Is dengue and malaria co-infection more severe than single infections? A retrospective matched-pair study in French Guiana

Worldwide distribution, symptoms and diagnosis of the coinfections between malaria and arboviral diseases: a systematic review

The coinfection between malaria (ML) and arboviral diseases represents a major global public health problem, particularly in tropical and subtropical countries. Despite its relevance, this topic is still insufficiently discussed in the current literature. Here, we aimed to investigate the worldwide distribution, symptoms, and diagnosis during coinfection between ML and arboviral diseases. We conducted a systematic review following the Preferred reporting items for systematic reviews and meta-analyses (PRISMA) statement and assessed the selection and eligibility criteria, created and diagrammed maps, and analysed major symptoms with 95% confidence intervals (CI) using prevalence ratio and effect size, also performing latent class analysis. A total of 85,485 studies were retrieved, of which 56 were included: 57.14% in Asia, 25% in Africa, 14.30% in South America, and 3.56% in Europe. A total of 746 individuals were reported to be coinfected with Plasmodium and arbovirus. Concurrent ML, Dengue (DEN), Chikungunya (CHIK), and Zika (ZIK) patients are more likely to present headache and skin rash. Regarding diagnosis, 58,253 were made, of which 38,176 were positive (ML and at least one arboviral disease). The magnitude of these pathogens' coexistence points out the pressing need for improvements in public health policies towards diagnosis and prevention of both diseases, especially in endemic areas.

Severe coinfection of dengue and malaria: A case report

Key Clinical Message

In countries like Sudan, where several infectious diseases are prevalent, health care providers should not be satisfied with initial detection of a single pathogen and whenever it is feasible, they should investigate coinfections. Infections with high mortality or severe morbidity should be prioritized during the differential diagnosis particularly for diseases with similar clinical manifestations to reduce the death and disability rates. However, this requires substantial improvement in the diagnostic capacity.

Abstract

Here we report a case of dengue and malaria coinfection from the southeast region of Sudan, bordering Ethiopia and Eritrea. A 25-year-old male from Sudan presented with symptoms of fever, chills, vomiting, and muscle and joint pain. Laboratory investigations confirmed a coinfection of dengue and malaria, which is assumingly not uncommon in areas heavily syndemic with several diseases but it is severely under-detected, underreported, and underestimated. The case has fully recovered after the supportive care for dengue and chemotherapy treatment for malaria. In such a case, it was important to monitor the patient's recovery and the treatment outcome through clinical indicators and laboratory parameters to update the treatment course whenever needed, according to response. The increasing burden and outbreaks of vector-borne diseases including dengue and malaria in Sudan, indicates the need for improving the implementation of the global vector control response that established by the World Health Organization. Additionally, the increasing prevalent of coinfections is urging substantial improvement in the diagnostic capacity in endemic countries.

Clinical description of dengue and chikungunya virus infections amongst acute febrile patients in a malaria endemic area of Mfou, the Centre region of Cameroon

This study aims to determine the frequency and clinical manifestations of dengue and chikungunya viral infections in the district hospital of Mfou, Centre region of Cameroon where malaria is endemic. Blood samples were collected from suspected cases and tested for Plasmodium parasites and for the molecular detection of viral RNAs (dengue, zika and chikungunya viruses) using TRIOPLEX qPCR. A total of 108 patients were clinically suspected among which 25 % were male and 50 % were less than 15.5 years old. Of these 14.8 % (16/108) and 2.8 % (3/108) had acute dengue and chikungunya fevers respectively. Co-infection with malaria was reported in 56.3 % (9/16) of Dengue cases and 33.3 % (1/3) of chikungunya cases. Clinical profiling further revealed that nausea and vomiting show a significant difference in dengue infected individuals to those of non-infected individuals (P = 0.027). The presence of dengue fever and chikungunya fever and the absence of specific clinical manifestations highlight the need to strengthen surveillance of acute febrile infections for a better estimation of the burden of arboviruses.

Concurrent infection of dengue virus with malaria parasites among outpatients attending healthcare facilities in Benin city, Nigeria

Background

Dengue virus (DENV) and malaria parasites (MP) are among the common febrile diseases affecting the tropics and subtropics of the world. Both are mosquito-borne pathogens affecting humans and other animals.

Methods

Blood samples were collected from 280 consented out-patients attending the selected hospitals and were analyzed. Malaria parasites were detected using microscopy and Malaria Ag Pf/Pan Rapid Test Device. Dengue virus was detected by serology and heminested reverse transcriptase PCR (hnRT-PCR) to target the flavivirus polymerase (NS5) gene.

Results

Malaria parasites recorded a total positivity of 151 patients (53.9%) using microscopy, while DENV antibodies (DENV IgM and DENV IgG) were positive in 16 (5.7%) and 39 (13.9%) patients, respectively. There was a concurrent infection between MP/DENV IgM in 13 (4.6%) patients and MP/DENV IgG in 27 (9.6%) patients. Molecular identification revealed DENV serotype 2 in circulation.

Conclusion

This study documents molecular evidence of dengue virus coexisting with malaria parasites in the study population, hence the need for efficient surveillance and control system.

Codetection of Plasmodium falciparum in Children Hospitalized With Dengue Fever in the Dominican Republic

BACKGROUND

Cases of malaria and dengue in the Dominican Republic both spiked in 2019, but their rates of codetection are poorly characterized, especially in children.

METHODS

We performed a prospective, observational study in January to December 2019 at the Hospital Infantil Robert Reid Cabral, in the Dominican Republic, enrolling hospitalized children with a clinical suspicion of dengue fever. Participants with a positive plasma dengue IgM antibodies were included in this study. Clinical and hospital data were abstracted, and dried blood spot samples were collected from participants and tested with quantitative polymerase chain reaction to detect the presence of Plasmodium falciparum DNA.

RESULTS

A total of 429 children with serological evidence of acute dengue were included in this study, of whom 1.4% (n = 6/429) had codetection of dengue and malaria. There were no significant differences in fever duration or presence of vomiting, abdominal pain and rash between both groups. Children with dengue and malaria codetection were numerically more often admitted to the pediatric intensive care unit, despite no differences found in overall clinical severity.

CONCLUSIONS

The codetection of malaria and dengue in children was overall uncommon in our Dominican Republic cohort despite the rise in cases in 2019 but may be associated with a more severe hospital course. Further epidemiological and cohort studies to characterize the risk of both pathogens as case numbers fluctuate will be important to better understand the dynamics of coinfections.

Increasing prevalence of malaria and acute dengue virus coinfection in Africa: a meta-analysis and meta-regression of cross-sectional studies

BACKGROUND

Malaria and dengue fever are the leading causes of acute, undifferentiated febrile illness. In Africa, misdiagnosis of dengue fever as malaria is a common scenario. Through a systematic review of the published literature, this study seeks to estimate the prevalence of dengue and malaria coinfection among acute undifferentiated febrile diseases in Africa.

METHODS

Relevant publications were systematically searched in the PubMed, Cochrane Library, and Google Scholar until May 19, 2023. A random-effects meta-analysis and meta-regression were used to summarize and examine the prevalence estimates.

RESULTS

Twenty-two studies with 22,803 acute undifferentiated febrile patients from 10 countries in Africa were included. The meta-analysis findings revealed a pooled prevalence of malaria and dengue coinfection of 4.2%, with Central Africa having the highest rate (4.7%), followed by East Africa (2.7%) and West Africa (1.6%). Continent-wide, Plasmodium falciparum and acute dengue virus coinfection prevalence increased significantly from 0.9% during 2008-2013 to 3.8% during 2014-2017 and to 5.5% during 2018-2021 (p = 0.0414).

CONCLUSION

There was a high and increasing prevalence of malaria and acute dengue virus coinfection in Africa. Healthcare workers should bear in mind the possibility of dengue infection as a differential diagnosis for acute febrile illness, as well as the possibility of coexisting malaria and dengue in endemic areas. In addition, high-quality multicentre studies are required to verify the above conclusions. Protocol registration number: CRD42022311301.

Prevalence of malaria and dengue co-infections among febrile patients during dengue transmission season in Kassala, eastern Sudan

BACKGROUND

Malaria and dengue are common mosquito-borne diseases around the world that cause high mortality and morbidity. The number of cases of both diseases is currently rising in Sudan and is associated with climate and environmental changes. Limited information is available on malaria and dengue co-infections and the severity of the two diseases among febrile patients in eastern Sudan. Thus, this study aimed to estimate the prevalence of malaria and dengue co-infections among febrile patients in Kassala, eastern Sudan.

METHODOLOGY/PRINCIPAL FINDINGS

A cross-sectional hospital-based study was conducted among febrile patients from September to December 2019. A total of 395 patients were enrolled after consenting to participate in the study. Demographic and clinical data were collected by structured questionnaires. Blood samples were provided to diagnose malaria infections using microscopy and polymerase chain reaction (PCR) and for serology diagnosis of dengue using enzyme-linked immune sorbent assay (ELISA) IgM. Multiple logistic regression analysis was used to assess the association between demographic information, clinical symptoms and malaria and dengue co-infections. Out of 395 febrile patients examined 158 (40%) were malaria positive and 67 (17%) were dengue positive. The prevalence of malaria and dengue co-infections was 6.6% (26/395). Results of multiple logistic regression indicated that elder patients (41-60 years) had less rate of co-infections (OR = 0.3, 95% CI 0.11 to 0.81, p-value = 0.018), while patients of co-infections were eight times more likely to have fatigue, and two times more likely to suffer from joint and muscle pain and this difference was statistically significant with (OR = 8.3, 95% CI: 1.89 to 37.22, p-value = 0.005) and (OR = 2.4, 95% CI 1.10 to 5.39, p-value = 0.027), respectively.

CONCLUSIONS/SIGNIFICANCE

This study confirmed the existence of malaria and dengue co-infections among febrile patients in Kassala, eastern Sudan for the first time. The severity of clinical symptoms of patients with malaria and dengue co-infections was observed, and the co-infections were found prevalent among young people.

Seroprevalence of viral and bacterial pathogens among malaria patients in an endemic area of southern Venezuela

BACKGROUND

Malaria remains a leading public health problem worldwide. Co-infections with other pathogens complicate its diagnosis and may modify the disease's clinical course and management. Similarities in malaria clinical presentation with other infections and overlapping endemicity result in underdiagnosis of co-infections and increased mortality. Thus, the aim of this study was to determine the seroprevalence of viral and bacterial pathogens among diagnosed malaria patients in malaria-endemic areas in Venezuela.

METHODS

A cross-sectional study was conducted on malaria patients attending three reference medical centres in Ciudad Bolivar, Venezuela. Clinical evaluation and laboratory tests for dengue virus (DENV), chikungunya virus (CHIKV), viral hepatitis [hepatitis A virus (HAV), hepatitis B virus (HBV), and hepatitis C virus (HCV)], and leptospirosis (LEP) were performed by enzyme-linked immunosorbent assays. Previous exposure to these pathogens was defined by the presence of specific immunoglobulin (Ig) G, and co-infection or recent exposure (CoRE) was determined by the presence of specific IgM alone or IgM + IgG. Data analysis considered descriptive statistics. Parameter distribution was statistically evaluated using Kolmogorov-Smirnov test and the necessary comparison tests. Odds ratio (OR) for complications was determined according to CoRE presence with a 95% confidence interval (CI).

RESULTS

A total of 161 malaria patients were studied, 66% infected with Plasmodium vivax, 27% with P. falciparum, and 7.5% harboured P. vivax/P. falciparum mixed infection. Previous exposure to DENV (60%) and CHIKV (25%) was frequent. CoRE was confirmed in 55 of the 161 malaria patients (34%) and were more frequent in P. falciparum (49%) than in P. vivax (29%) and mixed malaria patients (25%) (OR = 2.43, 95% CI: 1.39-4.25, P = 0.018). The most frequent CoRE was DENV (15%), followed by HAV (12%), HBV (6.2%), CHIKV (5.5%), and LEP (3.7%); HCV CoRE was absent. Complicated malaria was significantly more frequent in patients with CoRE (56%) than those without CoRE (36%; OR = 2.31, 95% CI: 1.18-4.92, P = 0.013).

CONCLUSIONS

We found high CoRE prevalence in malaria patients as determined by serology in the study region; cases were associated with a worse clinical outcome. Further prospective studies with samples from different infection sites and the use of molecular tools are needed to determine the clinical significance of these findings.

Cross-reactivity of SARS-CoV-2 with other pathogens, especially dengue virus: A historical perspective

Dengue is a vector-borne viral disease caused by a Flavivirus whereas the COVID-19 pandemic was caused by a highly contagious virus, SARS-CoV-2 belonging to the family Coronaviridae. However, COVID-19 severity was observably less in dengue-endemic countries and vice versa especially during the active years of the pandemic (2019-2021). We observed that dengue virus (DENV) antibodies (Abs) could cross-react with SARS-CoV-2 spike antigen. This resulted in SARS-CoV-2 false positivity by rapid Ab test kits. DENV Abs binding to SARS-CoV-2 receptor-binding domain (and the reverse scenario), as revealed by docking studies further validated DENV and SARS-CoV-2 cross-reactivity. Finally, SARS-CoV-2 Abs were found to cross-neutralize DENV1 and DENV2 in virus neutralization test (VNT). Abs to other pathogens like Plasmodium were also cross-reactive but non-neutralizing for SARS-CoV-2. Here, we analyze the existing data on SARS-CoV-2 cross-reactivity with other pathogens, especially dengue to assess its impact on health (cross-protection?) and differential sero-diagnosis/surveillance.

Fluid management in children with severe dengue: a narrative review

Dengue is a mosquito-borne arboviral infection of increasing public health importance. Globally, children account for a significant proportion of infections. No pathogen-specific treatment currently exists, and the current approach to reducing disease burden is focused on preventative strategies such as vector control, epidemiological interventions, and vaccination in selected populations. Once infected, the mainstay of treatment is supportive, of which appropriate fluid management is a cornerstone. The timely provision of fluid boluses has historically been central to the management of septic shock. However, in patients with dengue shock, particular emphasis is placed on judicious fluid administration. Certain colloids such as hydroxyethyl starches and dextran, despite no longer being used routinely in intensive care units due to concerns of acute kidney injury and impairment of coagulation, are still commonly used in dengue shock syndrome. Current guidelines recommend initial crystalloid therapy, with consideration of colloids for severe or recalcitrant shock in patients with dengue. In this review, we discuss the pathophysiology of septic shock, and consider whether any differences in dengue exist that may warrant a separate approach to fluid therapy. We critically review the available evidence for fluid management in dengue, including the role of colloids. In dengue, there is increasing recognition of the importance of tailoring fluid therapy to phases of disease, with attention to the need for fluid "deresuscitation" once the critical phase of vascular leak passes.

Uncovering the Burden of Dengue in Africa: Considerations on Magnitude, Misdiagnosis, and Ancestry

Dengue is a re-emerging neglected disease of major public health importance. This review highlights important considerations for dengue disease in Africa, including epidemiology and underestimation of disease burden in African countries, issues with malaria misdiagnosis and co-infections, and potential evidence of genetic protection from severe dengue disease in populations of African descent. The findings indicate that dengue virus prevalence in African countries and populations may be more widespread than reported data suggests, and that the Aedes mosquito vectors appear to be increasing in dissemination and number. Changes in climate, population, and plastic pollution are expected to worsen the dengue situation in Africa. Dengue misdiagnosis is also a problem in Africa, especially due to the typical non-specific clinical presentation of dengue leading to misdiagnosis as malaria. Finally, research suggests that a protective genetic component against severe dengue exists in African descent populations, but further studies should be conducted to strengthen this association in various populations, taking into consideration socioeconomic factors that may contribute to these findings. The main takeaway is that Africa should not be overlooked when it comes to dengue, and more attention and resources should be devoted to this disease in Africa.

Management of dengue with co-infections: an updated narrative review

Dengue is a life-threatening mosquito borne viral disease. We are still in the era of supportive treatment where morbidity and mortality are a major concern. Dengue infection in presence of other co-infections makes this scenario rather worse. Timely recognition and raising alarm to be intensive is the need of the hour for primary care physicians practicing in the community and indoors. This review provides a comprehensive knowledge about the recent trends of coinfection in dengue as well as their management consideration which will be particularly helpful for physicians practicing in rural and remote areas of India.

Malaria and dengue in Hodeidah city, Yemen: High proportion of febrile outpatients with dengue or malaria, but low proportion co-infected

Background

The emergence of dengue in malaria-endemic countries with limited diagnostic resources, such as Yemen, can be problematic because presumptive treatment of febrile cases as being malaria is a common practice. Co-infections with dengue and malaria are often overlooked and misdiagnosed as being a mono-infection because of clinical similarities. In Hodeidah city, Yemen, the capacity to conduct the diagnosis can be aggravated by the war context. To assess the magnitude of the problem, we determined the proportions of malaria, dengue and co-infection in relation to clinical characteristics among febrile outpatients.

Methods

This cross-sectional study included 355 febrile outpatients from Hodeidah city during the malaria transmission season (September 2018 –February 2019). Sociodemographic and clinical characteristics were collected using a pre-designed, structured questionnaire. Malaria was confirmed using microscopy and rapid diagnostic tests (RDTs), while dengue was confirmed using RDTs.

Results

Mono-infection proportions of 32.4% for falciparum malaria and 35.2% for dengue were found, where about two-thirds of dengue patients had a recent probable infection. However, co-infection with falciparum malaria and dengue was detected among 4.8% of cases. There was no statistically significant difference between having co-infection and mono-infection with malaria or dengue in relation to the sociodemographic characteristics. On the other hand, the odds of co-infection were significantly lower than the odds of malaria among patients presenting with sweating (OR = 0.1, 95% CI: 0.05–0.45; p <0.001), while the odds of co-infection were 3.5 times significantly higher than the odds of dengue among patients presenting with vomiting (OR = 3.5, 95% CI: 1.20–10.04; p <0.021). However, there were no statistically significant differences between having co-infection and mono-infection (malaria or dengue) in relation to other clinical characteristics.

Conclusions

Mono-infection with malaria or dengue can be detected among about one-third of febrile outpatients in Hodeidah, while almost 5.0% of cases can be co-infected. Sociodemographic and clinical characteristics cannot easily distinguish malaria patients from dengue-infected or co-infected ones, reinforcing the necessity of laboratory confirmation and avoidance of treating febrile patients as being presumed malaria cases.

Investigation of dengue-malaria coinfection among febrile patients consulting at Ngaoundere Regional Hospital, Cameroon

This study aimed at evaluating the seroprevalence of dengue among malarious patients consulting at the Ngaoundere Regional Hospital. During 2 months and a half, 174 participants were recruited and their blood samples were screened for Plasmodium spp and then for Dengue virus (DENV) infection using rapid diagnostic tests. Also, hematological asparameters were measured using a hematology autoanalyzer. Among patients tested, 134 (77.01%) were malaria-positive, and 12/134 (8.95%) were coinfected. In this population, 8/12 (66.67%) were only anti-DENV IgM-positive, 3/12 (25%) were both NS1 and anti-DENV IgM positive, and 1/12 (8.33%) were anti-DENV IgG-positive. Furthermore, women were more affected (58.3%) than men (41.7%). The most affected age groups were young people aged less than or equal to 15 years (33.3%) and adults aged between 30 and 45 years (33.3%). A significant association (p < .05; odds ratio [OR] = 5.16) was found between the age range (30-45) and dengue-malaria coinfection. Similarly, we noted a significant association between the coinfection, and joint pain (p < .05; OR = 6.15), fatigue (p < .01; OR = 5.74), and chills (p < .05; OR = 0). Analysis of hematologic parameters showed a significant decrease (p < .001) in platelets in coinfected patients compared with monoinfected patients. In conclusion, dengue-malaria coinfection is a reality in Ngaoundere city and associated with the appearance of clinical features which predict the disease severity.

Does Malaria Co-Infection Alter the Clinical Course in Children Infected with Dengue? Analysis from 623 Indian Children Admitted with Dengue Infection

BACKGROUND

Dengue and malaria co-infection has been reported in several case reports. We aim to study effect of malaria co-infection on clinical outcomes of dengue infection.

METHODS

Records of 623 children with dengue infection, based on NS-1 antigen and IgM ELISA testing, were collected. Malaria co-infection was identified in 20 cases, based on peripheral blood smear examination. Clinical and hematological parameters were compared in two groups (malaria co-infection vs. dengue mono-infection).

RESULTS

Duration of hospitalization was significantly higher in co-infected group. Significantly higher proportion of malaria co-infection cases had hepatosplenomegaly, hemoglobin ≤8 g/dl, serum albumin ≤3 g/dl, serum bilirubin ≥1 mg/dl, serum aspartate aminotransferase ≥500 U/l and serum alanine aminotransferase ≥300 U/l. Number of transfusions (PRBC and platelets) required in malaria co-infection group was higher.

CONCLUSION

Malaria co-infection in dengue impacts clinical presentation, hematological parameters, requirement of blood transfusion and morbidity. High index of suspicion is warranted while evaluating febrile patients.

Successful management of dengue in renal transplant recipients: A retrospective cohort from a single center

INTRODUCTION

The literature on dengue infection in renal transplant recipients has shown wide diversity in clinical presentation and outcome. The objective of this study was to report the clinical profile, short-term and long-term outcomes of dengue among renal transplant recipients.

METHODS

A total of 59 post-transplant dengue suspected cases were admitted from July 2019 to April 2020 of which 31 had confirmed dengue infection. The clinical and laboratory profile of the confirmed dengue cases (n = 31) were compared with non-dengue cases (n = 28).

RESULTS

Among the clinical and laboratory features retro-orbital pain, conjunctival redness, thrombocytopenia on admission, and absence of arthralgia were significantly associated with dengue compared to non-dengue cases. No mortality was observed in the dengue cases. Allograft dysfunction, acute rejection and graft losses were identified in 64.5% (n = 20), 6.4% (n = 2) and 6.4% (n = 2) dengue cases respectively. No rejection or graft losses were observed in 1-year follow-up.

CONCLUSIONS

We report a differential clinical profile for dengue in transplant settings which will aid in the diagnosis. We also report successful management of dengue infection in renal transplant recipients with the majority having allograft dysfunction. A long-term follow-up of the cohort was uneventful.

Enhanced passive surveillance dengue infection among febrile children: Prevalence, co-infections and associated factors in Cameroon

Dengue virus (DENV) causes a spectrum of diseases ranging from asymptomatic, mild febrile to a life-threatening illness: dengue hemorrhagic fever. The main clinical symptom of dengue is fever, similar to that of malaria. The prevalence of dengue virus infection, alone or in association with other endemic infectious diseases in children in Cameroon is unknown. The aim of this study was to determine the prevalence of dengue, malaria and HIV in children presenting with fever and associated risk factors.

Dengue overall prevalence was 20.2%, Malaria cases were 52.7% and HIV cases represented 12.6%. The prevalence of dengue-HIV co-infection was 6.0% and that of Malaria-dengue co-infection was 19.5%. Triple infection prevalence was 4.3%. Dengue virus infection is present in children and HIV-Dengue or Dengue- Malaria co-infections are common. Dengue peak prevalence was between August and October. Sex and age were not associated with dengue and dengue co-infections. However, malaria as well as HIV were significantly associated with dengue (P = 0.001 and 0.028 respectively). The diagnosis of dengue and Malaria should be carried out routinely for better management of fever.

Fever is a symptom common to several infectious diseases such as malaria, yellow fever, dengue fever and typhoid which are all present in Cameroon. In most cases, fever in Cameroon is assumed to be due to malaria and treated as such. This study present the prevalence of dengue fever among febrile children. Dengue fever as well as malaria is common among Cameroonian children. Since Cameroon is endemic for malaria, fever may indicate either malaria or dengue. Clinicians should be aware of the presence of dengue in Cameroon. Knowing the risk factors, parents are encouraged to use the bed net to protect their children and clean stagnant water from their environment. Children could be co-infected by dengue, malaria as well as HIV. Management of patients with dengue fever and HIV infection should be studied, especially in infants where both viral diseases are more severe. Close monitoring may prevent complications among HIV-infected individuals who contract dengue fever.

Epidemiology of dengue fever in Gabon: Results from a health facility-based fever surveillance in Lambaréné and its surroundings

Background

In Africa, information on dengue is limited to outbreak reports and focused on some countries with continuing transmission in West and East Africa. To estimate the proportion of dengue-positive cases among febrile patients and identify clinical indicators of dengue cases, we conducted passive facility-based fever surveillance in a catchment area population of 70,000 residents of Lambaréné and its surroundings in Gabon.

Methods

Non-malarial febrile patients with current fever or history of fever (≤7 days) between 1 and 55 years of age, were enrolled at Albert Schweitzer Hospital (ASH). Acute (visit 1, day of enrollment) and convalescent blood samples were collected between 10 and 21 days after enrollment. Acute/convalescent samples were tested with IgM/IgG ELISA, and a selected subset of acute samples with RT-PCR.

Results

Among 682 non-malarial febrile patients enrolled, 119 (17.4%) were identified as dengue-positive (94 dengue-confirmed and 25 dengue-probable cases). Of these dengue-positive cases, 14 were confirmed with PCR, and based on serotyping, two infections were identified to be DENV-2 and two were DENV-3. The majority of our enrolled patients were <25 years of age and close to 80% of our dengue-positive cases were <15 years of age. In adjusted analyses, retro-orbital pain and abdominal pain were 2.7 and 1.6 times more frequently found among dengue-positive cases, compared to non-dengue cases.

Conclusion

Lambaréné is not considered dengue-endemic. However, one in six non-malarial febrile episodes was found to be dengue-positive in the study period. Dengue should be considered more frequently in clinicians’ diagnosis among non-malarial febrile patients in Lambaréné. Given the lack of data on dengue in Gabon, additional prospective and longitudinal studies would help to further define the burden and patterns of dengue for improved case detection.

In Africa, information on dengue is limited to outbreak reports focused on some countries in West and East Africa. To estimate the proportion of dengue-positive cases among febrile patients and identify clinical indicators of dengue cases, we conducted passive health facility-based fever surveillance in a catchment area population of 70,000 residents of Lambaréné and its surroundings, Gabon. Among the patients with negative malaria RDT results, those with current fever or history of fever (≤7 days) between 1 and 55 years of age were enrolled at Albert Schweitzer Hospital (ASH). Two samples were collected with an interval of 10 to 21 days after enrollment. Samples underwent different testing for dengue confirmation. Among 682 febrile patients enrolled, 17.4% were identified as dengue-positive. Of these dengue-positive cases, we found DENV-2 and DENV-3 serotypes. Close to 80% of our dengue-positive cases were < 15 years old. Retro-orbital pain and abdominal pain were more commonly found among dengue-positive cases, compared to non-dengue cases. Lambaréné is not considered dengue-endemic. However, one in six non-malarial febrile episodes was found to be dengue-positive in the study period. Clinicians should consider dengue more frequently among non-malarial febrile patients. Given the lack of data on dengue in Gabon, more data should be generated to understand the burden and patterns of dengue for improved case detection.

Clinical and epidemiologic characteristics associated with dengue fever in Mombasa, Kenya

OBJECTIVES

Information on dengue in Africa is limited. To estimate the proportion of dengue-positive cases among febrile patients and describe clinical indicators of dengue, we conducted passive health facility-based fever surveillance in Mombasa, Kenya.

METHODS

Non-malarial febrile patients between one and 55 years were enrolled at three health facilities between March 2016 and May 2017. Acute and convalescent blood samples were collected with an interval of 10-21 days. Acute samples were tested with dengue RDT and a selected subset with RT-PCR, and acute/convalescent samples with IgM/IgG ELISA.

RESULTS

Among 482 enrollees, 295 (61.2%) were dengue-positive based on laboratory results. The surveillance covered the beginning of a dengue outbreak in April-May 2017, during which 73.9% of enrollees were dengue-positive. By contrast, during the non-outbreak period, 54.6% were dengue-positive. Dengue case status was positively associated with rash, fatigue, headache, retro-orbital pain, nausea/vomiting, nose bleeding, gum bleeding, loss of appetite, myalgia, and arthralgia. Dengue-positive cases in our study had mostly mild disease, with only two requiring observation, and no DHF.

CONCLUSIONS

The clinical response was generally mild relative to what was observed in SE Asia and the Americas. Given the high level of DENV transmission in Mombasa, more data would be needed to further understand the disease burden and improve case detection for surveillance/monitoring of outbreaks.

Prevalence of and risk factors for severe malaria caused by Plasmodium and dengue virus co-infection: a systematic review and meta-analysis

BACKGROUND

Co-infection with both Plasmodium and dengue virus (DENV) infectious species could have serious and fatal outcomes if left undiagnosed and without timely treatment. The present study aimed to determine the pooled prevalence estimate of severe malaria among patients with co-infection, the risk of severe diseases due to co-infection, and to describe the complications of severe malaria and severe dengue among patients with co-infection.

METHODS

Relevant studies published between databases between 12 September 1970 and 22 May 2020 were identified and retrieved through a search of the ISI Web of Science, Scopus, and MEDLINE. The pooled prevalence and 95% confidence interval (CI) of severe malaria among patients with Plasmodium and DENV co-infection was estimated with a random-effects model to take into account the between-study heterogeneity of the included studies. The risks of severe malaria and severe diseases due to co-infection were estimated with the pooled odds ratio (OR) and 95% CI with a random-effects model.

RESULTS

Of the 5653 articles screened, 13 studies were included in the systematic review and meta-analysis. The results demonstrated that the pooled prevalence estimate of severe malaria among patients with co-infection was 32% (95% CI: 18-47%, I² = 92.3%). Patients with co-infection had a higher risk of severe diseases than those with DENV mono-infection (odds ratio [OR] = 3.94, 95% CI: 1.96-7.95, I² = 72%). Patients with co-infection had a higher risk of severe dengue than those with DENV mono-infection (OR = 1.98, 95% CI: 1.08-3.63, I² = 69%). The most severe complications found in severe dengue were bleeding (39.6%), jaundice (19.8%), and shock/hypotension (17.9%), while the most severe complications found in severe malaria were severe bleeding/bleeding (47.9%), jaundice (32.2%), and impaired consciousness (7.43%).

CONCLUSIONS

The present study found that there was a high prevalence of severe malaria among patients with Plasmodium and DENV co-infection. Physicians in endemic areas where these two diseases overlap should recognize that patients with this co-infection can develop either severe malaria or severe dengue with bleeding complications, but a greater risk of developing severe dengue than severe malaria was noted in patients with this co-infection.

TRIAL REGISTRATION

The protocol of this study was registered at PROSPERO: CRD42020196792 .

Severity and costs associated with hospitalization for dengue in public and private hospitals of Surat city, Gujarat, India, 2017-2018

BACKGROUND

Dengue is major public health problem in India, especially in urban areas. We conducted a study to estimate the severity and costs of treatment among hospitalized dengue patients in Surat city, Gujarat, India.

METHODS

We reviewed the medical records of dengue patients hospitalized in five tertiary care facilities (private [n=2], semi-government [n=2] and government [n=1]) between April 2017 and March 2018. We used the World Health Organization 2009 classification to classify the severity of dengue. A resource utilization approach was used to estimate the cost of illness in US dollars (US$) (inflation adjusted to 2018) from a quasi-societal perspective (excluding non-medical cost) for dengue hospitalization.

RESULTS

Of the 732 hospitalized dengue patients, 44.7% had no warning symptoms, 39.5% had warning signs and 15.8% had severe dengue. The mean cost of hospitalization was US$86.9±170.7. The cost of hospitalization was 28.8 times higher in private hospitals compared with government hospitals. Consultant charges in private hospitals, laboratory investigations in semi-government hospitals and registration with admission charges in government hospitals accounted for 27.3%, 39.4% and 53% of the direct cost in these facilities, respectively.

CONCLUSIONS

A better triage system for hospitalization, subsidizing costs in the public sector and cost capping in the private sector can help to reduce the cost of hospitalization due to dengue so as to ensure affordability for larger portion of the society for universal health coverage.

Complex interactions between bacteria and haemosporidia in coinfected hosts: An experiment

Hosts are typically coinfected by multiple parasite species whose interactions might be synergetic or antagonistic, producing unpredictable physiological and pathological impacts on the host. This study shows the interaction between Plasmodium spp. and Leucocytozoon spp. in birds experimentally infected or not infected with Mycoplasma gallisepticum.In 1994, the bacterium Mycoplasma gallisepticum jumped from poultry to wild birds in which it caused a major epidemic in North America. Birds infected with M. gallisepticum show conjunctivitis as well as increased levels of corticosterone.Malaria and other haemosporidia are widespread in birds, and chronic infections become apparent with the detectable presence of the parasite in peripheral blood in response to elevated levels of natural or experimental corticosterone levels.Knowing the immunosuppressive effect of corticosterone on the avian immune system, we tested the hypothesis that chronic infections of Plasmodium spp. and Leucocytozoon spp. in house finches would respond to experimental inoculation with M. gallisepticum as corticosterone levels are known to increase following inoculation. Plasmodium spp. infection intensity increased within days of M. gallisepticum inoculation as shown both by the appearance of infected erythrocytes and by the increase in the number and the intensity of positive PCR tests. Leucocytozoon spp. infection intensity increased when Plasmodium spp. infection intensity increased, but not in response to M. gallisepticum inoculation. Leucocytozoon spp. and Plasmodium spp. seemed to compete in the host as shown by a negative correlation between the changes in their PCR score when both pathogens were present in the same individual.Host responses to coinfection with multiple pathogens measured by the hematocrit and white blood cell count depended on the haemosporidian community composition. Host investment in the leukocyte response was higher in the single-haemosporidia-infected groups when birds were infected with M. gallisepticum.A trade-off was observed between the immune control of the chronic infection (Plasmodium spp./Leucocytozoon spp.) and the immune response to the novel bacterial infection (M. gallisepticum).

Spatial Assessment of Contact Between Humans and Anopheles and Aedes Mosquitoes in a Medium-Sized African Urban Setting, Using Salivary Antibody-Based Biomarkers

BACKGROUND

Anarchic and poorly controlled urbanization led to an increased risk of mosquito-borne diseases (MBD) in many African cities. Here, we evaluate the spatial heterogeneity of human exposure to malaria and arboviral disease vectors in an urban area of northern Senegal, using antibody-based biomarkers of exposure to Anopheles and Aedes mosquito bites.

METHODS

A cross-sectional study was undertaken during the rainy season of 2014 in 4 neighborhoods of Saint-Louis, a city in northern Senegal. Among children aged 6-59 months in each neighborhood, the dried blood spot technique was used to evaluate immunoglobulin G (IgG) responses to both gSG6-P1 (Anopheles) and Nterm-34-kDa (Aedes) salivary peptides as validated biomarkers of respective mosquito bite exposure.

RESULTS

IgG response levels to gSG6-P1 and Nterm-34-kDa salivary peptides varied significantly between the 4 neighborhoods (P < .0001). The level of exposure to Aedes bites also varied according to household access to sanitation services (P = .027), whereas that of exposure to Anopheles bites varied according to insecticide-treated bed net use (P = .006). In addition, spatial clusters of high contact between humans and mosquitoes were identified inside 3 neighborhoods.

CONCLUSIONS

Antibody-based biomarkers of exposure to Anopheles and Aedes mosquito bites could be helpful tools for evaluating the heterogeneity of exposure to malaria and arboviral disease vectors by national control programs.

Clinical and epidemiologic characteristics associated with dengue during and outside the 2016 outbreak identified in health facility-based surveillance in Ouagadougou, Burkina Faso

Background

In Africa, the magnitude of dengue virus (DENV) transmission is largely unknown. In Burkina Faso, several outbreaks have been reported and data are often based on findings from outbreak investigations.

Methods

To better understand dengue epidemiology and clinical characteristics in Burkina Faso, a fever surveillance study was conducted among patients aged 1–55 years, who presented with non-malarial febrile illness at five primary healthcare facilities in Ouagadougou, Burkina Faso from December 2014 to February 2017, encompassing a 3-month dengue outbreak in September-November 2016. Acute and convalescent blood samples were collected within an interval of 10–21 days between visits. Acute samples were tested with dengue rapid diagnostic tests (RDT) and a selected subset with RT-PCR, and all acute/convalescent samples with IgM/IgG ELISA.

Results

Among 2929 non-malarial febrile patients, 740 (25%) were dengue–positive based on RT-PCR and/or IgM/IgG ELISA; 428 out of 777 patients (55%) and 312 out of 2152 (14%) were dengue-positive during outbreak and non-outbreak periods, respectively. There were 11% (316/2929) and 4% (129/2929) patients showing positive for NS1 and IgM, on the RDT, respectively. DENV 2 predominated during the outbreak, whereas DENV 3 predominated before the outbreak. Only 25% of dengue-positive cases were clinically diagnosed with suspected dengue. The odds of requiring observation for ≤3 days (versus routine outpatient care) were 11 times higher among dengue-positive cases than non-dengue cases. In adjusted analyses, dengue-positivity was associated with rash and retro-orbital pain (OR = 2.6 and 7.4, respectively) during the outbreak and with rash and nausea/vomiting (OR = 1.5 and 1.4, respectively) during the non-outbreak period.

Conclusion

Dengue virus is an important pathogen in Burkina Faso, accounting for a substantial proportion of non-malarial fevers both during and outside outbreak, but is only infrequently suspected by clinicians. Additional longitudinal data would help to further define characteristics of dengue for improved case detection and surveillance.

There is not much evidence on dengue in Africa, relative to the Asia-Pacific and Latin American regions. To estimate the proportion of dengue among patients with fever, and to identify clinical features of dengue during outbreak and non-outbreak periods, we studied 2929 patients with non-malarial fever, aged 1–55 years, who attended five primary healthcare centers in Ouagadougou, Burkina Faso. Patients were tested with a rapid test for dengue, and further tests were carried out on paired blood samples taken 10–21 days apart. Overall, a quarter of non-malarial febrile episodes identified between December 2014 and February 2017 were dengue-positive. Dengue-positive cases were 11 times more likely than non-dengue cases to require observation for ≤3 days. During the study period in 2016, there was a dengue outbreak where more than half of non-malarial febrile patients were identified to be dengue-positive. DENV 2 was the main serotype in circulation during the outbreak, whereas DENV 3 was the main serotype before the outbreak. Rash and retro-orbital pain were more frequently found among dengue-positive cases, compared to non-dengue cases, during the outbreak. During the non-outbreak period, rash and nausea/vomiting were more likely in dengue-positive versus non-dengue cases. There was a low level of clinical suspicion of dengue even during the 2016 outbreak. Therefore, a broader use of rapid diagnostic tests and more epidemiologic data would help to improve dengue case detection and surveillance in Burkina Faso.

Prevalence and laboratory analysis of malaria and dengue co-infection: a systematic review and meta-analysis

Background

A clear understanding of the epidemiology of malaria and dengue co-infection is essential for informed decisions on appropriate control strategies for dengue and malaria. This systematic review synthesized evidence on the relationship of malaria and dengue co-infection and related it to alterations in platelet, hemoglobin, hematocrit, aspartate aminotransferase (AST), and alanine aminotransferase (ALT) levels when compared to malaria mono-infection.

Methods

A systematic review in accordance with PRISMA guidelines was conducted. All published articles available in PubMed and Web of Science (ISI) databases before October 21, 2017 were recruited. All epidemiological studies except case reports on the prevalence or incidence of malaria and dengue co-infection among patients visiting hospitals with febrile illness were included. Studies that involved conference abstracts, protocols, systematic reviews, only mono-dengue or mono-malaria infections, and only animal or in vitro studies were excluded after screening the titles, abstracts, and body texts. Studies were additionally excluded after full text review when they lacked epidemiologic data on malaria and dengue co-infection. Two reviewers independently screened, reviewed, and assessed all the studies. Cochrane Q (Chi-square) and Moran’s I² were used to assess heterogeneity, and the funnel plot was used to examine publication bias. The summary odds ratio (OR) and 95% confidence intervals (CI) were estimated using a fixed-effects model. Thirteen cross-sectional and two retrospective studies were eligible to be included in the systematic review and meta-analysis.

Results

Out of the 2269 citations screened, 15 articles were eligible to be included in the systematic review and meta-analysis. The 15 studies involved 13,798 (10,373 cases with malaria and 3425 with dengue) patients in 9 countries. Thirteen studies compared the incidence and odds of Plasmodium sp. infection, five studies compared the odds of mean platelet, three studies compared Plasmodium parasite density, and four studies compared the odds of hemoglobin, hematocrit, AST, and ALT levels among co-infected groups and single-malaria-infected groups.

Conclusions

This study showed that dengue and malaria co-infection was associated with decreased odds of malaria infection, malaria parasitemia, AST, and ALT levels when compared to malaria mono-infection. However, malaria and dengue co-infection was associated with increased odds of platelet and hemoglobin levels when compared to malaria mono-infection.

Electronic supplementary material

The online version of this article (10.1186/s12889-019-7488-4) contains supplementary material, which is available to authorized users.

Case Report: Typhoid Fever and Spotted Fever Group Rickettsiosis Presenting Concomitantly in an Indian Immigrant

We present a rare case of an Indian immigrant suffering from concomitant infection of Salmonella typhi and spotted fever group Rickettsia. We discuss the scarce reports of dual infections from the developing world and the related diagnostic challenges.

Prevalence of Zika and malaria in patients with fever in secondary healthcare facilities in south-eastern Nigeria

We describe the frequency of Zika and malaria among patients presenting with fever to secondary health facilities in Cross River State, Nigeria. Using a cross-sectional, stratified survey design, we randomly selected nine facilities and consecutively recruited 100 participants (aged ≥ 1 year) who presented with fever. On testing blood samples using Biocan qualitative lateral flow immuno-chromatographic cassettes for Zika IgG and IgM, 10% were seropositive for Zika virus (ZIKV) IgM, 12% for ZIKV IgG and 20% for ZIKV IgM, IgG or both. Following microscopy of thick films stained with Giemsa for malaria parasites, 55% were positive for malaria and 15% were positive for both malaria and ZIKV IgM, IgG or both. A moderately negative association between urban and rural household location and seropositivity for ZIKV IgM or IgG was found on logistic regression. Our results clearly indicate a high rate of probable ZIKV and malaria co-incidence in Cross River State. Given the high risk of serious fetal outcomes following ZIKV infection, further epidemiological research and surveillance systems for ZIKV are clearly required.

Collateral Presentation of Malaria and Dengue Viral Hemorrhagic Fever: A Rare Case

Cases on concurrent infection of dengue and malaria are uncommon in Pakistan. Dengue and malaria are the two very common, mosquito-borne infections, which may have significant morbidity and mortality if not managed properly. Concurrent infections of dengue and malaria are rare due to the different habitats of its vectors and activities of different bearer mosquitoes. The first case was reported in 2005. Since then, several co-existing infections have been reported consisting of the dengue virus (DENV) and the malaria protozoans. Symptoms of each infection may be disguised by a coincident second infection, resulting in delayed treatment and severe complications. We report a case of concurrent malaria and dengue viral hemorrhagic fever in a 19-year-old male.

ConcomitantPlasmodium vivaxmalaria and murine typhus infection with pulmonary involvement

We report a case of Plasmodium vivax and murine typhus coinfection in a 30-year-old woman who presented with intermittent, high-grade fever. Her peripheral blood smear showed ring-form trophozoites of P. vivax, with an initial murine typhus serological test being negative. Although the P. vivax infection was successfully treated, she still had intermittent, high-grade fever, developed dyspnoea and bilateral interstitial pneumonitis shown in the chest X-ray. Thus, coinfection was suspected, and empirical antibiotics were given. The second serological test confirmed the concomitant murine typhus infection, and antibiotics treatment were successful with the complete recovery. This case emphasises that an initial negative murine typhus serological test does not necessarily rule out the presence of the disease. A follow-up murine typhus serological or molecular test within 1–2 weeks is therefore recommended.

Seroprevalence of dengue virus among children presenting with febrile illness in some public health facilities in Cameroon

INTRODUCTION

A routine diagnosis of Dengue virus (DENV) infection is not usually conducted in hospitals. Because symptoms overlap, many potential febrile illnesses due to DENV may be confused for malaria, typhoid or paratyphoid (enteric) fever. The absence of data on DENV exposure rates among children attending health facilities could undermine management of this disease. This study aimed to investigate the seroprevalence of dengue virus infection in children presenting febrile illness in some public health facilities in Cameroon.

METHODS

A cross-sectional study was performed in children ≤ 15 years attending seven urban and three semi-urban public hospitals of Cameroon. From each volunteer, 2ml of whole blood was collected and tested for dengue virus IgM, malaria (Pf/Pan antigens) and enteric fever (Typhoid IgM) using rapid diagnostic tests (RDT); in order to allow the healthcare workers to quickly put the positive cases under appropriate treatment. Positive cases of dengue virus infection were confirmed by indirect ELISA. Data analysis were performed using the statistical package for social sciences software, version 22.1.

RESULTS

A total of 961 children were enrolled in the study and 492 (51.2%) were infected with at least one of the three pathogens. Overall, DENV IgM seroprevalence among febrile children was 14.4% (138/961). About 390 (40.6%) and 22 (2.3%) had malaria (Pf/Pan Ag) and enteric fever (Typhoid IgM) respectively. Co-infection with dengue virus was found in 51 (5.3%) participants. The dengue virus IgM seroprevalence was higher in Bankim (19.3%), Ntui (18.3%) and Douala (18.2%).

CONCLUSION

Dengue virus infection seroprevalence appears to be low in children presenting with febrile illness in the studied health centres in Cameroon but call for more attention and research to further characterise the circulating strains of the dengue virus.

Insecticide space spraying for preventing malaria transmission

BACKGROUND

Space spraying is the dispersal of a liquid fog of insecticide into an outdoor area to kill adult insects. It has been regularly used in public health and pest control programmes, including use as an emergency response to malaria epidemics. This Cochrane Review aims to assist the decision-making of malaria vector control programmes by summarizing the evidence of the impact of space spraying on malaria transmission.

OBJECTIVES

The review's primary objective was to evaluate the impact of space spraying on malaria transmission, or the incremental impact when applied in combination with other malaria control methods, in comparison to equivalent conditions with no space spraying intervention.To guide future evaluations of space spraying, a secondary objective was to identify and summarize the range of space spraying strategies that have been trialled, those which were promising and warrant further evaluation, and those which appear unlikely to warrant further evaluation (for example, if they were not feasible to implement, or were unacceptable to the population).

SEARCH METHODS

We searched the Cochrane Infectious Diseases Group Specialized Register; the Cochrane Central Register of Controlled Trials (CENTRAL), published in the Cochrane Library; PubMed (MEDLINE); Embase (OVID), CAB Abstracts (Web of Science), LILACS (BIREME), the World Health Organization (WHO) International Clinical Trials Registry Platform, and ClinicalTrials.gov up to 18 April 2018. We contacted organizations for ongoing and unpublished trials, and checked the reference lists of all included studies for relevant studies.

SELECTION CRITERIA

We included cluster-randomized controlled trials, interrupted time series (ITS) studies, randomized cross-over studies, and controlled before-and-after (CBA) studies comparing space spraying with no space spraying that met the inclusion criteria for the review.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for eligibility and risk of bias, and extracted the data. For ITS studies, we present findings graphically, and estimated the effect of space spraying on the step change and the slope change. We assessed the certainty of evidence using the GRADE approach.

MAIN RESULTS

Two ITS studies, conducted between 1972 and 1984, met our inclusion criteria for the primary objective, and one study contributed to the quantitative analysis. This study was conducted in India, reported the incidence of malaria in four separate sites, and covered a total population of 18,460 people. In the pooled analysis across sites, there was no step effect for the incidence of uncomplicated malaria (step rate ratio 1.00, 95% confidence interval (CI) 0.51 to 1.92). There was an effect on the slope: the number of cases was reduced by 15% per month (slope rate ratio 0.85, 95% CI 0.79 to 0.91). Using these ratios, we estimated the effect of 12 months of space spraying on malaria incidence to be a reduction from 6 cases to 1 case per month per 1000 population (95% CI 0 to 2 cases, very low-certainty evidence). The second study reported the impact of space spraying on malaria incidence and adult mosquito density in a population of 15,106 in Haiti, but it did not provide data from previous years. Thus, we could not estimate an effect of space spraying that was independent from temporal trends.For the review's secondary objective, we identified a further two studies in addition to the two ITS studies; both used a CBA design and were conducted between 1973 and 2000. The four studies used a range of delivery methods including handheld, vehicle-mounted, and aircraft-mounted spraying equipment. A variety of insecticides, doses, and spraying times were also used, with methods typically determined based on environmental factors and vector profiles.

AUTHORS' CONCLUSIONS

Evidence from one state in India conducted over 30 years ago suggests an effect of space spraying on the incidence of malaria, but the certainty of the evidence is very low. Reliable research in a variety of settings will help establish whether and when this intervention may be worthwhile.

Global prevalence and distribution of coinfection of malaria, dengue and chikungunya: a systematic review

BACKGROUND

Malaria, Dengue and Chikungunya are vector borne diseases with shared endemic profiles and symptoms. Coinfections with any of these diseases could have fatal outcomes if left undiagnosed. Understanding the prevalence and distribution of coinfections is necessary to improve diagnosis and designing therapeutic interventions.

METHODS

We have carried out a systematic search of the published literature based on PRISMA guidelines to identify cases of Malaria, Dengue and Chikungunya coinfections. We systematically reviewed the literature to identify eligible studies and extracted data regarding cases of coinfection from cross sectional studies, case reports, retrospective studies, prospective observational studies and surveillance reports.

RESULTS

Care full screening resulted in 104 publications that met the eligibility criteria and reported Malaria/Dengue, Dengue/Chikungunya, Malaria/Chikungunya and Malaria/Dengue/Chikungunya coinfections. These coinfections were spread over six geographical locations and 42 different countries and are reported more frequently in the last 15 years possibly due to expanding epidemiology of Dengue and Chikungunya. Few of these reports have also analysed distinguishing features of coinfections. Malaria/Dengue coinfections were the most common coinfection followed by Dengue/Chikungunya, Malaria/Chikungunya and Malaria/Dengue/Chikungunya coinfections. P. falciparum and P. vivax were the commonest species found in cases of malaria coinfections and Dengue serotype-4 commonest serotype in cases of dengue coinfections. Most studies were reported from India. Nigeria and India were the only two countries from where all possible combinations of coinfections were reported.

CONCLUSION

We have comprehensively reviewed the literature associated with cases of coinfections of three important vector borne diseases to present a clear picture of their prevalence and distribution across the globe. The frequency of coinfections presented in the study suggests proper diagnosis, surveillance and management of cases of coinfection to avoid poor prognosis of the underlying etiology.

Elimination of Falciparum Malaria and Emergence of Severe Dengue: An Independent or Interdependent Phenomenon?

The global malaria burden, including falciparum malaria, has been reduced by 50% since 2000, though less so in Sub-Saharan Africa. Regional malaria elimination campaigns beginning in the 1940s, up-scaled in the 1950s, succeeded in the 1970s in eliminating malaria from Europe, North America, the Caribbean (except Haiti), and parts of Asia and South- and Central America. Dengue has grown dramatically throughout the pantropical regions since the 1950s, first in Southeast Asia in the form of large-scale epidemics including severe dengue, though mostly sparing Sub-Saharan Africa. Globally, the WHO estimates 50 million dengue infections every year, while others estimate almost 400 million infections, including 100 million clinical cases. Curiously, despite wide geographic overlap between malaria and dengue-endemic areas, published reports of co-infections have been scarce until recently. Superimposed acute dengue infection might be expected to result in more severe combined disease because both pathogens can induce shock and hemorrhage. However, a recent review found no reports on more severe morbidity or higher mortality associated with co-infections. Cases of severe dual infections have almost exclusively been reported from South America, and predominantly in persons infected by Plasmodium vivax. We hypothesize that malaria infection may partially protect against dengue – in particular falciparum malaria against severe dengue – and that this inter-species cross-protection may explain the near absence of severe dengue from the Sub-Saharan region and parts of South Asia until recently. We speculate that malaria infection elicits cross-reactive antibodies or other immune responses that infer cross-protection, or at least partial cross-protection, against symptomatic and severe dengue. Plasmodia have been shown to give rise to polyclonal B-cell activation and to heterophilic antibodies, while some anti-dengue IgM tests have high degree of cross-reactivity with sera from malaria patients. In the following, the historical evolution of falciparum malaria and dengue is briefly reviewed, and we explore early evidence of subclinical dengue in high-transmission malaria areas as well as conflicting reports on severity of co-morbidity. We also discuss examples of other interspecies interactions.

First documented evidence of dengue and malaria co-infection in children attending two health centers in Yaoundé, Cameroon

To date, only a few cases of malaria and dengue co-infections have been reported around the world. We describe for the first time in Cameroon, concurrent infections among children (2 to 10 years) in two health centers of Yaoundé. The two dengue strains isolated in Cameroon clustered with the Asian II genotype. Although acute concurrent infections were benign, special attention should be given to malaria and dengue co-infection in order to prevent possible severe cases.

Severe Cerebral Falciparum Malaria with Dengue Coinfection: A Case Report

A rare severe case of the coinfection of cerebral falciparum malaria and dengue is reported in this paper. The patient was a 50 yr old male in the north of China, who returned from Uganda not long ago and suffered unconsciousness after fever for 4 d before the falciparum malaria and dengue infection was diagnosed via blood smear microscopy, RT-PCR and serology, although the antimalarial and symptomatic treatment was carried out, ultimately the patients died of septic shock because of multiple organ dysfunctions. This case report showed such a coinfection was prone to cause severe acute consequence. The timely diagnosis and delicate treatment are crucial for prognosis of patients.

Microbial Pre-exposure and Vectorial Competence of Anopheles Mosquitoes

Anopheles female mosquitoes can transmit Plasmodium, the malaria parasite. During their aquatic life, wild Anopheles mosquito larvae are exposed to a huge diversity of microbes present in their breeding sites. Later, adult females often take successive blood meals that might also carry different micro-organisms, including parasites, bacteria, and viruses. Therefore, prior to Plasmodium ingestion, the mosquito biology could be modulated at different life stages by a suite of microbes present in larval breeding sites, as well as in the adult environment. In this article, we highlight several naturally relevant scenarios of Anopheles microbial pre-exposure that we assume might impact mosquito vectorial competence for the malaria parasite: (i) larval microbial exposures; (ii) protist co-infections; (iii) virus co-infections; and (iv) pathogenic bacteria co-infections. In addition, significant behavioral changes in African Anopheles vectors have been associated with increasing insecticide resistance. We discuss how these ethological modifications may also increase the repertoire of microbes to which mosquitoes could be exposed, and that might also influence their vectorial competence. Studying Plasmodium–Anopheles interactions in natural microbial environments would efficiently contribute to refining the transmission risks.

C-reactive protein is differentially modulated by co-existing infections, vitamin deficiencies and maternal factors in pregnant and lactating indigenous Panamanian women

Background

The usefulness of C-reactive protein (CRP) as a non-specific marker of inflammation during pregnancy and lactation is unclear in impoverished populations where co-existing infections and vitamin deficiencies are common.

Methods

This cross-sectional study in Panama recruited 120 pregnant and 99 lactating Ngäbe-Buglé women from 14 communities in rural Panama. Obstetric history, indoor wood smoke exposure, fieldwork, BMI, vitamins A, B₁₂, D, and folic acid, and inflammation markers (CRP, neutrophil/lymphocyte ratio (NLR), plateletcrit and cytokines) were measured. Multiple regressions explored both associations of CRP with other inflammatory markers and associations of CRP and elevated CRP based on trimester-specific cut-offs with maternal factors, infections and vitamin deficiencies.

Results

CRP was higher in pregnancy (51.4 ± 4.7 nmol/L) than lactation (27.8 ± 3.5 nmol/L) and was elevated above trimester specific cut-offs in 21% of pregnant and 30% of lactating women. Vitamin deficiencies were common (vitamin A 29.6%; vitamin D 68.5%; vitamin B₁₂ 68%; folic acid 25.5%) and over 50% of women had two or more concurrent deficiencies as well as multiple infections. Multiple regression models highlighted differences in variables associated with CRP between pregnancy and lactation. In pregnancy, CRP was positively associated with greater indoor wood smoke exposure, caries and hookworm and negatively associated with Ascaris and vaginal Lactobacillus and Bacteroides/Gardnerella scores. Consistent with this, greater wood smoke exposure, caries as well as higher diplococcal infection score increased the odds of trimester-elevated CRP concentrations whereas longer gestational age lowered the likelihood of a trimester-elevated CRP. During lactation, folic acid deficiency was associated with higher CRP whereas parity, number of eosinophils and Mobiluncus score were associated with lower CRP. Also, a higher BMI and Trichomonas vaginalis score increased the likelihood of an elevated CRP whereas higher parity and number of eosinophils were associated with lower likelihood of an elevated CRP.

Conclusions

Infections both raise and lower CRP concentrations in pregnant and lactating mothers. Only folic acid deficiency during lactation was associated with higher CRP concentrations. Caution is required when interpreting CRP concentrations in pregnant and lactating women who have co-existing nutrient deficiencies and multiple infections.

Electronic supplementary material

The online version of this article (doi:10.1186/s40249-017-0307-1) contains supplementary material, which is available to authorized users.

Imported Dengue Infection in a Spanish Hospital with a High Proportion of Travelers from Africa: A 9-Year Retrospective Study

Epidemiological data on dengue in Africa are still scarce. We investigated imported dengue infection among travelers with a high proportion of subjects from Africa over a 9-year period. From January 2005 to December 2013, blood samples from travelers with clinical suspicion of dengue were analyzed. Dengue was diagnosed using serological, antigen detection, and molecular methods. Subjects were classified according to birthplace (Europeans versus non-Europeans) and last country visited. Overall, 10,307 serum samples corresponding to 8,295 patients were studied; 62% were European travelers, most of them from Spain, and 35.9% were non-Europeans, the majority of whom were born in Africa (mainly Equatorial Guinea) and Latin America (mainly Bolivia, Ecuador, and Colombia). A total of 492 cases of dengue were identified, the highest number of cases corresponding to subjects who had traveled from Africa (N = 189), followed by Latin America (N = 174) and Asia (N = 113). The rate of cases for Africa (4.5%) was inferior to Asia (9%) and Latin America (6.1%). Three peaks of dengue were found (2007, 2010, and 2013) which correlated with African cases. A total of 2,157 of past dengue infections were diagnosed. Non-Europeans who had traveled from Africa had the highest rate of past infection (67.8%), compared with non-Europeans traveling from Latin America (38.7%) or Asia (35%). Dengue infection in certain regions of Africa is underreported and the burden of the disease may have a magnitude similar to endemic countries in Latin America. It is necessary to consider dengue in the differential diagnosis of other febrile diseases in Africa.

Dengue virus and malaria concurrent infection among febrile subjects within Ilorin metropolis, Nigeria

Dengue is a mosquito-borne disease of public health importance. It is caused by four serotypes of Dengue virus (i.e, DENV-1, -2, -3, and -4). As a result of practices that are conducive for mosquito breading, its vector is widespread in Nigeria and this could result to possible DENV outbreaks in Nigeria and beyond. This study aimed to assess the recency of DENV infection as well as occurrence of DENV and Malaria co-infections within Ilorin, Nigeria. Blood samples were obtained from 176 febrile subjects and analyzed using Enzyme Linked Immunosorbent Assay (ELISA) for the presence of DENV antibodies. Malaria infection was detected using a rapid diagnostic test kit for malaria parasites. Malaria and DENV (IgM positive) co-infected samples were further subjected to RT-qPCR analysis. A seroprevalence of 46.0% was recorded for anti-DENV IgM antibodies and 2.84% for concurrent Dengue and malaria infections. Out of 95 IgM negative samples, 48 were found to be positive for DENV IgG antibodies. Eleven (6.25%) samples were confirmed DENV positive following RT-qPCR. The CT values of the amplicons were between 19.0 and 20.0. DENV serotype 2 dominated the study, while serotype 3 and 4 were equally distributed. Based on the high seroprevalence of DENV obtained in this study, there is a high possibility of experiencing Dengue virus outbreak in Ilorin, Nigeria, not neglecting the fast geographical spread of the vector. Therefore, surveillance and intensive vector control program should be instituted.

Differentiating between dengue fever and malaria using hematological parameters in endemic areas of Thailand

Background

Dengue fever (DF) and malaria are the two major public health concerns in tropical countries such as Thailand. Early differentiation between dengue and malaria could help clinicians to identify patients who should be closely monitored for signs of dengue hemorrhagic fever or severe malaria. This study aims to build knowledge on diagnostic markers that are used to discriminate between the infections, which frequently occur in malaria-endemic areas, such as the ones in Thailand.

Methods

A retrospective study was conducted in Phop Phra Hospital, a hospital located in the Thailand-Burma border area, a malaria-endemic area, between 2013 and 2015. In brief, data on 336 patients infected with malaria were compared to data on 347 patients infected with DF.

Results

White blood cells, neutrophil, monocyte, eosinophil, neutrophil-lymphocyte ratio, and monocyte-lymphocyte ratio were significantly lower in patients with DF compared to patients with malaria (P < 0.0001). In contrast, red blood cells, hemoglobin, hematocrit, mean corpuscular volume, mean corpuscular hemoglobin, and mean corpuscular hemoglobin concentration were significantly higher in patients with DF as compared to patients with malaria (P < 0.0001). A decision tree model revealed that using neutrophils, lymphocyte, MCHC, and gender was guided to discriminate between dengue and malaria infection.

Conclusion

This study concluded that several hematological parameters were different for diagnosing DF and malaria. A decision tree model revealed that using neutrophils, lymphocyte, MCHC, and gender was guided to discriminate patients with dengue and malaria infection. In addition, using these markers will thus lead to early detection, diagnosis, and prompt treatment of these tropical diseases.

Electronic supplementary material

The online version of this article (doi:10.1186/s40249-017-0238-x) contains supplementary material, which is available to authorized users.

The dangers of accepting a single diagnosis: case report of concurrent Plasmodium knowlesi malaria and dengue infection

Background

Dengue and malaria are two common, mosquito-borne infections, which may lead to mortality if not managed properly. Concurrent infections of dengue and malaria are rare due to the different habitats of its vectors and activities of different carrier mosquitoes. The first case reported was in 2005. Since then, several concurrent infections have been reported between the dengue virus (DENV) and the malaria protozoans, Plasmodium falciparum and Plasmodium vivax. Symptoms of each infection may be masked by a simultaneous second infection, resulting in late treatment and severe complications. Plasmodium knowlesi is also a common cause of malaria in Malaysia with one of the highest rates of mortality. This report is one of the earliest in literature of concomitant infection between DENV and P. knowlesi in which a delay in diagnosis had placed a patient in a life-threatening situation.

Case presentation

A 59-year old man staying near the Belum-Temengor rainforest at the Malaysia–Thailand border was admitted with fever for 6 days, with respiratory distress. His non-structural protein 1 antigen and Anti-DENV Immunoglobulin M tests were positive. He was treated for severe dengue with compensated shock. Treating the dengue had so distracted the clinicians that a blood film for the malaria parasite was not done. Despite aggressive supportive treatment in the intensive care unit (ICU), the patient had unresolved acidosis as well as multi-organ failure involving respiratory, renal, liver, and haematological systems. It was due to the presentation of shivering in the ICU, that a blood film was done on the second day that revealed the presence of P. knowlesi with a parasite count of 520,000/μL. The patient was subsequently treated with artesunate-doxycycline and made a good recovery after nine days in ICU.

Conclusions

This case contributes to the body of literature on co-infection between DENV and P. knowlesi and highlights the clinical consequences, which can be severe. Awareness should be raised among health-care workers on the possibility of dengue-malaria co-infection in this region. Further research is required to determine the real incidence and risk of co-infection in order to improve the management of acute febrile illness.

Natural Mosquito-Pathogen Hybrid IgG4 Antibodies in Vector-Borne Diseases: A Hypothesis

Chronic exposure to antigens may favor the production of IgG4 antibodies over other antibody types. Recent studies have shown that up to a 30% of normal human IgG4 is bi-specific and is able to recognize two antigens of different nature. A requirement for this specificity is the presence of both eliciting antigens in the same time and at the same place where the immune response is induced. During transmission of most vector-borne diseases, the pathogen is delivered to the vertebrate host along with the arthropod saliva during blood feeding and previous studies have shown the existence of IgG4 antibodies against mosquito salivary allergens. However, there is very little ongoing research or information available regarding IgG4 bi-specificity with regard to infectious disease, particularly during immune responses to vector-borne diseases, such as malaria, filariasis, or dengue virus infection. Here, we provide background information and present our hypothesis that IgG4 may not only be a useful tool to measure exposure to infected mosquito bites, but that these bi-specific antibodies may also play an important role in modulation of the immune response against malaria and other vector-borne diseases in endemic settings.

Symptoms and Immune Markers in Plasmodium/Dengue Virus Co-infection Compared with Mono-infection with Either in Peru

Background

Malaria and dengue are two of the most common vector-borne diseases in the world, but co-infection is rarely described, and immunologic comparisons of co-infection with mono-infection are lacking.

Methodology and Principal Findings

We collected symptom histories and blood specimens from subjects in a febrile illness surveillance study conducted in Iquitos and Puerto Maldonado, Peru, between 2002–2011. Nineteen symptoms and 18 immune markers at presentation were compared among those with co-infection with Plasmodium/dengue virus (DENV), Plasmodium mono-infection, and DENV mono-infection. Seventeen subjects were identified as having Plasmodium/DENV co-infection and were retrospectively matched with 51 DENV mono-infected and 44 Plasmodium mono-infected subjects. Those with Plasmodium mono-infection had higher levels of IL-4, IL-6, IL-10, IL-12, IL-13, IL-17A, IFN-γ, and MIP1-α/CCL3 compared with DENV mono-infection or co-infection; those with Plasmodium mono-infection had more cough than those with DENV mono-infection. Subjects with DENV mono-infection had higher levels of TGF-β1 and more myalgia than those with Plasmodium mono-infection. No symptom was more common and no immune marker level was higher in the co-infected group, which had similar findings to the DENV mono-infected subjects.

Conclusions/Significance

Compared with mono-infection with either pathogen, Plasmodium/DENV co-infection was not associated with worse disease and resembled DENV mono-infection in both symptom frequency and immune marker level.

Dengue and malaria are two of the most important diseases spread by mosquitoes. Clinical manifestations of both febrile diseases overlap considerably, and either can be fatal. In addition, they are co-endemic in many places throughout the world. Despite this, only a handful of reports of co-infection with dengue virus and Plasmodium species are reported in the literature. Through our febrile surveillance program in the Peruvian Amazon, we were able to retrospectively identify 17 cases of co-infection with dengue virus and Plasmodium. Our study aimed to assess whether co-infection was associated with more symptoms or a different immune response compared with mono-infection alone. To answer this question, we utilized data and blood specimens collected during the acute presentation of these 17 subjects and compared them to a matched group of subjects with either dengue virus mono-infection or Plasmodium mono-infection. Our findings indicate co-infection with both pathogens was not associated with more symptoms and the immune profile of co-infection resembled dengue virus mono-infection more than Plasmodium mono-infection.

Laboratory-acquired dengue virus infection by needlestick injury: a case report, South Korea, 2014

Background

Dengue fever is one of the most dominant vector-borne diseases, putting approximately 3.9 billion people at risk worldwide. While it is generally vector-borne, other routes of transmission such as needlestick injury are possible. Laboratory workers can be exposed to dengue virus transcutaneously by needlestick injury. This is the first case, to our knowledge, of dengue virus infection by needlestick injury in a laboratory environment. This paper evaluates the risk and related health concerns of laboratory workers exposed to dengue virus.

Case presentation

We evaluated a 30-year-old female laboratory worker exposed to the dengue virus by needlestick injury while conducting virus filtering. During admission, she showed symptoms of fever, nausea, myalgia, and a characteristic maculopapular rash with elevated aspartate aminotransferase (AST) of 235 IU/L and alanine aminotransferase (ALT) of 269 IU/L. She had been diagnosed by a positive nonstructural protein 1 (NS1) antigen (Ag) rapid test one day prior to symptom onset along with positive immunoglobulin M (IgM) enzyme-linked immunosorbent assay (ELISA) on the ninth day of symptom onset. Reverse transcription polymerase chain reaction (RT-PCR), also conducted on the ninth day, was negative. After proper symptomatic treatment, she recovered without any sequelae. As a result of thorough epidemiologic investigation, it was determined that she had tried to recap the needle during the virus filtering procedure and a subsequent needlestick injury occurred.

Conclusions

In the context of health promotion of laboratory workers, we suggest that the laboratory biosafety manual be revised and reinforced, and related prevention measures be implemented. Furthermore, health authorities and health care providers in Korea should be fully informed of proper dengue fever management.