Table 4.
Serological and molecular assays utilized in rickettsial investigations by country.
| Countries | Source of assays* | Serologic evidence of rickettsial infections (group-specific assays) Molecular evidence of rickettsiae (genus-, group-, and/or species-specific assays) | ||
|---|---|---|---|---|
| Type of assays** | Specific assays*** | Host samples**** | ||
| Azerbaijan | NMRC | ELISAs | TGR- and SFGR-ELISAs-IgG | Human sera |
| qPCR | Rick17, Trick, RfelG, Raesch, Rraoul, Rslov | Tick | ||
| Chile | NMRC | ELISAs | STGO | Human serum |
| OSU | Sequencing | rrs | Human eschar | |
| NMRC | ELISA | STGO | Dog sera | |
| InBios Fuller Laboratories | ELISA-IgMIFA-IgG | O. tsutsugamushi antigens | Human serum | |
| NMRC | qPCR | Otsu47 | Human eschar | |
| MLST | rrs, htrA, and tsa56 | Human eschar | ||
| InBios Fuller Laboratories | ELISA-IgM and IgGIFA-IgG | O. tsutsugamushi antigens | Human sera | |
| NMRC | qPCR | Orien16S | Human eschas | |
| MLST | rrs and htrA | |||
| NMRC | qPCR | Orien16S | Mites | |
| NMRC | qPCR | Orien16S | Human eschars and buffy coat | |
| PUCC | MLST | rrs, htrA, and tsa56 | ||
| NMRC | ELISAs | TGR-, SFGR-, and STGO-ELISAs-IgG | Human sera | |
| Georgia | NMRC | qPCR assays | Rick17, Trick, Raesch, Rraoul, Rslov | Ticks |
| MLST | gltA, ompA, ompB, sca4 | |||
| ELISAs | TGR- and SFGR-ELISAs-IgG | Human sera | ||
| qPCR assays | Rick17b, Rraoul, Rslov, Raesch, Rmona, Rconor, Rmass9666 | Ticks | ||
| MLST | gltA, ompA, ompB, sca4 | |||
| India | NMRC | ELISAs | TGR-, SFGR-, and STGO-ELISAs-IgG | Human sera |
| InBios | ELISA | InBios Scrub typhus ELISA-IgM | ||
| NMRC | Sequencing | tsa56 | Human blood | |
| ELISAs | TGR-, SFGR-, and STGO-ELISAs-IgG | Human sera | ||
| MLST | 17kDa, gltA, ompA, ompB, sca4 | Human blood | ||
| ELISA | TGR-ELISA-IgG | Human sera | ||
| Kazakhstan | USAMRIID | qPCR assays | Dermacentor, Hyalommma, Rhipicephalus, and Ixodes genus-specific assays | Ticks |
| NMRC | qPCR | Rick17b | Ticks | |
| qPCR | Rick17b | Ticks | ||
| qPCR assays | Rick17b, Raesch, Rraoul, Rslov | Ticks | ||
| qPCR assays | Rick17b, Rtyph, RfelG, RfelB, Rasemb | Rodent fleas | ||
| Madagascar | NMRC | ELISAs | TGR- and SFGR-ELISAs-IgG | Human seraSmall mammal sera |
| NMRC and IPM | qPCR assays | RKND, RfelG, Rasemb | Small mammal fles | |
| NMRC and IPM | Sequencing | ompB | ||
| Thailand | NMRC | ELISA | SFGR-ELISA-IgG | Cats |
| qPCR assays | Rick17b, Rtyph, RfelG, RfelB, Rasemb | Cat fleas | ||
| Sequencing | ompB | |||
| Ukraine | NMRC | ELISA | TGR-ELISA-IgG | Human |
| SFGR-ELISA-IgG | ||||
| Vietnam | NMRC | ELISAs | TGR-, SFGR-, and STGO-ELISAs-IgG | Human sera |
| ELISAs | TGR-, SFGR-, and STGO-ELISAs-IgG | Human sera | ||
| qPCR assays | Otsu47, Rick17b, Rtyph | Human buffy coats | ||
| qPCR | Otsu47 | Human PBMCs | ||
| Human eschars | ||||
| HMU and NHTD | Sequencing | tsa56 | Human PBMCs | |
| Human eschars | ||||
Source of assays: NMRC, Naval Medical Research Center; OSU, Ohio State University; InBios, InBios International, Inc; USAMRIID, United States Army Medical Research Institute of Infectious Diseases; IPM, Institut Pasteur de Madagascar; HMU, Hanoi Medical University; NHTD, National Hospital for Tropical Diseases.
Type of assays: ELISAs, enzyme-linked immunosorbent assays; qPCR, quantitative real-time PCR; MLST, multilocus sequence typing.
Specific assays: TGR, typhus group rickettsiae; SFGR, spotted fever group rickettsiae; STGO, scrub typhus group orientiae; IgG, immunoglobulin gamma; Rick17, a genus-specific qPCR assay for Rickettsia species (1st generation); Rick17b, a genus-specific qPCR assay for Rickettsia species (2nd generation); RKND, a genus-specific qPCR assay for Rickettsia species; Trick, a group-specific qPCR assay for tick-borne spotted fever group Rickettsia species; Rtyph, a species-specific qPCR assay for Rickettsia typhi; Rasemb, a species-specific qPCR assay for Rickettsia asembonensis; RfelG, a group-specific qPCR assay for flea-borne spotted fever group Rickettsia species; Orien16S, a genus-specific qPCR assay for Orientia species; Raesch, a species-specific qPCR assay for Rickettsia aeschlimannii; Rraoul, a species-specific qPCR assay for Rickettsia raoultii; Rslov, a species-specific qPCR assay for Rickettsia slovaca; Rmona, a species-specific qPCR assay for Rickettsia monacensis; Rconor, a subspecies-specific qPCR assay for Rickettsia conorii subsp. conorii; Rmass, a species-specific qPCR assay for Rickettsia massiliae; rrs, 16S rRNA gene; htrA, 47-kDa antigen gene; tsa56, 56-kDa type-specific antigen gene; 17 kDa, 17-kDa antigen gene; gltA, citrate synthase gene; ompA, outer membrane protein A gene; ompB, outer membrane protein B gene; sca4, surface cell antigen 4 gene.
Host samples: PBMC, peripheral blood mononuclear cell.