• 1

    Rudnick A, Lim TW, 1986. Dengue fever studies in Malaysia. Inst Med Res Malaysia Bull 23 :51–152.

  • 2

    Rudnick A, 1984. The ecology of the dengue virus complex in peninsular Malaysia. T. Pang, Pathmanatan R, eds. Proceedings of the International Conference on dengue/DHF. Kuala Lampur, Malaysia: University of Malaysia Press.

  • 3

    Saluzzo JF, Cornet M, Adam C, Eyraud M, Digoutte JP, 1986. Dengue 2 in eastern Senegal: serologic survey in simian and human populations, 1974–85. Bull Soc Pathol Exot Filiales 79 :313–322.

    • Search Google Scholar
    • Export Citation
  • 4

    Rodhain F, 1991. The role of monkeys in the biology of dengue and yellow fever. Comp Immunol Microbiol Infect Dis 14 :9–19.

  • 5

    Diallo M, Ba Y, Sall AA, Diop OM, Ndione JA, Mondo M, Girault L, Mathiot C, 2003. Amplification of the sylvatic cycle of dengue virus type 2, Senegal, 1999–2000: entomologic findings and epidemiologic considerations. Emerg Infect Dis 9 :362–367.

    • Search Google Scholar
    • Export Citation
  • 6

    Saluzzo JF, Cornet M, Castagnet P, Rey C, Digoutte JP, 1986. Isolation of dengue 2 and dengue 4 viruses from patients in Senegal. Trans R Soc Trop Med Hyg 80 :5.

    • Search Google Scholar
    • Export Citation
  • 7

    Robin Y, Cornet M, Heme G, Le Gonidec G, 1980. Isolement du virus dela dengue au Senegal. Ann Virol 131 :149–154.

  • 8

    Carey DE, Causey OR, Reddy S, Cooke AR, 1971. Dengue viruses from febrile patients in Nigeria, 1964–68. Lancet 1 :105–106.

  • 9

    Vasilakis N, Tesh RB, Weaver SC, 2008. Sylvatic dengue virus type 2 activity in humans, Nigeria, 1966. Emerg Infect Dis 14 :502–504.

  • 10

    Wang E, Ni H, Xu R, Barrett AD, Watowich SJ, Gubler DJ, Weaver SC, 2000. Evolutionary relationships of endemic/ epidemic and sylvatic dengue viruses. J Virol 74 :3227–3234.

    • Search Google Scholar
    • Export Citation
  • 11

    Moncayo AC, Fernandez Z, Ortiz D, Diallo M, Sall A, Hartman S, Davis CT, Coffey L, Mathiot CC, Tesh RB, Weaver SC, 2004. Dengue emergence and adaptation to peridomestic mosquitoes. Emerg Infect Dis 10 :1790–1796.

    • Search Google Scholar
    • Export Citation
  • 12

    Diallo M, Sall AA, Moncayo AC, Ba Y, Fernandez Z, Ortiz D, Coffey LL, Mathiot C, Tesh RB, Weaver SC, 2005. Potential role of sylvatic and domestic African mosquito species in dengue emergence. Am J Trop Med Hyg 73 :445–449.

    • Search Google Scholar
    • Export Citation
  • 13

    Vasilakis N, Shell EJ, Fokam EB, Mason PW, Hanley KA, Estes DM, Weaver SC, 2007. Potential of ancestral sylvatic dengue-2 viruses to re-emerge. Virology 358 :402–412.

    • Search Google Scholar
    • Export Citation
  • 14

    Vasilakis N, Holmes EC, Fokam EB, Faye O, Diallo M, Sall AA, Weaver SC, 2007. Evolutionary processes among sylvatic dengue-2 viruses. J Virol 81 :9591–9595.

    • Search Google Scholar
    • Export Citation
  • 15

    Blaney JE Jr, Durbin AP, Murphy BR, Whitehead SS, 2006. Development of a live attenuated dengue virus vaccine using reverse genetics. Viral Immunol 19 :10–32.

    • Search Google Scholar
    • Export Citation
  • 16

    Durbin AP, McArthur JH, Marron JA, Blaney JE, Thumar B, Wanionek K, Murphy BR, Whitehead SS, 2006. rDEN2/ 4Delta30(ME), a live attenuated chimeric dengue serotype 2 vaccine is safe and highly immunogenic in healthy dengue-naive adults. Hum Vaccin 2 :255–260.

    • Search Google Scholar
    • Export Citation
  • 17

    Deauvieau F, Sanchez V, Balas C, Kennel A, de Montfort A, Lang J, Guy B, 2007. Innate immune responses in human dendritic cells upon infection by chimeric yellow-fever dengue vaccine serotypes 1–4. Am J Trop Med Hyg 76 :144–154.

    • Search Google Scholar
    • Export Citation
  • 18

    Guirakhoo F, Pugachev K, Zhang Z, Myers G, Levenbook I, Draper K, Lang J, Ocran S, Mitchell F, Parsons M, Brown N, Brandler S, Fournier C, Barrere B, Rizvi F, Travassos A, Nichols R, Trent D, Monath T, 2004. Safety and efficacy of chimeric yellow fever-dengue virus tetravalent vaccine formulations in nonhuman primates. J Virol 78 :4761–4775.

    • Search Google Scholar
    • Export Citation
  • 19

    Durbin AP, McArthur J, Marron JA, Blaney JE Jr, Thumar B, Wanionek K, Murphy BR, Whitehead SS, 2006. The live attenuated dengue serotype 1 vaccine rDEN1Delta30 is safe and highly immunogenic in healthy adult volunteers. Hum Vaccin 2 :167–173.

    • Search Google Scholar
    • Export Citation
  • 20

    Durbin AP, Whitehead SS, McArthur J, Perreault JR, Blaney JE Jr, Thumar B, Murphy BR, Karron RA, 2005. rDEN4delta30, a live attenuated dengue virus type 4 vaccine candidate, is safe, immunogenic, and highly infectious in healthy adult volunteers. J Infect Dis 191 :710–718.

    • Search Google Scholar
    • Export Citation
  • 21

    Durbin AP, Karron RA, Sun W, Vaughn DW, Reynolds MJ, Perreault JR, Thumar B, Men R, Lai CJ, Elkins WR, Chanock RM, Murphy BR, Whitehead SS, 2001. Attenuation and immunogenicity in humans of a live dengue virus type-4 vaccine candidate with a 30 nucleotide deletion in its 3′-untranslated region. Am J Trop Med Hyg 65 :405–413.

    • Search Google Scholar
    • Export Citation
  • 22

    Blaney JE Jr, Matro JM, Murphy BR, Whitehead SS, 2005. Recombinant, live-attenuated tetravalent dengue virus vaccine formulations induce a balanced, broad, and protective neutralizing antibody response against each of the four serotypes in rhesus monkeys. J Virol 79 :5516–5528.

    • Search Google Scholar
    • Export Citation
  • 23

    Whitehead SS, Hanley KA, Blaney JE Jr, Gilmore LE, Elkins WR, Murphy BR, 2003. Substitution of the structural genes of dengue virus type 4 with those of type 2 results in chimeric vaccine candidates which are attenuated for mosquitoes, mice, and rhesus monkeys. Vaccine 21 :4307–4316.

    • Search Google Scholar
    • Export Citation
  • 24

    Kuno G, Gubler DJ, Oliver A, 1993. Use of original’antigenic sin’ theory to determine the serotypes of previous dengue infections. Trans R Soc Trop Med Hyg 87 :103–105.

    • Search Google Scholar
    • Export Citation
  • 25

    Halstead SB, Rojanasuphot S, Sangkawibha N, 1983. Original antigenic sin in dengue. Am J Trop Med Hyg 32 :154–156.

  • 26

    Chien LJ, Liao TL, Shu PY, Huang JH, Gubler DJ, Chang GJ, 2006. Development of real-time reverse transcriptase PCR assays to detect and serotype dengue viruses. J Clin Microbiol 44 :1295–1304.

    • Search Google Scholar
    • Export Citation
  • 27

    Sabin AB, 1952. Research on dengue during World War II. Am J Trop Med Hyg 1 :30–50.

 

 

 

 

 

Antigenic Relationships between Sylvatic and Endemic Dengue Viruses

View More View Less
  • 1 Center for Biodefense and Emerging Infectious Diseases, and Department of Pathology, University of Texas Medical Branch, Galveston, Texas; Center for Immunization Research, Department of International Health, Johns Hopkins Bloomberg School of Public Health, Baltimore, Maryland; Molecular Virology and Surveillance Laboratory, Centers for Disease Control and Prevention Dengue Branch, San Juan, Puerto Rico

Sylvatic dengue viruses (DENVs) are transmitted between non-human primates and arboreal Aedes spp. mosquitoes in Southeast Asia and west Africa. Recent evidence suggests that the risk for re-emergence of sylvatic DENV into the urban endemic/epidemic cycle may be high, which could limit the potential for eradicating the human transmission cycle with vaccines now under development. We assessed the likelihood of sylvatic DENV re-emergence in the face of immunity to current endemic strains or vaccines by evaluating the neutralization capacity of sera from DENV vaccinees and convalescent patients after primary infection with DENV-2 and DENV-3 serotypes. Our data indicate robust homotypic cross-immunity between human sera and sylvatic DENV strains, but limited heterotypic neutralization. Should a licensed vaccine lead to the eradication of the urban transmission cycle in the future, re-emergence of sylvatic strains into the urban cycle would be limited by homotypic immunity mediated by virus-neutralizing antibodies.

Sylvatic dengue viruses (DENVs) are both ecologically and evolutionary distinct from urban DENVs and are transmitted in an enzootic cycle most likely between non-human primates and arboreal Aedes spp. mosquitoes. In Southeast Asia, isolations of zoonotic DENV-1, DENV-2, and DENV-4 suggest an association between Macaca and Presbytis spp. monkeys with Aedes niveus mosquitoes as the primary vectors.1 Sylvatic DENV-3 has not been isolated but is presumed to exist in Malaysian sylvatic cycle on the basis of seroconversions in sentinel monkeys.2 Sylvatic DENV cycles have also been documented in west Africa, where DENV-2 circulates among Erythrocebus patas and possibly other monkeys, and sylvatic Aedes mosquitoes, including Ae. taylori, Ae. furcifer, and Ae. luteocephalus, in a sylvatic focus near Kedougou, Senegal.35 Limited spillover transmission of sylvatic DENV to humans has been documented in west Africa,6,7 but until recently, the available data suggested that these sylvatic viruses were confined to forest habitats. However, recent phylogenetic and seroepidemiologic evidence suggests that spillover epidemics do occasionally occur into urban settings.8,9

Phylogenetic analyses suggest that the recent emergence of endemic, human DENV from sylvatic progenitors in Asia occurred within the past 1,000 years.10 However, hyperendemic, urban DENV probably arose in Southeast Asia and eventually globally after the invasion of the highly efficient, anthropophilic vector Ae. aegypti aegypti. This process may also have been facilitated by adaptation of DENV from the arboreal canopydwelling, ancestral Aedes spp. vectors (other than Ae. albopictus and Ae. aegypti) to the peridomestic, an-thropophilic mosquitoes Ae. aegypti and Ae. albopictus.11 However, recent analyses using a larger number and diversity of isolates have not supported this hypothesis (Vasilakis N, unpublished data, and Hanley K, unpublished data). Recent reports have also shown that the forest canopydwelling mosquito Ae. furcifer is highly susceptible to sylvatic DENV infection.12 Aedes furcifer shows a pattern of movement into villages in eastern Senegal,5 which suggests that this species may act as a bridge vector for exchange of DENV between forest and peridomestic habitats. Furthermore, the ability of Ae. aegypti and Ae. albopictus to transmit sylvatic DENV-212 indicates that little or no change in vector infectivity accompanied endemic emergence from sylvatic progenitors. Finally, the ability of sylvatic DENV-2 to replicate efficiently in two model systems for human infection, monocyte-derived, human dendritic cells (maDCs), and mice engrafted with human hepatoma cells,13 as well as recent evidence of rapid sylvatic DENV turnover caused by their high nucleotide substitution rates across the genome,14 suggest the risk for sylvatic DENV-2 re-emergence into an urban cycle may be high. This finding could limit the potential for eradicating the human transmission cycle with the dengue vaccines now under development.1518

We assessed the likelihood of current sylvatic DENV re-emergence in the face of immunity to current urban strains or vaccine candidates by evaluating the neutralizing capacity of sera from DENV vaccinees and convalescent patients against geographically and genetically diverse sylvatic and urban DENV strains (Table 1). This information may allow us to predict the long-term success of candidate vaccines currently under development, and evaluate the degree to which pre-existing antibodies to urban DENV-2 in the human population could prevent the re-emergence of sylvatic DENV-2. In other words, if endemic DENV cycles were eradicated by vaccination, would cross-immunity against sylvatic strains prevent their re-emergence as long as herd immunity remained above a threshold level needed to prevent efficient urban transmission?

First, we used a modified plaque reduction neutralization test (PRNT) to evaluate the neutralizing capacity of sera from 26 (18 test and 8 placebo), 27 (19 test and 8 placebo), and 24 (20 test and 4 placebo) DENV vaccinees16,19,20 collected 42 days post-vaccination with the rDEN1Δ30, rDEN2/4Δ30, and rDEN4Δ30 vaccine candidates, respectively. The vaccine candidate rDEN4Δ30, a live recombinant DENV-4 virus, was derived from the 814669 (Dominica/81) strains and contains a 30-nucleotide deletion in the 3′ non-coding genome region.21 Strain rDEN1Δ30 was derived from the Nauru/74 strain and contains a 30-nucleotide deletion in the 3′ non-coding genome region.19,22 Strain rDEN2/4Δ30 was derived from the rDEN4Δ30 virus and the prototypic DEN2 strain New Guinea C. The premembrane and envelope proteins of DENV-4 were replaced with those of NGC.23

The PRNT was performed in 12-well, Vero-microplate-cell cultures using a fixed virus inoculum (approximately 800 focus-forming units) against varying serum dilutions (1:20–1:2,560). Serum samples were diluted in minimal essential medium (MEM) containing 2% fetal bovine serum. Virus was mixed with an equal volume of each serum dilution (1:20–1:2,560) and the mixture was incubated for one hour at 37°C. A 250-μL volume of the serum–virus mixture was then placed into Vero cultures and incubated for one hour at 37°C. A 1-mL volume of 4% methycellulose in OPTIMEM-I overlay (GIBCO BRL, Gaithersburg, MD) was placed in each well and the plates were incubated for four days at 37°C. The plates were then fixed with 1:1 methanol:acetone and foci were stained immunologically and counted to determine the level of virus neutralization as described previously.13 The PRNT titers were scored as the reciprocal of the highest dilution of serum that inhibited 80% of the foci (PRNT80; data not shown). Although some DENV studies use lower reduction percentages to report titers, we used the 80% endpoint to estimate conservatively in vivo protection.

Sera from all eight placebo-vaccinated persons were unable to neutralize any DENV tested (PRNT80 < 20). Our data indicated that rDEN2/4Δ30 vaccination or DENV-2 infection elicited a robust, homotypic virus neutralization responses against both urban and sylvatic DENV-2 strains (PRNT80 = 20–1,280 and 20–640, respectively). Only one sample from a DENV-2–vaccinated person exhibited any heterotypic virus-neutralizing activity (Table 2).

All but four sera from persons vaccinated with rDEN1Δ30 exhibited a homotypic virus neutralization response (PRNT80 = 40–640) against the endemic DENV-1 strain. Although only one of these volunteers failed to seroconvert in a previous study,19 this discrepancy is caused by the stringency of our assay (PRNT80 versus PRNT60 used previously). Sera from 7 of these 18 rDEN1Δ30–vaccinated persons failed to neutralize the sylvatic DENV-1 strain P72-1244 at the sensitivity range of our test system (PRNT80 < 20; Table 3). Sera from seven of these vaccinated persons exhibited weak heterotypic virus neutralization to DENV-2 and DENV-4 (PRNT80 = 20–40) (Table 3).

In a similar manner to sera from DENV-1 vaccinees, sera from rDEN4Δ30 vaccinees exhibited relatively weak homotypic neutralization (PRNT80 = 20–40) (Table 4). Sera from three of these vaccinated persons exhibited heterotypic virus neutralization to DENV-2 (range of reciprocal PRNT80 = 40–160), whereas serum from one vaccinated person exhibited a relatively strong virus neutralizing response DENV-2 (PRNT80 = 320–> 1,280) (Table 4). For the latter person, we obtained a similar profile by hemagglutination inhibition assay; data not shown. Although volunteer participation in this vaccine trial included stringent eligibility criteria, including absence to prior exposure to flaviviruses,19 the volunteer’s robust neutralization titer (> 1,280) to DENV-2 suggests a possible secondary antibody response (previous DENV-2 infection) and “original antigenic sin.”24,25 This concept was proposed by Halstead and others25 as a mechanism of DENV immune response involved in sequential infections, where response to a secondary infection is dominated by the proliferation of cross-reacting memory cells induced by the primary infection, which may be of lower affinity for the secondary challenging antigen. However, it is very unlikely that volunteer no. 12 would have been exposed to any flavivirus because this person was a Baltimore resident with no travel history to DENV-endemic countries. This volunteer was thoroughly screened and found to be negative for previous flavivirus infection. The person had day 0 (prior to vaccination) DENV PRNT60 titers < 10 for all four DENV, yellow fever virus, and West Nile virus. In addition, hemagglutination inhibition titers to St. Louis encephalitis virus, West Nile virus, and Japanese encephalitis virus were also negative prior to vaccination. The postvaccination titer was not unusual for DENV infection.

We next examined the ability of sera from convalescent patients after primary infection with DENV-2 or DENV-3 to neutralize sylvatic DENV-2. Primary cases were defined by positive virus identification by reverse transcription–polymerase chain reaction (DENV-2 or DENV-3)26 and IgG antibody titer ≤ 1:80 during the acute phase of disease (0–5 days after onset of symptoms). Paired, convalescent serum specimens obtained 12–20 days after the onset of symptoms were used for neutralization assays. These specimens were obtained from routine surveillance, and were de-identified and approved for research studies under institutional review board exemption 4797 at the Centers for Disease Control and Prevention. Because no sylvatic DENV-3 have been isolated,2 we only tested for the neutralization capacity of DENV-3 sera against endemic DENV-3. Furthermore, the limited volume of available sera prohibited us from evaluating their neutralization capacity with a large collection of DENV strains or genotypes.

Sera from convalescent patients with primary DENV-2 infection exhibited robust homotypic neutralization capacity for both urban and sylvatic DENV-2 (PRNT80 = 80–> 1,280) and no heterotypic virus neutralization of DENV-3 (Table 5). Similarly, sera from primary DENV-3 infection exhibited robust homotypic neutralization for DENV-3 (PRNT80 = 80–320) and no heterotypic neutralization for either urban or sylvatic DENV-2 (Table 5). Control sera from two consenting healthy volunteers with no history of DENV infection were unable to neutralize any DENV (PRNT80< 20; data not shown).

Collectively, our findings demonstrate the capacity of sera from DENV-vaccinated persons and convalescent patients after primary infection with DENV-2 and DENV-3 serotypes to neutralize geographically and genetically diverse sylvatic and urban DENV-2 strains because of strong homotypic immunity. Furthermore, our data suggest limited heterotypic virus neutralization activity in sera of DENV-vaccinated persons, consistent with Sabin’s observation that DENV infection produces protection for up to 12 weeks against disease caused by heterotypic infection.27 Thus, should a licensed vaccine lead to the eradication of the urban dengue transmission cycle in the future, re-emergence of sylvatic strains into an urban cycle may be limited by homotypic humoral immunity. However, the danger of endemic DENV re-emergence will remain as long as vaccine coverage is incomplete and Ae. aegypti and/or Ae. albopictus remain in sufficient numbers.

Several lines of evidence suggest that re-emergence of current sylvatic DENV into the urban human transmission cycle is quite likely,1214 and could pose a major public health problem. If DENV can readily re-emerge from sylvatic cycles not amenable to intervention, the reduction and ultimate eradication of dengue from human populations solely by vaccination campaigns could be, at best, short-lived. Successful eradication of dengue will hinge on sustained vaccination of the susceptible populations at risk to introduction of sylvatic DENV, as well as control of the urban mosquito vectors.

Table 1

Sylvatic and endemic dengue virus (DENV) strains used in this study*

Isolate†SerotypeHost‡Epidemiologic type§ (genotype)LocationYearGenBank accession no.
*NA = not available.
†DENV isolates were obtained from the University of Texas Medical Branch World Reference Center for Emerging Viruses and Arboviruses.
‡Source of virus isolation.
§Endemic indicates human or Ae. aegypti isolates or those associated with peridomestic transmission; sylvatic indicates sentinel monkey or canopy-dwelling mosquito isolate.
P75-12441Aedes niveusSylvaticMalaysia1975EF457905
OBS76901HumanEndemicBolivia1999NA
166812HumanEndemic (Asian)Thailand1964U87411
13492HumanEndemic (Cosmopolitan)Burkina Faso1982M32939
IQT-19502HumanEndemic (American)Peru1995DQ91724
13282HumanEndemic (American)Puerto Rico1977DQ917243
P8-14072Sentinel monkeySylvaticMalaysia1970EF105379
Dak Ar 5102Ae. tayloriSylvaticIvory Coast1980EF105381
Dak Ar A12472Ae. tayloriSylvaticIvory Coast1980EF105383
Dak Ar A20222Ae. africanusSylvaticBurkina Faso1980EF105386
FSP-0323HumanEndemicPeru2000?NA
P75-2154Ae. niveusSylvaticMalaysia1975EF457906
H2414HumanEndemicThe Philippines1956AY947539
Table 2

Homotypic and heterotypic neutralization by dengue virus 2 (DENV-2) sera from persons inoculated with candidate DENV-2 vaccine*

Virus
Endemic DENV-2
AsianAmericanSylvatic DENV-2DENV-4DENV-1
DENV-2-immune sera†166811349IQT19501328P8-1407Dak Ar A510Dak Ar A1247Dak Ar A2022Endemic H241Sylvatic P75-125Endemic OBS7690Sylvatic P72-1244
* Neutralization was defined as an 80% reduction in the plaque reduction neutralization test.
†Sera were obtained from healthy human vaccinees 42 days post-vaccination with rDEN2/4Δ30.
1808016080320640320160< 20< 20< 20< 20
2804032080160320160160< 20< 20< 20< 20
340160808016016016040< 20< 20< 20< 20
4408032080401604040< 20< 20< 20< 20
516040808016016032080< 20< 20< 20< 20
6160803208020804040< 20< 20< 20< 20
72040804080808040< 20< 2040< 20
82016040808016016040< 20< 20< 20< 20
9160> 1,280808016016016040< 20< 20< 20< 20
101608016016016080160160< 20< 20< 20< 20
1180160320160320160160160< 20< 20< 20< 20
12808080160160160160160< 20< 20< 20< 20
1316080404040808080< 20< 20< 20< 20
148080808080160160160< 20< 20< 20< 20
1532080160320160160160320< 204080< 20
168080808080804080< 20< 2040< 20
172040804080804040< 20< 20< 20< 20
188080160808080160160< 20< 20< 20< 20
19808080160640320160160< 20< 20< 20< 20
Table 3

Homotypic and heterotypic neutralization by dengue virus 1 (DENV-1) sera from persons inoculated with candidate DENV-1 vaccine*

Virus
Endemic DENV-2
AsianAmericanSylvatic DENV-2DENV-4DENV-1
DENV-2-immune sera†166811349IQT19501328P8-1407Dak Ar A510Dak Ar A1247Dak Ar A2022Endemic H241Sylvatic P75-125Endemic OBS7690Sylvatic P72-1244
* Neutralization was defined as an 80% reduction in the plaque reduction neutralization test. NT = not tested.
† Sera obtained from healthy human vaccinees 42 days post-vaccination with rDEN1Δ30.
1< 20< 20< 2020< 20< 20< 2040< 20< 2064040
2< 20< 20< 2020< 20< 20< 20< 20< 20< 2016020
3< 20< 20< 20< 20< 20< 20< 20< 20< 20< 20< 20< 20
4< 20< 20< 20< 20< 20< 20< 20< 20< 20< 204020
5< 20< 20< 20< 20< 20< 20< 20< 20< 20< 20NT< 20
6< 20< 20< 20< 20< 20< 20< 20< 20< 20< 208040
7< 20< 20< 20< 20< 20< 20< 20< 20< 20< 20< 20< 20
8< 20< 20< 20< 20< 2040< 20< 20< 20< 2040< 20
9< 20< 20< 20< 20< 2040< 20< 20< 20< 2016040
10< 20< 20< 2020< 2040< 20< 20< 20< 2016040
11< 20< 20< 20< 20< 20< 20< 20< 20< 20< 20< 20< 20
12< 20< 20< 20< 20< 20< 20< 20< 20< 2040< 20< 20
13< 20< 20< 20< 20< 20< 20< 20< 20< 20< 204020
1440< 20< 20< 20< 2040< 20< 20< 20< 208020
15< 20< 20< 20< 20< 20< 20< 20< 20< 20< 204020
16< 20< 20< 20< 20< 20< 20< 20< 20< 20< 2080< 20
17< 20< 20< 20< 20< 20< 20< 20< 20< 20< 2016040
18< 20< 20< 20< 20< 20< 20< 20< 20< 20< 208020
Table 4

Homotypic and heterotypic neutralization by dengue virus 4 (DENV-4) vaccinee sera from persons inoculated with candidate DENV-4 vaccine*

Virus
Endemic DENV-2
AsianAmericanSylvatic DENV-2DENV-4DENV-1
DENV-2-immune sera†166811349IQT19501328P8-1407Dak Ar A510Dak Ar A1247Dak Ar A2022Endemic H241Sylvatic P75-125Endemic OBS7690Sylvatic P72-1244
* Neutralization was defined as an 80% reduction measured by plaque reduction neutralization test.
† Sera were obtained from healthy human vaccinees 42 days post-vaccination with rDEN4Δ30.
1< 20< 20< 20< 20< 20< 20< 20404020< 20< 20
2< 20< 20< 20< 20< 20< 20< 20< 208020< 20< 20
3< 20< 20< 20< 20< 20< 20< 20< 2016020< 20< 20
4< 20< 20< 20< 20< 20< 20< 20< 204020< 20< 20
5< 20< 20< 20< 20< 20< 20< 20< 202020< 20< 20
6< 20< 20< 20< 20< 20< 20< 20< 2016040< 20< 20
7< 20< 20< 20< 20< 20< 20< 20< 208040< 20< 20
8< 20< 20< 20< 20< 20< 20< 20< 2016040< 20< 20
9< 20< 20< 20< 20< 20< 20< 20< 20402040< 20
10< 20< 20< 20< 20< 20< 20< 20< 2016020< 20< 20
11< 20< 20< 20< 20< 2040< 20< 208020< 20< 20
12320> 640> 1,280> 640> 640> 1,280> 1,280> 1,2804040< 20< 20
13< 20< 20< 20< 20< 20< 20< 20< 204020< 20< 20
14160< 20< 2020< 208040404020< 20< 20
15< 20< 20< 20< 20< 20< 20< 20< 204020< 20< 20
16< 20< 20< 20< 20< 20< 20< 20< 204020< 20< 20
17< 20< 20< 20< 20< 20< 20< 20< 204020< 20< 20
18< 20< 20< 20< 20< 20< 20< 20< 208020< 20< 20
19< 20< 20< 20< 20< 20< 20< 20< 204020< 20< 20
20< 20< 20< 20< 20< 20< 20< 20< 204020< 20< 20
Table 5

Homotypic and heterotypic dengue virus 2 (DENV-2) and DENV-3 neutralization by convalescent patient sera*

Virus
Asian DENV-2American DENV-2Sylvatic DENV-2
DENV-2166811349IQT-19501328P8-1407Dak Ar A510Dak Ar A2022Dak Ar A1247DENV-3FSP-032
* Neutralization was defined as an 80% reduction measured by plaque reduction neutralization test.
    1> 1,2801603201608032032080< 20
    21,280320320320160320640320< 20
DENV-3
    1< 20< 20< 20< 20< 20< 20< 20< 20320
    2< 20< 20< 20< 20< 20< 20< 20< 2080

*

Address correspondence to Scott C. Weaver, Center for Biodefense and Emerging Infectious Diseases, and Department of Pathology Keiller 3.135, 301 University Boulevard, University of Texas Medical Branch, Galveston, TX 77555-0609. E-mail: sweaver@utmb.edu

Authors’ addresses: Nikos Vasilakis, Center for Vaccine Research, University of Pittsburgh, 9051 Biomedical Sciences Tower 3, 3501 Fifth Avenue, Pittsburgh, PA 15261. Anna P. Durbin, Center for Immunization Research, Department of International Health, Johns Hopkins Bloomberg School of Public Health, Hampton House, 624 North Broadway, Baltimore, MD 21205. Amelia P. A. Travassos da Rosa, Robert B. Tesh, and Scott C. Weaver, Center for Biodefense and Emerging Infectious Diseases, and Department of Pathology, University of Texas Medical Branch, 301 University Boulevard, Keiller Building, Galveston, TX 77555-0609. Jorge L. Munoz-Jordan, Molecular Virology and Surveillance Laboratory, Center for Disease Control and Prevention, Dengue Branch, San Juan, PR 00920.

Acknowledgments: We thank M. Estes for critical review of the manuscript.

Financial support: Nikos Vasilakis was supported by the Centers for Disease Control and Prevention Fellowship Training Program in Vector-Borne Infectious Diseases (T01/CCT622892).

Disclosure: The authors have no conflicting financial interests.

REFERENCES

  • 1

    Rudnick A, Lim TW, 1986. Dengue fever studies in Malaysia. Inst Med Res Malaysia Bull 23 :51–152.

  • 2

    Rudnick A, 1984. The ecology of the dengue virus complex in peninsular Malaysia. T. Pang, Pathmanatan R, eds. Proceedings of the International Conference on dengue/DHF. Kuala Lampur, Malaysia: University of Malaysia Press.

  • 3

    Saluzzo JF, Cornet M, Adam C, Eyraud M, Digoutte JP, 1986. Dengue 2 in eastern Senegal: serologic survey in simian and human populations, 1974–85. Bull Soc Pathol Exot Filiales 79 :313–322.

    • Search Google Scholar
    • Export Citation
  • 4

    Rodhain F, 1991. The role of monkeys in the biology of dengue and yellow fever. Comp Immunol Microbiol Infect Dis 14 :9–19.

  • 5

    Diallo M, Ba Y, Sall AA, Diop OM, Ndione JA, Mondo M, Girault L, Mathiot C, 2003. Amplification of the sylvatic cycle of dengue virus type 2, Senegal, 1999–2000: entomologic findings and epidemiologic considerations. Emerg Infect Dis 9 :362–367.

    • Search Google Scholar
    • Export Citation
  • 6

    Saluzzo JF, Cornet M, Castagnet P, Rey C, Digoutte JP, 1986. Isolation of dengue 2 and dengue 4 viruses from patients in Senegal. Trans R Soc Trop Med Hyg 80 :5.

    • Search Google Scholar
    • Export Citation
  • 7

    Robin Y, Cornet M, Heme G, Le Gonidec G, 1980. Isolement du virus dela dengue au Senegal. Ann Virol 131 :149–154.

  • 8

    Carey DE, Causey OR, Reddy S, Cooke AR, 1971. Dengue viruses from febrile patients in Nigeria, 1964–68. Lancet 1 :105–106.

  • 9

    Vasilakis N, Tesh RB, Weaver SC, 2008. Sylvatic dengue virus type 2 activity in humans, Nigeria, 1966. Emerg Infect Dis 14 :502–504.

  • 10

    Wang E, Ni H, Xu R, Barrett AD, Watowich SJ, Gubler DJ, Weaver SC, 2000. Evolutionary relationships of endemic/ epidemic and sylvatic dengue viruses. J Virol 74 :3227–3234.

    • Search Google Scholar
    • Export Citation
  • 11

    Moncayo AC, Fernandez Z, Ortiz D, Diallo M, Sall A, Hartman S, Davis CT, Coffey L, Mathiot CC, Tesh RB, Weaver SC, 2004. Dengue emergence and adaptation to peridomestic mosquitoes. Emerg Infect Dis 10 :1790–1796.

    • Search Google Scholar
    • Export Citation
  • 12

    Diallo M, Sall AA, Moncayo AC, Ba Y, Fernandez Z, Ortiz D, Coffey LL, Mathiot C, Tesh RB, Weaver SC, 2005. Potential role of sylvatic and domestic African mosquito species in dengue emergence. Am J Trop Med Hyg 73 :445–449.

    • Search Google Scholar
    • Export Citation
  • 13

    Vasilakis N, Shell EJ, Fokam EB, Mason PW, Hanley KA, Estes DM, Weaver SC, 2007. Potential of ancestral sylvatic dengue-2 viruses to re-emerge. Virology 358 :402–412.

    • Search Google Scholar
    • Export Citation
  • 14

    Vasilakis N, Holmes EC, Fokam EB, Faye O, Diallo M, Sall AA, Weaver SC, 2007. Evolutionary processes among sylvatic dengue-2 viruses. J Virol 81 :9591–9595.

    • Search Google Scholar
    • Export Citation
  • 15

    Blaney JE Jr, Durbin AP, Murphy BR, Whitehead SS, 2006. Development of a live attenuated dengue virus vaccine using reverse genetics. Viral Immunol 19 :10–32.

    • Search Google Scholar
    • Export Citation
  • 16

    Durbin AP, McArthur JH, Marron JA, Blaney JE, Thumar B, Wanionek K, Murphy BR, Whitehead SS, 2006. rDEN2/ 4Delta30(ME), a live attenuated chimeric dengue serotype 2 vaccine is safe and highly immunogenic in healthy dengue-naive adults. Hum Vaccin 2 :255–260.

    • Search Google Scholar
    • Export Citation
  • 17

    Deauvieau F, Sanchez V, Balas C, Kennel A, de Montfort A, Lang J, Guy B, 2007. Innate immune responses in human dendritic cells upon infection by chimeric yellow-fever dengue vaccine serotypes 1–4. Am J Trop Med Hyg 76 :144–154.

    • Search Google Scholar
    • Export Citation
  • 18

    Guirakhoo F, Pugachev K, Zhang Z, Myers G, Levenbook I, Draper K, Lang J, Ocran S, Mitchell F, Parsons M, Brown N, Brandler S, Fournier C, Barrere B, Rizvi F, Travassos A, Nichols R, Trent D, Monath T, 2004. Safety and efficacy of chimeric yellow fever-dengue virus tetravalent vaccine formulations in nonhuman primates. J Virol 78 :4761–4775.

    • Search Google Scholar
    • Export Citation
  • 19

    Durbin AP, McArthur J, Marron JA, Blaney JE Jr, Thumar B, Wanionek K, Murphy BR, Whitehead SS, 2006. The live attenuated dengue serotype 1 vaccine rDEN1Delta30 is safe and highly immunogenic in healthy adult volunteers. Hum Vaccin 2 :167–173.

    • Search Google Scholar
    • Export Citation
  • 20

    Durbin AP, Whitehead SS, McArthur J, Perreault JR, Blaney JE Jr, Thumar B, Murphy BR, Karron RA, 2005. rDEN4delta30, a live attenuated dengue virus type 4 vaccine candidate, is safe, immunogenic, and highly infectious in healthy adult volunteers. J Infect Dis 191 :710–718.

    • Search Google Scholar
    • Export Citation
  • 21

    Durbin AP, Karron RA, Sun W, Vaughn DW, Reynolds MJ, Perreault JR, Thumar B, Men R, Lai CJ, Elkins WR, Chanock RM, Murphy BR, Whitehead SS, 2001. Attenuation and immunogenicity in humans of a live dengue virus type-4 vaccine candidate with a 30 nucleotide deletion in its 3′-untranslated region. Am J Trop Med Hyg 65 :405–413.

    • Search Google Scholar
    • Export Citation
  • 22

    Blaney JE Jr, Matro JM, Murphy BR, Whitehead SS, 2005. Recombinant, live-attenuated tetravalent dengue virus vaccine formulations induce a balanced, broad, and protective neutralizing antibody response against each of the four serotypes in rhesus monkeys. J Virol 79 :5516–5528.

    • Search Google Scholar
    • Export Citation
  • 23

    Whitehead SS, Hanley KA, Blaney JE Jr, Gilmore LE, Elkins WR, Murphy BR, 2003. Substitution of the structural genes of dengue virus type 4 with those of type 2 results in chimeric vaccine candidates which are attenuated for mosquitoes, mice, and rhesus monkeys. Vaccine 21 :4307–4316.

    • Search Google Scholar
    • Export Citation
  • 24

    Kuno G, Gubler DJ, Oliver A, 1993. Use of original’antigenic sin’ theory to determine the serotypes of previous dengue infections. Trans R Soc Trop Med Hyg 87 :103–105.

    • Search Google Scholar
    • Export Citation
  • 25

    Halstead SB, Rojanasuphot S, Sangkawibha N, 1983. Original antigenic sin in dengue. Am J Trop Med Hyg 32 :154–156.

  • 26

    Chien LJ, Liao TL, Shu PY, Huang JH, Gubler DJ, Chang GJ, 2006. Development of real-time reverse transcriptase PCR assays to detect and serotype dengue viruses. J Clin Microbiol 44 :1295–1304.

    • Search Google Scholar
    • Export Citation
  • 27

    Sabin AB, 1952. Research on dengue during World War II. Am J Trop Med Hyg 1 :30–50.

Save