scholarly journals DENGUE OUTBREAK IN MATO GROSSO STATE, MIDWESTERN BRAZIL

2015 ◽  
Vol 57 (6) ◽  
pp. 489-496 ◽  
Author(s):  
Letícia Borges da Silva HEINEN ◽  
Nayara ZUCHI ◽  
Belgath Fernandes CARDOSO ◽  
Marcelo Adriano Mendes dos SANTOS ◽  
Mauricio Lacerda NOGUEIRA ◽  
...  

Dengue virus (DENV) is the most frequent arbovirus worldwide. In this study, we report a large outbreak in Mato Grosso State (MT). Serum samples from 604 patients with acute febrile illness for less than five days were inoculated in C6/36 cells, then infected cells were subjected to an indirect immunofluorescence test for DENV serotypes and yellow fever virus. Serum samples were submitted to a multiplex-semi-nested-RT-PCR for 11 flaviviruses. DENV-4 was isolated in 150/604 (24.8%) and DENV-1 in 19/604 (3.1%) specimens. By RT-PCR, 331 (54.8%) samples tested positive for DENV; 321 had single infections (DENV-4 n = 305; DENV-1 n = 15; DENV-3 n = 1), nine had co-infections of DENV-1/DENV-4, and one of DENV-2/DENV-4. DENV-4 was detected in 315/331 (95.2%) positive patients from 17 municipalities, and DENV-1 in 24/331 (7.2%) patients from five cities in north-central MT and the city of Cuiaba. The incidence of infection was higher in patients aged 20-39 (142/331; 42.9%). The NS5 partial nucleotide sequence of DENV-1 was most similar to that of genotype V, DENV-2 to Southeast Asian/American, DENV-3 to genotype III, and DENV-4 to genotype II strains, considered the most frequent strains in Brazil. This outbreak coincided with the introduction of DENV-4 in the state. Cuiaba was hyperendemic for the four DENV serotypes, highlighting the necessity for arbovirus surveillance in MT.

2015 ◽  
Vol 57 (3) ◽  
pp. 215-220 ◽  
Author(s):  
Letícia Borges da Silva HEINEN ◽  
Nayara ZUCHI ◽  
Otacília Pereira SERRA ◽  
Belgath Fernandes CARDOSO ◽  
Breno Herman Ferreira GONDIM ◽  
...  

The dengue virus (DENV), which is frequently involved in large epidemics, and the yellow fever virus (YFV), which is responsible for sporadic sylvatic outbreaks, are considered the most important flaviviruses circulating in Brazil. Because of that, laboratorial diagnosis of acute undifferentiated febrile illness during epidemic periods is frequently directed towards these viruses, which may eventually hinder the detection of other circulating flaviviruses, including the Saint Louis encephalitis virus (SLEV), which is widely dispersed across the Americas. The aim of this study was to conduct a molecular investigation of 11 flaviviruses using 604 serum samples obtained from patients during a large dengue fever outbreak in the state of Mato Grosso (MT) between 2011 and 2012. Simultaneously, 3,433 female Culex spp. collected with Nasci aspirators in the city of Cuiabá, MT, in 2013, and allocated to 409 pools containing 1-10 mosquitoes, were also tested by multiplex semi-nested reverse transcription PCR for the same flaviviruses. SLEV was detected in three patients co-infected with DENV-4 from the cities of Cuiabá and Várzea Grande. One of them was a triple co-infection with DENV-1. None of them mentioned recent travel or access to sylvatic/rural regions, indicating that transmission might have occurred within the metropolitan area. Regarding mosquito samples, one pool containing one Culex quinquefasciatus female was positive for SLEV, with a minimum infection rate (MIR) of 0.29 per 1000 specimens of this species. Phylogenetic analysis indicates both human and mosquito SLEV cluster, with isolates from genotype V-A obtained from animals in the Amazon region, in the state of Pará. This is the first report of SLEV molecular identification in MT.


2014 ◽  
Vol 143 (2) ◽  
pp. 412-418 ◽  
Author(s):  
P. V. BARDE ◽  
B. K. KORI ◽  
M. K. SHUKLA ◽  
P. K. BHARTI ◽  
G. CHAND ◽  
...  

SUMMARYDengue is regarded as the most important arboviral disease. Although sporadic cases have been reported, serotypes responsible for outbreaks have not been identified from central India over the last 20 years. We investigated two outbreaks of febrile illness, in August and November 2012, from Korea district (Chhattisgarh) and Narsinghpur district (Madhya Pradesh), respectively. Fever and entomological surveys were conducted in the affected regions. Molecular and serological tests were conducted on collected serum samples. Dengue-specific amplicons were sequenced and phylogenetic analyses were performed. In Korea and Narsinghpur districts 37·3% and 59% of cases were positive, respectively, for dengue infection, with adults being the worst affected. RT–PCR confirmed dengue virus serotype 1 genotype III as the aetiology. Ninety-six percent of infections were primary. This is the first time that dengue virus 1 outbreaks have been documented from central India. Introduction of the virus into the population and a conducive mosquitogenic environment favouring increased vector density caused the outbreak. Timely diagnosis and strengthening vector control measures are essential to avoid future outbreaks.


Author(s):  
Natthaphon Nanakorn ◽  
Theerakamol Pengsakul ◽  
Kannika Bunrod ◽  
Suwich Thammapalo ◽  
Pathomporn Prikchoo ◽  
...  

Infection by the mosquito-borne chikungunya virus (CHIKV) causes acute febrile illness and debilitating arthralgia. Outbreaks are sometimes not recognized because of its clinical resemblance to the more common dengue fever ubiquitous in tropical countries. An upsurge of dengue-like illness was reported in Satun province located in southern Thailand during the rainy season in 2018. We investigated probable outbreak of CHIKV disease. We collected serum samples from 127 patients and tested for CHIKV infection based on nucleic acid and serological tests. CHIKV RNA amplified by real-time reverse-transcription polymerase chain reaction (RT-PCR) and IgM antibody against CHIKV were determined by immunochromatographic rapid test. Mosquitoes in the community were also trapped and tested for CHIKV. Conventional RT-PCR on initially positive samples was performed to obtain nucleotide sequences for subsequent phylogenetic analysis. In all, 39% (50/127) of the samples tested positive for CHIKV RNA, IgM, or both. Of these, CHIKV RNA was identified in 17% (21/127) of the samples. Fourteen percent (18/127) of the samples were simultaneously positive for both IgM and IgG, which suggest recent infection. One sample tested positive for both CHIKV IgM and RNA. Several samples from Aedes aegypti and Aedes albopictus mosquitoes were also CHIKV RNA-positive. Sequence analysis revealed that the Satun CHIKV belonged to the Indian Ocean lineage within the East/Central/South African (ECSA) clade with residues K211E and A226 in the E1 gene, and G205S and V264A in the E2 gene. The ECSA strain of CHIKV continues to evolve and possesses virulent potential despite causing prior outbreaks in the region.


2020 ◽  
Vol 9 (40) ◽  
pp. 2965-2969
Author(s):  
Suryamani Chintapalli ◽  
Apparao Peddepalli ◽  
Sivajyothi Pilli ◽  
Monika Deepthi Pilli ◽  
Kanaka Mahalakshmi Yandra

BACKGROUND Dengue is an acute febrile illness caused by mosquito-borne dengue viruses (DENV S) consisting of four serotypes (DENV 1 - 4) from flaviviridae family, genus flavivirus. These four are antigenically related serotypes designated as DEN V - 1, DEN V - 2, DEN V - 3 and DEN V – 4. In this context, the present study focuses on the circulating serotypes of dengue in coastal Andhra Pradesh. METHODS Study was done at Andhra Medical College, Visakhapatnam, teaching hospital in Andhra Pradesh. Acute phase dengue serum samples were collected and tested for NS1 antigen and antihuman IgM antibodies by enzyme linked –immunosorbent assay (ELISA). NS1 positive samples were further serotyped by reverse transcriptase real time polymerase chain reaction (R RT - PCR). RESULTS A total of 796 serum samples were included in the study. 300 (37.7 % ) samples were positive for NS1 and IgM antibodies. 192 NS1 antigen positive samples were further processed for serotyping by r RT PCR. Among these samples 72 were negative by r RT PCR. DENV-2 (41 %) was the predominant serotype followed by DENV-4 (37 %), DENV-3 (12 %) and DENV-1 (10 %) in the descending order. CONCLUSIONS All the four dengue serotypes are in co-circulation. Among all the four types, DENV-2 was predominant, followed by DENV-4. By knowing the predominant serotype in circulation, we can forecast dengue outbreaks and take necessary measures like control of vectors. KEY WORDS Andhra Pradesh, Dengue Virus, Dengue Virus - 2, Dengue Virus - 4, Outbreak, Serotypes


2021 ◽  
Vol 6 (3) ◽  
pp. 162
Author(s):  
Kanaporn Poltep ◽  
Juthamas Phadungsombat ◽  
Emi E. Nakayama ◽  
Nathamon Kosoltanapiwat ◽  
Borimas Hanboonkunupakarn ◽  
...  

Dengue is an arboviral disease highly endemic in Bangkok, Thailand. To characterize the current genetic diversity of dengue virus (DENV), we recruited patients with suspected DENV infection at the Hospital for Tropical Diseases, Bangkok, during 2018–2020. We determined complete nucleotide sequences of the DENV envelope region for 111 of 276 participant serum samples. All four DENV serotypes were detected, with the highest proportion being DENV-1. Although all DENV-1 sequences were genotype I, our DENV-1 sequences were divided into four distinct clades with different distributions in Asian countries. Two genotypes of DENV-2 were identified, Asian I and Cosmopolitan, which were further divided into two and three distinct clades, respectively. In DENV-3, in addition to the previously dominant genotype III, a cluster of 6 genotype I viruses only rarely reported in Thailand was also observed. All of the DENV-4 viruses belonged to genotype I, but they were separated into three distinct clades. These results indicated that all four serotypes of DENV with multiple genotypes and/or clades co-circulate in Bangkok. Continuous investigation of DENV is warranted to further determine the relationship between DENV within Thailand and neighboring countries in Southeast Asia and Asia.


Author(s):  
Aung Kyaw Kyaw ◽  
Mya Myat Ngwe Tun ◽  
Shine Thura Naing ◽  
Thida ◽  
Thein Thein Htwe ◽  
...  

AbstractBackgroundA school- and laboratory-based cross-sectional descriptive study was conducted to find out the burden of inapparent dengue virus (DENV) infection in Mandalay where DENV is endemic and there is circulation of all four DENV serotypes.MethodsA total of 420 students who had no history of fever and visited the hospital within 6 months were recruited from three monastic schools. Serum samples were collected and the DENV genome was checked by conventional one-step RT-PCR and anti-DENV IgM and IgG antibodies were determined. Inapparent dengue (DEN) infection is defined as individuals who were either RT-PCR-positive or anti-DENV IgM-positive with no clinical manifestations or mild symptoms, and which are not linked to a visit to a healthcare provider.ResultsAmong 420 students, 38 students (9.0%, 95% CI, 6.4 to 12.2) were confirmed as recent inapparent DEN infection. The DENV serotype-1 was detected in six students. Thirty-one out of 38 (81.6%) laboratory-confirmed inapparent DEN-infected students had primary infections and seven (18.4%) had secondary infections.ConclusionThis study explored the prevalence of inapparent DEN infection rate in urban monastic schools in Mandalay and showed that the rate of primary infection among inapparent DENV-infected children was high.


2021 ◽  
Vol 8 (1) ◽  
pp. 1042-1048
Author(s):  
Moushumi Ghosh Roy ◽  
Kutub Uddin ◽  
Din Islam ◽  
Anjuvan Singh ◽  
Mohammad Monirul Islam

Purposes: Dengue fever, a mosquito-borne viral disease, is a global public health burden affecting millions of people each year and over 40% of world populations are at risk of dengue. Therefore, prompt and accurate dengue diagnosis is inevitable for disease surveillance and for aiding disease management. In this study we report dengue virus (DENV) seroprevalence in Chittagong, Bangladesh along with clinical manifestation of dengue infections. Methods: All samples included in this study were selected based on dengue NS1-based diagnosis, clinical sign and symptoms were judged by expert clinical physicians and infecting DENV serotyping was done by RT-PCR. The blood cells (Platelet, Haematocrit, WBC etc) were analyzed using Haematology cell counter. Results: First, among the 112 DENV infected serum samples tested by RT-PCR, 42 were DENV positive where 76% samples had single DENV serotype infection and 24% were concurrently infected with two or more DENV serotypes, indicating that all four DENVs were present in a single dengue session in Chittagong, Bangladesh. Then, DENV4 was the most prevailed serotype, followed by DENV2, DENV1 and DENV3 in single DENV serotype infections. However, in almost 90% cases of concurrent multiple DENV infections DENV1 serotype was present. A detail analysis of clinical data clearly indicated that DENV1 and DENV2 resulted very similar patterns of clinical symptoms which were quite different from those caused by DENV3 and DENV4. For example, ache and pain were absent in DENV3 infection and diarrhea was absent in DENV4 infections. Furthermore, DENV3, both in single and concurrent multiple DENV infections, might increase dengue disease severity as observed highly reduced platelet counts along with increased WBC in patients infected with DENV3 serotype. Conclusion: All four DENV serotypes, both as single and concurrent multiple DENV infections, were present in single dengue session in Bangladesh. Despite having very similar sequences and structures all four DENVs might produce different disease spectra, ranging from classical dengue fever to dengue hemorrhagic fever. Concurrent multiple DENV infections could contribute increased dengue disease severity in dengue outbreaks in Bangladesh. Bioresearch Commu. 8(1): 1042-1048, 2022 (January)


Pathogens ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 166
Author(s):  
Saravana Murali Krishnan ◽  
Jayashri Mahalingam ◽  
Shanthi Sabarimurugan ◽  
Thiruvengadam Muthu ◽  
Baskar Venkidasamy ◽  
...  

Chikungunya (CHIKV) and Dengue (DENV) viruses cause an acute febrile illness which is hard to clinically differentiate and treat since both exhibit similar symptoms. Hence, this study was aimed at identifying the expression profiles of cytokines on co-infected samples and compare with CHIKV and DENV mono-infected samples. Serum samples of 292 suspected patients during 2009–2011 were analyzed. The presence of primary (IgM)/secondary (IgG) antibodies and early NS1 Dengue antigens were confirmed by capture ELISA. Molecular diagnosis and serotypes were discriminated by RT-PCR, confirmed by sequencing. All the plasma samples were assayed for cytokine expression by BDTM cytometry bead array (CBA) and compared with independent mono-infection viral load. Among the tested samples, 82 were confirmed as Dengue positive; 52 through IgM (17.8%), and 30 through IgG (10.2%). Additionally, 186 samples were confirmed as Chikungunya, 96 through IgM (32.6%) and 92 through IgG (31.5%) ELISA, respectively. Interestingly, 19 patients were co-infection positive in which, only 6 were confirmed for CHIKV and 7 for DENV by RT-PCR. Among 8 cytokines, IL-2, IL-8, IFNα, IFN γ, and IL-12 were found to be significantly different between co-infected and CHIKV mono-infected patients and correlated with viral load. DENV viral load was correlated with cytokine expression and a significant difference in IL-2 and IL-12 was observed between DENV mono-infected and DENV and CHIKV co-infected patients. Results indicated that apart from serological and molecular confirmation, cytokines could be used as a specific biomarker for the diagnosis of DENV and CHIKV. In the future, the role of independent cytokines can be determined to understand the pathogenesis and etiology of these dreadful diseases.


2019 ◽  
Vol 5 (Supplement_1) ◽  
Author(s):  
Mesfin Mengesha Tsegaye ◽  
Aadamu Tayachew ◽  
Desalegn Belay ◽  
Abebe Alemu ◽  
Berhane Beyene

Abstract Chikungunya is a viral disease (genus Alphavirus) which is transmitted to humans by infected mosquitoes—including Aedes aegypti and A. albopictus. An outbreak of febrile illness, suspected to have been caused by chikungunya, was reported in June 2016 from Dolloado district, Suuf Kebele, in the Somalia regional state of Ethiopia that borders the Mandera county of Kenya where a confirmed chikungunya outbreak was ongoing. Laboratory investigation was carried out to confirm if the outbreak in Ethiopia was caused by Chikungunya virus. Ten serum samples were collected from suspected patients visiting a health center in Suuf Kebel, who were then sent to the Nation laboratory in Ethiopian Public Health Institute. RNA was extracted from the serum samples using QIAgene RNA Mini kit, and PCR detection of dengue, chikungunya, and Zika virus nucleic acid was done using Trioplex Real-time RT-PCR Assay following the protocol from the Center for Disease Control (CDC). The Trioplex Real-time RT-PCR assay, for detection and differentiation of RNA from dengue, Chikungunya and Zika, was provided by CDC as part of the zika emergency preparedness effort. Of the nine samples tested, eight (88.88%) were found to be positive for chikungunya virus nucleic acid but negative for dengue and Zika virus nucleic acids. The median age of the affected sampled patients was 40 years, and males appear to be more affected (66.6% of sampled patients). The laboratory investigation confirmed that the outbreak was caused by chikungunya virus. Even though further molecular characterization of the positive isolates will provide more information as to the circulating genotypes and elucidate the origin of the outbreak virus, it is also possible to assume that the outbreak was an extension of the outbreak in neighboring countries in Kenya and, therefore, warrants that cross-border integration efforts to control chikungunya should be implemented by the concerned countries.


2020 ◽  
pp. 175717742097679
Author(s):  
Kordo Saeed ◽  
Emanuela Pelosi ◽  
Nitin Mahobia ◽  
Nicola White ◽  
Christopher Labdon ◽  
...  

Background: We report an outbreak of SARS coronavirus-2 (SARS-CoV-2) infection among healthcare workers (HCW) in an NHS elective healthcare facility. Methodology: A narrative chronological account of events after declaring an outbreak of SARS-CoV-2 among HCWs. As part of the investigations, HCWs were offered testing during the outbreak. These were: (1) screening by real-time reverse transcriptase polymerase chain reaction (RT- PCR) to detect a current infection; and (2) serum samples to determine seroprevalence. Results: Over 180 HCWs were tested by real-time RT-PCR for SARS-CoV-2 infection. The rate of infection was 15.2% (23.7% for clinical or directly patient-facing HCWs vs. 4.8% in non-clinical non-patient-facing HCWs). Of the infected HCWs, 57% were asymptomatic. Seroprevalence (SARS-CoV-2 IgG) among HCWs was 13%. It was challenging to establish an exact source for the outbreak. The importance of education, training, social distancing and infection prevention practices were emphasised. Additionally, avoidance of unnecessary transfer of patients and minimising cross-site working for staff and early escalation were highlighted. Establishing mass and regular screening for HCWs are also crucial to enabling the best care for patients while maintaining the wellbeing of staff. Conclusion: To our knowledge, this is the first UK outbreak report among HCWs and we hope to have highlighted some key issues and learnings that can be considered by other NHS staff and HCWs globally when dealing with such a task in future.


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