Risk of Dengue in Travelers: Implications for Dengue Vaccination.

PURPOSE OF REVIEW: Dengue is found in tropics and subtropics that are considered to be popular travel destinations. We set out to review the burden of dengue on international travelers. RECENT FINDINGS: GeoSentinel, a global network of travel medicine providers, has seen an increasing trend of dengue in returning travelers over the past decades. In Southeast Asia, annual proportionate morbidity increased from 50 dengue cases per 1000 ill-returned travelers in non-epidemic years to an average of 159 cases per 1000 travelers during epidemic years. Dengue is the leading cause of fever in returning travelers, having overtaken malaria for travelers to Southeast Asia. Most dengue seroconversion studies in travelers report an attack rate of around 5% depending on duration of travel and destination. Dengue vaccination would be justified for travelers. The first licensed dengue vaccine CYD-TDV is only recommended in seropositive individuals. This review considers preventive measures including how best to use the first licensed dengue vaccine CYD-TDV

Successful smallpox eradication: what can we learn to control COVID-19?

The public health community needs to learn from history and needs to regain its ability to do shoe-leather public health. If we come together collectively and use the public health tools that we have at hand, we will be successful in containing COVID-19 despite geopolitical tensions, just as we were successful in eradicating smallpox despite the Cold War at the time.</jats:p

Yellow Fever in Travelers

Purpose of Review: This decade has seen a resurgence of yellow fever (YF) that has also affected travelers with a record number of international travelers infected by YF virus including the first documented importation of YF into Asia. Recent Findings: The recent resurgence of YF has been attributed largely to sub-optimal vaccination coverage along with waning population-level immunity. New lessons have been learnt with regard to the clinical management of severe YF as a result of the Brazilian outbreak. With increasing YF cases in travelers, travel medicine providers need to familiarize themselves with the diagnosis and clinical management of severe YF. Prevention remains the mainstay, and all efforts need to be taken that travelers do not circumvent the International Health Regulations. More than 80 years of experience with YF vaccine reinforce the generally acceptable safety profile of YF vaccine but highlight the unique serious adverse events of viscerotropic and neurotropic disease, in particular in first-time vaccinees. Summary: Continued physician and traveler education regarding the risks and benefits of YF vaccination is needed, with an urgent need to better define “significant and unavoidable risk” for improved benefit-risk assessments

The first licensed dengue vaccine: can it be used in travelers?

PURPOSE OF REVIEW: The first dengue vaccine (Dengvaxia) was endorsed by the European Medicine Agency and the US Food and Drug Administration. Given the excess risk of severe dengue in seronegative vaccinees, use is restricted to seropositive individuals. Dengvaxia confers high protection against severe dengue in seropositive vaccinees. RECENT FINDINGS: With increasing global travel, the probability of travelers being seropositive increases. Such seropositive travelers may be at increased risk of severe dengue as a result of a second dengue infection during repeat travel. Nevertheless, the use of Dengvaxia in travelers requires a careful analysis of all the factors. Seropositive travelers only present a minority of all travelers. A validated rapid diagnostic test to screen for dengue serostatus is not yet available. Such a test should be highly specific to avoid inadvertent vaccination of seronegative individuals. The three-dose regimen precludes the use in most travelers who tend to present at travel clinics less than 6 weeks prior to departure. Furthermore, questions about potential sub-optimal immunogenicity in seropositives in nonendemic settings, and the need and timing of boosters remain unanswered. SUMMARY: Although there could potentially be substantial protection against severe dengue in seropositive travelers, Dengvaxia is far from an ideal travel vaccine

Can dengue virus be sexually transmitted?

Can dengue virus be sexually transmitted? A literature review revealed one probable case of female-to-male transmission. Even if dengue PCR can occasionally be found in semen or vaginal secretions, reports on sexual transmission are extremely rare. Sexual transmission of DENV has no public health significance.</jats:p