Endemic Dengue Research Articles

Co-infection of COVID-19 and dengue: a case report

COVID-19 has now spread to most countries, causing a global pandemic. As the COVID-19 pandemic is still ongoing, some part of the world region with tropical climate is facing a dual burden of infection with the presence of concurrent endemic infectious disease. This endemic dengue infection and the COVID-19 pandemic may turn out into a fatal and hazardous combination. In addition, dengue and COVID-19 possess clinical and laboratory features that are sometimes difficult to differentiate. The possibility of COVID-19 and dengue co-infection has also been a noticeable issue. We present a case of 19-year-old male with COVID-19 and dengue co-infection admitted at Wangaya Regional Hospital Denpasar, Bali. Co-infection of COVID-19 and dengue requires special attention from all health care workers in dengue-endemic countries in order to avoid diagnostic delays and improve clinical outcome. It is also necessary to conduct further research which explores the potential of co-infection between coronavirus and arbovirus.

Assessment of the global circulation and endemicity of dengue.

Dengue is a significant public health issue, affecting hundreds of millions of people worldwide. As it is spreading from tropical and subtropical zones, some regions previously recognised as non-endemic are at risk of becoming endemic. However, the global circulation of dengue is not fully understood and quantitative measurements of endemicity levels are lacking, posing an obstacle in the precise control of dengue spread. In this study, a sequence-based pipeline was designed based on random sampling to study the transmission of dengue. The limited intercontinental transmission was identified, while regional circulation of dengue was quantified in terms of importation, local circulation and exportation. Additionally, hypo- and hyper-endemic regions were identified using a new metric, with the former characterised by low local circulation and increased importation, whereas the latter by high local circulation and reduced importation. In this study, the global circulation pattern of dengue was examined and a sequence-based endemicity measurement was proposed, which will be helpful for future surveillance and targeted control of dengue.

Voltage-Gated Sodium Channel (Vgsc) Mutation-Based Pyrethroid Resistance in Aedes aegypti Populations of Three Endemic Dengue Risk Areas of Sri Lanka.

Background Pyrethroid insecticides are widely used in many countries for chemical-based control of Ae. aegypti. Regardless of their efficacy, the constant use of insecticides has induced insecticide resistance mechanisms, such as knockdown resistance (kdr) in mosquitoes. Sri Lankan Vector Controlling Entities (VCE) have been using a variety of pyrethroid insecticides as the primary approach for dengue control. However, development of any resistance among the Aedes mosquitoes has been limitedly studied in the country. Therefore, the current study was conducted to evaluate the prevalence of F1534C, V1016G, and S989P mutations among Ae. aegypti mosquito populations in three dengue endemic high-risk regions of Sri Lanka. Methodology. Immature (both pupae and larvae) stages of Ae. aegypti mosquitoes were collected from Colombo, Gampaha, and Kandy districts of Sri Lanka from February 2018 to December 2019. Polymerase Chain Reaction- (PCR-) based assay for molecular genotyping of mutations was performed to identify the prevalence of kdr mutations in collected Ae. aegypti populations, separately. The frequencies of the resistant and susceptible kdr alleles were determined by using the Hardy–Weinberg equilibrium. Results The Ae. aegypti populations from Colombo, Gampaha, and Kandy districts showed 46%, 42%, and 22% of F1534C mutation allele frequencies, along with 15%, 12%, and 6% of V1016G mutation allele frequencies, respectively. The mutation allele frequencies of S989 in Colombo, Gampaha, and Kandy districts were 9.5%, 8.5%, and 4.5%, respectively. The wild-type (PP) genotype remained predominant within all the three districts, whereas the homogenous (QQ) mutation genotype occurred only in minority. The abundance of Q allele frequency in Ae. aegypti mosquitoes was relatively higher for all the three mutations in Colombo. Conclusions The findings clearly indicate that long-term insecticide applications and multiple use of pyrethroids have led to the acquisition of kdr mutations, leading to the development of insecticide resistance among local Ae. aegypti populations, especially in the Colombo and Gampaha districts. Therefore, evaluation of the prevalence levels of these kdr mutations highlights the necessity for shifting towards novel vector control strategies.

Global patterns of aegyptism without arbovirus.

The world's most important mosquito vector of viruses, Aedes aegypti, is found around the world in tropical, subtropical and even some temperate locations. While climate change may limit populations of Ae. aegypti in some regions, increasing temperatures will likely expand its territory thus increasing risk of human exposure to arboviruses in places like Europe, Northern Australia and North America, among many others. Most studies of Ae. aegypti biology and virus transmission focus on locations with high endemicity or severe outbreaks of human amplified urban arboviruses, such as dengue, Zika, and chikungunya viruses, but rarely on areas at the margins of endemicity. The objective in this study is to explore previously published global patterns in the environmental suitability for Ae. aegypti and dengue virus to reveal deviations in the probability of the vector and human disease occurring. We developed a map showing one end of the gradient being higher suitability of Ae. aegypti with low suitability of dengue and the other end of the spectrum being equal and higher environmental suitability for both Ae. aegypti and dengue. The regions of the world with Ae. aegypti environmental suitability and no endemic dengue transmission exhibits a phenomenon we term 'aegyptism without arbovirus'. We then tested what environmental and socioeconomic variables influence this deviation map revealing a significant association with human population density, suggesting that locations with lower human population density were more likely to have a higher probability of aegyptism without arbovirus. Characterizing regions of the world with established populations of Ae. aegypti but little to no autochthonous transmission of human-amplified arboviruses is an important step in understanding and achieving aegyptism without arbovirus.

Microbial Diversity of Adult Aedes aegypti and Water Collected from Different Mosquito Aquatic Habitats in Puerto Rico.

Mosquitoes, the major vectors of viruses like dengue, are naturally host to diverse microorganisms, which play an important role in their development, fecundity, immunity, and vector competence. The composition of their microbiota is strongly influenced by the environment, particularly their aquatic larval habitat. In this study, we used 2×300 bp 16s Illumina sequencing to compare the microbial profiles of emerging adult Aedes aegypti mosquitoes and the water collected from common types of aquatic habitat containers in Puerto Rico, which has endemic dengue transmission. We sequenced 141 mosquito and 46 water samples collected from plastic containers, septic tanks, discarded tires, underground trash cans, tree holes, or water meters. We identified 9 bacterial genera that were highly prevalent in the mosquito microbiome, and 77 for the microbiome of the aquatic habitat. The most abundant mosquito-associated bacterial OTUs were from the families Burkholderiaceae, Pseudomonadaceae, Comamonadaceae, and Xanthomonadaceae. Microbial profiles varied greatly between mosquitoes, and there were few major differences explained by container type; however, the microbiome of mosquitoes from plastic containers was more diverse and contained more unique taxa than the other groups. Container water was significantly more diverse than mosquitoes, and our data suggest that mosquitoes filter out many bacteria, with Alphaproteobacteria in particular being far more abundant in water. These findings provide novel insight into the microbiome of mosquitoes in the region and provide a platform to improve our understanding of the fundamental mosquito-microbe interactions.

Epidemiology of dengue virus infections in Nepal, 2006\u20132019

BackgroundDengue is one of the newest emerging diseases in Nepal with increasing burden and geographic spread over the years. The main objective of this study was to explore the epidemiological patterns of dengue since its first outbreak (2006) to 2019 in Nepal.MethodsThis study is a retrospective analysis that covers the last 14 years (2006–2019) of reported dengue cases from Epidemiology Diseases Control Division (EDCD), Ministry of Health and Population, Government of Nepal. Reported cases were plotted over time and maps of reported case incidence were generated (from 2016 through 2019). An ecological analysis of environmental predictors of case incidence was conducted using negative binomial regression.ResultsWhile endemic dengue has been reported in Nepal since 2006, the case load has increased over time and in 2019 a total of 17 992 dengue cases were reported from 68 districts (from all seven provinces). Compared to the case incidence in 2016, incidence was approximately five times higher in 2018 [incidence rate ratio (IRR): 4.8; 95% confidence interval (CI) 1.5–15.3] and over 140 times higher in 2019 (IRR: 141.6; 95% CI 45.8–438.4). A one standard deviation increase in elevation was associated with a 90% decrease in reported case incidence (IRR: 0.10; 95% CI 0.01–0.20). However, the association between elevation and reported cases varied across the years. In 2018 there was a cluster of cases reported from high elevation Kaski District of Gandaki Province. Our results suggest that dengue infections are increasing in magnitude and expanding out of the lowland areas to higher elevations over time.ConclusionsThere is a high risk of dengue outbreak in the lowland Terai region, with increasing spread towards the mid-mountains and beyond as seen over the last 14 years. Urgent measures are required to increase the availability of diagnostics and resources to mitigate future dengue epidemics.

Spatial Distribution of Dengue Hemorrhagic Fever (DHF) Casesin Sragen

Background: Dengue Hemorrhagic Fever (DHF) had still become a health problem that often occurred and not least caused death for Indonesia especially in Sragen, Central Java. Distribution of DHF cases in an area could be described using Spatial analysis with Geographic Information Systems (GIS). Objective: This study aimed to provide spatial distribution of Dengue Hemorrhagic Fever cases and regional endemicity of DHF in Sragen during 2016-2018 using Geographic Information Systems. Method: Descriptive research design with Cross-Sectional approach using GIS was used to get the description of spatial distribution of dengue and the region endemicity of dengue in Sragen. The sample used was Saturated Sample which was secondary data about the incidence of DHF from District Health Office of Sragen from 2016 to 2018 totaling 1,349 cases. The subjects consisted of geographical areas which consisted of 20 subdistricts with DHF case. The collected data were analyzed descriptively by displaying a frequency distribution table and description of spatial distribution using Geographic Information System. Results: The results showed that the spatial distribution of DHF was spread randomly in all districts in Sragen. The average incidence rate (IR) of DHF during the last 3 years in Sragen was > 50 / 100,000 population. Spatial description showed that 58 villages out of 208 villages in Sragen were DFH endemic areas and generally all subdistricts in Sragen were endemic areas of DHF. Conclusion: Spatial description of DHF in Sragen showed that all subdistricts in Sragen were endemic areas for DHF.

Plant sugar feeding patterns of wild-caught Aedes aegypti from dengue endemic and non-endemic areas of Kenya.

A fundamental understanding of plant sugar feeding behaviour in vector populations can lead to the development of ecologically effective vector monitoring and control strategies. Despite previous studies on mosquito-plant interactions, relatively few have been conducted on the dengue vector Aedes aegypti (Diptera: Culicidae). The authors studied Ae. aegypti-plant interactions at two sites of varying dengue endemicity in Kenya: Kilifi (endemic) and Isiolo (non-endemic). Using chemical and molecular assays [DNA barcoding targeting the chloroplast ribulose-1,5 bisphosphate carboxylase/oxygenase large chain (rbcL) gene], the authors show that at the two sites plant feeding in this mosquito species: (a) varies by sex and season; (b) results in the acquisition of diverse sugars, and (c) is associated with diverse host plants in the families Fabaceae, Malvaceae, Poaceae and Rosaceae. These results reveal insights into the plant sugar feeding patterns of wild-caught Ae. aegypti and provide a baseline for future studies on the olfactory basis for host plant attraction for the development of vector monitoring and control tools.

PENGARUH PEMBERIAN METIL PREDNISOLON INJEKSI TERHADAP

Methyl Prednisolone Injection is a type of corticosteroid drug with the works being categorized adrenokortikoid, anti-inflammatory and immunosuppressant . The purpose of this study was to determine the effect of Methyl prednisolone injection against dengue patient's recovery. This reseach was conducted in February in which the peak of endemic dengue. This reseach uses posttest design with the method of data collection is done by observation of secondary data, that is Methyl Prednisolone therapy injection of the patient's medical record and performed with the processing and tabulation system diagram and analysis using SPSS. From the 13 dengue patients were sampled study concluded that administration of Methyl Prednisolone injection affect total thrombosis and not affect temperature body of patient's recovery.Keywords : Methyl Prednisolone Injection, Total thrombosis, Temperature body, Dengue Patient’s

Prevalence and transmission potential of Wolbachia in Aedes albopictus population circulating in endemic coastal districts of Odisha, India.

Wolbachia, known for its reproductive manipulation capabilities in insects, are being implemented to control dengue and chikungunya. To understand Wolbachia biology and its utility as a bio-control for vector mosquito's populations, we investigated its dissemination pattern in field in collected Ae. albopictus along with its maternal transmission efficacy over generations in regions of endemic dengue (DENV) transmission. Field collected Ae. albopictus were subjected to PCR for Wolbachia screening. Overall mean Wolbachia infection frequency in Ae. albopictus was found out to be 87.3% wherein a trend was observed in the pattern of maternal transmission across generations. χ2 for trend revealed a significant variation between Wolbachia infections and non-infections in Ae. albopictus generations. Linear regression analysis revealed the involvement of a strong negative correlation, implying that overall Wolbachia infection tends to decrease in places with high dengue cases.The reduction in Wolbachia infection frequency may be attributed to several environmental factors with the probability of being the cause for endemicity of dengue in the studied areas.This study reports on the transmission efficacy of naturally occurring Wolbachia in successive generations of Ae. albopictus and its correlation with dengue cases in clusters of Odisha, India. Studying the transmission trend of Wolbachia along with transovarial transmission of DENV might be indicative towards the interplay of Wolbachia infection in presence/absence of DENV.

Frequency of transovarial transmission of dengue virus in Aedes aegypti mosquitoes in endemic areas of dengue hemorrhagic fever in Ceper District, Klaten Regency, Central Java Province, Indonesia

Klaten Regency is an area in Central Java Province with a high rate of endemic dengue hemorrhagic fever. This study aims to demonstrate a correlation between transovarial transmission and the incidence of dengue haemorrhagic fever in Ceper District, Klaten Regency. Aedes larvae and pupae were collected from January 2019 to March 2019 from various containers, using gamadotic and dipper tools, in Ngawonggo, Kajen, and Meger villages, which have high, medium, and low numbers of dengue cases, respectively. The larvae and pupae obtained were reared into adults. The presence of dengue virus in head squashes of 1-week-old female Ae. aegypti was identified based on an immunocytochemical assay using DSSE10 monoclonal antibody, made at Universitas Gadjah Mada as a primary antibody. The frequency of transovarial transmission of dengue virus (TIR) in Ae. aegypti in the three villages was 35.7%. The highest frequency occurred in Ngawonggo Village, at 40 %, and the lowest in Meger Village, at 28%, while the frequency in Kajen Village was 36.9 %. This study proves that there is a strong correlation (r = 0.99664) between transovarial transmission and the incidence of dengue hemorrhagic fever in Ceper District, Klaten Regency, Central Java.

Identification of Primary Container of Aedes Mosquitoes Breeding Site in Urban Region of Dengue Endemic Area, Purwokerto Indonesia

Dengue prevention and control more reliant on reducing its vector, Aedes sp. mosquitoes by mosquito breeding nest eradication method. Therefore, identification of the primary container of the Aedes sp. breeding site particularly in the urban region of dengue-endemic area is a crucial effort to conduct an effective dengue prevention program. This research aimed to identify the primary container of the Aedes sp. breeding site in the urban region of the dengue-endemic area. This is a descriptive cross-sectional study, located in an urban region of dengue-endemic area within Banyumas Regency of Central Java Indonesia. A total of 300 houses in three urban areas were observed in urban areas of Purwokerto namely Arcawinangun, Purwanegara, and Karangpucung (100 houses each area). A total of 1504 water-holding containers were observed. All container was observed and recorded the type, color, lid condition, position, and the presence of mosquito larvae. The analysis was conducted by calculating the percentage of types, color, lid condition, and position of the container also the presence of mosquito larvae. The result of this study highlighted that flower pots and bathtubs were the primary types of containers with Aedes sp. larvae in the urban area. The characteristics of larvae-positive containers mostly open, bright, and located indoor position. Dengue prevention efforts by targeting the primary types of containers for mosquito breeding are expected to reduce the adult mosquito population.

Evolution and epidemiologic dynamics of dengue virus in Nicaragua during the emergence of chikungunya and Zika viruses.

Arthropod-borne viruses (arboviruses) comprise a significant and ongoing threat to human health, infecting hundreds of millions annually. Three such arboviruses include circumtropical dengue, Zika, and chikungunya viruses, exhibiting continuous emergence primarily via Aedes mosquito vectors. Nicaragua has experienced endemic dengue virus (DENV) transmission involving multiple serotypes since 1985, with chikungunya virus (CHIKV) reported in 2014-2015, followed by Zika virus (ZIKV) first reported in 2016. In order to identify patterns of genetic variation and selection pressures shaping the evolution of co-circulating DENV serotypes in light of the arrival of CHIKV and ZIKV, we employed whole-genome sequencing on an Illumina MiSeq platform of random-amplified total RNA libraries to characterize 42 DENV low-passage isolates, derived from viremic patients in Nicaragua between 2013 and 2016. Our approach also revealed clinically undetected co-infections with CHIKV. Of the three DENV serotypes (1, 2, and 3) co-circulating during our study, we uncovered distinct patterns of evolution using comparative phylogenetic inference. DENV-1 genetic variation was structured into two distinct co-circulating lineages with no evidence of positive selection in the origins of either lineage, suggesting they are equally fit. In contrast, the evolutionary history of DENV-2 was marked by positive selection, and a unique, divergent lineage correlated with high epidemic potential emerged in 2015 to drive an outbreak in 2016. DENV-3 genetic variation remained unstructured into lineages throughout the period of study. Thus, this study reveals insights into evolutionary and epidemiologic trends exhibited during the circulation of multiple arboviruses in Nicaragua.

COVID-19 and/with dengue infection: A curse in an overburdened healthcare system.

While the world battles to wrestle with the impact of the COVID-19 pandemic, regions with endemic dengue fever are confronting the possibility of a double pandemic that could completely overpower health care services administrations. Simultaneous outbreaks of dengue and COVID-19, as well as probable cases of overlapping infections, have already started in Latin America and certain Asian countries. There, the healthcare framework is already overburdened and such a deadly duo may completely overwhelm hospital emergency services quite apart from a country's economy. Precise epidemiological and contact history-taking joined with due attention to false-positive dengue serology and the chance of co-infections are key devices for frontline doctors to overcome this seemingly insurmountable challenge.

Ovitrap Surveillance of Aedes aegypti and Aedes albopictus in Dengue Endemic Areas in Keramat and Shah Alam, Selangor in 2016

Introduction: Entomological surveillance is crucial to determine the abundance of dengue vector and to evaluate breeding areas of Aedes aegypti and Aedes albopictus. The objective of this study is to determine the distribution and breeding preference for both Ae. aegypti and Ae. albopictus in dengue endemic areas. Materials and Methods: Ovitraps surveillance was conducted in two dengue endemic areas; AU2, Keramat and Seksyen 7, Shah Alam, Selangor. A minimum number of 100 ovitraps were deployed for 5 days in the study sites. Samples collected were brought back to the lab and all larvae recovered were identified to species level. Results: The ovitap index (OI) in both localities exceeded the transmission threshold of 10% with the OI recorded ranged from 42.3-79.8% in AU2, Keramat and 16.7-42.9% in Seksyen 7, Shah Alam. Ae. albopictus was the dominant species in AU2 Keramat with the highest ratio Ae. aegypti to Ae. albopictus recorded was 1.00:22.79. Nonetheless, in Seksyen 7, Shah Alam the difference in Ae. aegypti to Ae. albopictus ratio is not really prominent with 1.00:3.61 for ovitraps deployed outdoor and 3.40:1.00 for ovitraps set indoor. It was determined that single infestation of either Ae. aegypti or Ae. albopictus is more frequent for ovitraps deployed indoor and/or outdoor, respectively. It was also determined that mixed infestations were found in this study indicating that both species can oviposit in the same container. Conclusion: This study indicates that OI is still above transmission threshold in both study sites. While Ae. aegypti and Ae. albopictus remain as a dominant indoor and outdoor breeder, respectively, mixed breeding of Aedes species in a same container was also observed.

Predicting dengue outbreaks at neighbourhood level using human mobility in urban areas.

Dengue is a vector-borne disease transmitted by the Aedes genus mosquito. It causes financial burdens on public health systems and considerable morbidity and mortality. Tropical regions in the Americas and Asia are the areas most affected by the virus. Fortaleza is a city with approximately 2.6 million inhabitants in northeastern Brazil that, during the recent decades, has been suffering from endemic dengue transmission, interspersed with larger epidemics. The objective of this paper is to study the impact of human mobility in urban areas on the spread of the dengue virus, and to test whether human mobility data can be used to improve predictions of dengue virus transmission at the neighbourhood level. We present two distinct forecasting systems for dengue transmission in Fortaleza: the first using artificial neural network methods and the second developed using a mechanistic model of disease transmission. We then present enhanced versions of the two forecasting systems that incorporate bus transportation data cataloguing movement among 119 neighbourhoods in Fortaleza. Each forecasting system was used to perform retrospective forecasts for historical dengue outbreaks from 2007 to 2015. Results show that both artificial neural networks and mechanistic models can accurately forecast dengue cases, and that the inclusion of human mobility data substantially improves the performance of both forecasting systems. While the mechanistic models perform better in capturing seasons with large-scale outbreaks, the neural networks more accurately forecast outbreak peak timing, peak intensity and annual dengue time series. These results have two practical implications: they support the creation of public policies from the use of the models created here to combat the disease and help to understand the impact of urban mobility on the epidemic in large cities.

SARS-CoV-2 and Dengue Virus Coinfection in An Adult with Heterozygous Beta Thalassemia: A Case Report from Bangladesh with Literature Review

Introduction: Coinfections are common in pandemics, but not in recorded patients with structural hemoglobin abnormalities. The COVID-19 pandemic struck Bangladesh at the beginning of March 2020, which is also an apt period for endemic Dengue fever in this monsoon region. Case Report: We report a 30-year-old man with hemoglobinopathies coinfected with SARS-CoV-2 and Dengue virus. Dengue virus was detected by ELISA. COVID-19 was confirmed by RT-PCR and Hemoglobin Electrophoresis revealed heterozygous beta-thalassemia. The patient was treated successfully at Dhaka Hospital in ICDDR,B during COVID-19 emergency response with symptomatic supportive treatment for COVID-19 and appropriate fluid therapy for dengue fever in response to daily hematocrit level. After 21 day, the patient’s RT-PCR for COVID-19 became negative. For thalassemia, the patient was advised to have genetic counseling and family screening on discharge.Conclusion: The possibility of coinfection should be considered during the Dengue fever epidemic along with the confirmatory tests for COVID-19, when any alarming signs supporting possibility of dengue fever are found in an individual. Fluid therapy for dengue fever must be maintained with utmost care to avoid adverse effect from COVID-19-Dengue coinfection and careful monitoring of oxygen saturation during the sick period of this type of case should be performed with importance.

COVID-19 Virus Infection and Transmission are Observably Less in Highly Dengue-Endemic Countries: Is Pre-Exposure to Dengue Virus Protective Against COVID-19 Severity and Mortality? Will the Reverse Scenario Be True?

Global severity maps of ongoing dengue epidemic and COVID-19 pandemic do not tend to overlap. Countries with high dengue endemicity (>1.5 million cases/year) are observably less hit by COVID-19 in terms of infection, transmission and mortality. Based on non-overlap of dengue and COVID-19 severity maps in general and increasing evidences of SARS-CoV-2 false-positivity in dengue antibody tests, we wonder whether regular pre-exposure to dengue virus (DENV) in highly dengue endemic countries is providing some extent of protection against COVID-19 severity. We also wondered whether immunization of susceptible populations in dengue non-endemic countries (e.g. Europe and North America) with available live-attenuated dengue vaccines, will cue the anti-viral immune response to thwart COVID-19. Risk of developing post-vaccination antibody-dependent enhancement (ADE) is low as dengue is not endemic in the aforesaid regions. Understanding the consequences of dengue and COVID-19 co-endemicity in the upcoming days is another area of huge concern. Although, it appears that dengue-induced immunity is ‘thwarting’ COVID-19, it is not clear whether conversely, COVID-19 convalescent individuals will also be resistant to future dengue attacks. On the contrary, such individuals may show higher susceptibility to DENV due to ADE caused by cross-reactive COVID-19 antibodies. The latter may bind to DENV without neutralizing the virus; instead, such antibodies may facilitate cellular entry of DENV by means of their Fcregions attached to the susceptible cells. This possibility also cautions against complications that may arise on implementing SARS-CoV-2 vaccinations in highly dengue endemic countries.

Corrigendum to: Dengue Endemicity, Force of Infection and Variation in Transmission Intensity From 13 Endemic Countries

Corrigendum to: Dengue Endemicity, Force of Infection and Variation in Transmission Intensity From 13 Endemic Countries

Rational Vaccine Design in the Time of COVID-19

As scientists consider SARS-CoV-2 vaccine design, we discuss problems that may be encountered and how to tackle them by what we term “rational vaccine design.” We further discuss approaches to pan-coronavirus vaccines. We draw on experiences from recent research on several viruses including HIV and influenza, as well as coronaviruses.