The exanthem of dengue fever: Clinical features of two US tourists traveling abroad

Increasing the Awareness of Under-Diagnosed Tropical Cases of Dengue in Romania

Global travelling increases every year and according to a report released during the COVID-19 pandemic by the UN World Tourism Organization, international travel doubled in 2022, compared to levels in 2021. his fact led also to travel-imported cases of arboviral infections and physicians are often confronted with tropical diseases, such as dengue or chikungunya. Since there is are no pathognomonic cues for these tropical illnesses, early diagnosis is still a big challenge and it depends on many factors, such as exposure risk factors, the epidemiological context, the incubation period, and the wide spectrum of differential diagnoses, including cosmopolitan or exotic infections. Since the clinical presentation of dengue is not typical and there are other febrile illnesses similar to arboviral diseases, misdiagnosis is common even among experienced doctors. Differential diagnosis needs up to date knowledge considering the short viraemic period, the antibody cross-reactivity, and the traps in recognising the nonspecific symptom picture. We present two cases of Dengue diagnosed in Romania which were initially clinically misconstrued, despite the characteristic symptom picture. The main purpose is to increase the level of awareness and to underline the difficulties that clinicians face in recognizing travel-related imported dengue virus disease.

Cutaneous manifestations of viral outbreaks

As the world tries to grapple with the COVID-19 pandemic, dermatologists are left in a lurch as there is a lacuna in dermatologic literature as well as training regarding the cutaneous manifestations of varied viral agents capable of causing epidemics/pandemics or the potential to be bio-weaponised. Such outbreaks have the potential to become a pandemic given this age of globalisation. The quote by George Santayana stands true 'Those who cannot remember the past are condemned to repeat it'. Thus, this article lends a perspective to the recent viral outbreaks and is aimed at summarising these agents and their clinical features to serve as a quick reference for dermatologists.

Morbilliform skin rash with prominent involvement of the palms in Chikungunya fever

An outbreak of chikungunya occurred in Central Italy in the summer of 2017. During the outbreak, two siblings with fever and joint pain developed a morbilliform skin rash with prominent involvement of the palms. Knowledge of the characteristics of chikungunya exanthem is important to adddress clinical diagnosis.

Detection of selected arboviral infections in patients with history of persistent fever in Pakistan

Surveillance is a valuable tool for understanding prevailing and previously undiagnosed infections in a geographic area. We examined 480 archived serum samples from patients with history of persistent fever (>40°C, 60-72h) who were referred to hospitals in Rawalpindi/Islamabad, Lahore, and Faisalabad districts for dengue antibody detection in 2014-15. Each sample was processed for detection of antigens and seroconversion, using real-time polymerase chain reaction and enzyme linked immunosorbent assay, respectively, against dengue haemorrhagic fever (DHF) virus serotypes 1-4, West Nile virus fever (WNVF), Crimean-Congo haemorrhagic fever (CCHF), and Chikungunya virus (CGV). The presence of antigens and antibodies to at least one of the studied viral haemorrhagic fevers (VHFs) was detected in 465 (96.8%, 95% CI: 94.9-98.1) and 442 samples (92.1%, 95% CI: 89.3-94.2), respectively. No sera were found positive to CCHF. There was a significant association between gender and positivity to at least one of the VHFs (χ²=8.12, df=1, p<0.005). Except for DHF serotype 2 and 3 (ττ=0.41), Goodman and Kruskal's Tau statistic revealed no significant association for occurrence of different viruses within the studied population (ττ=0-0.06). Cosinor analysis confirmed significant seasonality, with a higher number of cases of persistent fever in August through November, peaking in October. The study suggests circulation of multiple arthropod-borne viral infections and, in addition to DHF, ascertain the needs for screening patients for CGV and WNVF too. It also demonstrates the necessity of well-integrated disease surveillance in several geographic regions and at-risk populations in Pakistan to develop appropriate disease and vector control strategies.

Seroprevalence of Infections with Dengue, Rift Valley Fever and Chikungunya Viruses in Kenya, 2007

Arthropod-borne viruses are a major constituent of emerging infectious diseases worldwide, but limited data are available on the prevalence, distribution, and risk factors for transmission in Kenya and East Africa. In this study, we used 1,091 HIV-negative blood specimens from the 2007 Kenya AIDS Indicator Survey (KAIS 2007) to test for the presence of IgG antibodies to dengue virus (DENV), chikungunya virus (CHIKV) and Rift Valley fever virus (RVFV).The KAIS 2007 was a national population-based survey conducted by the Government of Kenya to provide comprehensive information needed to address the HIV/AIDS epidemic. Antibody testing for arboviruses was performed on stored blood specimens from KAIS 2007 through a two-step sandwich IgG ELISA using either commercially available kits or CDC-developed assays. Out of the 1,091 samples tested, 210 (19.2%) were positive for IgG antibodies against at least one of the three arboviruses. DENV was the most common of the three viruses tested (12.5% positive), followed by RVFV and CHIKV (4.5% and 0.97%, respectively). For DENV and RVFV, the participant’s province of residence was significantly associated (P≤.01) with seropositivity. Seroprevalence of DENV and RVFV increased with age, while there was no correlation between province of residence/age and seropositivity for CHIKV. Females had twelve times higher odds of exposure to CHIK as opposed to DENV and RVFV where both males and females had the same odds of exposure. Lack of education was significantly associated with a higher odds of previous infection with either DENV or RVFV (p <0.01). These data show that a number of people are at risk of arbovirus infections depending on their geographic location in Kenya and transmission of these pathogens is greater than previously appreciated. This poses a public health risk, especially for DENV.

[Exanthems and fever in travellers returning from the tropics]

Dengue fever with its subtle rash is today more common than malaria in travellers returning to Europe from the tropics (meta-analysis Geo Sentinel network). Up to 5 % of all safari tourists experience African tick bite fever during or soon after their journey; it is caused by rickettsiae and clinically presents with exanthems, focal necrotizing vasculitis (eschar, tache noir), lymphadenopathy and moderate fever. Typhoid fever is a severe infectious disease is which is difficult to diagnosis at first assessment. The presence of rose spots, which may be found in up to 33 % of patients with typhoid fever, can lead the way to diagnosis. Exanthems can be subtle and may occur weeks after infection without any other distinctive clinical sign. Particular importance in travel medicine has to be paid to acute HIV infection and secondary syphilis after exposition and infection in the tropics. Also the highly contagious infectious diseases of childhood as measles and rubeola have to be taken into account in adults with no or insufficient vaccination after a stay in tropical countries.

Serologic evidence of arboviral infections among humans in Kenya

Outbreaks of arthropod-borne viral infections occur periodically across Kenya. However, limited surveillance takes place during interepidemic periods. Using serum samples obtained from asymptomatic persons across Kenya in 2000-2004, we assessed (by indirect immunofluorescent assay) prevalence of IgG against yellow fever virus (YFV), West Nile virus (WNV), tick-borne encephalitis virus (TBEV), dengue virus serotypes 1-4 (DENV1-4), and chikungunya virus (CHIKV). Older persons on the Indian Ocean coast were more likely to be seropositive than children inland: YFV = 42% versus 6%, WNV = 29% versus 6%, TBEV = 16% versus 6%, DENV-1 = 63% versus 9%, DENV-2 = 67% versus 7%, DENV-3 = 55% versus 6%, DENV-4 = 44% versus 8%, and CHIKV = 37% versus 20%. Among inland samples, children in lowlands were more likely to be seropositive for CHIKV (42% versus 0%) than children in highlands. In Kenya, transmission of arboviral infection continues between known epidemics and remains common across the country.

A retrospective cohort study of dermatological problems observed in paediatric intensive care unit

BACKGROUND

Dermatological manifestations are often encountered in paediatric intensive care units (PICU). Spectrum of dermatological problems that may arise in critically ill children in intensive care unit remains unknown.

OBJECTIVES

The aim of this study was to find out the burden of dermatological problems and to describe the proportional distribution of paediatric dermatoses in ICU set-up.

METHODS

In a retrospective cohort study, we analysed all types of paediatric dermatological conditions manifesting in children admitted to a tertiary level ICU in South India.

RESULTS

During the study period of 25 months, 1180 new cases were admitted to PICU. A total of 318 children with 361 skin manifestations were observed. Majority of the skin lesions were minor and were secondary to systemic disease. Infection was the leading cause of dermatoses in ICU. Dengue infection was detected in 64% of total cases included in the study. Stevens-Johnson syndrome was the only primary dermatological condition leading to PICU admission in the present cohort.

CONCLUSIONS

The spectrum and proportional distribution of skin conditions in children differ from adult ICU-data. Further large-scale investigations are needed to define the characteristics and distribution of infections along with other disease conditions leading to ICU-admissions and mortality among critically ill paediatric patients.

Skin disorders among travellers returning from tropical and non-tropical countries consulting a travel medicine clinic

OBJECTIVE

To evaluate the causes and risks for imported skin disorders among travellers.

METHODS

Data of 34,162 travellers returning from tropical and non-tropical countries and presenting at the outpatient travel medicine clinic of the University of Munich, Germany, between 1999 and 2009 were analyzed for this study. Of these, 12.2% were diagnosed with skin disorders.

RESULTS

Main destinations visited were Asia (40%), Africa (27%) and Latin America (21%). Tourism in the form of adventure travel/backpacking (47%) and package holidays (23%) was the most common purpose of travel. The leading causes of skin disorders were arthropodal (23%), bacterial (22%), helminthic (11%), protozoan (6%), viral (6%), allergic (5%) and fungal (4%). The 10 most frequently diagnosed specific skin diseases associated with specific destinations were insect bites (17%, Southern Europe), cutaneous larva migrans (8%, Asia and Latin America), cutaneous leishmaniasis (2.4%, Mediterranean Region/Middle East), dengue fever (1.5%, Asia), rickettsioses (1.3%, Southern Africa), myiasis (0.8%, Central America), filarioses (0.7%, Africa), tick bites (0.6%, Central/Eastern Europe), schistosomiasis (0.6%, Africa) and tungiasis (0.6%, Africa). Travellers in sub-Saharan Africa had the highest relative risk of acquiring skin disorders.

CONCLUSION

As more than 20% of all skin disorders among returned travellers were caused by arthropods and about 50% by infectious pathogens, pre-travel consultations should include specific prophylaxis and consider the most important risk factor for the travel destination.

Mucocutaneous manifestations of Dengue fever

Dengue viral infection is a cause of considerable morbidity and mortality and may be associated with a variety of mucocutaneous manifestations that may provide important early clues to the diagnosis of this condition. Cutaneous and mucosal findings like confluent erythema, morbilliform eruptions, and hemorrhagic lesions may figure prominently in the clinical features of dengue. The differential diagnoses include a large number of bacterial and viral exanthems as well as drug rash.

Dengue virus-induced hemorrhage in a nonhuman primate model

Lack of a dengue hemorrhagic animal model recapitulating human dengue virus infection has been a significant impediment in advancing our understanding of the early events involved in the pathogenesis of dengue disease. In efforts to address this issue, a group of rhesus macaques were intravenously infected with dengue virus serotype 2 (strain 16 681) at 1 x 10(7) PFU/animal. A classic dengue hemorrhage developed 3 to 5 days after infection in 6 of 6 animals. Blood chemistry appeared to be normal with exception of creatine phosphokinase, which peaked at 7 days after infection. A modest thrombocytopenia and noticeable neutropenia concomitant with slight decrease of hemoglobin and hematocrit were registered. In addition, the concentration of D-dimer was elevated significantly. Viremia peaked at 3 to 5 days after infection followed by an inverse relationship between T and B lymphocytes and a bimodal pattern for platelet-monocytes and platelet-neutrophil aggregates. Dengue virus containing platelets engulfed by monocytes was noted at 8 or 9 days after infection. Thus, rhesus macaques inoculated intravenously with a high dose of dengue virus produced dengue hemorrhage, which may provide a unique platform to define the early events in dengue virus infection and help identify which blood components contribute to the pathogenesis of dengue disease.