Serological evidence of exposure to Rift Valley, Dengue and Chikungunya Viruses among agropastoral communities in Manyara and Morogoro regions in Tanzania: A community Survey (original) (raw)

Seroprevalence of Infections with Dengue, Rift Valley Fever and Chikungunya Viruses in Kenya, 2007

PLOS ONE, 2015

Arthropod-borne viruses are a major constituent of emerging infectious diseases worldwide, but limited data are available on the prevalence, distribution, and risk factors for transmission in Kenya and East Africa. In this study, we used 1,091 HIV-negative blood specimens from the 2007 Kenya AIDS Indicator Survey (KAIS 2007) to test for the presence of IgG antibodies to dengue virus (DENV), chikungunya virus (CHIKV) and Rift Valley fever virus (RVFV).The KAIS 2007 was a national population-based survey conducted by the Government of Kenya to provide comprehensive information needed to address the HIV/AIDS epidemic. Antibody testing for arboviruses was performed on stored blood specimens from KAIS 2007 through a two-step sandwich IgG ELISA using either commercially available kits or CDC-developed assays. Out of the 1,091 samples tested, 210 (19.2%) were positive for IgG antibodies against at least one of the three arboviruses. DENV was the most common of the three viruses tested (12.5% positive), followed by RVFV and CHIKV (4.5% and 0.97%, respectively). For DENV and RVFV, the participant's province of residence was significantly associated (P.01) with seropositivity. Seroprevalence of DENV and RVFV increased with age, while there was no correlation between province of residence/age and seropositivity for CHIKV. Females had twelve times higher odds of exposure to CHIK as opposed to DENV and RVFV where both males and females had the same odds of exposure. Lack of education was significantly associated with a higher odds of previous infection with either DENV or RVFV (p <0.01). These data show that a number of people are at risk of arbovirus infections depending on their geographic location in Kenya and transmission of these pathogens is greater than previously appreciated. This poses a public health risk, especially for DENV.

Evidence of Chikungunya but not Dengue Virus Circulating among Febrile Patients during Low Transmission Period in Morogoro Municipality, Tanzania

International Journal of TROPICAL DISEASE & Health, 2020

Background: There is currently sufficient evidence available indicating that dengue and chikungunya viruses could be among the causes of fever in Tanzania. Overlapping clinical manifestations of chikungunya and dengue with other vector-borne parasitic diseases pose a challenge for medical diagnosis in Tanzania. A virus surveillance study was conducted in Morogoro Municipality which had no reports of outbreaks during high risk of transmission with dengue epidemics in the neighbouring Dar es Salaam. Methodology: The present study was carried out to screen for dengue (DENV) and chikungunya (CHIKV) in sera from patients with fever and malaria-like symptoms on selected health centres in Morogoro municipality (n = 5) during March-May 2018. Three hundred and twelve febrile individuals presenting to the outpatient department were screened for the presence of chikungunya and dengue viruses using Multiplex real-time reverse transcription-polymerase chain reaction. Results: Acute CHIKV infecti...

Seroprevalence of Antibodies against Chikungunya, Dengue, and Rift Valley Fever Viruses after Febrile Illness Outbreak, Madagascar

Emerging Infectious Diseases, 2012

, two-3 months after an outbreak of a febrile disease with joint pain on the eastern coast of Madagascar, we assessed serologic markers for chikungunya virus (CHIKV), dengue virus (DENV), and Rift Valley fever virus (RVFV) in 1,244 pregnant women at 6 locations. In 2 eastern coast towns, IgG seroprevalence against CHIKV was 45% and 23%; IgM seroprevalence was 28% and 5%. IgG seroprevalence against DENV was 17% and 11%. No anti-DENV IgM was detected. At 4 locations, 450-1,300 m high, IgG seroprevalence against CHIKV was 0%-3%, suggesting CHIKV had not spread to higher inlandaltitudes. Four women had IgG against RVFV, probably antibodies from a 2008 epidemic. Most (78%) women from coastal locations with CHIKV-specifi c IgG reported joint pain and stiffness; 21% reported no symptoms. CHIKV infection was signifi cantly associated with high bodyweight. The outbreak was an isolated CHIKV epidemic without relevant DENV co-transmission.

Occurrence of 4 Dengue Virus Serotypes and Chikungunya Virus in Kilombero Valley, Tanzania, During the Dengue Outbreak in 2018

Open Forum Infectious Diseases, 2020

Background Dengue and Chikungunya viruses can cause large-scale epidemics, with attack rates of up to 80%. In Tanzania, there have been repeated outbreaks of dengue fever, the most recent in 2018 and 2019, mostly affecting the coastal areas. Despite the importance of these viruses, there is limited knowledge on the epidemiology of dengue (DENV) and Chikungunya (CHIKV) in Tanzania. This study was conducted to investigate the prevalence of DENV and CHIKV in Kilombero Valley, Tanzania. Methods A cross-sectional study was conducted at Kibaoni Health Center in Kilombero Valley, Southeastern Tanzania, in the rainy and dry seasons of 2018. Febrile patients of any age and gender were enrolled from the outpatient department. Blood samples were taken and screened for DENV and CHIKV viral RNA by real-time reverse transcription polymerase chain reaction assays. Results Overall, 294 patients were recruited. Most were females (65%), and one-third of patients were aged 14–25 years. DENV and CHIKV ...

Evidence for chikungunya and dengue transmission in Quelimane, Mozambique: Results from an investigation of a potential outbreak of chikungunya virus

PloS one, 2018

In January 2016, health authorities from Zambézia province, Mozambique reported the detection of some patients presenting with fever, arthralgia, and a positive result for chikungunya in an IgM-based Rapid Diagnostic Test (RDT). We initiated a study to investigate a potential chikungunya outbreak in the city of Quelimane. From February to June 2016, we conducted a cross-sectional study enrolling febrile patients attending five outpatient health units in Quelimane. Serum from each patient was tested for CHIKV and DENV, using IgM and IgG ELISA and qRT-PCR. Patients were also tested for malaria by RDT. Entomological surveys were performed around patients' households, and we calculated the proportion of positive ovitraps and the egg density per trap. A total of 163 patients were recruited, of which 99 (60.7%) were female. The median age was 28 years. IgM and IgG anti-CHIKV antibodies were identified in 17 (10.4%) and 103 (63.2%) patients, respectively. Plaque reduction neutralizatio...

Prevalence of dengue and chikungunya virus infections in north-eastern Tanzania: a cross sectional study among participants presenting with malaria-like symptoms

BMC Infectious Diseases, 2016

Background: In spite of increasing reports of dengue and chikungunya activity in Tanzania, limited research has been done to document the general epidemiology of dengue and chikungunya in the country. This study aimed at determining the sero-prevalence and prevalence of acute infections of dengue and chikungunya virus among participants presenting with malaria-like symptoms (fever, headache, rash, vomit, and joint pain) in three communities with distinct ecologies of northeastern Tanzania. Methods: Cross sectional studies were conducted among 1100 participants (aged 2-70 years) presenting with malaria-like symptoms at health facilities at Bondo dispensary (Bondo, Tanga), Hai hospital (Hai, Kilimanjaro) and TPC hospital (Lower Moshi). Participants who were malaria negative using rapid diagnostic tests (mRDT) were screened for sero-positivity towards dengue and chikungunya Immunoglobulin G and M (IgG and IgM) using ELISA-based kits. Participants with specific symptoms defined as probable dengue and/or chikungunya by WHO (fever and various combinations of symptoms such as headache, rash, nausea/vomit, and joint pain) were further screened for acute dengue and chikungunya infections by PCR. Results: Out of a total of 1100 participants recruited, 91.2 % (n = 1003) were malaria negative by mRDT. Out of these, few of the participants (<5 %) were dengue IgM or IgG positive. A total of 381 participants had fever out of which 8.7 % (33/381) met the defined criteria for probable dengue, though none (0 %) was confirmed to be acute cases. Chikungunya IgM positives among febrile participants were 12.9 % (49/381) while IgG positives were at 3.7 % (14/381). A total of 74.2 % (283/381) participants met the defined criteria for probable chikungunya and 4.2 % (11/263) were confirmed by PCR to be acute chikungunya cases. Further analyses revealed that headache and joint pain were significantly associated with chikungunya IgM seropositivity. Conclusion: In northeastern Tanzania, mainly chikungunya virus appears to be actively circulating in the population. Continuous surveillance is needed to determine the contribution of viral infections of fever cases. A possible establishment of arboviral vector preventive control measures and better diagnosis of pathogens to avoid over-treatment of other diseases should be considered.

Chikungunya, Dengue and West Nile Virus Infections in Northern Tanzania

Journal of Advances in Medicine and Medical Research

Aim: We aimed at determine the prevalence of Chikungunya virus (CHIKV), Dengue virus (DENV) and West Nile virus (WNV) in Bondo and Magugu wards in Handeni and Babati districts in Northern Tanzania, in a cross sectional analytical study. Study Design: This was cross sectional, community based study involving individuals aged 1-80 years of age. Reverse transcription Polymerase Chain Reaction (RT-PCR) was used to detect arboviruses in whole blood samples. Data was analyzed using SPSS 22.0. Chi square and logistic regression analyses were used to determine associations of explanatory factors and arbovirus infection. Results: Out of 128 participants recruited, 10 (7.8%) and 1 (0.8 %) were positive for CHIKV and DENV, respectively. None of the participants recruited was positive for WNV. Most cases of arboviruses were detected in Magugu with 8 (12.31%) and 1 (1.54%) individuals being positive for CHIKV and DENV respectively. Male sex was associated with CHIKV infection (χ2=9.126,

Seroprevalence of chikungunya virus (CHIKV) infection on Lamu Island, Kenya, October 2004

The American journal of …, 2008

An outbreak of Chikungunya virus (CHIKV) disease associated with high fever and severe protracted arthralgias was detected in Lamu, Kenya, peaking in July 2004. At least 1,300 cases were documented. We conducted a seroprevalence study to define the magnitude of transmission on Lamu Island. We conducted a systematic crosssectional survey. We administered questionnaires and tested 288 sera from Lamu residents for IgM and IgG antibodies to CHIKV. Chikungunya virus infection (seropositivity) was defined as a person with IgG and/or IgM antibodies to CHIKV. IgM antibodies to CHIKV were detected in 18% (53/288) and IgG antibodies in 72% (206/288); IgM and/or IgG antibodies were present in 75% (215/288). The seroprevalence findings suggested that the outbreak was widespread, affecting 75% of the Lamu population; extrapolating the findings to the entire population, 13,500 (95% CI, 12,458-14328) were affected. Vector control strategies are needed to control the spread of this mosquito-borne infection.

Seroprevalence of Chikungunya Virus in a Rural Community in Brazil

PLoS neglected tropical diseases, 2017

The emergence of the Chikungunya virus (CHIKV) is currently expanding. In 2015, 38,332 cases of Chikungunya were reported to the Brazilian epidemiological surveillance system. Eighteen months after notification of the first case in the city of Feira de Santana, we conducted the first serosurvey to define the magnitude of transmission in a rural community in Brazil. The serosurvey was conducted in a random sample of 450 residences in the Chapada district, located 100 kilometers from Feira de Santana. We administered questionnaires and tested 120 sera from Chapada district residents for CHIKV IgM- and IgG-specific antibodies. An individual with CHIKV infection was defined as any person with CHIKV IgM or IgG antibodies detected in the serum. One Hundred cases of Chikungunya were reported after prolonged rainfall, which reinforced the relationship between the rainfall index and CHIKV transmission. Eighteen months after the start of the outbreak, we identified a seroprevalence of 20% (95...