groups and/or geographic region, and to describe the spectrum of RTIs.

METHODS

The systematic review and meta-analysis was registered in PROSPERO (CRD42022311261). We searched Medline, Embase, Scopus, Cochrane Central, Web of Science, Science Direct and preprint servers MedRxiv, BioRxiv, SSRN and IEEE Xplore on 1 February 2022. Studies reporting RTIs or symptoms suggestive of RTIs in international travellers after 1 January 2000 were eligible. Data appraisal and extraction were performed by two authors, and proportional meta-analyses were used to obtain estimates of the prevalence of respiratory symptoms and RTIs in travellers and predefined risk groups.

FINDINGS

A total of 429 articles on travellers' illness were included. Included studies reported 86 841 symptoms suggestive of RTIs and 807 632 confirmed RTIs. Seventy-eight percent of reported respiratory symptoms and 60% of RTIs with available location data were acquired at mass gatherings events. Cough was the most common symptom suggestive of respiratory infections, and the upper respiratory tract was the most common site for RTIs in travellers. The prevalence of RTIs and respiratory symptoms suggestive of RTIs were 10% [8%; 14%] and 37% [27%; 48%], respectively, among travellers. Reporting of RTIs in travellers denoted by publication output was found to correlate with global waves of new respiratory infections.

INTERPRETATION

This study demonstrates a high burden of RTIs among travellers and indicates that travellers' RTIs reflect respiratory infection outbreaks. These findings have important implications for understanding and managing RTIs among travellers.

Tropical infections as occupational diseases among young volunteers in social projects

PURPOSE

The trend of volunteering overseas has increased tremendously over the last decade. Volunteers often go to regions where they are exposed to the risk of tropical infections like malaria, dengue, typhoid fever and schistosomiasis. Health assessments have shown a high occurrence of tropical infections among young volunteers. Such tropical infections are notifiable in Germany, as they are covered by a separate branch of the social insurance system. However, there is still limited data on systematical improvement of medical prevention and health care for volunteers.

METHODS

This retrospective study included 457 cases with a diagnosis for a tropical infection or typhoid fever from January 2016 to December 2019. Data sets were anonymised and then analysed with descriptive statistics first. Cases of volunteers sent abroad by "Weltwärts" were compared to cases of aid workers sent to non-industrial countries.

RESULTS

A high occurrence of tropical infections as occupational diseases has been shown for volunteers compared to other (mostly older) aid workers being sent to tropical regions. The risk of acquiring a tropical infection was significantly higher in Africa compared to other tropical regions. Cases of malaria were reported significantly more often among the group of volunteers than among aid workers during the period under review. Medical check-ups after travel were rare among volunteers.

CONCLUSIONS

Data imply a disproportionate risk for malaria in Africa with a higher risk of acquiring malaria tropica in Sub-Saharan regions. Region-specific risks need to be addressed in training seminars in order to raise awareness among young volunteers before travel. Medical examinations after travel should be mandatory and specific to a particular region.

SARS-CoV-2 and Plasmodium falciparum Co-Infection in a Returning Traveler

Since December 2019, the Coronavirus Disease 2019 (COVID-19) pandemic has become a non-neglectable context for the whole healthcare system. Under the background of COVID-19, the detection and diagnosis of malaria cases are under challenge. Here, we reported a COVID-19 and malaria co-infection traveler who has a long living history in Cameroon. The case was administered with dihydroartemisinin and piperaquine tablets for malaria, Lopinavir and Ritonavir tablets, Arbidol, recombinant human interferon α-2b and Compound Maxing Yifei mixture for COVID-19, and Zolpidem Tartrate tablets, Diazepam, Paroxetine Hydrochloride tablets, Thymosin α1, and Lianhua Qinwen Jiaonang during the second hospitalization of the patient since the patient has a certain level of anxiety and insomnia with no evidence of inflammatory reactions. After being tested negative two times for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) in 48 h, the patient met China's COVID-19 discharge standards and was discharged with stable vital signs and mental state. Since most countries in the sub-Saharan region have a fragile health system, co-infection for both Plasmodium and SARS-CoV-2 may not be uncommon, and raise a challenge in diagnosis, treatment, and prevention for both diseases. We add to the literature on co-infection of P. falciparum malaria and COVID-19 and offer operational advice on diagnosis, prevention, and treatment for the co-infection.

Malaria diagnostic methods with the elimination goal in view

Malaria control measures have been in use for years but have not completely curbed the spread of infection. Ultimately, global elimination is the goal. A major playmaker in the various approaches to reaching the goal is the issue of proper diagnosis. Various diagnostic techniques were adopted in different regions and geographical locations over the decades, and these have invariably produced diverse outcomes. In this review, we looked at the various approaches used in malaria diagnostics with a focus on methods favorably used during pre-elimination and elimination phases as well as in endemic regions. Microscopy, rapid diagnostic testing (RDT), loop-mediated isothermal amplification (LAMP), and polymerase chain reaction (PCR) are common methods applied depending on prevailing factors, each with its strengths and limitations. As the drive toward the elimination goal intensifies, the search for ideal, simple, fast, and reliable point-of-care diagnostic tools is needed more than ever before to be used in conjunction with a functional surveillance system supported by the ideal vaccine.

COVID-19 and blood groups: A six-months observational study in Ferrara, Italy

The current literature still gives a little information about the relationships between the ABO blood group system and the immune response to the virus or the different disease outcomes. Hypothesizing the presence of a predisposition by some blood groups to COVID-19, we searched for differences between patients towards the different outcomes of disease.We enrolled 330 inpatients with a diagnosis of COVID-19, determining both their ABO blood group system and Rh factor, collecting demographic, clinical and laboratory data. We searched for relationships with COVID-19 outcomes within an observation period of 180 days (Intensification of Care - IoC, Inhospital death, 180-days mortality). The most frequent ABO blood group was A (45.8%); a minor part was represented by group O (38.8%), B (11.5%), AB (3.9%). As for the Rh factor, 86.7% of patients were Rh-positive. There were no significant differences between blood groups and Rh factors as for age, length of hospital stays (LoS), or Charlson Comorbidity Index (CCI), nor we found significant relationships between the ABO groups and COVID-19 outcomes. A significant relation was found between AB group and IoC (p=0.03) while as for the Rh factor, the patients with Rh factor positive died with less frequency during the stay (p=0.03). Cox regression analyses showed substantial differences in the survival functions concerning the Rh factors. The Rh factor seems to be involved in the 180-day prognosis. The survival functions of patients with Rh factor positive show, in fact, significantly better curves when compared to those with Rh factor negative.

A descriptive analysis of dengue in Peace Corps Volunteers, 2000-2019

BACKGROUND

Peace Corps Volunteers (PCVs) are a unique expatriate population at risk for dengue. Previous studies examined travelers or lacked demographic information about expatriates. We examined dengue incidence among PCVs before and after deployment of an electronic medical record (EMR) to assess temporal and demographic factors.

METHODS

Dengue cases within Peace Corps' Epidemiologic Surveillance System from 2000 to 2019 were identified using a standard case definition, and two timeframes were compared: pre-EMR 2000-2015 and post-EMR 2016-2019.

RESULTS

Annual infections occurred in a roughly 3-year cyclic pattern from 2007 to 2019. Incidence rate decreased from 1.35 cases per 100 dengue Volunteer-years (95% CI 1.28-1.41) in 2000-2015 to 1.25 cases (95% CI 1.10-1.41) in 2016-2019. Among PCVs who served from 2016 to 2019, the majority of infections occurred in females and 20-29 year olds, and 7% were medically evacuated. Among PCVs who served from 2015 to 2019, 21% were hospitalized in-country.

CONCLUSIONS

Among PCVs, a non-significant decrease in dengue incidence occurred from 2000-2015 to 2016-2019. Annual infection rates peaked every three years, offering opportunities for targeted prevention efforts. Dengue infection in PCVs appears to mimic the overall demographic of Peace Corps. Expatriates like PCVs are at an increased risk for dengue infection compared to short-term travelers.

Dermatologic Manifestations of Tick-borne Diseases in Travelers

Purpose of Review

International and domestic travelers may acquire a wide variety of infectious diseases transmitted by exposure to insects. Exposure to ticks may be associated with systemic infections clinically suspected through skin and soft tissue manifestations along with fever, myalgia, headache, and other related symptoms. Cutaneous lesions may include eschars at the site of initial contact, maculopapular rashes, or others as the result of systemic dissemination of viral, Rickettsial, parasitic, and protozoan infections acquired by exposure to different types of ticks.

Recent findings

Ticks represent the second most common global vector of transmission of infectious diseases to humans after mosquitoes. In some endemic regions, ticks are the most important vector of transmission of a great variety of infectious pathogens including protozoan (Babesia spp.), viral (Coltivirus), rickettsia, and bacterial infections (Francisella tularensis). With increasing international travel, different tick-borne diseases continue to emerge and being identified.

Summary

Identifying the cutaneous signs associated with tick-borne diseases is crucial to clinically suspect the diagnosis of a specific tick-borne illness. Minimizing the exposure to ticks during domestic or international travel represents the most important intervention to reducing the risk of tick-borne illnesses.

Aetiology of fever in returning travellers and migrants: a systematic review and meta-analysis

BACKGROUND

Numerous publications focus on fever in returning travellers, but there is no known systematic review considering all diseases, or all tropical diseases causing fever. Such a review is necessary in order to develop appropriate practice guidelines.

OBJECTIVES

Primary objectives of this review were (i) to determine the aetiology of fever in travellers/migrants returning from (sub) tropical countries as well as the proportion of patients with specific diagnoses, and (ii) to assess the predictors for specific tropical diseases.

METHOD

Embase, MEDLINE and Cochrane Library were searched with terms combining fever and travel/migrants. All studies focusing on causes of fever in returning travellers and/or clinical and laboratory predictors of tropical diseases were included. Meta-analyses were performed on frequencies of etiological diagnoses.

RESULTS

10 064 studies were identified; 541 underwent full-text review; 30 met criteria for data extraction. Tropical infections accounted for 33% of fever diagnoses, with malaria causing 22%, dengue 5% and enteric fever 2%. Non-tropical infections accounted for 36% of febrile cases, with acute gastroenteritis causing 14% and respiratory tract infections 13%. Positive likelihood ratios demonstrated that splenomegaly, thrombocytopenia and hyperbilirubinemia were respectively 5-14, 3-11 and 5-7 times more likely in malaria than non-malaria patients. High variability of results between studies reflects heterogeneity in study design, regions visited, participants' characteristics, setting, laboratory investigations performed and diseases included.

CONCLUSION

Malaria accounted for one-fifth of febrile cases, highlighting the importance of rapid malaria testing in febrile returning travellers, followed by other rapid tests for common tropical diseases. High variability between studies highlights the need to harmonize study designs and to promote multi-centre studies investigating predictors of diseases, including of lower incidence, which may help to develop evidence-based guidelines. The use of clinical decision support algorithms by health workers which incorporate clinical predictors, could help standardize studies as well as improve quality of recommendations.

Malaria and COVID-19: unmasking their ties

The incidence and mortality of COVID-19, according to the World Health Organization reports, shows a noticeable difference between North America, Western Europe, and South Asia on one hand and most African countries on the other hand, especially the malaria-endemic countries. Although this observation could be attributed to limited testing capacity, mitigation tools adopted and cultural habits, many theories have been postulated to explain this difference in prevalence and mortality. Because death tends to occur more in elders, both the role of demography, and how the age structure of a population may contribute to the difference in mortality rate between countries were discussed. The variable distribution of the ACEI/D and the ACE2 (C1173T substitution) polymorphisms has been postulated to explain this variable prevalence. Up-to-date data regarding the role of hydroxychloroquine (HCQ) and chloroquine (CQ) in COVID-19 have been summarized. The article also sheds lights on how the similarity of malaria and COVID-19 symptoms can lead to misdiagnosis of one disease for the other or overlooking the possibility of co-infection. As the COVID-19 pandemic threatens the delivery of malaria services, such as the distribution of insecticide-treated nets (ITNs), indoor residual spraying, as well as malaria chemoprevention there is an urgent need for rapid and effective responses to avoid malaria outbreaks.

Non-vaccine-Preventable Infections

There are many potentially serious infections that may pose a risk to travellers for which no vaccines are available. Following discussions on vaccines, malaria prevention and travellers’ diarrhoea at the consultation, the travel-medicine practitioner should identify other infectious risks that may apply to the traveller, whether because of destination/s and duration of travel, occupational or other activities, or individual susceptibility. Information should be provided about these infections, their relevance, modes of transmission and methods of prevention, or the traveller should be referred to an authoritative source of information. In this chapter, advice will be given on both destination- and activity-related infections. The risk, distribution, clinical features and methods of prevention of a number of specific infections for which no vaccines are available are then outlined. This includes information on emerging viral infections such as Zika, MERS, Ebola and Chikungunya.

Respiratory Infections

Respiratory tract infections (RTIs) are a common health problem of international travelers. Travelers may be at increased risk of RTIs due to travel itself (mingling and close quarters in airports, airplanes, cruise ships, and hotels), and due to unique exposure at travel destinations. The clinical spectrum of RTIs in travelers is broad and includes upper RTIs, pharyngitis, otitis, laryngitis, bronchitis, and pneumonia. Most travelers who acquire an RTI only develop mild disease, and only a minority seek medical attention. All travelers should be up to date on any indicated vaccines based on age and medical condition that prevent RTIs, including influenza, measles, pneumococcal diseases, Haemophilus influenzae b, Neisseria meningitidis, diphtheria, and pertussis.

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Respiratory tract infections (RTIs) are among the most common illnesses reported by travelers. Most RTIs are viral, involve the upper respiratory tract, and do not require specific diagnosis or treatment.

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Influenza is often considered the most important travel-related infection. Travelers play an integral role in the yearly and global spread of influenza.

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Lower RTIs, including pneumonia, often require antimicrobial therapy.

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High-risk groups such as infants, small children, the elderly, and subjects with chronic tracheobronchial or pulmonary disease are at increased risk of developing severe clinical consequences should infection occur. All international travelers should be immunized for seasonal influenza unless otherwise contraindicated, and travelers should be instructed in hand hygiene and sneeze and cough hygiene.

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All travelers should be up to date on any indicated vaccines that prevent RTIs, including measles, pneumococcal diseases, Haemophilus influenzae b (Hib), meningococcal disease, diphtheria, and pertussis.

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Travelers may be at increased risk of geographically restricted RTIs, and clinicians should be familiar with the major manifestations of these illnesses.

Rickettsioses in Denmark: A retrospective survey of clinical features and travel history

Rickettsia spp. can be found across the globe and cause disease of varying clinical severity, ranging from life-threatening infections with widespread vasculitis to milder, more localized presentations. Vector and, to some degree, reservoir are hematophagous arthropods, with most species harboured by ticks. In Denmark, rickettsiae are known as a cause of imported travel-related infections, but are also found endemically in ticks across the country. Data are, however, lacking on the geographical origin and clinical features of diagnosed cases. In this study, we have examined the travel history and clinical features of two groups of patients; 1) hospital-patients diagnosed with rickettsioses in the years 2010-2015 and 2) patients from primary health care (PHC) centers in Denmark having demonstrated anti-rickettsia antibodies in the years 2012-2015. The patients were identified using the Danish National Patient Registry (DNPR) and through the serological database at the State Serum Institute, where the laboratory diagnosis of rickettsioses is currently centralized. Data were collected for 86 hospital patients and 26 PHC center patients by reviewing hospital medical records and performing telephone interviews with PHC centers. Of the hospital patients, 91% (78/86) had a history of international travel 14 days prior to symptom start, with most having imported their infection from southern Africa, South Africa in particular (65%), and presenting with a clinical picture most compatible with African tick-bite fever caused by R. africae. Only two patients presented with a CRP > 100 mg/L and no mortalities were reported. At the PHC centers, most patients presented with mild flu-like symptoms and had an unknown (50%) or no history (19%) of international travel, raising the possibility of endemic rickettsioses. In view of our findings, rickettsioses do not appear to constitute a major public health problem in Denmark, with most cases being imported infections and potential endemic cases presenting as mild infections.

Redefining priorities towards graded travel-related infectious disease research

Our knowledge of the health problems and infections encountered by international travellers has evolved considerably in the past decades. The growth of global networks such as the GeoSentinel Surveillance network, TropNet Europe, EuroTravNet and networks based in North America have provided valuable information on the frequency of a wide array of travel-related diseases and accidents, including details on the destination of travel and trends over time. The information gained from these network studies has provided important data for the practice of travel medicine and in some instances for the development of practice guidelines. However, network data due to a lack of denominators usually cannot serve as a basis for a GRADE approach to guideline development. Although epidemiological network studies will continue to serve an important role in travel medicine we encourage an additional strong focus towards translational scientific research questions and towards the broader use of novel techniques to obtain more accurate epidemiological analyses to address the many unanswered questions in our field.

Risk activities and pre-travel health seeking practices of notified cases of imported infectious diseases in Australia

BACKGROUND

Travellers are at risk of acquiring infectious diseases during travel, with risks differing by destination, travel and traveller characteristics. A pre-travel health consultation may minimize this risk. However, uptake of pre-travel health advice remains low. We investigated pre-travel health preparations and disease-specific risk behaviours among notified cases of selected travel-associated infectious diseases imported into Australia.

METHODS

Prospective enhanced surveillance of notified cases of typhoid, paratyphoid, measles, hepatitis A, hepatitis E, malaria and chikungunya was conducted in two Australian states between February 2013 and January 2014. Details of pre-travel health preparation and disease-specific risk behaviours were collected.

RESULTS

Among 180 cases associated with international travel, 28% were <18 years, 65% were VFR travellers and 22% were frequent travellers, having travelled ≥5 times in the past 5 years. 25% had sought pre-travel advice from a healthcare provider, and 16% reported a pre-travel vaccine. Seeking pre-travel health advice did not differ by immigrant status ( P  = 0.22) or by reason for travel ( P  = 0.13) but was more commonly sought by first time travellers ( P  = 0.03). Travellers visiting friends and relatives were more likely to report at-risk activities of brushing teeth with tap water ( P  < 0.001) and eating uncooked food ( P  = 0.03) during travel compared to other travellers.

CONCLUSIONS

Pre-travel health advice seeking practices and vaccine uptake was suboptimal among cases of notified disease. The results of this study highlight the need for a better understanding of barriers to pre-travel health seeking, particularly among high risk travellers, to reduce the importation of infectious diseases into Australia.

Severe interstitial pneumonia due to murine typhus in a patient returning from Bali

Murine typhus has been increasingly reported as a cause of fever in returning travelers from Southeast Asia. We report a case of a previously healthy traveler returning from Bali with an non-specific febrile illness which quickly progressed to a severe form of interstitial pneumonia. After a careful epidemiological evaluation and laboratory analysis, murine typhus was diagnosed.

Dengue

Dengue is one of the most important mosquito-borne viral infections caused by single-stranded RNA virus that are transmitted by the Aedes aegypti and Aedes albopictus mosquito species. Dengue is endemic in over 140 countries in Asia, the USA, the Eastern Mediterranean, and Africa. The World Health Organization (WHO) estimated that there are more than 2.5 billion people—mainly occurs in children living in tropical and subtropical countries—at risk of dengue infection with one or more dengue viruses. There are estimated nearly 100 million symptomatic dengue infections occurring worldwide annually, nearly 75% in Asia and the Western Pacific region [1]. During the past decades, the outbreaks of dengue infection have been reported throughout the world with increased severity. Ecologic and demographic changes are considered to be the contributing factors to the emergence of dengue infection in the past decades. Dengue has expanded into new countries and into urban settings associated with increased distribution of A. aegypti, population growth, urbanization, development of slums, migration of population, movement of dengue virus by infected travelers, trade development, and improved diagnostic capabilities in medical practice [2, 3]. Increased transmission of dengue virus in tropical urban areas has been created by substandard housing and crowding as well as deterioration in water, sewer, and waste management systems, all of which are intimately associated with unplanned urbanization [4–7]. So it is likely that dengue will expand its geographic reach and become an increasing burden on health resources in affected areas during the next decade. An effective vector-control management is the only means to reduce dengue infection in endemic areas. Because vector control has achieved only limited success so far in reducing the transmission of dengue, the usage of effective dengue vaccine in target population along with the preventive measures already used such as raising public awareness may be the means to effectively control of this disease in endemic area [8].

Spectrum of Viral Pathogens in Blood of Malaria-Free Ill Travelers Returning to Canada

Malaria is the most common specific cause of fever in returning travelers, but many other vectorborne infections and viral infections are emerging and increasingly encountered by travelers. We documented common and emerging viral pathogens in malaria-negative specimens from ill travelers returning to Canada. Anonymized, malaria-negative specimens were examined for various viral pathogens by real-time PCR. Samples were positive for herpes simplex viruses 1 or 2 (n = 21, 1.6%), cytomegalovirus (n = 4, 0.3%), Epstein-Barr virus (n = 194, 14.9%), dengue virus types 1-4 (n = 27, 2.1%), chikungunya virus (n = 5, 0.4%), and hepatitis A virus (n = 12, 0.9%). Travel-acquired viral pathogens were documented in >20% of malaria-negative specimens, of which 2.5% were infected with dengue and chikungunya viruses. Our findings support the anecdotal impression that these vectorborne pathogens are emerging among persons who travel from Canada to other countries.

Low and declining attack rates of imported typhoid fever in the Netherlands 1997-2014, in spite of a restricted vaccination policy

Background

Typhoid fever mainly occurs in (sub) tropical regions where sanitary conditions remain poor. In other regions it occurs mainly among returning travelers or their direct contacts. The aim of this study was to evaluate the current Dutch guidelines for typhoid vaccination.

Method

Crude annual attack rates (AR) per 100,000 Dutch travelers were calculated during the period 1997 to 2014 by dividing the number of typhoid fever cases by the estimated total number of travelers to a specific country or region. Regions of exposure and possible risk factors were evaluated.

Results

During the study period 607 cases of typhoid fever were reported. Most cases were imported from Asia (60%). Almost half of the cases were ethnically related to typhoid risk regions and 37% were cases visiting friends and relatives. The overall ARs for travelers to all regions declined significantly. Countries with the highest ARs were India (29 per 100,000), Indonesia (8 per 100,000), and Morocco (10 per 100,000). There was a significant decline in ARs among travelers to popular travel destinations such as Morocco, Turkey, and Indonesia. ARs among travelers to intermediate-risk areas according to the Dutch guidelines such as Latin America or Sub-Saharan Africa remained very low, despite the restricted vaccination policy for these areas compared to many other guidelines.

Conclusion

The overall AR of typhoid fever among travelers returning to the Netherlands is very low and has declined in the past 20 years. The Dutch vaccination policy not to vaccinate short-term travelers to Latin-America, Sub-Saharan Africa, Thailand and Malaysia seems to be justified, because the ARs for these destinations remain very low. These results suggest that further restriction of the Dutch vaccination policy is justified.

Travel-related illness at a tertiary care hospital in Osaka, Japan

We analyzed the travel-related health problems in persons returning to Japan from overseas. Data were extracted retrospectively for all patients visiting the infectious diseases department of Osaka City General Hospital, Osaka, Japan, between July 2012 and September 2013. There were 209 sick returning travelers during the period of the study. The median age of the subjects was 34.3 years, and the subjects consisted of 133 tourists (63.6%), 39 business travelers (18.7%), 17 expatriates (8.1%), 14 volunteer workers (6.7%), and four persons who visited friends and relatives (1.9%). The most visited destinations were Asia (n=162, 77.5%), including East Asia (n=26, 12.4%), Southeast Asia (n=116, 55.5%), South Asia (n=25, 12.0%), Central Asia (n=3, 1.4%), and Africa (n=30, 14.3%). The most commonly diagnosed diseases were gastrointestinal tract infection (n=81, 38.8%), dengue fever (n=26, 12.4%), and animal bites (n=26, 12.4%). Twenty-nine patients (13.8%) were hospitalized, mainly for dengue fever and gastrointestinal tract infection.

Evaluation of a programme for 'Rapid Assessment of Febrile Travelers' (RAFT): a clinic-based quality improvement initiative

BACKGROUND

Fever in the returned traveller is a potential medical emergency warranting prompt attention to exclude life-threatening illnesses. However, prolonged evaluation in the emergency department (ED) may not be required for all patients. As a quality improvement initiative, we implemented an algorithm for rapid assessment of febrile travelers (RAFT) in an ambulatory setting.

METHODS

Criteria for RAFT referral include: presentation to the ED, reported fever and travel to the tropics or subtropics within the past year. Exclusion criteria include Plasmodium falciparum malaria, and fulfilment of admission criteria such as unstable vital signs or significant laboratory derangements. We performed a time series analysis preimplementation and postimplementation, with primary outcome of wait time to tropical medicine consultation. Secondary outcomes included number of ED visits averted for repeat malaria testing, and algorithm adherence.

RESULTS

From February 2014 to December 2015, 154 patients were seen in the RAFT clinic: 68 men and 86 women. Median age was 36 years (range 16-78 years). Mean time to RAFT clinic assessment was 1.2±0.07 days (range 0-4 days) postimplementation, compared to 5.4±1.8 days (range 0-26 days) prior to implementation (p<0.0001). The RAFT clinic averted 132 repeat malaria screens in the ED over the study period (average 6 per month). Common diagnoses were: traveller's diarrhoea (n=27, 17.5%), dengue (n=12, 8%), viral upper respiratory tract infection (n=11, 7%), chikungunya (n=10, 6.5%), laboratory-confirmed influenza (n=8, 5%) and lobar pneumonia (n=8, 5%).

CONCLUSIONS

In addition to provision of more timely care to ambulatory febrile returned travellers, we reduced ED bed-usage by providing an alternate setting for follow-up malaria screening, and treatment of infectious diseases manageable in an outpatient setting, but requiring specific therapy.

Malaria and other febrile diseases among travellers: the experience of a reference centre located outside the Brazilian Amazon Region

BACKGROUND

Malaria is endemic in countries located in tropical and sub-tropical regions. The increasing flow of domestic and international travellers has made malaria a relevant health problem even in non-endemic regions. Malaria has been described as the main diagnosis among travellers presenting febrile diseases after returning from tropical countries. In Brazil, malaria transmission occurs mainly in the Amazon region. Outside this area, malaria transmission is of low magnitude.

METHODS

This cross-sectional study aimed to describe the experience in the diagnosis of malaria in a reference centre located outside the Brazilian Amazon Region, emphasizing the differences in clinical and laboratory markers between cases of malaria and those of other febrile diseases (OFD). Medical charts from adult patients (≥18 years) who underwent a thick smear test (TST) for malaria, between January 2001 and December 2014, were retrospectively reviewed.

RESULTS

A total of 458 cases referred to perform the TST were included. Malaria was diagnosed in 193 (42 %) episodes. The remaining 265 episodes (58 %) were grouped as OFD. The majority of malaria episodes were acquired in the Brazilian Amazon Region. The median time between the onset of symptoms and the TST was 7 days. Only 53 (11.5 %) episodes were tested within the first 48 h after symptom onset. Comparing malaria with OFD, jaundice, nausea, vomiting, and reports of fever were more prevalent in the malaria group. Low platelet count and elevated bilirubin levels were also related to the diagnosis of malaria.

CONCLUSIONS

The results indicate that outside the endemic area travellers presenting febrile disease suspected of being malaria underwent diagnostic test after considerable delay. The reporting of fever combined with a recent visit to an endemic area should promptly evoke the hypothesis of malaria. In these cases, specific diagnostic tests for malaria should be a priority. For cases that jump this step, the presence of elevated bilirubin or thrombocytopaenia should also indicate a diagnosis of malaria.

Illness in the Returned International Traveler

Familiarity with the distribution, mode of transmission, and risk factors for acquisition of illnesses commonly transmitted to travelers to low-income nations can help guide clinicians in their work-up of an ill returned traveler. The 3 most common categories of illness in returned international travelers are gastrointestinal illness, fever, and dermatoses. Diarrhea is the most common illness reported in returned international travelers. Fever is a marker of a potentially significant illness; work-up of the ill febrile returned traveler should be conducted promptly.

Management of septic shock and severe infections in migrants and returning travelers requiring critical care

During the past decade, global human movement created a virtually "borderless world". Consequently, the developed world is facing "forgotten" and now imported infectious diseases. Many infections are observed upon travel and migration, and the clinical spectrum is diverse, ranging from asymptomatic infection to severe septic shock. The severity of infection depends on the etiology and timeliness of diagnosis. While assessing the etiology of severe infection in travelers and migrants, it is important to acquire a detailed clinical history; geography, dates of travel, places visited, type of transportation, lay-overs and intermediate stops, potential exposure to exotic diseases, and activities that were undertaken during travelling and prophylaxis and vaccines either taken or not before travel are all important parameters. Tuberculosis, malaria, pneumonia, visceral leishmaniasis, enteric fever and hemorrhagic fever are the most common etiologies in severely infected travelers and migrants. The management of severe sepsis and septic shock in migrants and returning travelers requires a systematic approach in the evaluation of these patients based on travel history. Early and broad-spectrum therapy is recommended for the management of septic shock comprising broad spectrum antibiotics, source control, fluid therapy and hemodynamic support, corticosteroids, tight glycemic control, and organ support and monitoring. We here review the diagnostic and therapeutic routing of severely ill travelers and migrants, stratified by the nature of the infectious agents most often encountered among them.

Fever of unknown origin: a clinical approach

Fevers of unknown origin remain one of the most difficult diagnostic challenges in medicine. Because fever of unknown origin may be caused by over 200 malignant/neoplastic, infectious, rheumatic/inflammatory, and miscellaneous disorders, clinicians often order non-clue-based imaging and specific testing early in the fever of unknown origin work-up, which may be inefficient/misleading. Unlike most other fever-of-unknown-origin reviews, this article presents a clinical approach. Characteristic history and physical examination findings together with key nonspecific test abnormalities are the basis for a focused clue-directed fever of unknown origin work-up.

A fatal case of primary dengue infection with myocarditis and cerebral oedema

With dengue fever emerging as a global health problem and more Australians travelling to endemic areas, imported dengue infection is on the rise and clinicians need to remain vigilant. Primary cardiac and neurologic involvement in dengue infection has been rarely described in the medical literature and the pathophysiology is poorly understood. A rare and fatal case of primary dengue infection in a 34-yearold woman who returned from Papua New Guinea is reported; the unusual features of this case include severe primary dengue infection, myocarditis, and acute cerebral oedema resulting in death. This case demonstrates that severe atypical manifestations and fatality can occur with primary dengue infection.

Acute kidney injury in dengue virus infection

Background

Dengue is a growing public health problem in Pakistan and acute kidney injury (AKI) is one of the least studied complications of dengue virus infection (DVI). The aim of this study was to determine the frequency, severity and predictors of AKI in patients with DVI and to study the impact of AKI on the length of hospital stay and mortality.

Methods

We retrospectively reviewed medical records of patients aged ≥14 years hospitalized with a primary diagnosis of DVI at Aga Khan University Hospital Karachi between January 2008 and December 2010. Binary logistic regression models were constructed to identify factors associated with the development of AKI and to study the impact of AKI on hospital stays of more than 3 days.

Results

Out of 532 patients, AKI was present in 13.3% (71/532). Approximately two-thirds (64.8%) of these patients had mild AKI and a third (35.2%) had moderate to severe AKI. Independent predictors for AKI were male gender [odds ratio (OD) 4.43; 95% CI 1.92–10.23], presence of dengue hemorrhagic and dengue shock syndrome (DSS, OD 2.14; 95% CI 1.06–4.32), neurological involvement (OD 12.08; 95% CI 2.82–51.77) and prolonged activated partial thromboplastin time (aPTT, OD 1.81; 95% CI 1.003–3.26). AKI was associated with a length of stay ≥3 days when compared with those who did not have AKI (OD 2.98; 95% CI 1.66–5.34). Eight patients (11.3%) with AKI died whereas there were no mortalities in patients without AKI (P < 0.001). Only 5 patients (7%) had persistent kidney dysfunction at discharge.

Conclusions

AKI in DVI is associated with neurological involvement, prolongation of aPTT, greater length of hospital stay and increased mortality.

Approach to the international traveler with neurological symptoms

ABSTRACT 

International travelers commonly contract illnesses while abroad, with the highest risk in those who spend extended time in developing countries. As travel to worldwide destinations becomes more accessible, neurologists should be aware of travel-related infections and noninfectious conditions presenting with neurological manifestations. Travelers may present with a myriad of neurologic symptoms, including confusion, headache, weakness and sensory symptoms. In this review, we discuss the general approach to the returning traveler with neurological symptoms and discuss the differential diagnosis of symptoms commonly encountered in practice.

Distribution of rickettsioses in Oceania: past patterns and implications for the future

Rickettsioses present a threat to human health worldwide, but relatively little is known on their epidemiology and ecology in Oceania. These bacteria are the cause of potentially fatal febrile illnesses in humans (categorized into scrub typhus, typhus group and spotted fever group rickettsioses). They are transmitted by arthropod vectors such as ticks, mites, fleas and lice, which are associated with vertebrate host animals including rodents and companion animals. We conducted a search in the scientific and grey literature of Rickettsia spp. and Orientia tsutsugamushi within the Oceania region. Human case reports, human serosurveys and PCR-based testing of vectors and host animals reviewed here highlight the widespread distribution of these pathogens in the region, with the majority of human serological and vector surveys reporting positive results. These findings suggest that rickettsioses may have a significantly higher burden of disease in Oceania than is currently appreciated due to diagnostic challenges. Furthermore, consideration of the ecology and risk factors for rickettsioses reported for Oceania suggests that their importance as a cause of undifferentiated acute febrile illness may grow in the future: environmental and social changes driven by predicted climate change and population growth have the potential to lead to the emergence of rickettsioses as a significant public health problem in Oceania.

Prevalence of malaria among acute febrile patients clinically suspected of having malaria in the Zeway Health Center, Ethiopia

Malaria diagnosis is a common challenge in developing countries with limited diagnostic services. Common febrile illnesses were assessed in 280 malaria-suspected patients, and each case was subjected to clinical and laboratory examinations for malaria, relapsing fever, typhoid fever, typhus, and brucellosis. Data were entered and analyzed using Epi Info version 3.1 software. Malaria accounted for 17% (CI, 12.6-21.4%) of febrile illnesses. The remaining cases were associated with typhoid fever (18.5%; CI, 13.95-23.05%), typhus (17.8%; CI, 13.32-22.28%), brucellosis (1%; CI, -0.17-2.17%), relapsing fever (2%; CI, 0.36-3.64%), and unknown causes (44%). Approximately 7% of patients had coinfections, and 2% of patients treated as monoinfections. Approximately 1.4% of the nonmalarial patients received antimalarial treatment. The sensitivity and specificity of the CareStart Pf/pan rapid diagnostic tests in comparison with those of microscopy were 100% and 91%, respectively, with positive- and negative-predictive values of 94% and 100%, respectively. Compared with microscopy, the positive-predictive value of each malaria symptom was much lower than that of the symptoms combined: fever, 17%; sweating, 30%; headache, 18%; general body ache, 22%; loss of appetite, 21%. The study findings revealed a high proportion of nonmalarial illnesses were clinically categorized as malaria. Parasite-based diagnosis is recommended for the management of malarial and nonmalarial cases.

Predictors of hospital stay and mortality in dengue virus infection-experience from Aga Khan University Hospital Pakistan

Background

Dengue virus infection (DVI) is very common infection. There is scarcity of data on factor associated with increased hospital stay and mortality in dengue virus infection (DVI). This study was done to know about factors associated with increased hospital stay and mortality in patients admitted with DVI.

Results

Out of 532 patients, two third (72.6%) had stay ≤3 days while one third (27.4%) had stay greater than 3 days. The mean length of hospital stay was 3.46 ± 3.45 days. Factors associated with increased hospital stay (>3 days) included AKI (acute kidney injury) (Odd ratio 2.98; 95% CI 1.66-5.34), prolonged prothrombin time (Odd ratio 2.03; 95% CI 1.07-3.84), prolonged activated partial thromboplastin time (aPTT) (Odd ratio 1.80; CI 95% 1.15-2.83) and increased age of > 41.10 years (Odd ratio 1.03; CI 95% 1.01-1.04).Mortality was 1.5%. High mortality was found in those with AKI (P <0.01), dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS) (P <0.001), respiratory failure (P0.01), prolong PT (P 0.001), prolong aPTT (P0.01) and increased hospital stay (P0.04).

Conclusion

Increasing age, coagulopathy and acute kidney injury in patients with DVI is associated with increased hospital stay. Morality was more in patients with AKI, DHF and DSS, respiratory failure, coagulopathy and these patients had more prolonged hospitalization.

Rickettsial infections in Southeast Asia: implications for local populace and febrile returned travelers

Rickettsial infections represent a major cause of non-malarial febrile illnesses among the residents of Southeast Asia and returned travelers from that region. There are several challenges in recognition, diagnosis, and management of rickettsioses endemic to Southeast Asia. This review focuses on the prevalent rickettsial infections, namely, murine typhus (Rickettsia typhi), scrub typhus (Orientia tsutsugamushi), and members of spotted fever group rickettsiae. Information on epidemiology and regional variance in the prevalence of rickettsial infections is analyzed. Clinical characteristics of main groups of rickettsioses, unusual presentations, and common pitfalls in diagnosis are further discussed. In particular, relevant epidemiologic and clinical aspects on emerging spotted fever group rickettsiae in the region, such as Rickettsia honei, R. felis, R. japonica, and R. helvetica, are presented. Furthermore, challenges in laboratory diagnosis and management aspects of rickettsial infections unique to Southeast Asia are discussed, and data on emerging resistance to antimicrobial drugs and treatment/prevention options are also reviewed.

Feasibility and clinical outcomes when using practice guidelines for evaluation of fever in returning travelers and migrants: a validation study

BACKGROUND

Practice guidelines for examining febrile patients presenting upon returning from the tropics were developed to assist primary care physicians in decision making. Because of the low level of evidence available in this field, there was a need to validate them and assess their feasibility in the context they have been designed for.

OBJECTIVES

The objectives of the study were to (1) evaluate physicians' adherence to recommendations; (2) investigate reasons for non-adherence; and (3) ensure good clinical outcome of patients, the ultimate goal being to improve the quality of the guidelines, in particular to tailor them for the needs of the target audience and population.

METHODS

Physicians consulting the guidelines on the Internet (www.fevertravel.ch) were invited to participate in the study. Navigation through the decision chart was automatically recorded, including diagnostic tests performed, initial and final diagnoses, and clinical outcomes. The reasons for non-adherence were investigated and qualitative feedback was collected.

RESULTS

A total of 539 physician/patient pairs were included in this study. Full adherence to guidelines was observed in 29% of the cases. Figure-specific adherence rate was 54.8%. The main reasons for non-adherence were as follows: no repetition of malaria tests (111/352) and no presumptive antibiotic treatment for febrile diarrhea (64/153) or abdominal pain without leukocytosis (46/101). Overall, 20% of diversions from guidelines were considered reasonable because there was an alternative presumptive diagnosis or the symptoms were mild, which means that the corrected adherence rate per case was 40.6% and corrected adherence per figure was 61.7%. No death was recorded and all complications could be attributed to the underlying illness rather than to adherence to guidelines.

CONCLUSIONS

These guidelines proved to be feasible, useful, and leading to good clinical outcomes. Almost one third of physicians strictly adhered to the guidelines. Other physicians used the guidelines not to forget specific diagnoses but finally diverged from the proposed attitudes. These diversions should be scrutinized for further refinement of the guidelines to better fit to physician and patient needs.

Assessment of returning travellers with fever

Millions of people travel to the tropics each year and a significant minority of them become ill, either during their stay, or shortly after their return. Most have mild, self-limiting illnesses, but a few will have a life-threatening condition. This article outlines how to evaluate fever in the returning traveller and discusses important infection control and public health measures. A detailed travel history, which takes into account travel destinations, specific activities and risk factors in relation to the onset of symptoms, is essential for constructing a comprehensive list of differential diagnoses and guiding appropriate investigations. Importantly, all travellers returning from the tropics with a fever should be investigated for malaria, even if their return was 3 months ago or longer.

Central nervous system infections in travelers

International travelers commonly contract infections while abroad, many of which are primary neurological diseases or have potential neurological sequelae. The implications of these neuroinfectious diseases extend beyond the individual, since returning travelers may contribute to the spread of infection in novel areas. In this review, we discuss signs, symptoms, treatments, and prophylaxes for these infections, as well as emerging trends with regard to neuroinfectious diseases of the returning traveler.

Dengue fever and international travel

BACKGROUND

Dengue is a leading public health problem with an expanding global burden. Dengue virus is also a significant cause of illness in international travelers with an increasing number of cases of dengue fever identified in travelers returning from dengue-endemic countries.

METHODS

This review focuses on the clinical illness of dengue infection in international travelers and provides a summary of the risk of infection for travelers, clinical features of infection, and an overview of dengue vaccines and their potential applicability to travelers.

RESULTS

Four prospective studies of travelers to dengue-endemic destinations have shown that the dengue infection incidence ranges from 10.2 to 30 per 1,000 person-months. This varies according to travel destination and duration and season of travel. Dengue is also a common cause of fever in returned travelers, accounting for up to 16% of all febrile illnesses in returned travelers. Although the majority of infections are asymptomatic, a small proportion of travelers develop dengue hemorrhagic fever. The diagnosis of dengue in travelers requires a combination of serological testing for IgG and IgM together with either nucleic acid or NS1 antigen testing. Several vaccine candidates have now entered into clinical trials including ChimeriVax Dengue, which is currently in phase 3 trials, live-attenuated chimeric vaccines (DENV-DENV Chimera, Inviragen), live-attenuated viral vaccines, recombinant protein subunit vaccines, and DNA vaccines.

CONCLUSIONS

Dengue infection in international travelers is not infrequent and may be associated with substantial morbidity. Furthermore, an accurate diagnosis of dengue in travelers requires the use of a combination of diagnostic tests. Although a vaccine is not yet available a number of promising candidates are under clinical evaluation. For now travelers should be provided with accurate advice regarding preventive measures when visiting dengue-endemic areas.

Cases of typhoid fever in Copenhagen region: a retrospective study of presentation and relapse

Background

Typhoid fever is a systemic illness which in high-income countries mainly affects travellers. The incidence is particularly high on the Indian subcontinent. Travellers who visit friends and relatives (VFR) have been shown to have a different risk profile than others. We wished to identify main characteristics for travellers infected with S. Typhi considering both clinical and laboratory findings in order to provide for faster and better diagnostics in the future. The outcome of treatment, especially concerning relapse, was evaluated as well.

Methods

Retrospectively collected data from 19 adult cases of typhoid fever over a 5-year period at the Department of Infectious Diseases, Copenhagen University Hospital, Hvidovre Denmark.

Results

The patients were young adults, presenting with symptoms within a month after travelling. 84% were returned from travelling in the Indian subcontinent. 17 out of 19 patients were VFR-travellers. The main symptoms were fever (100%), gastrointestinal symptoms (84%), headache (58%) and dry cough (26%). Laboratory findings showed elevated C-reactive protein (CRP) and lactate dehydrogenase (LDH) in all cases and elevated alanine transaminase (ALAT) in 47% of cases. In primary cases 4 isolates were fully susceptible to ciprofloxacin, the remaining were intermediate susceptible. Relapse occurred in 37% of the cases and only in cases where the patient was infected by a strain with intermediate susceptibility.

Conclusions

Better pre-travel counselling should be given to VFR-travellers. The main symptoms and laboratory findings confirm previous findings. The relapse rate was unexpected high and could be correlated to ciprofloxacin-resistance.

Fever in the tropics: aetiology and case-fatality - a prospective observational study in a tertiary care hospital in South India

BACKGROUND

The objective of this study was to describe aetiology and case fatality of fever among inpatients in a tertiary care hospital in South India.

METHODS

This was an observational, prospective study conducted in a tertiary care hospital in Vellore, Tamil Nadu, India. Between July 2nd 2007 and August 2nd in 2007, adult patients admitted to the hospital with temperature ≥ 38.0°C were included consecutively and followed during the hospitalisation period. Demographic and clinical data were collected and analysed for each patient. Associations were sought between death and various clinical and demographic variables.

RESULTS

One hundred patients were included, 61 male and 39 female. Mean age was 37.5 (range: 16 to 84) years. Mean fever duration was 5.4 (range: 0.1 to 42.9) weeks.The following infectious aetiologies were recorded: tuberculosis (19%), lower respiratory infection (11%) including three with sepsis, urinary tract infection (10%) including three with E. coli sepsis, Plasmodium falciparum malaria (5%) including three patients with mixed P. vivax infection, scrub typhus (5%), typhoid fever (4%), cryptococcal meningitis (4%) including three HIV positive patients, endocarditis (3%) including two patients with Staphylococcus aureus sepsis, spleen abscess (2%), amoebic liver abscess (2%), sepsis undefined focus (1%), HIV infection (1%), hepatitis B (1%), rubella (1%), peritonitis (1%) and cholecystitis (1%).Non-infectious causes of fever were diagnosed in 15%, including systemic lupus erythematosus in four and malignancy in six patients. Cause of fever remained unknown in 13%.Case fatality during hospitalisation was 7% (7/100). Six of those who died were male. Five fatalities had bacterial sepsis, one spleen abscess and malignancy, and one had lymphomalignant disorder.Diabetes and increasing age were significant risk factors for fatal outcome in unadjusted analyses, but only increasing age was a risk factor for death in adjusted analysis.

CONCLUSIONS

A high number of tuberculosis and bacterial infections and a high case fatality rate from sepsis were found in this cohort, underlining the importance of microbiological diagnostics and targeted antimicrobial treatment in the management of fever. P. falciparum was identified in all malaria cases, and this rapidly fatal infection should be considered in patients with acute undifferentiated fever in India.

Coughing and fever after surfing in Central America

We report the case of a 19-year-old surfer, returning from Central America, who presented with chronic cough. The X-ray and full blood count, which had been performed in Costa Rica, were without pathology; laboratory parameters showed slightly increased C-reactive protein (59 mg/l). Malaria was excluded by thick smear. Immune serological tests for typhus, paratyphus, brucellosis, rickettsioses, leptospirosis and dengue fever were negative. An ambulant antimicrobial treatment was without any clinical effect. A computer tomography of the thorax showed a solid lesion (30 × 20 mm, middle lobe of the right lung). The patient rejected a bronchoscopic examination. He decided to be treated after his return to Austria. Here, we could substantiate a pulmonal histoplasmosis by a positive immune diffusion test. The patient was successfully treated with itraconazole.

Parasitic liver disease in travelers

Liver disease is an important source of morbidity among ill returning travelers. Jaundice is one of the most common and obvious symptoms of liver disease, the differential diagnosis of which is extensive, especially in travelers. Jaundice in travelers can arise from both infectious and noninfectious causes. We herein summarize the most common parasitic etiologies that may lead to jaundice in the returned traveler, visitors of friends and relatives, or new immigrants, and describe the etiology, epidemiology, and pathogenesis of clinical features of each.

Dengue in travellers: applicability of the 1975-1997 and the 2009 WHO classification system of dengue fever

OBJECTIVES

The aim of this study was to assess the applicability and benefits of the new WHO dengue fever guidelines in clinical practice, for returning travellers.

METHODS

We compared differences in specificity and sensitivity between the old and the new guidelines for diagnosing dengue and assessed the usefulness in predicting the clinical course of the disease. Also, we investigated whether hypertension, diabetes or allergies, ethnicity or high age influenced the course of disease.

RESULTS

In our setting, the old classification, compared with the new, had a marginally higher sensitivity for diagnosing dengue. The new classification had a slightly higher specificity and was less rigid. Patients with dengue who had warning signs as postulated in the new classification were admitted more often than those who had no warning signs (RR, 8.09 [1.80-35.48]). We did not find ethnicity, age, hypertension, diabetes mellitus or allergies to be predictive of the clinical course.

CONCLUSIONS

In our cohort of returned travellers, the new classification system did not differ in sensitivity and specificity from the old system to a clinically relevant degree. The guidelines did not improve identification of severe disease.