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Molecular Characterisation of Chikungunya Virus Infections in Trinidad and Comparison of Clinical and Laboratory Features with Dengue and Other Acute Febrile Cases  [PDF]
Nikita Sahadeo?,Hamish Mohammed?,Orchid M. Allicock?,Albert J. Auguste?,Steven G. Widen?,Kimberly Badal?,Krishna Pulchan?,Jerome E. Foster?,Scott C. Weaver?,Christine V. F. Carrington
PLOS Neglected Tropical Diseases , 2015, DOI: 10.1371/journal.pntd.0004199
Abstract: Local transmission of Chikungunya virus (CHIKV) was first documented in Trinidad and Tobago (T&T) in July 2014 preceding a large epidemic. At initial presentation, it is difficult to distinguish chikungunya fever (CHIKF) from other acute undifferentiated febrile illnesses (AUFIs), including life-threatening dengue disease. We characterised and compared dengue virus (DENV) and CHIKV infections in 158 patients presenting with suspected dengue fever (DF) and CHIKF at a major hospital in T&T, and performed phylogenetic analyses on CHIKV genomic sequences recovered from 8 individuals. The characteristics of patients with and without PCR-confirmed CHIKV were compared using Pearson’s χ2 and student’s t-tests, and adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were determined using logistic regression. We then compared signs and symptoms of people with RT-qPCR-confirmed CHIKV and DENV infections using the Mann-Whitney U, Pearson’s χ2 and Fisher’s exact tests. Among the 158 persons there were 8 (6%) RT-qPCR-confirmed DENV and 30 (22%) RT-qPCR-confirmed CHIKV infections. Phylogenetic analyses showed that the CHIKV strains belonged to the Asian genotype and were most closely related to a British Virgin Islands strain isolated at the beginning of the 2013/14 outbreak in the Americas. Compared to persons who were RT-qPCR-negative for CHIKV, RT-qPCR-positive individuals were significantly more likely to have joint pain (aOR: 4.52 [95% CI: 1.28–16.00]), less likely to be interviewed at a later stage of illness (days post onset of fever—aOR: 0.56 [0.40–0.78]) and had a lower white blood cell count (aOR: 0.83 [0.71–0.96]). Among the 38 patients with RT-qPCR-confirmed CHIKV or DENV, there were no significant differences in symptomatic presentation. However when individuals with serological evidence of recent DENV or CHIKV infection were included in the analyses, there were key differences in clinical presentation between CHIKF and other AUFIs including DF, which can be used to triage patients for appropriate care in the clinical setting.
Clinical Behavior of Dengue and Chikungunya Infections in the Instituto Mexicano del Seguro Social  [PDF]
Joel Navarrete-Espinosa, Joaquín Gonzalez-Ibarra, Clara E. Santa Cruz-Tinoco, Cesar R. Gonzalez-Bonilla, Miguel Pacheco-Hernández, José E. Mu?oz-Medina
Open Journal of Medical Microbiology (OJMM) , 2016, DOI: 10.4236/ojmm.2016.61005
Abstract: Arbovirus infections have increased worldwide in the last years and specific differential diagnosis may be difficult owing to their similar clinical presentations. Here we describe and compare the clinical manifestations of dengue and chikungunya fever. Material and Methods: In order to portray the clinical behavior of both diseases, a cross-sectional study was performed including patients insured by the Mexican Institute for Social Security (IMSS), their demographic data, and clinical signs and symptoms. Laboratory parameters were analyzed. Results: One thousand four hundred and ninety-five dengue and 1810 chikungunya cases were studied. All patients presented fever, whereas headache, myalgias, mild arthralgias, and ocular pain were more frequent in dengue cases. Severe incapacitating polyarthralgias, arthritis, and conjunctivitis were present only in chikungunya cases. Also, edema and exanthema were more frequent in patients with chikungunya. Liquid leak to tissues and hemorrhage were more frequent among dengue cases. Platelet counts were lower in hemorrhagic dengue (P < 0.001). Laboratory parameters were altered between the second and third day of evolution and tended to return to normal from the fifth day. Discussion: The clinical features observed in this group of patients may contribute to the differential diagnosis of both diseases. The cardinal signs of severity were not present in all cases of any of the two diseases. It is important to consider these issues in order to establish an early diagnosis and improve the prognosis of patients.
Soedarto Soekiman
Bulletin of Health Research , 2012,
Abstract: Colonies of Aedes aegypti (Surabaya strain) and Aedes albopictus (Malang strain) were studied to compare their susceptibility to oral infection with dengue type 3 and Chikungunya viruses. Growth curves of dengue type 3 and Chikungunya viruses in these mosquitoes indicated that both mosquito species were susceptible to oral infection with these viruses. Electron microscopic observation of the salivary glands of A. aegypti and A. albopictus infected with Chikungunya virus showed that this organ plays an important role in producing and maintaining high virus titers in these mosquitoes. The results suggest that both Aedes species are potentially important vectors on the transmission of dengue and Chikungunya infection in Indonesia.
The Hidden Burden of Dengue and Chikungunya in Chennai, India  [PDF]
Isabel Rodríguez-Barraquer?,Sunil S. Solomon?,Periaswamy Kuganantham?,Aylur Kailasom Srikrishnan?,Canjeevaram K. Vasudevan?,Syed H. Iqbal?,Pachamuthu Balakrishnan?,Suniti Solomon?,Shruti H. Mehta?,Derek A. T. Cummings
PLOS Neglected Tropical Diseases , 2015, DOI: 10.1371/journal.pntd.0003906
Abstract: Background Dengue and chikungunya are rapidly expanding viruses transmitted by mosquitoes of the genus Aedes. Few epidemiological studies have examined the extent of transmission of these infections in South India despite an increase in the number of reported cases, and a high suitability for transmission. Methods and findings We conducted a household-based seroprevalence survey among 1010 individuals aged 5-40 years living in fifty randomly selected spatial locations in Chennai, Tamil Nadu. Participants were asked to provide a venous blood sample and to complete a brief questionnaire with basic demographic and daily activity information. Previous exposure to dengue and chikungunya was determined using IgG indirect ELISA (Panbio) and IgG ELISA (Novatec), respectively. We used this data to estimate key transmission parameters (force of infection and basic reproductive number) and to explore factors associated with seropositivity. While only 1% of participants reported history of dengue and 20% of chikungunya, we found that 93% (95%CI 89-95%) of participants were seropositive to dengue virus, and 44% (95%CI 37-50%) to chikungunya. Age-specific seroprevalence was consistent with long-tem, endemic circulation of dengue and suggestive of epidemic chikungunya transmission. Seropositivity to dengue and chikungunya were significantly correlated, even after adjusting for individual and household factors. We estimate that 23% of the susceptible population gets infected by dengue each year, corresponding to approximately 228,000 infections. This transmission intensity is significantly higher than that estimated in known hyperendemic settings in Southeast Asia and the Americas. Conclusions These results provide unprecedented insight into the very high transmission potential of dengue and chikungunya in Chennai and underscore the need for enhanced surveillance and control methods.
Evidence for Endemic Chikungunya Virus Infections in Bandung, Indonesia  [PDF]
Herman Kosasih,Quirijn de Mast,Susana Widjaja,Primal Sudjana,Ungke Antonjaya,Chairin Ma'roef,Silvita Fitri Riswari,Kevin R. Porter,Timothy H. Burgess,Bachti Alisjahbana ,Andre van der Ven,Maya Williams
PLOS Neglected Tropical Diseases , 2013, DOI: 10.1371/journal.pntd.0002483
Abstract: Chikungunya virus (CHIKV) is known to cause sporadic or explosive outbreaks. However, little is known about the endemic transmission of CHIKV. To ascertain the endemic occurrence of CHIKV transmission, we tested blood samples from patients with a non-dengue febrile illness who participated in a prospective cohort study of factory workers in Bandung, Indonesia. From August 2000 to June 2004, and September 2006 to April 2008, 1901 febrile episodes occurred and 231 (12.2%) dengue cases were identified. The remaining febrile cases were evaluated for possible CHIKV infection by measuring anti-CHIKV IgM and IgG antibodies in acute and convalescent samples. Acute samples of serologically positive cases were subsequently tested for the presence of CHIKV RNA by RT-PCR and/or virus isolation. A total of 135 (7.1%) CHIKV infections were identified, providing an incidence rate of 10.1/1,000 person years. CHIKV infections were identified all year round and tended to increase during the rainy season (January to March). Severe illness was not found and severe arthralgia was not a prominently reported symptom. Serial post-illness samples from nine cases were tested to obtain a kinetic picture of IgM and IgG anti-CHIKV antibodies. Anti-CHIKV IgM antibodies were persistently detected in high titers for approximately one year. Three patients demonstrated evidence of possible sequential CHIKV infections. The high incidence rate and continuous chikungunya cases in this adult cohort suggests that CHIKV is endemically transmitted in Bandung. Further characterization of the circulating strains and surveillance in larger areas are needed to better understand CHIKV epidemiology in Indonesia.
A Re-Examination of the History of Etiologic Confusion between Dengue and Chikungunya  [PDF]
Goro Kuno
PLOS Neglected Tropical Diseases , 2015, DOI: 10.1371/journal.pntd.0004101
Abstract: Contrary to the perception of many researchers that the recent invasion of chikungunya (CHIK) in the Western Hemisphere marked the first episode in history, a recent publication reminded them that CHIK had prevailed in the West Indies and southern regions of the United States from 1827–1828 under the guise of “dengue” (DEN), and that many old outbreaks of so-called “dengue” actually represented the CHIK cases erroneously identified as “dengue.” In hindsight, this confusion was unavoidable, given that the syndromes of the two diseases—transmitted by the same mosquito vector in urban areas—are very similar, and that specific laboratory-based diagnostic techniques for these diseases did not exist prior to 1940. While past reviewers reclassified problematic “dengue” outbreaks as CHIK, primarily based on manifestation of arthralgia as a marker of CHIK, they neither identified the root cause of the alleged misdiagnosis nor did they elaborate on the negative consequences derived from it. This article presents a reconstructed history of the genesis of the clinical definition of dengue by emphasizing problems with the definition, subsequent confusion with CHIK, and the ways in which physicians dealt with the variation in dengue-like (“dengue”) syndromes. Then, the article identifies in those records several factors complicating reclassification, based on current practice and standards. These factors include terms used for characterizing joint problems, style of documenting outbreak data, frequency of manifestation of arthralgia, possible involvement of more than one agent, and occurrence of the principal vector. The analysis of those factors reveals that while some of the old “dengue” outbreaks, including the 1827–1828 outbreaks in the Americas, are compatible with CHIK, similar reclassification of other “dengue” outbreaks to CHIK is difficult because of a combination of the absence of pathognomonic syndrome in these diseases and conflicting background information.
Dengue and chikungunya fever: Resurgent viral infections with prominent mucocutaneous features  [cached]
Bandyopadhyay Debabrata
Indian Journal of Dermatology , 2010,
Dengue viral infections  [cached]
Gurugama Padmalal,Garg Pankaj,Perera Jennifer,Wijewickrama Ananda
Indian Journal of Dermatology , 2010,
Abstract: Dengue viral infections are one of the most important mosquito-borne diseases in the world. Presently dengue is endemic in 112 countries in the world. It has been estimated that almost 100 million cases of dengue fever and half a million cases of dengue hemorrhagic fever (DHF) occur worldwide. An increasing proportion of DHF is in children less than 15 years of age, especially in South East and South Asia. The unique structure of the dengue virus and the pathophysiologic responses of the host, different serotypes, and favorable conditions for vector breeding have led to the virulence and spread of the infections. The manifestations of dengue infections are protean from being asymptomatic to undifferentiated fever, severe dengue infections, and unusual complications. Early recognition and prompt initiation of appropriate supportive treatment are often delayed resulting in unnecessarily high morbidity and mortality. Attempts are underway for the development of a vaccine for preventing the burden of this neglected disease. This review outlines the epidemiology, clinical features, pathophysiologic mechanisms, management, and control of dengue infections.
Differential Protein Modulation in Midguts of Aedes aegypti Infected with Chikungunya and Dengue 2 Viruses  [PDF]
Stéphane Tchankouo-Nguetcheu,Huot Khun,Laurence Pincet,Pascal Roux,Muriel Bahut,Michel Huerre,Catherine Guette,Valérie Choumet
PLOS ONE , 2012, DOI: 10.1371/journal.pone.0013149
Abstract: Arthropod borne virus infections cause several emerging and resurgent infectious diseases. Among the diseases caused by arboviruses, dengue and chikungunya are responsible for a high rate of severe human diseases worldwide. The midgut of mosquitoes is the first barrier for pathogen transmission and is a target organ where arboviruses must replicate prior to infecting other organs. A proteomic approach was undertaken to characterize the key virus/vector interactions and host protein modifications that happen in the midgut for viral transmission to eventually take place.
No clinical or biological difference between Chikungunya and Dengue Fever during the 2010 Gabonese outbreak  [cached]
Dieudonne Nkoghe,Roland Fabrice Kassa Kassa,Ulrich Bisvigou,Mélanie Caron
Infectious Disease Reports , 2012, DOI: 10.4081/idr.2012.e5
Abstract: Chikungunya (CHIKV) and Dengue (DENV) viruses, both arboviruses, have caused multiple outbreaks worldwide. Their clinical features are poorly described in Africa and there is no comparative study, although Chikungunya is considered as a dengue-like disease. We conducted a comparative study of clinical and biological data from CHIKV and DENV positive patients during the 2010 Gabonese outbreak. Patients consulting with general symptoms and having laboratory confirmation for CHIKV or DENV were included. Clinical and biological data were recorded. Statistical analyses were performed using Epi Info. A P value < 0.05 was considered significant. In all, 270 CHIKV+, 53 DENV+ and 20 co-infected patients were included in the study. Headaches, hemorrhage, leukopenia and lymphopenia were significantly (P respectively 0.01, 0.001, 0.02 and 0.001) more frequent in DENV+ patients than in CHIKV+. There was no additive effect of the two viruses. These clinical and hematological disorders are non specific and cannot assist for the differential diagnosis. These diseases are clinically indistinguishable, and need for laboratory confirmation.
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