Endemic and emerging acute virus infections in Indonesia: an overview of the past decade and implications for the future

Experiences of discharge planning practices among Indonesian nurses: A qualitative study

Background

Discharge planning is vital to preventing hospital readmission, and nurses play a key role. The COVID-19 pandemic has posed challenges to hospital services that may persist or recur. Therefore, exploring nurses' experiences with discharge planning practices before and during this pandemic is crucial.

Objective

This study aimed to describe the experiences of discharge planning practices among nurses at an Indonesian tertiary hospital before and during the COVID-19 pandemic.

Methods

A qualitative descriptive study design was used. Telephone interviews were conducted to collect data among ten nurses from March 2019 and continued between December 2020 and August 2021. Content analysis was done for data analysis.

Results

Two main themes emerged: 1) Challenges in discharge planning practices and 2) Perceived discharge planning as a professional responsibility. Implementing the inpatient ward fusion policy as part of the hospital's pandemic response presented greater challenges to nurses in coordinating care and performing discharge planning. Fear of COVID-19 infection, social distancing measures, and using personal protective equipment also affected how nurses delivered discharge education during the pandemic. However, the nurses sensed a greater responsibility to ensure the maintenance of essential components of discharge planning procedures to guarantee the patient's capability to perform self-care at home.

Conclusion

Nurses viewed discharge planning practices as their responsibility and continued them during the pandemic despite facing various challenges. In addition to recognizing the significance of nurses' roles in discharge planning practices and overall patient care, it is crucial to anticipate and address the diverse working patterns and styles among healthcare professionals in unified wards, ensuring effective coordination.

From Archipelago to Pandemic Battleground: Unveiling Indonesia's COVID-19 Crisis

The coronavirus disease 2019 (COVID-19) pandemic has posed unprecedented challenges to countries worldwide, including Indonesia. With its unique archipelagic geography consisting of more than 17,000 thousand islands, Indonesia faces unique complexities in managing the spread of the virus. Based on existing literature, this review article elaborates on key issues that have shaped Indonesia's COVID-19 response. The article begins by examining the early stages of the COVID-19 pandemic in Indonesia, along with the implementation of various preventive measures and the impact of the virus on public health. This article examines how Indonesia's socio-economic factors have generally influenced its healthcare system and further delves into the COVID-19 response strategies implemented by the Indonesian government and public health authorities as well as overall crisis preparedness. It discusses the actions taken to control the spread of the virus, including testing strategies and vaccination efforts. The difficulties encountered in implementing these measures are presented. In conclusion, this review article provides a comprehensive understanding of the COVID-19 crisis in Indonesia, covering facts on multiple dimensions ranging from the timeline of the pandemic to vaccination efforts, epidemiology, socio-economic implications, testing strategies, mobility patterns, public holidays, the impact of working from home, and the utilization of complementary and alternative medicine in addition to the standard of care for COVID-19. The insights gained from this article can complement future strategies for pandemic management and response in Indonesia and other countries facing similar challenges.

Multi-Year Monitoring of the Toxicological Risk of Heavy Metals Related to Fish Consumption by the Population of the Kendari Region (Southeast Sulawesi, Indonesia)

This study measured the concentrations of Hg, As, Ni, Cd, and Pb in six fish species commonly consumed in Kendari. Samples were bought within local markets from 2012 to 2017 at the end of the dry season. Results showed that mercury concentrations fluctuated between years and within species, except in the Caranx sexfasciatus, which showed no significant differences (Kruskall-Wallis, p-value > 0.05, df = 5) and an average concentration of 0.371 ± 0.162 µg g-1 DW. Arsenic was found in high concentrations across species and years and varied widely in C. sexfasciatus, the lowest value being 0.32 ± 0.01 µg g-1 DW in 2012 and the highest was 5.63 ± 1.89 µg g-1 DW in 2017. The highest nickel concentrations were found in 2016 across four of the six species. The fish samples displayed very low cadmium and lead concentrations throughout the study. In addition, the potential human health risk due to fish consumption was assessed. This showed that mercury is the only one of the five metals present in concentrations high enough to individually pose a potential hazard, the only metal likely to be accumulated beyond a safe concentration in Kendari. Chanos chanos never posed a toxicological risk based on the results of this research.

Spatial differentiation and determinants of COVID-19 in Indonesia

Background

The spread of the coronavirus disease 2019 (COVID-19) has increasingly agonized daily lives worldwide. As an archipelagic country, Indonesia has various physical and social environments, which implies that each region has a different response to the pandemic. This study aims to analyze the spatial differentiation of COVID-19 in Indonesia and its interactions with socioenvironmental factors.

Methods

The socioenvironmental factors include seven variables, namely, the internet development index, literacy index, average temperature, urban index, poverty rate, population density (PD) and commuter worker (CW) rate. The multiple linear regression (MLR) and geographically weighted regression (GWR) models are used to analyze the impact of the socioenvironmental factors on COVID-19 cases. COVID-19 data is obtained from the Indonesian Ministry of Health until November 30th 2020.

Results

Results show that the COVID-19 cases in Indonesia are concentrated in Java, which is a densely populated area with high urbanization and industrialization. The other provinces with numerous confirmed COVID-19 cases include South Sulawesi, Bali, and North Sumatra. This study shows that the socioenvironmental factors, simultaneously, influence the increasing of confirmed COVID-19 cases in the 34 provinces of Indonesia. Spatial interactions between the variables in the GWR model are relatively better than those between the variables in the MLR model. The highest spatial tendency is observed outside Java, such as in East Nusa Tenggara, West Nusa Tenggara, and Bali.

Conclusion

Priority for mitigation and outbreak management should be high in areas with high PD, urbanized spaces, and CW.

Epidemiology of cerebral palsy in low- and middle-income countries: preliminary findings from an international multi-centre cerebral palsy register

AIM

To describe the epidemiology of cerebral palsy (CP) in children from low- and middle-income countries (LMICs) using data from the Global Low- and Middle-Income Country CP register (GLM-CPR).

METHOD

The GLM-CPR is a multi-country initiative that combines and compares data from children with CP (<18y) in LMICs. Children with CP are registered after detailed neurodevelopmental assessment by a multidisciplinary medical team using a harmonized protocol. Data are collected on agreed core variables. Descriptive analyses are completed to report findings from participating countries.

RESULTS

Between January 2015 and May 2019, 2664 children were recruited from Bangladesh, Nepal, Indonesia, and Ghana (mean age [SD] at assessment: 7y 8mo [4y 8mo], 95% confidence interval 7y 6mo-7y 11mo; male [n=1615] 60.6%, female [n=1049] 39.4%). Overall, 86.6% children acquired CP prenatally and perinatally (e.g. preterm birth, birth asphyxia, neonatal encephalopathy). Median age at CP diagnosis was 3 years. Moreover, 79.2% children had spastic CP and 73.3% were classified in Gross Motor Function Classification System levels III to V. Notably, 47.3% of children never received rehabilitation services (median age at receiving rehabilitation services was 3y; 12.7% received assistive devices) and 75.6% of school-age children had no access to education.

INTERPRETATION

Population-based data show that the proportion of severe cases of CP is very high in LMICs. Children with CP in LMICs lack access to rehabilitation and educational services and a large proportion of children have potentially preventable risk factors, for example, birth asphyxia and neonatal infections. Delayed diagnosis, severe motor impairments, and lack of rehabilitation in most children call for urgent action to identify preventive opportunities and promote early diagnosis and intervention for children with CP in LMICs. What this paper adds The proportion of severe cases of cerebral palsy (CP) is very high in rural low- and middle-income countries (LMICs). Children with CP in LMICs lack access to rehabilitation and educational services. A large proportion of children with CP in LMICs have potentially preventable risk factors.

Japanese encephalitis in Bali, Indonesia: ecological and socio-cultural perspectives

The increasing number of cases of acute encephalitis syndrome, a key presenting clinical sign of Japanese encephalitis infection in humans, along with increasing laboratory confirmed cases in Bali over recent years have led to the Indonesian government developing a national program of vaccination against Japanese encephalitis virus. In order to inform multidisciplinary management, a review was conducted to assess Japanese encephalitis virus-related cases in humans and animals including their determinants and detection in vectors. Along with published literature, key data from local authorized officers in Bali have been used to convey the recent situation of the disease. Related surveys detected up to 92% of the local children had antibodies against the virus with the annual incidence estimated to be 7.1 per 100,000 children. Additionally, reports on young and adult cases of infection within international travellers infected in Bali were documented with both non-fatal and fatal outcomes. Further seroprevalence surveys detected up to 90% with antibodies to the virus in animal reservoirs. The detection of the virus in certain Culex mosquito species and high levels of seropositivity may be associated with greater risk of the virus transmission to the human population. It was also highlighted that local sociocultural practices for agriculture and livestock were potentially associated with the high density of the vector and the reservoirs, which then may lead to the risk of the disease transmission in the ecology of Bali.

Molecular epidemiology of dengue in North Kalimantan, a province with the highest incidence rates in Indonesia in 2019

OBJECTIVES

Dengue is endemic to Indonesia, a country that has largely varied geographical and demographic conditions across different regions. In 2019, dengue epidemic occurred in North Kalimantan province and recorded as the highest incidence rate in Indonesia. This study aims to investigate the molecular epidemiology of dengue during outbreak in the province and compare the epidemiological characteristics between two cities/towns in North Kalimantan, namely Malinau, an inland town surrounded by a dense rainforest, and Tarakan, an island city.

METHODS

A cross sectional study was conducted between September 2018 and July 2019. Dengue-like illness patients were recruited in hospitals and tested for dengue NS1 and IgG/IgM. Serological prevalence was measured using IgG ELISA, dengue virus (DENV) serotyping was conducted using RT-PCR and Envelope gene sequencing was performed to infer the virus origins and phylogeny. Clinical, demographical, and diagnostics data were also recorded and analyzed.

RESULTS

We recruited 523 patients, 261 from Malinau and 262 from Tarakan. Among them, 349 patients were confirmed dengue. Cases in Malinau had a higher proportion of confirmed dengue (82.0%) compared to those in Tarakan (51.5%). Cases in Malinau were more likely to be dengue hemorrhagic fever with more severe hematological features compared to those in Tarakan. All four DENV serotypes were detected in both cities, the most prevalent serotype being DENV-2. The genetic characteristics of the viruses in the two towns was similar except for DENV-3. No sylvatic DENV was detected as well as alphaviruses and non-dengue flaviviruses during the outbreak.

CONCLUSIONS

The molecular epidemiology of dengue in North Kalimantan revealed the similar virological characteristics but different clinical and demographic aspects in Malinau and Tarakan. The distinct dengue dynamics between different regions of Indonesia is prominent and this knowledge will be important for understanding future patterns of DENV transmission in the region.

Relation between occupants' health problems, demographic and indoor environment subjective evaluations: A cross-sectional questionnaire survey study in Java Island, Indonesia

This study aimed to evaluate the link between health problems, demographic factors, and the indoor environment quality of residents in Indonesia. We conducted a cross-sectional design study through a questionnaire survey with 443 respondents aged between 12 and 81 years. The questionnaire was concerned with previous health problem occurrences associated with thermal discomfort experiences, indoor environments, economic conditions, and basic anthropometric factors. Logistic regression with the odds ratio (OR) was applied to evaluate the tendency of different respondent groups to suffer from certain health problems, when compared to reference groups. Furthermore, structural equation modelling (SEM) was used to incorporate certain factors (economic conditions, thermal discomfort experiences, and perceived indoor environments) into a single model to understand their direct and indirect effects on health conditions. The results indicate that economic conditions are the most significantly associated with health problems. Furthermore, we found that the low-income group was the most vulnerable to health problems, including coughing, puking, diarrhoea, odynophagia, headaches, fatigue, rheumatism, fidgeting, skin rashes, muscle cramps, and insomnia (OR: 1.94-6.04, p <0.05). Additionally, the SEM suggested that the respondents' economic conditions and thermal discomfort experiences had significant direct effects on their health problems with standardized estimates of -0.29 and 0.55, respectively. Additionally, perceived indoor environment quality, which is possible to cause thermal discomfort experience, indirectly affect health problems. These findings contribute an insightful and intuitive knowledge base which can aid health assessments associated with demographic and physical environments in developing sustainable and healthy environment strategies for the future.

Comparative cytokine profiling identifies common and unique serum cytokine responses in acute chikungunya and dengue virus infection

Background

Infection by chikungunya (CHIKV) and dengue virus (DENV) can cause a wide spectrum of clinical features, many of which are undifferentiated. Cytokines, which broadly also include chemokines and growth factors, have been shown to play a role in protective immunity as well as DENV and CHIKV pathogenesis. However, differences in cytokine response to both viruses remain poorly understood, especially in patients from countries where both viruses are endemic. Our study is therefore aimed to provide a comparative profiling of cytokine response induced by acute DENV and CHIKV infections in patients with similar disease stages and in experimental in vitro infections.

Methods

By using multiplex immunoassay, we compared host cytokine profiles between acute CHIKV and DENV infections by analysing serum cytokine levels of IL-1α, IL-4, IL-5, IL-8, IL-13, RANTES, MCP-3, eotaxin, PDGF-AB/BB, and FGF-2 from the sera of acute chikungunya and dengue fever patients. We further investigated the cytokine profile responses using experimental in vitro CHIKV and DENV infections of peripheral blood mononuclear cells (PBMCs).

Results

We found that both CHIKV and DENV-infected patients had an upregulated level of IL-8 and IL-4, with the highest IL-4 level observed in DENV-2 infected patients. Higher IL-8 level was also correlated with lower platelet count in dengue patients. IL-13 and MCP-3 downregulation was observed only in chikungunya patients, while conversely PDGF-AB/BB and FGF-2 downregulation was unique in dengue patients. Age-associated differential expression of IL-13, MCP-3, and IL-5 was also observed, while distinct kinetics of IL-4, IL-8, and FGF-2 expression between CHIKV and DENV-infected patients were identified. Furthermore, the unique pattern of IL-8, IL-13 and MCP-3, but not IL-4 expression was also recapitulated using experimental in vitro infection in PBMCs.

Conclusions

Taken together, our study identified common cytokine response profile characterized by upregulation of IL-8 and IL-4 between CHIKV and DENV infection. Downregulation of IL-13 and MCP-3 was identified as a unique cytokine response profile of acute CHIKV infection, while distinct downregulation of PDGF-AB/BB and FGF-2 characterized the response from acute DENV infection. Our study provides an important overview of the host cytokine responses between CHIKV and DENV infection, which is important to further understand the mechanism and pathology of these diseases.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-021-06339-6.

Spatiotemporal Analysis of COVID-19 Spread with Emerging Hotspot Analysis and Space–Time Cube Models in East Java, Indonesia

In this research, we analyzed COVID-19 distribution patterns based on hotspots and space–time cubes (STC) in East Java, Indonesia. The data were collected based on the East Java COVID-19 Radar report results from a four-month period, namely March, April, May, and June 2020. Hour, day, and date information were used as the basis of the analysis. We used two spatial analysis models: the emerging hotspot analysis and STC. Both techniques allow us to identify the hotspot cluster temporally. Three-dimensional visualizations can be used to determine the direction of spread of COVID-19 hotspots. The results showed that the spread of COVID-19 throughout East Java was centered in Surabaya, then mostly spread towards suburban areas and other cities. An emerging hotspot analysis was carried out to identify the patterns of COVID-19 hotspots in each bin. Both cities featured oscillating patterns and sporadic hotspots that accumulated over four months. This pattern indicates that newly infected patients always follow the recovery of previous COVID-19 patients and that the increase in the number of positive patients is higher when compared to patients who recover. The monthly hotspot analysis results yielded detailed COVID-19 spatiotemporal information and facilitated more in-depth analysis of events and policies in each location/time bin. The COVID-19 hotspot pattern in East Java, visually speaking, has an amoeba-like pattern. Many positive cases tend to be close to the city, in places with high road density, near trade and business facilities, financial storage, transportation, entertainment, and food venues. Determining the spatial and temporal resolution for the STC model is crucial because it affects the level of detail for the information of endemic disease distribution and is important for the emerging hotspot analysis results. We believe that similar research is still rare in Indonesia, although it has been done elsewhere, in different contexts and focuses.

Epidemiology of cerebral palsy in Sumba Island, Indonesia

AIM

To define the epidemiology, clinical characteristics, and rehabilitation status of children with cerebral palsy (CP) in Sumba Island, Indonesia.

METHOD

A community-based key informant method survey among children (aged <18y) with CP was conducted between March and August 2017. Children with suspected CP underwent detailed neurodevelopmental assessment by a multidisciplinary medical team. Socio-demographic characteristics, aetiology, motor type, motor severity, associated impairments, educational, and rehabilitation status were documented.

RESULTS

There were 130 children with clinically confirmed CP. The mean age at assessment was 8 years 11 months and 43.8% (n=57) of the children were female. The mean age at CP diagnosis was 6 years 5 months. Of these children, 46.9% (n=61) had post-neonatally acquired CP, most frequently because of vaccine-preventable infectious encephalopathy (73.8%, n=45). In total, 80.8% (n=105) had a predominantly spastic motor type of CP and 83.8% (n=109) were classified in Gross Motor Functional Classification System levels III to V. A total of 77.7% (n=101) had at least one associated impairment (speech 77.5%, intellectual 29.2%, visual 13.8%, hearing 20.0%, and epilepsy 13.5%). And 66.2% (n=86) had never received rehabilitation services.

INTERPRETATION

Post-neonatally acquired CP was common in this setting. Addressing preventable post-neonatally acquired risk factors for CP should be a public health priority. Earlier identification and diagnosis of CP would also provide new opportunities for early intervention and targeted rehabilitation services.

Distinct Dengue Disease Epidemiology, Clinical, and Diagnosis Features in Western, Central, and Eastern Regions of Indonesia, 2017-2019

The people of Indonesia have been afflicted by dengue, a mosquito-borne viral disease, for over 5 decades. The country is the world's largest archipelago with diverse geographic, climatic, and demographic conditions that may impact the dynamics of disease transmissions. A dengue epidemiology study was launched by us to compare and understand the dynamics of dengue and other arboviral diseases in three cities representing western, central, and eastern Indonesia, namely, Batam, Banjarmasin, and Ambon, respectively. A total of 732 febrile patients were recruited with dengue-like illness during September 2017-2019 and an analysis of their demographic, clinical, and virological features was performed. The seasonal patterns of dengue-like illness were found to be different in the three regions. Among all patients, 271 (37.0%) were virologically confirmed dengue, while 152 (20.8%) patients were diagnosed with probable dengue, giving a total number of 423 (57.8%) dengue patients. Patients' age and clinical manifestations also differed between cities. Mostly, mild dengue fever was observed in Batam, while more severe cases were prominent in Ambon. While all dengue virus (DENV) serotypes were detected, distinct serotypes dominated in different locations: DENV-1 in Batam and Ambon, and DENV-3 in Banjarmasin. We also assessed the diagnostic features in the study sites, which revealed different patterns of diagnostic agreements, particularly in Ambon. To detect the possibility of infection with other arboviruses, further testing on 461 DENV RT-PCR-negative samples was performed using pan-flavivirus and -alphavirus RT-PCRs; however, only one chikungunya infection was detected in Ambon. A diverse dengue epidemiology in western, central, and eastern Indonesia was observed, which is likely to be influenced by local geographic, climatic, and demographic conditions, as well as differences in the quality of healthcare providers and facilities. Our study adds a new understanding on dengue epidemiology in Indonesia.

Point-of-care thrombocyte function testing using multiple-electrode aggregometry in dengue patients: an explorative study

Background

Dengue virus (DENV) causes the hospitalisation of an estimated 500,000 people every year. Outbreaks can severely stress healthcare systems, especially in rural settings. It is difficult to discriminate patients who need to be hospitalized from those that do not. Earlier work identified thrombocyte count and subsequent function as a promising prognostic marker of DENV severity. Herein, we investigated the potential of quantitative thrombocyte function tests in those admitted in the very early phase of acute DENV infections, using Multiplate™ multiple-electrode aggregometry to explore its potential in triage.

Methods

In this prospective cohort study all patients aged ≥13 admitted to Universitas Airlangga Hospital in Surabaya, Indonesia with a fever (≥38 °C) between 25 January and 1 August 2018 and with a clinical suspicion of DENV, were eligible for inclusion. Exclusion criteria were a thrombocyte count below 100 × 109/L and the use of any medication with a known anticoagulant effect, nonsteroidal anti-inflammatory drugs and acetyl salicylic acid. Clinical data was collected and blood was taken on admission, day 1 and day 7. Samples were tested for acute DENV, using Panbio NS1 ELISA. Platelet aggregation using ADP-, TRAP- and COL-test were presented as Area Under the aggregation Curve (AUC). Significance was tested between DENV+, probably DENV, fever of another origin, and healthy controls (HC).

Results

A total of 59 patients (DENV+ n = 10, DENV probable n = 25, fever other origin n = 24) and 20 HC were included. We found a significantly lower thrombocyte aggregation in the DENV+ group, compared with both HCs and the fever of another origin group (p < .001). Low ADP AUC values on baseline correlated to a longer hospital stay in DENV+ and probable DENV cases.

Conclusion

Thrombocyte aggregation induced by Adenosine diphosphate, Collagen and Thrombin receptor activating peptide-6 is impaired in human DENV cases, compared with healthy controls and other causes of fever. This explorative study provides insights to thrombocyte function in DENV patients and could potentially serve as a future marker in DENV disease.

Pathogenic viruses: Molecular detection and characterization

Pathogenic viruses are viruses that can infect and replicate within human cells and cause diseases. The continuous emergence and re-emergence of pathogenic viruses has become a major threat to public health. Whenever pathogenic viruses emerge, their rapid detection is critical to enable implementation of specific control measures and the limitation of virus spread. Further molecular characterization to better understand these viruses is required for the development of diagnostic tests and countermeasures. Advances in molecular biology techniques have revolutionized the procedures for detection and characterization of pathogenic viruses. The development of PCR-based techniques together with DNA sequencing technology, have provided highly sensitive and specific methods to determine virus circulation. Pathogenic viruses potentially having global catastrophic consequences may emerge in regions where capacity for their detection and characterization is limited. Development of a local capacity to rapidly identify new viruses is therefore critical. This article reviews the molecular biology of pathogenic viruses and the basic principles of molecular techniques commonly used for their detection and characterization. The principles of good laboratory practices for handling pathogenic viruses are also discussed. This review aims at providing researchers and laboratory personnel with an overview of the molecular biology of pathogenic viruses and the principles of molecular techniques and good laboratory practices commonly implemented for their detection and characterization.

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The continous emergence and re-emergence of pathogenic viruses has become a major threat to public health.

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PCR-based techniques together with DNA sequencing technology have provided highly sensitive and specific methods to determine virus circulation.

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Southeast Asia is considered to be vulnerable to potential outbreaks of pathogenic viruses. A number of pathogenic viruses have been reported to circulate in this region. The 2019 novel coronavirus has also been identified in Southeast Asia.

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Development of local capacity to rapidly identify new viruses is very important.

Zika Outbreak Emergency Preparedness and Response of Malaysian Private Healthcare Professionals: Are They Ready?

Zika virus has been declared as a public health emergency of international concern. The Center for Disease Control and Prevention has issued guidelines reminding healthcare workers about the importance of taking steps to prevent the spread of Zika virus, how to test and isolate patients suspected of carrying the Zika virus, and how to protect themselves from infection. Therefore, it is of utmost importance for healthcare professionals to be fully aware of Zika virus preparedness, and response measures should an outbreak occur in Malaysia in order to quickly and efficiently contain the outbreak, ensure the safety of individual or healthcare personnel safety, as well as to prevent further spreading of the disease. This research aims to show how prepared Malaysian healthcare professionals are against Zika virus and how well can they respond during an outbreak. In total, 504 healthcare professionals (128 general practitioners, 215 community pharmacists, 161 nurses) from private health clinics were the target population of the four states of Malaysia where Zika cases suspected. The sample size of each category was calculated by using a formula for estimating the population proportion. An additional 10% of the calculated sample size was added to compensate the non-response rate. The Center For Disease Control and Prevention and World Health Organisation provided a checklist to assess how prepared healthcare professionals are for an Zika outbreak. This checklist was modified to a questionnaire in order to assess health care professionals’ preparedness and response to the Zika outbreak. Community pharmacists are still lacking in their preparedness and perceived response to the Zika outbreak compared to the general practitioners in the private sector. Hence community pharmacists should attend training given by the Ministry of Health Malaysia as a continuing education, which may help them to respond during a Zika outbreak.

Chikungunya virus infection in Indonesia: a systematic review and evolutionary analysis

Background

Despite the high number of chikungunya cases in Indonesia in recent years, comprehensive epidemiological data are lacking. The systematic review was undertaken to provide data on incidence, the seroprevalence of anti-Chikungunya virus (CHIKV) IgM and IgG antibodies, mortality, the genotypes of circulating CHIKV and travel-related cases of chikungunya in the country. In addition, a phylogenetic and evolutionary analysis of Indonesian CHIKV was conducted.

Methods

A systematic review was conducted to identify eligible studies from EMBASE, MEDLINE, PubMed and Web of Science as of October 16th 2017. Studies describing the incidence, seroprevalence of IgM and IgG, mortality, genotypes and travel-associated chikungunya were systematically reviewed. The maximum likelihood phylogenetic and evolutionary rate was estimated using Randomized Axelerated Maximum Likelihood (RAxML), and the Bayesian Markov chain Monte Carlo (MCMC) method identified the Time to Most Recent Common Ancestors (TMRCA) of Indonesian CHIKV. The systematic review was registered in the PROSPERO database (CRD42017078205).

Results

Chikungunya incidence ranged between 0.16-36.2 cases per 100,000 person-year. Overall, the median seroprevalence of anti-CHIKV IgM antibodies in both outbreak and non-outbreak scenarios was 13.3% (17.7 and 7.3% for outbreak and non-outbreak events, respectively). The median seroprevalence of IgG antibodies in both outbreak and non-outbreak settings was 18.5% (range 0.0–73.1%). There were 130 Indonesian CHIKV sequences available, of which 120 (92.3%) were of the Asian genotype and 10 (7.7%) belonged to the East/Central/South African (ECSA) genotype. The ECSA genotype was first isolated in Indonesia in 2008 and was continually sampled until 2011. All ECSA viruses sampled in Indonesia appear to be closely related to viruses that caused massive outbreaks in Southeast Asia countries during the same period. Massive nationwide chikungunya outbreaks in Indonesia were reported during 2009–2010 with a total of 137,655 cases. Our spatio-temporal, phylogenetic and evolutionary data suggest that these outbreaks were likely associated with the introduction of the ECSA genotype of CHIKV to Indonesia.

Conclusions

Although no deaths have been recorded, the seroprevalence of anti-CHIKV IgM and IgG in the Indonesian population have been relatively high in recent years following re-emergence in early 2001. There is sufficient evidence to suggest that the introduction of ECSA into Indonesia was likely associated with massive chikungunya outbreaks during 2009–2010.

Electronic supplementary material

The online version of this article (10.1186/s12879-019-3857-y) contains supplementary material, which is available to authorized users.

Dengue infection in international travellers visiting Bali, Indonesia

BACKGROUND

Dengue, an acute febrile illness caused by infection with dengue virus (DENV), is endemic in Bali, Indonesia. As one of the world's most popular tourist destinations, Bali is regularly visited by domestic and international travellers, who are prone to infection by endemic pathogens, including DENV. Currently, limited data are available on the characteristics of dengue in travellers visiting Bali. Information on the epidemiology and virological aspects of dengue in these tourists is important to gain a better understanding of the dengue disease in international travellers.

METHODS

We performed a prospective cross-sectional dengue study involving foreign travellers visiting Bali, Indonesia in the period of 2015-17. Patients presenting at Kasih Ibu Hospital with fever and clinical symptoms of dengue were asked to participate in the study. Clinical and laboratory assessments were performed and sera were collected for molecular analysis, which included DENV serotyping, genome sequencing and phylogenetic analysis.

RESULTS

Among the 201 patients recruited, dengue was confirmed in 133 (66.2%) of them, based on detection of NS1 antigen and/or viral RNA. Of these, 115 (86.5%) manifested dengue fever (DF) and 18 (13.5%) dengue haemorrhagic fever (DHF). The temporal predominance of infecting DENV serotype was DENV-2 (48.7%), followed by DENV-3 (36.1%), DENV-1 (9.2%) and DENV-4 (3.4%). Phylogenetic analysis of DENV based on envelope gene sequences revealed that the source of DENVs was local endemic viruses.

CONCLUSION

Our study confirms that dengue is one of the causes of fever in travellers visiting Bali. Although it is a cause of significant morbidity, the majority of patients only experienced mild DF, with only a small proportion developing DHF. We revealed that DENVs isolated were autochthonous. Accurate diagnosis, preventive measures and continuous disease surveillance will be useful for better management of dengue infection in travellers.