scholarly journals Serological Evidence of Human Orthohantavirus Infections in Barbados, 2008 to 2016

Pathogens ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 571
Author(s):  
Kirk Osmond Douglas ◽  
Thelma Alafia Samuels ◽  
Rommel Iheozor-Ejiofor ◽  
Olli Vapalahti ◽  
Tarja Sironen ◽  
...  
Keyword(s):  
Rainy Season ◽  
Febrile Illness ◽  
Medical Attention ◽  
Enzyme Linked Immunosorbent Assay ◽  
Serological Evidence ◽  
Rural Parishes ◽  
Peak Transmission ◽  
The Caribbean ◽  
Focus Reduction ◽  
Multiple Pathogen

Background: Hantavirus pulmonary syndrome (HPS) is well-known in South and North America; however, not enough data exist for the Caribbean. The first report of clinical orthohantavirus infection was obtained in Barbados, but no other evidence of clinical orthohantavirus infections among adults in the Caribbean has been documented. Methods: Using enzyme linked immunosorbent assay (ELISA) tests followed by confirmatory testing with immunofluorescent assays (IFA), immunochromatographic (ICG) tests, and pseudotype focus reduction neutralization tests (pFRNT), we retrospectively and prospectively detected orthohantavirus-specific antibodies among patients with febrile illness in Barbados. Results: The orthohantavirus prevalence rate varied from 5.8 to 102.6 cases per 100,000 persons among febrile patients who sought medical attention annually between 2008 and 2016. Two major orthohantavirus epidemics occurred in Barbados during 2010 and 2016. Peak orthohantavisinfectionswere observed during the rainy season (August) and prevalence rates were significantly higher in females than males and in patients from urban parishes than rural parishes. Conclusions: Orthohantavirus infections are still occurring in Barbados and in some patients along with multiple pathogen infections (CHIKV, ZIKV, DENV and Leptospira). Orthohantavirus infections are more prevalent during periods of high rainfall (rainy season) with peak transmission in August; females are more likely to be infected than males and infections are more likely among patients from urban rather than rural parishes in Barbados.

Serological Evidence of Zika Virus Infection in Febrile Patients and Healthy Blood Donors in Sabah, Malaysian Borneo, 2017–2018

2021 ◽  
Author(s):  
Mya Myat Ngwe Tun ◽  
Daisuke Mori ◽  
Shahnaz Binti Sabri ◽  
Omar Kugan ◽  
Saliz Binti Shaharom ◽  
...  
Keyword(s):  
Zika Virus ◽  
Blood Donors ◽  
Neutralization Test ◽  
Febrile Illness ◽  
Healthy Blood Donor ◽  
Serological Evidence ◽  
Serum Samples ◽  
Zikv Infection ◽  
The Caribbean ◽  
Malaysian Borneo

Several Zika virus (ZIKV) seroprevalence studies have been conducted in Africa, Asia, Oceania, the Americas, and the Caribbean. However, studies on ZIKV seroprevalence are limited in Malaysia though several studies have shown that the disease is endemic in the Malaysian state of Sabah. To evaluate the seroprevalence of ZIKV infection, 818 serum samples were collected from febrile patients and healthy blood donors from the Kudat and Kota Kinabalu districts in Sabah from 2017 to 2018. They were screened for ZIKV infection by IgM and IgG ELISA, and positive ZIKV IgM samples were subjected to a 90% neutralization test for confirmation. Twenty-four (6% [95% CI 4 to 8]) confirmed and two (0.5% [95% CI 0.13 to 1.8]) probable ZIKV infections were detected among 400 febrile illness patients. Of 418 healthy blood donor samples, six (1.4% [95% CI 0.65 to 3]) were determined as confirmed ZIKV infections and six (1.4% [95% CI 0.65 to 3]) indicated probable ZIKV infection. This is the first study on the seroprevalence of ZIKV infections among patients and healthy blood donors in Sabah. Compared with previous studies in Malaysia, this study shows that the incidence of ZIKV infection has increased. It also suggests that a sero-surveillance system is essential to determine the circulation of ZIKV in Sabah, Malaysia.

scholarly journals Seroprevalence of chikungunya fever virus and O’nyong Nyong fever virus among febrile patients visiting selected hospitals in 2011-2012 Trans Nzoia County, Kenya

2018 ◽  
Vol 6 (6) ◽  
pp. 1913 ◽  
Author(s):  
Kevin K. Kamau ◽  
Gabriel Magoma ◽  
Allan Ole Kwallah ◽  
Charles K. Syengo ◽  
Matilu Mwau
Keyword(s):  
Neutralizing Antibodies ◽  
Febrile Illness ◽  
Elisa Test ◽  
Health Facilities ◽  
Fever Virus ◽  
Enzyme Linked Immunosorbent Assay ◽  
Cross Sectional ◽  
Western Kenya ◽  
Focus Reduction ◽  
Student’S T

Background: Chikungunya virus (CHIKV) is an alphavirus in the Semliki Forest complex, and is most closely related to O’Nyong Nyong virus (ONNV). CHIKV and ONNV are mosquito-borne alphaviruses endemic in East Africa that cause acute febrile illness and arthralgia. The objectives of this study were to measure seroprevalence of CHIKV and ONNV in selected health facilities in Western Kenya and link it to demographics and other risk factors.Methods: The study design was cross sectional in selected health facilities. We tested for anti-CHIKV antibodies using In-house Indirect IgG Enzyme Linked Immunosorbent Assay (ELISA) and In-house IgM Capture ELISA and confirmed with Focus Reduction Neutralization Test (FRNT) for specific alphavirus neutralizing antibodies against CHIKV or ONNV. Mean, median and standard deviation were used to summarize the data. Comparisons of means and medians were done using Student’s t test. Prevalence rates were determined using descriptive statistics (e.g. proportions, rates).Results: From the 382 samples that were successfully collected, 114 (29.84%) had anti-CHIKV antibodies by the ELISA test. Of these, 27 (7.1%) had CHIKV-specific neutralizing antibodies and 5 (1.3%) had ONNV-specific neutralizing antibodies. Age was significantly associated with seropositivity (OR=1.03; P=0.015, 95% C.I 1.01-1.06). Males were less likely to be seropositive (OR=0.67; P=0.358, 95% C.I 0.27-1.52). Risk factors associated with seropositivity included collecting firewood (OR=2.73 95% 1.13- 6.41) and walls with holes and cracks (OR=0.23 95% C.I 0.04 -0.86).Conclusions: Both CHIKV and ONNV infections were confirmed in the participants’ more so in women and adults, demonstrating undocumented and ongoing transmission in Western Kenya. In 2011 and 2012 CHIKV and ONNV contributed 8.4% of fevers presented in the three selected health facilities in Western Kenya.

scholarly journals Ecological and behavioural risk factors of scrub typhus in central Vietnam: a case-control study

2021 ◽  
Vol 10 (1) ◽  
Author(s):  
Hanh Thi Duc Tran ◽  
Jan Hattendorf ◽  
Hung Manh Do ◽  
Thanh Tien Hoang ◽  
Hang Thi Hai Hoang ◽  
...  
Keyword(s):  
Risk Factors ◽  
Case Control Study ◽  
Scrub Typhus ◽  
Conditional Logistic Regression ◽  
Febrile Illness ◽  
Case Control ◽  
Enzyme Linked Immunosorbent Assay ◽  
Protective Equipment ◽  
Related Factors ◽  
Control Study

Abstract Background The risk factors for scrub typhus in Vietnam remain unknown. Scrub typhus caused by Orientia tsutsugamushi often presents as an undifferentiated febrile illness and remains under appreciated due to the limited availability of diagnostic tests. This tropical rickettsial illness is increasingly recognized as an important cause of non-malaria acute undifferentiated fever in Asia. This study aimed to investigate behavioural and ecological related risk factors of scrub typhus to prevent this potentially life-threatening disease in Vietnam. Methods We conducted a clinical hospital-based active surveillance study, and a retrospective residence-enrolment date-age-matched case–control study in Khanh Hoa province, Vietnam, from August 2018 to March 2020. Clinical examinations, polymerase chain reaction and enzyme-linked immunosorbent assay IgM tests were applied to define cases and controls. All enrolled participants filled out a questionnaire including demographic socio-economic status, personal behaviors/protective equipment, habitat connections, land use, and possible exposure to the vector. Multivariable conditional logistic regression was used to define the scrub typhus associated risk factors. Results We identified 44 confirmed cases and matched them with 152 controls. Among cases and controls, the largest age group was the 41–50 years old and males accounted for 61.4% and 42.8%, respectively. There were similarities in demographic characteristics between the two groups, with the exception of occupation. Several factors were significantly associated with acquisition of scrub typhus, including sitting/laying directly on household floor [adjusted OR (aOR) = 4.9, 95% CI: 1.6–15.1, P = 0.006], household with poor sanitation/conditions (aOR = 7.9, 95% CI: 1.9–32.9, P = 0.005), workplace environment with risk (aOR = 3.0, 95% CI: 1.2–7.6, P = 0.020), always observing mice around home (aOR = 3.7, 95% CI: 1.4–9.9, P = 0.008), and use of personal protective equipment in the field (aOR = 0.4, 95% CI: 0.1–1.1, P = 0.076). Conclusions Ecological and household hygiene-related factors were more associated with scrub typhus infection, than individual-level exposure activities in the hyper-endemic area. These findings support local education and allow people to protect themselves from scrub typhus, especially in areas with limitations in diagnostic capacity. Graphical abstract

scholarly journals Scrub typhus: a hospital-based study in the northern districts of West Bengal, India

2019 ◽  
Vol 7 (6) ◽  
pp. 2403
Author(s):  
Sanjay Kumar Mallick ◽  
Santanu Hazra ◽  
Tanmoy Nandi ◽  
Arunabha Sarkar
Keyword(s):  
Case Fatality Rate ◽  
West Bengal ◽  
Scrub Typhus ◽  
Case Fatality ◽  
Febrile Illness ◽  
Asia Pacific ◽  
Enzyme Linked Immunosorbent Assay ◽  
Acute Febrile Illness ◽  
Fatality Rate ◽  
Serological Tests

Background: Scrub typhus caused by Orientia tsutsugamushi, is a mite-borne zoonotic acute febrile illness. Geographically, it is confined to the Asia-Pacific region and important re-emerging infection in India. Clinical diagnosis of scrub typhus from other acute febrile illness is very difficult due to nonspecific symptoms and the relative absence of eschar in the Indian population. Case fatality rate varies from 30-70% depending on the clinical suspicion, delay in diagnosis and treatment. Antibody-based serological tests are the mainstay of diagnosis. IgM enzyme-linked immunosorbent assay (ELISA) against O. tsutsugamushi is helpful for the diagnosis of scrub typhus within the first week of illness.Methods: The aim of the study was to determine the prevalence of the disease in Northern districts of West Bengal, India using IgM ELISA.Results: Out of 577 serum samples tested 10.05% were positive for IgM antibodies. Majority of cases were below 40 years of age with higher prevalence in female patients. The disease showed a seasonal trend with a peak during the monsoon and later months. The case fatality rate among ELISA positive cases was 32.76%.Conclusions: Significant seropositivity against scrub typhus among cases of acute febrile illness with relatively higher mortality indicates that scrub typhus should be included in the differential diagnosis and confirmed by IgM ELISA.

scholarly journals Unusual Presentation of Chikungunya Virus Infection With Concomintant Erysipelas in a Returning Traveler From the Caribbean: A Case Report

2014 ◽  
Vol 1 (3) ◽  
Author(s):  
Marcos C. Schechter ◽  
Kimberly A. Workowski ◽  
Jessica K. Fairley
Keyword(s):  
United States ◽  
Case Report ◽  
Virus Infection ◽  
Aedes Albopictus ◽  
Chikungunya Virus ◽  
Febrile Illness ◽  
Unusual Presentation ◽  
Chikungunya Fever ◽  
The Caribbean ◽  
Local Transmission

Abstract Chikungunya fever is a mosquito-borne febrile illness caused by Chikungunya virus (CHIKV), an alphavirus from the Togaviridae family. It is transmitted by primarily Aedes aegytpi and Aedes albopictus mosquitos [1]. Once of little importance in the Americas, local transmission was identified in the Caribbean in late 2013. More than 1000 travelers returning to the continental United States have been diagnosed with CHIKV. More importantly, there have been 9 documented cases of autochthonous disease in Florida as of September 16, 2014 [2].

scholarly journals Differences in Antibody Responses against Chelonid Alphaherpesvirus 5 (ChHV5) Suggest Differences in Virus Biology in ChHV5-Seropositive Green Turtles from Hawaii and ChHV5-Seropositive Green Turtles from Florida

2019 ◽  
Vol 94 (4) ◽  
Author(s):  
Thierry M. Work ◽  
Julie Dagenais ◽  
Anna Willimann ◽  
George Balazs ◽  
Kate Mansfield ◽  
...  
Keyword(s):  
Life Histories ◽  
Cross Reactivity ◽  
Tumor Formation ◽  
Enzyme Linked Immunosorbent Assay ◽  
Native Form ◽  
Green Turtles ◽  
Tumor Viruses ◽  
The Caribbean ◽  
Lower Antibody Response

ABSTRACT Fibropapillomatosis (FP) is a tumor disease associated with a herpesvirus (chelonid herpesvirus 5 [ChHV5]) that affects mainly green turtles globally. Understanding the epidemiology of FP has been hampered by a lack of robust serological assays to monitor exposure to ChHV5. This is due in part to an inability to efficiently culture the virus in vitro for neutralization assays. Here, we expressed two glycoproteins (FUS4 and FUS8) from ChHV5 using baculovirus. These proteins were immobilized on enzyme-linked immunosorbent assay plates in their native form and assayed for reactivity to two types of antibodies, full-length 7S IgY and 5.7S IgY, which has a truncated Fc region. Turtles from Florida were uniformly seropositive to ChHV5 regardless of tumor status. In contrast, in turtles from Hawaii, we detected strong antibody reactivity mainly in tumored animals, with a lower antibody response being seen in nontumored animals, including those from areas where FP is enzootic. Turtles from Hawaii actively shedding ChHV5 were more seropositive than nonshedders. In trying to account for differences in the serological responses to ChHV5 between green turtles from Hawaii and green turtles from Florida, we rejected the cross-reactivity of antibodies to other herpesviruses, differences in viral epitopes, or differences in procedure as likely explanations. Rather, behavioral or other differences between green turtles from Hawaii and green turtles from Florida might have led to the emergence of biologically different viral strains. While the strains from turtles in Florida apparently spread independently of tumors, the transmission of the Hawaiian subtype relies heavily on tumor formation. IMPORTANCE Fibropapillomatosis (FP) is a tumor disease associated with chelonid herpesvirus 5 (ChHV5) that is an important cause of mortality in threatened green turtles globally. FP is expanding in Florida and the Caribbean but declining in Hawaii. We show that Hawaiian turtles mount antibodies to ChHV5 mainly in response to tumors, which are the only sites of viral replication, whereas tumored and nontumored Floridian turtles are uniformly seropositive. Tumor viruses that depend on tumors for replication and spread are rare, with the only example being the retrovirus causing walleye dermal sarcoma in fish. The Hawaiian strain of ChHV5 may be the first DNA virus with such an unusual life history. Our findings, along with the fundamental differences in the life histories between Floridian turtles and Hawaiian turtles, may partly explain the differential dynamics of FP between the two regions.

scholarly journals Seroprevalence of Jamestown Canyon virus in the Japanese general population

2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Hirofumi Kato ◽  
Masaaki Satoh ◽  
Madoka Kawahara ◽  
Satoshi Kitaura ◽  
Tomoki Yoshikawa ◽  
...  
Keyword(s):  
General Population ◽  
Human Serum ◽  
Health Agency ◽  
Febrile Illness ◽  
Central Nervous System Disease ◽  
Enzyme Linked Immunosorbent Assay ◽  
Antibody Assay ◽  
Serum Samples ◽  
Human Serum Samples ◽  
Jamestown Canyon Virus

Abstract Background Jamestown Canyon virus (JCV) is a mosquito-borne orthobunyavirus that causes acute febrile illness, meningitis, and meningoencephalitis, mainly among adults. JCV is widely distributed in North America and the number of JCV cases in the U.S. has increased in recent years. Therefore, the central nervous system disease caused by JCV can be considered a potentially re-emerging viral disease. However, the seroprevalence of JCV is unknown in Japan. The purpose of this study is to evaluate the seroprevalence of JCV in the Japanese population. Methods We used an IgG enzyme-linked immunosorbent assay (IgG-ELISA) with JCV-infected cell-lysates and/or a neutralizing (NT) antibody assay. The cut-off value of IgG-ELISA was determined using IgG-ELISA to analyze serum specimens from 37 healthy Japanese donors. IgG-ELISA was validated by assessing its sensitivity and specificity, using 38 human serum samples previously tested for the presence or absence of antibodies against JCV and snowshoe hare virus (SSHV), in an in-house NT antibody assay conducted by the Public Health Agency of Canada. The seroepidemiological study was performed using IgG-ELISA and NT antibody assay to analyze 246 human serum samples from the serum bank of the National Institute of Infectious Diseases (NIID) in Japan. Results The cut-off value of IgG-ELISA was determined at 0.20, based on the mean (− 0.075) and standard deviation (0.092) values using Japanese donors’ sera. The sensitivity and the specificity of IgG-ELISA determined using 25 JCV-positive and 4 JCV-negative serum samples were 96 and 100%, respectively. Analysis of the 246 Japanese serum samples revealed that no specimen showed a higher value than the cut-off value of IgG-ELISA, and no sample tested positive by the NT antibody assay. Conclusions Our results showed that JCV is not circulating significantly in Japan. To the best of our knowledge, this is the first report to demonstrate the seroprevalence of JCV in the general population in Japan.

scholarly journals Dengue Fever and Severe Dengue in Barbados, 2008–2016

2020 ◽  
Vol 5 (2) ◽  
pp. 68
Author(s):  
Kirk Osmond Douglas ◽  
Sudip Kumar Dutta ◽  
Byron Martina ◽  
Fatih Anfasa ◽  
T. Alafia Samuels ◽  
...  
Keyword(s):  
Dengue Virus ◽  
Dengue Fever ◽  
Small Sample Size ◽  
Health Planning ◽  
Case Fatality ◽  
Small Sample ◽  
Severe Dengue ◽  
Medical Attention ◽  
Enzyme Linked Immunosorbent Assay ◽  
Virus Serotype

Analysis of the temporal, seasonal and demographic distribution of dengue virus (DENV) infections in Barbados was conducted using national surveillance data from a total of 3994 confirmed dengue cases. Diagnosis was confirmed either by DENV–specific real time reverse transcriptase polymerase chain reaction (rRT–PCR), or non–structural protein 1 (NS1) antigen or enzyme linked immunosorbent assay (ELISA) tests; a case fatality rate of 0.4% (10/3994) was observed. The dengue fever (DF) prevalence varied from 27.5 to 453.9 cases per 100,000 population among febrile patients who sought medical attention annually. DF cases occurred throughout the year with low level of transmission observed during the dry season (December to June), then increased transmission during rainy season (July to November) peaking in October. Three major dengue epidemics occurred in Barbados during 2010, 2013 and possibly 2016 with an emerging three–year interval. DF prevalence among febrile patients who sought medical attention overall was highest among the 10–19 years old age group. The highest DF hospitalisation prevalence was observed in 2013. Multiple serotypes circulated during the study period and Dengue virus serotype 2 (DENV–2) was the most prevalent serotype during 2010, whilst DENV–1 was the most prevalent serotype in 2013. Two DENV–1 strains from the 2013 DENV epidemic were genetically more closely related to South East Asian strains, than Caribbean or South American strains, and represent the first ever sequencing of DENV strains in Barbados. However, the small sample size (n = 2) limits any meaningful conclusions. DF prevalence was not significantly different between females and males. Public health planning should consider DENV inter–epidemic periodicity, the current COVID–19 pandemic and similar clinical symptomology between DF and COVID–19. The implementation of routine sequencing of DENV strains to obtain critical data can aid in battling DENV epidemics in Barbados.

scholarly journals Serological evidence of association between Helicobacter pylori infection and coronary artery disease

2020 ◽  
Vol 21 (2) ◽  
pp. 88-96
Author(s):  
S.M. EL-Ageery ◽  
N.S. Gouda ◽  
I.M. Fawzy ◽  
A. Bahy-Eldeen ◽  
R. Mahmoud
Keyword(s):  
Coronary Artery Disease ◽  
Helicobacter Pylori ◽  
Coronary Artery ◽  
Density Lipoprotein ◽  
Enzyme Linked Immunosorbent Assay ◽  
Control Group ◽  
Serological Evidence ◽  
Autoimmune Reaction ◽  
Artery Disease ◽  
H Pylori

Background: Studies have reported relationship between chronic  Helicobacter pylori infection and coronary artery disease (CAD). The  cytotoxin-associated gene A product (CagA) is an immunodominant protein which indicates infection with virulent H. pylori strains. Significant  associations of CagA-positive H. pylori strains with coronary artery disorders have been widely reported. H. pylori is also known to produce different heat shock proteins (HSPs) which can stimulate the production of specific  antibody against microbial proteins and capable of eliciting autoimmune reaction against human tissue expressing HSPs such as vascular  endothelial cells. The objectives of this study are to investigate the  association between H. pylori and CagA with coronary atherosclerosis and CAD, and to determine the possible role of H. pylori HSP60 protein in increasing the risk of CAD development. Methods: This study included 70 patients with stable angina and 70 age and gender-matched controls. Each group was evaluated by clinical history, physical examination, cardiac echocardiography (ECHO) and electrocardiography (ECG) with and without exercise. Fasting blood glucose, total cholesterol (TC), low density lipoprotein (LDL), high density lipoprotein (HDL) and triglycerides (TG) were estimated by automated enzymatic methods. H. pylori IgG, CagA IgG and HSP60 IgG were measured by enzyme-linked immunosorbent assay (ELISA) for both groups. Results: The seroprevalence of H. pylori infection was high in both groups; 75.7% in case and 68.6% in control (p=0.346). Serum IgG levels were significantly higher for CagA (p=0.028) and HSP60 (p<0.001) in cases than in controls. There was significant association between H. pylori and CagA IgGs in cases (p=0.007) but no association in controls (p=0.700). Higher HSP60 IgG level was significantly associated with both positive H. pylori IgG (p<0.001) and CagA IgG (p<0.001) in cases but no significant association was found with H. pylori (p=0.815) or CagA (p=0.332) IgG levels in the control group. Serum values were significantly higher for TC (p<0.001), TG (p<0.001) and LDL (p=0.004) while value for HDL was significantly lower (p<0.001) in H. pylori IgG-positive subjects (case and control). Conclusion: There is serological evidence that H. pylori infection may pose a significant risk factor for CAD. Since H. pylori can be eliminated by specific treatment, this may be a good preventive approach for CAD.Key words: H. pylori, coronary artery disease, CagA, HSP60, serology.

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