Evidence Of Chikungunya Virus Infection Research Articles

Acute polyarthritis after astay in the Caribbean

A59-year-old female patient presented with acute polyarthritis after aholiday in the Caribbean. In addition, constitutional symptoms as well as myalgia and arthralgia were reported. Imaging demonstrated synovitis of the wrist and fingers without erosive changes. Immunoserological findings were normal with no evidence of autoimmune disease or vasculitis. Further evaluation revealed serological evidence of chikungunya virus infection.

Molecular and serological evidence of chikungunya virus infection with high case fatality among pediatric population with acute encephalitis syndrome: first report from Eastern Uttar Pradesh, India.

Acute encephalitis syndrome (AES) outbreaks in children of Eastern Uttar Pradesh (E-UP) region of India have been a longstanding public health issue, with a significant case fatality rate of 20-25%. Since past decade, a rise in chikungunya (CHIK) cases has been occurring, which is a reported etiology of AES. However, the burden of chikungunya virus (CHIKV) among pediatric AES (pAES) is unknown from E-UP. We included 238 hospitalized pAES cases. The presence of IgM antibodies for CHIKV, and Dengue virus (DENV) was tested, and RT-PCR was performed for CHIKV and DENV in serologically confirmed CHIKV and DENV pAES cases. Positive samples were sequenced using Sangers sequencing. Further, to check for co-infection, IgM antibodies for other AES etiologies including Japanese encephalitis virus (JEV), Leptospira and Orientia tsutsugamushi (OT) in serum were also investigated. IgM ELISA demonstrated 5.04% (12) positivity for CHIKV. Among CHIKV IgM positive, 3 (25%, 3/12) pAES patients died. CHIKV genome was detected in 3 pAES specimens. Among which, 2 CHIKV cases were also positive for OT DNA. Partially sequenced CHIKV were genotyped as ECSA. The overall finding indicates evidence of CHIKV infection with high case fatality among pAES patients from E-UP. This study advocates constant serological and molecular surveillance of CHIKV in AES endemic regions of India.

Serological and molecular evidence of chikungunya virus infection among febrile outpatients seeking healthcare in Northern Malawi

ABSTRACT Introduction: Despite global evidence of chikungunya fever (CHIKF) in humans that is caused by chikungunya virus (CHIKV), little is known about the occurrence of CHIKF in Malawi. This study was conducted to determine the seroprevalence of CHIKF and to molecularly confirm the presence of CHIKV ribonucleic acid (RNA) among febrile outpatients seeking health care at Mzuzu Central Hospital in the Northern Region of Malawi. Methods: Enzyme-immunosorbent assay (ELISA) was used to detect the presence or absence of specific antibodies against CHIKV. Reverse transcription-polymerase chain reaction (RT-PCR) was conducted on randomly selected anti-CHIKV IgM-positive samples to detect CHIKV RNA. Results: Out of 119 CHIKF suspected samples analyzed, 73 tested positive for anti-CHIKV IgM antibodies, with an overall seroprevalence of 61.3%. Most of the CHIKV infected individuals presented with joint pain, abdominal pain, vomiting and nose bleeding with seroprevalence of 45.2%, 41.1%, 16.4% and 12.3%, respectively. All the randomly selected samples that were positive for CHIKV anti-IgM by ELISA had detectable CHIKV RNA by RT-PCR. Conclusion: The presence of anti-CHIKV IgM antibodies suggests the presence of recent CHIKV infection. We therefore recommend for the inclusion of CHIKF as the differential diagnosis in febrile ill patients in Mzuzu city, Malawi.

Lack of Evidence of Chikungunya Virus Infection among Blood Donors during the Chikungunya Outbreak in Lazio Region, Italy, 2017.

Background: The latest European Chikungunya virus (CHIKV) outbreak occurred in Italy in 2017, in the municipalities of Anzio and Rome (Lazio Region), with a secondary outbreak in the Calabrian Region. Most CHIKV infections are symptomatic but about 15% of people who acquire the infection may be asymptomatic. A retrospective study was conducted with the aim of assessing the prevalence of recent/ongoing CHIKV infections on the blood donor population in the Lazio Region, during the 2017 outbreak (including in the period before it was detected). Methods: The study was conducted on 4595 plasma samples from donors who donated in 14 different Blood Establishments in the Lazio Region, in the period June–November 2017. A total of 389 of these samples were collected in provinces not affected by the outbreak and were used as negative controls. All samples were tested for IgM detection by the use of an ELISA test, and positive samples were tested for confirmation through the use of a PRNT. Molecular tests were performed on sera that were found to be IgM-positive or borderline. Results: A total of 41 (0.89%) blood donors tested positive for IgM. None of these positive IgM ELISA results was confirmed either by PRNT or by molecular tests. Conclusions: Our study has shown no evidence of recent/ongoing CHIKV infection in blood donors of the affected area.

Evidence of chikungunya virus infection among febrile patients in northwest Ethiopia

BackgroundChikungunya virus (CHIKV) infection has similar clinical presentations to malaria. Hence, febrile illnesses are often misdiagnosed as malaria. Therefore, this study aimed to generate baseline data on CHIKV infection in northwest Ethiopia where malaria is endemic. MethodsA hospital-based cross-sectional study was conducted among febrile patients presenting at the Metema and Humera Kahsay Abera hospitals from March 2016 to May 2017. Data on socio-demographic, clinical presentations, and possible risk factors were collected using a structured questionnaire. Serum samples were screened for immunoglobulin-M (IgM) and IgG antibodies to CHIKV infections using enzyme-linked immunosorbent assay. Logistic regression analysis was used to determine the strength of association. ResultsOf 586 samples screened, the overall seroprevalence of CHIKV infection was 23%. Of the total study participants, 22.5% had CHIKV-specific IgM, indicating recent CHIKV infection. During monsoon and post-monsoon periods, increased prevalence of anti-CHIKV IgM seropositivity was found. The most common clinical presentation observed was fever, followed by headache and joint pain. Men had twice the likelihood of CHIKV infection. The presence of stagnant water near the residence almost doubled the risk for CHIKV infection. ConclusionsMost of the study participants had recent infection with CHIKV, suggesting the need to design disease prevention and intervention strategies.

Serological Evidence of Chikungunya Virus Infection Among Suspected Measles Cases in Selected Regions of Kenya: 2008-2014.

Chikungunya virus (family Togavirdae and genus Alphavirus) is an emerging and reemerging virus of public health importance both regionally and globally. In Kenya, about 50-60% of the suspected measles cases remain undiagnosed once measles and rubella is ruled out by immunoglobulin M (IgM) ELISA thus prompted the need to do differential diagnosis on the measles/rubella negative samples. Nothing is known about the role played by chikungunya infection among these suspected measles cases. Febrile rash illness is a common clinical presentation of arboviruses, including chikungunya. In this study, we conducted a serosurvey to explore the possible role of chikungunya infections among suspected measles cases in Kenya that had tested negative for measles and rubella. Sera were tested by commercially available ELISA for the presence of IgG and IgM antibodies against the chikungunya virus. All positive samples for chikungunya by ELISA were confirmed by plaque reduction neutralization test (PRNT), and to rule out cross-reactivity with other alphaviruses a panel of viruses was used, namely o' nyong' nyong, Semliki Forest, and Sindbis viruses. Of the 392 serum samples screened, 0.3% (n = 1) tested positive for IgM antibodies, while 4.6% (n = 18) tested positive for IgG antibodies against the chikungunya virus. PRNT results indicated 2 (11%) chikungunya positives and 7 (38.9%) o' nyong' nyong positives. We recommend awareness among health care providers and improved surveillance for these arboviruses by both serology and molecular testing. Testing for other pathogens should also be done to improve disease detection and diagnosis.

Seroprevalence and Symptomatic Attack Rate of Chikungunya Virus Infection, United States Virgin Islands, 2014-2015.

When introduced into a naïve population, chikungunya virus generally spreads rapidly, causing large outbreaks of fever and severe polyarthralgia. We randomly selected households in the U.S. Virgin Islands (USVI) to estimate seroprevalence and symptomatic attack rate for chikungunya virus infection at approximately 1 year following the introduction of the virus. Eligible household members were administered a questionnaire and tested for chikungunya virus antibodies. Estimated proportions were calibrated to age and gender of the population. We enrolled 509 participants. The weighted infection rate was 31% (95% confidence interval [CI]: 26-36%). Among those with evidence of chikungunya virus infection, 72% (95% CI: 65-80%) reported symptomatic illness and 31% (95% CI: 23-38%) reported joint pain at least once per week approximately 1 year following the introduction of the virus to USVI. Comparing rates from infected and noninfected study participants, 70% (95% CI: 62-79%) of fever and polyarthralgia and 23% (95% CI: 9-37%) of continuing joint pain in patients infected with chikungunya virus were due to their infection. Overall, an estimated 43% (95% CI: 33-52%) of the febrile illness and polyarthralgia in the USVI population during the outbreak was attributable to chikungunya virus and only 12% (95% CI: 7-17%) of longer term joint pains were attributed to chikungunya virus. Although the rates of infection, symptomatic disease, and longer term joint symptoms identified in USVI are similar to other outbreaks of the disease, a lower proportion of acute fever and joint pain was found to be attributable to chikungunya virus.

Investigation of an autochthonous chikungunya outbreak, July–September 2017, France

Introduction Chikungunya virus (CHIKV) is an arbovirus that threatens Europe through irreversible spread of vector mosquito Aedes albopictus. In mainland France, three CHIKV local transmission episodes were detected in the last years by sustained surveillance. This surveillance is integrated in a national preparedness and control plan. In August 2017, a real-time reverse transcription-polymerase chain reaction (RT-PCR) confirmed autochthonous case of chikungunya was notified in the Var department, (southeastern France) in the town of Le Cannet-des-Maures (LCDM). Epidemiological and entomological investigations were immediately implemented to determine the source of infection and the extent of the transmission of the CHIKV in order to guide control measures. While these investigations were ongoing, in September, a second episode occurred in Taradeau, a town located ten kilometres from LCDM. Due to the spatial and temporal proximities of these episodes, investigations were also implemented with the additional objective to explore a potential link between them. Methods We conducted door-to-door case-finding in all households within a 200 m-radius around the autochthonous cases’ dwellings. The aim of these investigations was to identify and test any person with symptoms compatible with CHIKV infection, among households’ members as well as visiting relatives or friends, in order to determine the source of infection and the possible link between clusters. We contacted general practitioners (GP), medical laboratories and emergency services in both towns and their surroundings, to request them to quickly report and test any patient with symptoms compatible with CHIKV infection since June 1st. In the same time, we reviewed the surveillance database looking for a possible primary case among the imported chikungunya cases notified at local and national level. For any person with symptoms compatible with CHIKV infection, blood samples were collected and tested for CHIKV infection (RT-PCR and/or serology). Molecular analyses were performed by the National Reference Laboratory on index cases for each transmission episode. Entomological prospections and vector-control measures were implemented in the area of the investigation. Results Eleven cases (seven confirmed by RT-PCR and four with serological evidence of CHIKV infection) were identified in LCDM. Six cases (two confirmed by RT-PCR and four with serological evidence of CHIKV infection) were identified in Taradeau. The surveillance database reviewing has failed to identify imported chikungunya case living or travelling in the Var department. However, thanks to door-to-door investigations, we identified the primary case and a case who was the epidemiological link between the two clusters. All cases had occurred within 60 days after the onset of symptoms of the primary case (July 11th). Genomic characterisation of the virus identified for both clusters the same strain belonging to the “East Central South African” (ECSA) lineage and carrying the adaptive mutation A226 V facilitating transmission by Ae. Albopictus. Despite unfavourable weather conditions, entomological prospections in both towns, detected the presence of adult mosquitoes and breeding sites attributable to a high number of rainwater storage tank in the neighbourhoods. Conclusions This outbreak is the third occurrence in France of local transmission of CHIKV. The two largest episodes involved an ECSA genotype CHIKV harbouring the A226 V mutation facilitating transmission by Ae. albopictus. Thanks to previous information campaigns directed at physicians and biologists, the outbreak was detected early enough to timely implement vector-control measures and to limit its spread. This new outbreak confirms that CHIKV represents an increasing threat in Europe. Regular awareness campaigns targeting physicians and biologists, focusing on arboviruses diagnosis and reporting, have to be conducted to improve the effectiveness of this surveillance.

Evidence of chikungunya virus infection among febrile patients seeking healthcare in selected districts of Tanzania

ABSTRACTIntroduction: Chikungunya virus (CHIKV) infection is an emerging mosquito-borne disease that has been associated with frequent epidemics in the world. However, there is a dearth of information on its magnitude and associated risk factors in Tanzania.Objective: A study was conducted to determine seroprevalence of CHIKV among febrile patients seeking medical care at health facilities in Karagwe, Sengerema, Kilombero and Kyela districts.Methods: Structured questionnaires were administered and 728 serum samples were collected between May and June, 2015 and tested for the presence of CHIKV-IgM and IgG-specific antibodies using Enzyme-linked immunosorbent assay.Results and discussion: The common clinical characteristics exhibited by outpatients were fever, headache and joint pains (100%, 70%, and 68.3% respectively). Out of 728 outpatients screened for CHIKV, 105 (14%) tested CHIKV IgG positive whilst 11 (1.5%) tested CHIKV IgM positive. Chikungunya seropositivity was significantly higher than previously reported in Tanzania. The most affected age group was 20–29 years. Our results indicate that CHIKV infection is prevalent and contributes to the burden of febrile illnesses in Tanzania. The seroprevalence varies between districts, reflecting variation in mosquito vector transmission dynamics in different parts of the country.Abbreviations: CHIKV: Chikungunya virus; EDTA: Ethylenediaminetetraacetic acid; ELISA: Enzyme-linked immunosorbent assay; IgG: Immunoglobulin G; IgM: Immunoglobulin M; NIMR: National Institute for Medical Research; RU: Relative Units; SACIDS: Southern African Centre for Infectious Disease Surveillance; USA: United States of America

Chikungunya Outbreak in Kedougou, Southeastern Senegal in 2009–2010

BackgroundIn Senegal, Chikungunya virus (CHIKV), which is an emerging mosquito-borne alphavirus, circulates in a sylvatic and urban/domestic cycle and has caused sporadic human cases and epidemics since 1960s. However, the real impact of the CHIKV sylvatic cycle in humans and mechanisms underlying its emergence still remains unknown.MethodologyOne thousand four hundred nine suspect cases of CHIKV infection, recruited from 5 health facilities located in Kedougou region, south-eastern Senegal, between May 2009 to March 2010, together with 866 serum samples collected from schoolchildren from 4 elementary schools in May and November 2009 from Kedougou were screened for anti-CHIKV immunoglobulin (Ig)M antibodies and, when appropriate, for viral nucleic acid by real-time polymerase chain reaction (rPCR) and virus isolation. In addition, mosquitoes collected in the same area from May 2009 to January 2010 were tested for CHIKV by rPCR and by virus isolation, and 116 monkeys sera collected from March 2010 to May 2010 were tested for anti-CHIKV IgM and neutralizing antibodies.ResultsThe main clinical manifestations of the CHIKV suspect cases were headache, myalgia, and arthralgia. Evidence for CHIKV infection was observed in 1.4% (20 of 1409) of patients among suspect cases. No significant difference was observed among age or sex groups. In addition, 25 (2.9%) students had evidence of CHIKV infection in November 2009. Chikungunya virus was detected in 42 pools of mosquitoes, mainly from Aedes furcifer, and 83% of monkeys sampled were seropositive.ConclusionsOur findings further documented that CHIKV is maintained in a sylvatic transmission cycle among monkeys and Aedes mosquitoes in Kedougou, and humans become infected by exposure to the virus in the forest.

Use of Household Cluster Investigations to Identify Factors Associated with Chikungunya Virus Infection and Frequency of Case Reporting in Puerto Rico.

BackgroundChikungunya virus (CHIKV) is transmitted by Aedes species mosquitoes and is the cause of an acute febrile illness characterized by potentially debilitating arthralgia. After emerging in the Caribbean in late 2013, the first locally-acquired case reported to public health authorities in Puerto Rico occurred in May 2014. During June–August 2014, household-based cluster investigations were conducted to identify factors associated with infection, development of disease, and case reporting.Methodology/Principal FindingsResidents of households within a 50-meter radius of the residence of laboratory-positive chikungunya cases that had been reported to Puerto Rico Department of Health (PRDH) were offered participation in the investigation. Participants provided a serum specimen and answered a questionnaire that collected information on demographic factors, household characteristics, recent illnesses, healthcare seeking behaviors, and clinical diagnoses. Current CHIKV infection was identified by rRT-PCR, and recent CHIKV infection was defined by detection of either anti-CHIKV IgM or IgG antibody. Among 250 participants, 74 (30%) had evidence of CHIKV infection, including 12 (5%) with current and 62 (25%) with recent CHIKV infection. All specimens from patients with CHIKV infection that were collected within four days, two weeks, and three weeks of illness onset were positive by RT-PCR, IgM ELISA, and IgG ELISA, respectively. Reporting an acute illness in the prior three months was strongly associated with CHIKV infection (adjusted odds ratio [aOR] = 21.6, 95% confidence interval [CI]: 9.24–50.3). Use of air conditioning (aOR = 0.50, 95% CI = 0.3–0.9) and citronella candles (aOR = 0.4, 95% CI = 0.1–0.9) were associated with protection from CHIKV infection. Multivariable analysis indicated that arthralgia (aOR = 51.8, 95% CI = 3.8–700.8) and skin rash (aOR = 14.2, 95% CI = 2.4–84.7) were strongly associated with CHIKV infection. Hierarchical cluster analysis of signs and symptoms reported by CHIKV-infected participants demonstrated that fever, arthralgia, myalgia, headache, and chills tended to occur simultaneously. Rate of symptomatic CHIKV infection (defined by arthralgia with fever or skin rash) was 62.5%. Excluding index case-patients, 22 (63%) participants with symptomatic CHIKV infection sought medical care, of which 5 (23%) were diagnosed with chikungunya and 2 (9%) were reported to PRDH.Conclusions/SignificanceThis investigation revealed high rates of CHIKV infection among household members and neighbors of chikungunya patients, and that behavioral interventions such as use of air conditioning were associated with prevention of CHIKV infection. Nearly two-thirds of patients with symptomatic CHIKV infection sought medical care, of which less than one-quarter were reportedly diagnosed with chikungunya and one-in-ten were reported to public health authorities. These findings emphasize the need for point-of-care rapid diagnostic tests to optimize identification and reporting of chikungunya patients.

Chikungunya outbreak in Bueng Kan Province, Thailand, 2013.

Chikungunya outbreak in Bueng Kan Province, Thailand, 2013.

First evidence of chikungunya virus infection in Assam, Northeast India

During June-September 2008, an illness characterized by fever, headache and joint pain was reported in Assam state, northeast India. It presented characteristic features resembling chikungunya or dengue virus infection based on clinical symptoms. Dengue and chikungunya IgM antibody was detected in 10.0% (28/280) and 3.6% (10/280) patients respectively. The chikungunya positive patients did not travel to and from any endemic region confirming indigenous transmission. Persistent arthralgia and hearing loss has been observed in a recovered patient. Entomological surveys revealed the presence of vectors viz. Aedes aegypti and Aedes albopictus. This is the maiden report of chikungunya occurrence in Northeast India.