Cases Of Zika Virus Disease Research Articles

Identification of the first Zika virus disease case following the detection in Aedes aegypti from Karnataka state, India.

Identification of the first Zika virus disease case following the detection in Aedes aegypti from Karnataka state, India.

West Nile Virus and Other Nationally Notifiable Arboviral Diseases - United States, 2021.

Arthropod-borne viruses (arboviruses) are transmitted to humans primarily through the bites of infected mosquitoes or ticks, and in the continental United States, West Nile virus (WNV) is the leading cause of domestically acquired arboviral disease. Other arboviruses cause sporadic cases of disease as well as occasional outbreaks. This report summarizes 2021 surveillance data reported to CDC by U.S. jurisdictions for nationally notifiable arboviruses; the report excludes chikungunya, dengue, yellow fever, and Zika virus disease cases, because these infections were acquired primarily through travel during 2021. Forty-nine states and the District of Columbia reported 3,035 cases of domestic arboviral disease, including those caused by West Nile (2,911), La Crosse (40), Jamestown Canyon (32), Powassan (24), St. Louis encephalitis (17), unspecified California serogroup (six), and eastern equine encephalitis (five) viruses. Among the WNV disease cases, 2,008 (69%) were classified as neuroinvasive disease, for a national incidence of 0.61 cases per 100,000 population. Because arboviral diseases continue to cause serious illness, maintaining surveillance programs to monitor their transmission and prevalence is important to the direction and promotion of prevention activities. Health care providers should consider arboviral infections in the differential diagnosis of aseptic meningitis and encephalitis, obtain appropriate specimens for laboratory testing, and promptly report cases to public health authorities. Prevention depends on community and household efforts to reduce vector populations and personal protective measures to prevent mosquito and tick bites, such as use of Environmental Protection Agency-registered insect repellent and wearing protective clothing.

Arthropod-borne diseases among travellers arriving in Europe from Africa, 2015 to 2019.

BackgroundTravellers are generally considered good sentinels for infectious disease surveillance.AimTo investigate whether health data from travellers arriving from Africa to Europe could provide evidence to support surveillance systems in Africa.MethodsWe examined disease occurrence and estimated risk of infection among travellers arriving from Africa to Europe from 2015 to 2019 using surveillance data of arthropod-borne disease cases collected through The European Surveillance System (TESSy) and flight passenger volumes from the International Air Transport Association.ResultsMalaria was the most common arthropod-borne disease reported among travellers from Africa, with 34,235 cases. The malaria travellers' infection rate (TIR) was 28.8 cases per 100,000 travellers, which is 36 and 144 times higher than the TIR for dengue and chikungunya, respectively. The malaria TIR was highest among travellers arriving from Central and Western Africa. There were 956 and 161 diagnosed imported cases of dengue and chikungunya, respectively. The highest TIR was among travellers arriving from Central, Eastern and Western Africa for dengue and from Central Africa for chikungunya in this period. Limited numbers of cases of Zika virus disease, West Nile virus infection, Rift Valley fever and yellow fever were reported.ConclusionsDespite some limitations, travellers' health data can efficiently complement local surveillance data in Africa, particularly when the country or region has a sub-optimal surveillance system. The sharing of anonymised traveller health data between regions/continents should be encouraged.

Spatial, Sociodemographic, and Weather Analysis of the Zika Virus Outbreak: U.S. Virgin Islands, January 2016-January 2018.

Background: The first Zika virus outbreak in U.S. Virgin Islands identified 1031 confirmed noncongenital Zika disease (n = 967) and infection (n = 64) cases during January 2016-January 2018; most cases (89%) occurred during July-December 2016. Methods and Results: The epidemic followed a continued point-source outbreak pattern. Evaluation of sociodemographic risk factors revealed that estates with higher unemployment, more houses connected to the public water system, and more newly built houses were significantly less likely to have Zika virus disease and infection cases. Increased temperature was associated with higher case counts, which suggests a seasonal association of this outbreak. Conclusion: Vector surveillance and control measures are needed to prevent future outbreaks.

Estimating Zika virus attack rates and risk of Zika virus-associated neurological complications in Colombian capital cities with a Bayesian model.

Zika virus (ZIKV) is a mosquito-borne pathogen that caused a major epidemic in the Americas in 2015-2017. Although the majority of ZIKV infections are asymptomatic, the virus has been associated with congenital birth defects and neurological complications (NC) in adults. We combined multiple data sources to improve estimates of ZIKV infection attack rates (IARs), reporting rates of Zika virus disease (ZVD) and the risk of ZIKV-associated NC for 28 capital cities in Colombia. ZVD surveillance data were combined with post-epidemic seroprevalence data and a dataset on ZIKV-associated NC in a Bayesian hierarchical model. We found substantial heterogeneity in ZIKV IARs across cities. The overall estimated ZIKV IAR across the 28 cities was 0.38 (95% CrI: 0.17-0.92). The estimated ZVD reporting rate was 0.013 (95% CrI: 0.004-0.024), and 0.51 (95% CrI: 0.17-0.92) cases of ZIKV-associated NC were estimated to be reported per 10 000 ZIKV infections. When we assumed the same ZIKV IAR across sex or age group, we found important spatial heterogeneities in ZVD reporting rates and the risk of being reported as a ZVD case with NC. Our results highlight how additional data sources can be used to overcome biases in surveillance data and estimate key epidemiological parameters.

Descriptive analysis of surveillance data for Zika virus disease and Zika virus-associated neurological complications in Colombia, 2015–2017

Zika virus (ZIKV) is a mosquito-borne pathogen that recently caused a major epidemic in the Americas. Although the majority of ZIKV infections are asymptomatic, the virus has been associated with birth defects in fetuses and newborns of infected mothers as well as neurological complications in adults. We performed a descriptive analysis on approximately 106,000 suspected and laboratory-confirmed cases of Zika virus disease (ZVD) that were reported during the 2015-2017 epidemic in Colombia. We also analyzed a dataset containing patients with neurological complications and recent febrile illness compatible with ZVD. Females had higher cumulative incidence of ZVD than males. Compared to the general population, cases were more likely to be reported in young adults (20 to 39 years of age). We estimated the cumulative incidence of ZVD in pregnant females at 3,120 reported cases per 100,000 population (95% CI: 3,077-3,164), which was considerably higher than the incidence in both males and non-pregnant females. ZVD cases were reported in all 32 departments. Four-hundred and eighteen patients suffered from ZIKV-associated neurological complications, of which 85% were diagnosed with Guillain-Barré syndrome. The median age of ZIKV cases with neurological complications was 12 years older than that of ZVD cases. ZIKV-associated neurological complications increased with age, and the highest incidence was reported among individuals aged 75 and older. Even though neurological complications and deaths due to ZIKV were rare in this epidemic, better risk communication is needed for people living in or traveling to ZIKV-affected areas.

Case Series of Laboratory-Associated Zika Virus Disease, United States, 2016-2019.

Zika virus diagnostic testing and laboratory research increased considerably when Zika virus began spreading through the Americas in 2015, increasing the risk for potential Zika virus exposure of laboratory workers and biomedical researchers. We report 4 cases of laboratory-associated Zika virus disease in the United States during 2016–2019. Of these, 2 were associated with needlestick injuries; for the other 2 cases, the route of transmission was undetermined. In laboratories in which work with Zika virus is performed, good laboratory biosafety practices must be implemented and practiced to reduce the risk for infection among laboratory personnel.

Epidemiologic and spatiotemporal trends of Zika Virus disease during the 2016 epidemic in Puerto Rico.

BackgroundAfter Zika virus (ZIKV) emerged in the Americas, laboratory-based surveillance for arboviral diseases in Puerto Rico was adapted to include ZIKV disease.Methods and findingsSuspected cases of arboviral disease reported to Puerto Rico Department of Health were tested for evidence of infection with Zika, dengue, and chikungunya viruses by RT-PCR and IgM ELISA. To describe spatiotemporal trends among confirmed ZIKV disease cases, we analyzed the relationship between municipality-level socio-demographic, climatic, and spatial factors, and both time to detection of the first ZIKV disease case and the midpoint of the outbreak. During November 2015–December 2016, a total of 71,618 suspected arboviral disease cases were reported, of which 39,717 (55.5%; 1.1 cases per 100 residents) tested positive for ZIKV infection. The epidemic peaked in August 2016, when 71.5% of arboviral disease cases reported weekly tested positive for ZIKV infection. Incidence of ZIKV disease was highest among 20–29-year-olds (1.6 cases per 100 residents), and most (62.3%) cases were female. The most frequently reported symptoms were rash (83.0%), headache (64.6%), and myalgia (63.3%). Few patients were hospitalized (1.2%), and 13 (<0.1%) died. Early detection of ZIKV disease cases was associated with increased population size (log hazard ratio [HR]: -0.22 [95% confidence interval -0.29, -0.14]), eastern longitude (log HR: -1.04 [-1.17, -0.91]), and proximity to a city (spline estimated degrees of freedom [edf] = 2.0). Earlier midpoints of the outbreak were associated with northern latitude (log HR: -0.30 [-0.32, -0.29]), eastern longitude (spline edf = 6.5), and higher mean monthly temperature (log HR: -0.04 [-0.05, -0.03]). Higher incidence of ZIKV disease was associated with lower mean precipitation, but not socioeconomic factors.ConclusionsDuring the ZIKV epidemic in Puerto Rico, 1% of residents were reported to public health authorities and had laboratory evidence of ZIKV disease. Transmission was first detected in urban areas of eastern Puerto Rico, where transmission also peaked earlier. These trends suggest that ZIKV was first introduced to Puerto Rico in the east before disseminating throughout the island.

Public Health Response to Zika Virus Exposure of Air Force Members Deployed to Caribbean Islands, 2016.

The emergence of Zika virus disease (ZVD) in areas of military operations provided a new opportunity for force health protection. ZVD infection had an estimated 4:1 asymptomatic-to-symptomatic ratio and can cause neurologic sequelae. We provide a brief report of a field investigation utilizing laboratory-based surveillance and survey instruments to characterize ZVD risk among personnel deployed to the Dominican Republic in support of Operation NEW HORIZONS (NH). Additionally, we describe a cluster of 3 ZVD cases among 8 aircrew on a short mission to St. Croix (U.S. Virgin Islands). Following Operation NH, 6 of a total 189 deployed cohort members tested positive for ZVD by immunoglobulin M and confirmatory plaque reduction neutralization test (3.2%). Reverse transcription polymerase chain reaction testing in urine or serum was positive in 4 of those 6 cases. All 6 cases reported at least one symptom, with 5 reporting subjective fever and arthralgia and 4 reporting rash. Cases were less likely to have air-conditioned living quarters (odds ratio=0.1; 95% confidence interval 0.02-0.77; P<0.03), but were otherwise similar to non-cases. Likewise, in St. Croix, 3/8 tested positive by immunoglobulin M and plaque reduction neutralization test for an attack rate of 38%. Similar to Operation NH, all three cases were symptomatic with subjective fever (67%), arthralgia (67%), and/or rash (100%). This field investigation identified differing, mission location-dependent ZVD attack rates and a 0:9 asymptomatic-to-symptomatic case ratio. As this was unexpected based on a previous report of a 4:1 ratio, it emphasizes the need to be cautious before generalizing outbreak characteristics between populations while also offering additional practical experience for force health protection.

Zika Virus Disease in Colombia — Preliminary Report

BackgroundColombia began official surveillance for Zika virus disease (ZVD) in August 2015. In October 2015, an outbreak of ZVD was declared after laboratory-confirmed disease was identified in nine patients.MethodsUsing the national population-based surveillance system, we assessed patients with clinical symptoms of ZVD from August 9, 2015, to April 2, 2016. Laboratory test results and pregnancy outcomes were evaluated for a subgroup of pregnant women. Concurrently, we investigated reports of microcephaly for evidence of congenital ZVD.ResultsBy April 2, 2016, there were 65,726 cases of ZVD reported in Colombia, of which 2485 (4%) were confirmed by means of reverse-transcriptase–polymerase-chain-reaction (RT-PCR) assay. The overall reported incidence of ZVD among female patients was twice that in male patients. A total of 11,944 pregnant women with ZVD were reported in Colombia, with 1484 (12%) of these cases confirmed on RT-PCR assay. In a subgroup of 1850 pregnant women, more than 90% of women who were reportedly infected during the third trimester had given birth, and no infants with apparent abnormalities, including microcephaly, have been identified. A majority of the women who contracted ZVD in the first or second trimester were still pregnant at the time of this report. Among the cases of microcephaly investigated from January 2016 through April 2016, four patients had laboratory evidence of congenital ZVD; all were born to asymptomatic mothers who were not included in the ZVD surveillance system.ConclusionsPreliminary surveillance data in Colombia suggest that maternal infection with the Zika virus during the third trimester of pregnancy is not linked to structural abnormalities in the fetus. However, the monitoring of the effect of ZVD on pregnant women in Colombia is ongoing. (Funded by Colombian Instituto Nacional de Salud and the Centers for Disease Control and Prevention.)

Repercussions of Zika virus emergency on the health of the population of Tocantins state, Brazil, 2015 and 2016: a descriptive study.

Objective To describe the occurrence of Zika virus disease and its complications in the state of Tocantins and in its capital, the city of Palmas. Methods This was a descriptive study using data from health information systems. Results Incidence of reported Zika virus disease cases in 2015 and 2016 was 295.2/100,000 inhabitants and 411.1/100,000 inhab. in the general population, and 5.9/1,000 and 27.8/1,000 live births, respectively. Higher risks occurred in women, the 20-39 year age group, municipalities in the central and northwestern regions of the state and in hotter months (February and March). Incidence of Zika-related microcephaly during pregnancy was 0.06/1,000 live births. One case of Guillain-Barré Syndrome resulting from Zika virus infection was confirmed. Conclusion Zika virus disease hit Tocantins intensely, although its adverse outcomes were less frequent than in other states.

Human Vaginal Epithelial Cells are Susceptible to the Zika Virus: Implications for Zika Vaginal Transmission

The Zika Virus (ZIKV) is an emerging RNA virus that cause congenital birth defects and neurological compilations among infected individuals. Since the 2015 ZIKV outbreak in Brazil, the Centers for Disease Control, and Prevention (CDC) reports over 35,000 cases ZIKV disease cases within the United States (US) and US territories. Although ZIKV is primarily transmitted through an infected Aedes mosquito, recent studies demonstrate this pathogenic virus can be transmitted via sexual contact with an infected partner. CDC confirmed multiple clinical cases of infected patients acquired ZIKV through sexual transmission within the US. Additionally, mounting evidence from animal and cell studies demonstrate that the female reproductive tract supports ZIKV replication following intravaginal exposure. Despite the growing evidence associating ZIKV to sexual transmission, the underlying molecular mechanism involving vaginal transmission remains elusive. The overarching goal is to examine the role of the vaginal tract in ZIKV sexual transmission on a molecular level. The vaginal tract has multiple layers of epithelial cells that constitutes as the first line of defense against foreign pathogens. Given the capacity of sexual intercourse, we hypothesize that the initial event for ZIKV vaginal transmission is most likely through direct viral uptake at the outermost epithelial layer of the vaginal tract. We aim to test our hypothesis by (1) characterizing the replication kinetics of ZIKV in human vaginal epithelial cells (hVECs) in vitro and (2) determining the functional role of the putative ZIKV entry receptor, AXL, in hVECs. Our recent findings indicate hVECs is a permissive cell target for local ZIKV replication and production. Vaginal infection resulted in de novo replication of the ZIKV RNA genome, active production of the viral envelope protein, and steady release of infectious viral particles. Cell viability studies further indicate that hVECs do not exhibit significant cytopathic effect following ZIKV exposure. Additional studies show that the flaviviral entry receptor AXL is endogenously expressed in hVECs on a protein, mRNA level, and surface level. When expression patterns were compared between Vero and 293T cell lines, our results show similar protein levels of endogenous AXL in both Vero and VK2E6E7 cell lines, which may suggest that ZIKV entry via AXL‐mediated pathway and the dynamics of viral growth act independently of one another during sexual transmission. Our AXL knockdown and overexpression studies validate that this tyrosine receptor kinase is involved in ZIKV vaginal entry. In the future, kinase inhibitory studies will be performed to further validate whether downstream signaling contributes to ZIKV replication and production in hVECs. The outcome of this research will provide further insight into host‐virus interactions on a molecular level, which can lead to devising therapeutic agents aimed at interfering with the pathology caused by the virus.Support or Funding Information• T32 Grant: NIH National Heart, Lung, and Blood Institute, Research Training in Cardiovascular Biology at Meharry

Vector-borne transmission of Zika virus in Europe, southern France, August 2019.

On 1 October 2019, a locally-acquired Zika virus disease case was laboratory confirmed in Hyères, Var department. Active case finding identified two additional locally-acquired cases living within 90 m, with symptom onset 8 days before the index case. Extensive patient interviews did not yield information supporting transmission through sexual contact or substances of human origin. Vector-borne transmission by local Aedes albopictus mosquitoes is the most likely mode of transmission. Here we describe the public health response.

Epidemiology of Dengue, Chikungunya, and Zika Virus Disease in U.S. States and Territories, 2017

Dengue, chikungunya, and Zika viruses, primarily transmitted by Aedes species mosquitoes, have caused large outbreaks in the Americas, leading to travel-associated cases and local mosquito-borne transmission in the United States. We describe the epidemiology of dengue, chikungunya, and noncongenital Zika virus disease cases reported from U.S. states and territories in 2017, including 971 dengue cases, 195 chikungunya cases, and 1,118 Zika virus disease cases. Cases of all three diseases reported from the territories were reported as resulting from local mosquito-borne transmission. Cases reported from the states were primarily among travelers, with only seven locally acquired mosquito-transmitted Zika virus disease cases reported from Texas (n = 5) and Florida (n = 2). In the territories, most dengue cases (n = 508, 98%) were reported from American Samoa, whereas the majority of chikungunya (n = 39, 100%) and Zika virus disease (n = 620, 93%) cases were reported from Puerto Rico. Temporally, the highest number of Zika virus disease cases occurred at the beginning of the year, followed by a sharp decline, mirroring decreasing case numbers across the Americas following large outbreaks in 2015 and 2016. Dengue and chikungunya cases followed a more seasonal pattern, with higher case numbers from July through September. Travelers to the United States and residents of areas with active virus transmission should be informed of both the ongoing risk from dengue, chikungunya, and Zika virus disease and personal protective measures to lower their risk of mosquito bites and to help prevent the spread of these diseases.

Cluster containment strategy: addressing Zika virus outbreak in Rajasthan, India

India is at risk of Zika virus transmission due to high prevalence of its vector Aedes aegypti. Rajasthan, a state in the north-west region of India, has also high prevalence...

Two Cases of Zika Virus Disease Diagnosed After Traveling to Cuba

Two Cases of Zika Virus Disease Diagnosed After Traveling to Cuba

Postnatally Acquired Zika Virus Disease Among Children, United States, 2016-2017.

The clinical findings among children with postnatally acquired Zika virus disease are not well characterized. We describe and compare clinical signs and symptoms for children aged <18 years. Zika virus disease cases were included if they met the national surveillance case definition, had illness onset in 2016 or 2017, resided in a participating state, and were reported to the Centers for Disease Control and Prevention. Pediatric cases were aged <18 years; congenital and perinatal infections were excluded. Pediatric cases were matched to adult cases (18‒49 years). Clinical information was compared between younger and older pediatric cases and between children and adults. A total of 141 pediatric Zika virus disease cases were identified; none experienced neurologic disease. Overall, 28 (20%) were treated in an emergency department, 1 (<1%) was hospitalized; none died. Of the 4 primary clinical signs and symptoms associated with Zika virus disease, 133 (94%) children had rash, 104 (74%) fever, 67 (48%) arthralgia, and 51 (36%) conjunctivitis. Fever, arthralgia, and myalgia were more common in older children (12‒17 years) than younger children (1‒11 years). Arthralgia, arthritis, edema, and myalgia were more common in adults compared to children. This report supports previous findings that Zika virus disease is generally mild in children. The most common symptoms are similar to other childhood infections, and clinical findings and outcomes are similar to those in adults. Healthcare providers should consider a diagnosis of Zika virus infection in children with fever, rash, arthralgia, or conjunctivitis, who reside in or have traveled to an area where Zika virus transmission is occurring.

Zika virus: Epidemiological surveillance of the Mexican Institute of Social Security.

IntroductionAt the end of 2015, the first cases of Zika were identified in southern Mexico. During 2016, Zika spread as an outbreak to a large part of the country's coastal zones.MethodologyThe Zika epidemiological surveillance system records cases with clinical symptoms of Zika virus disease (ZVD) and those confirmed by means of a reverse polymerase chain reaction (RT-PCR) assay. This report includes the suspected and confirmed cases from 2016. Incidence rates were estimated by region and in pregnant women based on the proportion of confirmed cases.ResultsIn total, 43,725 suspected cases of ZVD were reported. The overall incidence of suspected cases of ZVD was 82.0 per 100,000 individuals and 25.3 per 100,000 Zika cases. There were 4,168 pregnant women with suspected symptoms of ZVD, of which infection was confirmed in 1,082 (26%). The estimated incidence rate of ZVD for pregnant women nationwide was 186.1 positive Zika cases per 100,000 pregnant women.ConclusionsThe incidence of Zika in Mexico is higher than that reported previously in the National System of Epidemiological Surveillance. Positive cases of Zika must be estimated and reported.

An Evolutionary Insight into Zika Virus Strains Isolated in the Latin American Region.

Zika virus (ZIKV) is an emerging pathogen member of the Flaviviridae family. ZIKV has spread rapidly in the Latin American region, causing hundreds of thousands of cases of ZIKV disease, as well as microcephaly in congenital infections. Detailed studies on the pattern of evolution of ZIKV strains have been extremely important to our understanding of viral survival, fitness, and evasion of the host’s immune system. For these reasons, we performed a comprehensive phylogenetic analysis of ZIKV strains recently isolated in the Americas. The results of these studies revealed evidence of diversification of ZIKV strains circulating in the Latin American region into at least five different genetic clusters. This diversification was also reflected in the different trends in dinucleotide bias and codon usage variation. Amino acid substitutions were found in E and prM proteins of the ZIKV strains isolated in this region, revealing the presence of novel genetic variants circulating in Latin America.

GeoSentinel - A surveillance network of returning travelers and migrants

GeoSentinel is an emerging infectious disease network created as a joint project between the International Society of Travel Medicine (ISTM) and the U.S. Centers for Disease Control and Prevention (CDC). GeoSentinel has several major objectives including conducting surveillance for emerging infectious diseases; rapidly sharing novel data on emerging infections with participating sites, internet information services (e.g. ProMED), and public health authorities (e.g. CDC, ECDC, Public Health Agency of Canada); and analyzing, presenting, and publishing surveillance results collaboratively with CDC, GeoSentinel sites, and GeoSentinel's two regional subnetworks, CanTravNet and EuroTravNet. The GeoSentinel surveillance network provides robust data that defines the spectrum of illness and its relation to place of exposure for significant health risks facing travelers and migrants. There are currently 70 GeoSentinel sites in 30 countries and 210 Affiliate Members with a presence on every continent except Antarctica. The GeoSentinel database now contains nearly 300,000 patient records; these include 54% post-travel visits, 31% seen during travel, and 15% migrants. GeoSentinel has successfully identified new outbreaks over the last two decades including leptospirosis in participants in the Borneo Ecochallenge (2000), sarcocystis in travelers to Tionan Island, Malaysia (2010), an outbreak of dengue fever in Angola (2013), schistosomiasis in vacationers in Corsica (2014), and sentinel cases of Zika virus disease in Costa Rica (2016), Vietnam (2016), and several other destinations in Southeast Asia and the South Pacific in recent years. GeoSentinel has also characterized the risk for travelers to countries where major sporting events were planned such as the 2016 Summer Olympics in Brazil. In summary, GeoSentinel is a vibrant global surveillance system that has made important contributions to the identification of disease outbreaks and trends in infectious disease epidemiology among travelers and migrants. In addition, GeoSentinel has the potential, through the development of a biobank of clinical samples, to collaborate with high level laboratories in academia and government to identify new pathogens responsible for respiratory, gastrointestinal, and systemic infections. GeoSentinel translates clinical and epidemiological data into meaningful evidence that is of critical importance to the containment of the global spread of infection.